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Neuroethics DOI 10.1007/s12152-009-9053-9

Not so Fast. On Some Bold Neuroscientific Claims Concerning Human Agency Andrea Lavazza & Mario De Caro

Received: 21 June 2009 / Accepted: 12 October 2009 # Springer Science + Business Media B.V. 2009

Abstract According to a widespread view, a complete explanatory reduction of all aspects of the human mind to the electro-chemical functioning of the brain is at hand and will certainly produce vast and positive cultural, political and social consequences. However, notwithstanding the astonishing advances generated by the neurosciences in recent years for our understanding of the mechanisms and functions of the brain, the application of these findings to the specific but crucial issue of human agency can be considered a “pre-paradigmatic science” (in Thomas Kuhn’s sense). This implies that the situation is, at the same time, intellectually stimulating and methodologically confused. More specifically—because of the lack of a solid, unitary and coherent methodological framework as to how to connect neurophysiology and agency—it frequently happens that tentative approaches, bold but very preliminary claims and

even clearly flawed interpretations of experimental data are taken for granted. In this article some examples of such conceptual confusions and intellectual hubris will be presented, which derive from the most recent literature at the intersection between neurosciences, on the one hand, and philosophy, politics and social sciences, on the other hand. It will also be argued that, in some of these cases, hasty and over-ambitious conclusions may produce negative social and political consequences. The general upshot will be that very much has still to be clarified as to what and how neurosciences can tell us about human agency and that, in the meantime, intellectual and methodological caution is to be recommended. Keywords Human agency . Free will . Neuropolitics . Neuroethics . Social neuroscience

An Overly Optimistic Ideal A. Lavazza (*) Viale A. Doria, 17, Milano 20124, Italy e-mail: [email protected] M. De Caro Dipartimento di Filosofia, Università Roma Tre, Via Ostiense, 234, Roma 00144, Italy e-mail: [email protected]

The recent extraordinary developments of cognitive sciences and neurosciences have undeniably generated a radical change in the broader framework within which human nature is investigated. Nowadays many eminent neuroscientists and philosophers explicitly theorize that neurosciences are about to give us exhaustive and definitive answers to all the “big questions” (including enigmas as venerable as those

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concerning the sources of morality, the nature of knowledge, and free will) [1–9].1 It is also increasingly common to hear that we have reached a stage in which “the role of neuroscience in shaping and changing our society for the better” is so obvious that we should start basing our social and political choices on the acquisitions coming from that field [7:262]. These views give voice to an overly optimistic ideal, which has an important corollary. The ideal is that a complete explanatory reduction of all aspects of the human mind to the electro-chemical functioning of the brain is at hand. The corollary is that such reduction will certainly bring about positive consequences at the cultural, political and social level. This ideal and its corollary are generally in play when neurophysiological hypotheses that are still tentative or very controversial are taken for granted—at the expense of all other forms of understanding of the human mind and without a careful evaluation of how these simplifications may impact on the individuals and on society in general. It can be reasonably argued that the applications of neuroscience to the study of human agency are still in a phase of “pre-paradigmatic science” (in Thomas Kuhn’s sense)—which means that there are no shared conceptual and methodological assumptions yet that solidly structure the research practices of the researchers working in the area [10]. Indeed, the same boundaries of this new branch of scientific inquiry are not precisely defined yet. Given such situation, it is no surprise that, as we will see, in this area of investigation it is common to encounter methodologically defective projects, excessively broad or philosophically unfounded interpretations of recent discoveries, generalizations based on research that still lacks sufficient empirical proof, as well as biased understandings of observational and experimental

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It has to be said, however, that there is no shortage of neuroscientists and philosophers who have pointed to what they feel are the undue extensions, in philosophical, methodological and applicative terms, of the researches on the brain to issues of human agency [81–83].

results.2 All this leads to a theoretical framing of the mind/body that apparently is stable and unified, but in reality is very partial, conjectural, and perhaps not entirely coherent. There is also evidence of some concrete risks that may derive from the undue extension of certain neurobiological theories and methodologies (which are not been fully corroborated yet or remain insufficiently clear and coherent at the conceptual level) to psychological, social, and political phenomena. In the following we will discuss some cases in which the assumption that certain (indeed only tentative) neurophysiological hypotheses, which satisfyingly account for a specific component of human mind, may produce negative social and political consequences—such as increasing social discrimination or offering ‘scientific’ support to very questionable policies. As we will see, for example, shaky or flawed assumptions may suggest special treatments for conditions and behaviors that are thought to fall “outside the norm” as well as prescription of medical interventions for even slight behavioral dysfunctions. Moreover, in some extreme cases, these unwarranted assumptions may trigger potentially antidemocratic or immoral choices. In general, at the political and social level there is the risk that the unjustified ideal that a complete and exhaustive neuroscientific account of the human mind is at hand may facilitate the adoption of policies that allegedly have positive functional and biological consequences, without considering their possible negative implications for the quality of our lives. Two things should be noted at this point. First, most of the views that will be criticized in this article presuppose a thesis that we believe is ungrounded, i.e. that the normative categories through which we

2 In presenting a critical view similar to the one defended in this article, Racine, Bar-Ilan and Illes [84] have coined two neologisms, “neuro-realism” and “neuro-essentialism”. According to them, the first term can be used to describe “how coverage of fMRI investigations can make a phenomenon uncritically real, objective or effective in the eyes of the public. This occurs most notably when qualifications about results are not brought to the reader’s attention. For example, commenting on an fMRI study of fear, one article states, ‘Now scientists say the feeling is not only real, but they can show what happens in the brain to cause it’”. As to the term “neuro-essentialism”, it refers to the cases in which fMRI research is presented “as equating subjectivity and personal identity to the brain. In this sense, the brain is used implicitly as a shortcut for more global concepts such as the person, the individual or the self”.

Not so Fast. On Some Bold Neuroscientific Claims Concerning Human Agency

conceptualize human agency can be accounted in neuroscientific terms [11, 12]. Disapproving this thesis, however, does not imply the rejection of the naturalistic view of the mind. In itself, naturalism does not entail that every discovery of partial aspects of the functioning of the brain should be seen as a part of a coherent theoretical system that will finally produce the reduction of all mental and behavioral functions to neurophysiological ones.3 Second, it is not our intention to question the legitimacy of the neuroscientific investigations on human agency in general. Rather, our aim is to suggest that this is a much more complex field than it is normally taken to be and that a serious conceptual and methodological reflection on how to work in this area is at this stage indispensable [13]. In order to prove that this is the case, after briefly discussing some general methodological problems, we will analyze some conceptually confused and unjustifiably bold proposals. Finally, we will argue that one should carefully evaluate the unwelcome social or political consequences that a premature application of these proposals to our policies may generate.

Questionable Methods and Dubious Interpretations The astonishing empirical and applicative results achieved in just a few decades may explain and partially justify the current widespread fascination with neuroscience. In many respects, however, this is a very recent area of investigation and, unsurprisingly, it is frequently inflamed by vehement discussions. Because of their relevance for the neuroscientific investigations of human agency, some controversies concerning general methodological issues deserve attention here. A recent essay analyzes, in particular, the nature and potentialities of the most common used technology, i.e. the functional Magnetic Resonance Imaging (fMRI)—a technique for measuring haemodynamic

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For a defense of a liberal form of naturalism, which does not imply that, even potentially, the sciences of nature, including neurobiology, could exhaustively account for human mind and agency, see [85]. For one thing, for example, some of the explanations of the social sciences may well be proved to be informative and irreducible to the explanations of the natural sciences.

changes after enhanced neural activity—thanks to which an average 8 peer-reviewed articles a day were published in 2007 [14]. The same essay reports that “about 43% of papers explore functional localization and/or cognitive anatomy associated with some cognitive task or stimulus – constructing statistical parametric maps from changes in haemodynamic responses from every point in the brain”. However, the conclusions drawn from these studies, which aim at identifying the precise cerebral correlates of mental functions, often seem to ignore the intrinsic limitations of a methodology that, by generating the “colour pictures of the brain”, gives the “illusion of explanatory depth” (to use’s Frank Keil’s term) [15]. According to a recent discussion of the pros and cons of using brain-imaging by Nikos Logothetis, “the limitations of fMRI are not related to physics or poor engineering (…); they are instead due to circuitry and functional organisation of the brain, as well as to inappropriate experimental protocols that ignore this organization” [14]. There are good reasons, then, for believing that such methods are not sufficient for a whole understanding of the brain’s functions and disorders. Moreover, in this kind of research there is the risk of committing a “category error”, that is, assuming “the intuitively appealing notion that the organization of cognitive phenomena maps 1:1 fashion into the organization of the underlying substrates”. [16] The meaning of brain imaging is heavily dependent on the interpretations made by those who perform them. One reason for this is that the variations of regional cerebral blood flow upon which neuroimaging is based have a lag time of about 5 s, while human thought, although not instantaneous, has a lag time of a few tens of thousandths of a second. Therefore, the correlation between the two phenomena is not, and cannot, be perfect; and, although brain imaging studies do not take this into account, this fact has yet to be fully explained. Recently, it has also been reported that an increased blood flow (and, consequently, the socalled BOLD signal) has been detected in the visual cortex of experimental subjects just before they were to be shown one in a series of visual stimuli. In that case, the BOLD signal seems to be less informative than it usually thought to be. In an experiment performed by Sirotin and Das with rhesus macaque monkeys, two distinct components to the haemody-

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namic signal have been found in the alert animals’ primary visual cortex (V1) [17]. The first component is “reliably predictable from neuronal responses generated by visual input”. The second component, which has almost comparable strength, however, “is a hitherto unknown signal that entrains to task structure independently of visual input or of standard neural predictors of haemodynamics”. This result may challenge the common understanding of the link between brain haemodynamics and local neuronal activity—a link on which fMRI-BOLD is crucially based as a surrogate measure of neuronal activity and metabolism”. And that finding also suggests “the existence of a novel preparatory mechanism in the brain that brings additional arterial blood to cortex in anticipation of expected tasks” [17; cf. also 18 and 19].4 This phenomenon, however, is not explained by the traditional theory underlying fMRI. Finally, it has been argued that the interpretation of neuroimages not only depends on scientific considerations but also on cultural and anthropological ones. This happens, for example, when neuroimages are thought to be correlated to moral emotions: “Consider concepts such as ‘moral emotions’ that are based on assumptions that some emotions are moral and others not. They illustrate the cultural aspect of the interpre-

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A recent paper by Ed Vul et al. has sparked a great deal of debate among social neuroscientists even before publication [86]. It consists in a meta-analysis of fifty published articles that explore the high correlations between measures of personality or emotionality in individuals and fMRI scans of specific brain areas. The authors maintain that those “correlations often exceed what is statistically possible assuming the (evidently rather limited) reliability of both fMRI and personality/emotion measures”. A problem arises when “using a strategy that computes separate correlations for individual voxels, and reports means of just the subset of voxels exceeding chosen thresholds”. The authors call it “non-independent analysis”, and allegedly it “grossly inflates correlations”. Then they argue that “other analysis problems likely created entirely spurious correlations in some cases”. According to them, “if researchers select only highly correlated voxels, they select voxels that “got lucky”, as well as having some underlying correlation. So if you take the correlations you used to pick out the voxels as a measure of the true correlation for these voxels, you will get a very misleading overestimate”. Several neuroscientists have replied, however, that the study is flawed and unfair [87, 88; and a series of commentaries published along with 86]. The debate is surely bound to continue.

tation challenge, which is based on the fact that the self is defined in diverse ways” [20].5 These are methodological worries concerning neuroscience in general. However, when one considers what is going on with the neuroscientific investigations of human agency in particular, the situation looks even more complicated. In the following paragraphs we will discuss this issue by considering three vibrant areas of investigation: free will, neuropolitics and social neuroscience. Neurosciences and Free Will The venerable problem of freedom lies at the heart of the intuitive views of human agency, but it also has crucial implications for our moral, political and social views. Since Benjamin Libet’s seminal research, one of the boldest neuroscientific projects has been to solve this problem [21, 22]. Very frequently, however, this kind of research has been spoilt by false steps—if not by real blunders—at the conceptual and methodological level. In order to clarify this point, it is useful to analyze a recent but already influential article, which is meaningfully entitled “Unconscious Determinants of Free Decisions in the Human Brain” [23]. In the experiment described in this article, the subjects were asked to relax and then “when they felt the urge to do so, they were to freely decide between one of two buttons, operated by the left and right index fingers, and press it immediately” [23]. In order to determine the moment in which the decision was made, the subjects had to fixate on the center of the screen of a computer where a stream of letters was running with no interruption; in particular, they had to notice which letter was on the screen when they made their decisions. In meantime, their brain activity was measured by using fMRI. In some respects, the research described in this article is certainly an improvement over Benjamin Libet’s famous pioneering experiments on the neuro5 Another recent line of criticism of the indiscriminate use of neuroimages questions the statistical methods underlying the interpretation of fMRI data. Indeed, according to Colin Klein, “neuroimages present the results of null hypothesis significance tests performed on fMRI data. Significance tests alone cannot provide evidence about the functional structure of causally dense systems, including the brain. Instead, neuroimages should be seen as indicating regions where further data analysis is warranted” [89].

Not so Fast. On Some Bold Neuroscientific Claims Concerning Human Agency

logical determinants of actions. More specifically, Soon et al. appeal to a more sophisticated instrumentation (fMRI instead of Libet’s EEG) and ask the subjects to perform a more complex task (to make a decision instead of executing an action decided from the onset). In addition, this experiment claims to have reached significantly more impressive results than Libet had, as it is clear from the abstract of the article. There has been a long controversy as to whether subjectively “free” decisions are determined by brain activity ahead of time. We found that the outcome of a decision can be encoded in brain activity of prefrontal and parietal cortex up to 10 s before it enters awareness. This delay presumably reflects the operation of a network of high-level control areas that begin to prepare an upcoming decision long before it enters awareness [23]. In this abstract, it is worth noticing that the word “free” is put in scare quotes (something that, by the way, does not happen in the title of the article). This is a clear signal of where the authors stand in the discussion on free will, i.e., they seem to sympathize with “incompatibilism” (the view that causal determination and freedom are incompatible), and more specifically with the “illusionist” version of that view, which claims that—since in fact our deliberations and actions are causally determined, and possibly, as it is claimed in this experiment, even predictable from a neurobiological point of view—free will is plainly impossible. In this light, Soon et al. argue that the subjective feeling of freedom does not have any objective correlate. The implicit moral, then, is that free will is nothing more than an illusion.6 In the first place, however, this article is vulnerable to some standard objections, which were already raised against Libet. For example, the experiment described in the article presupposes at least two very controversial claims, i.e., that neurological processes and conscious processes can be measured in comparable ways and that the subjects’ mental events relevant for this experiment—deciding which button to press, noticing that one has made that decision, fixing the screen of a computer, and being aware of the letter that is on the screen when one makes the decision—are all simultaneous. Moreover, as noticed by Daniel Dennett,

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Cf. [90, 91].

this kind of experiments seem to assume an obsolete Cartesian vision of the mind, according to which our conscious activities are performed in front of a mysterious “I”, who witnesses, and is able to report, them [24:ch.8]. Moreover, as said above, serious doubts have recently been cast with regard to how the methodology of pattern recognition is used in these kinds of experiments in order to individuate causal correlations between neural processes and specific mental activities and actions. These are standard objections; more specific ones, however, can be raised against the claim made by Soon et al. First of all, even granting that their experiment is methodologically sound, one could still wonder which theory of free will it could corroborate. Certainly, it could be legitimate to use it in support of the illusionist view of free will, as Soon et al. appear to do. The experiment, however, could also be used to support “compatibilism”, which is perhaps the most common view about free will, at least in contemporary Anglophone philosophy. According to this view (defended, among others, by Locke, Hume, Mill and Dennett), to act freely only means to perform the actions that one intended, desired or willed to perform— and this is perfectly compatible with the possibility that one’s intentions, desires or wills are totally determined.7 More surprisingly, perhaps, Soon et al.’s interpretation of their experiment is also compatible with the other major conception of freedom, i.e. libertarianism—the view that appeals to the necessary presence of indeterministic gaps in the causal processes that generate actions.8 The supporters of this view, in fact, could appeal to the fact that, in this experiment, the accuracy of the predictions by the experimenters about which button the subjects will press is in the order of 60%. This is a statistically meaningful figure, of course, but it leaves a lot of room for those who want to argue that the 40% of inaccuracy is not only due to our present-day epistemic limitations but is a consequence of the objectively indeterministic causal structure of the world (this is a controversial view, of course, which appeals to the alleged macroscopic consequences of

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According to many authors, including Leibniz, Hume, J.S. Mill, and legions of contemporary philosophers, intentions, desires and wills have to be causally determined if freedom is to be possible at all. The opposite would actually generate mere casualness, which is incompatible with freedom. 8 Cf. [92, 93].

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quantum indeterminacies; but one that is perfectly consistent with the results of Soon et al.’s experiment). It should be clear that this experiment adds something very interesting and may even represent a major breakthrough for the intense debate dealing with the inaccuracy of conscious reports on our own mental lives. A different issue, however, is whether it has anything interesting to say about the free will problem, as is boldly claimed by the title, the abstract and the article itself. When it comes to this question, it is important to notice that we consider many of our actions as free even if we have performed them unawarely. To give an example, let’s imagine a speaker that, after a lecture, is going to drink a glass of water, but before doing so is asked a difficult question. She then starts thinking about how to answer that question, and fails to notice that she is actually accomplishing the action of drinking. However, if afterwards she is asked whether she freely drank the glass of water, she replies that she did— even if she did not pay any attention at the moment in which she did so. Briefly, it can happen that we are not aware of performing actions that we would subjectively consider free. Freedom does not imply consciousness, then; and so, by the logical principle of contraposition, lack of consciousness does not imply lack of freedom. Thus experiments like Libet’s or Soon et al.’s, which are certainly relevant for understanding the limitations of our awareness in acting, are not necessarily relevant for the debate on freedom. But there is more. The gist of Soon et al.’s article is the support that it allegedly offers to the idea that our subjectively free decisions are not objectively free. It is very doubtful, however, that this article, with its related experiment, deals with free decisions at all (not even in the merely subjective sense, then). It can be argued, in fact, that the allegedly “free decisions” discussed in the article were neither free nor genuine decisions. First, if one reflects upon the description of the experiment, it is evident that they were not “free” even in the subjective sense.9 The article explains that the subjects received instructions such that “when they felt the urge to do so, they were to freely decide between one of two buttons”.10 Now, feeling the urge to do something is not a necessary nor a sufficient

condition of a free decision. It is not a necessary condition, since in the vast majority of cases in which we think we act freely, we do not feel any urge to act (the reader has not felt the urge to read the phrase he or she has just read). Second, it is not a sufficient condition either, since very often when we feel the urge to do something, no free decision is involved, and we on the contrary feel constrained (this happens, for example, when we feel the urge to sneeze or yawn in public). The set of actions that are preceded by subjectively free decisions has (at most) a little overlapping with the set of actions that are preceded by urges to perform them. Undoubtedly, then, the latter should not be taken as prototypical examples of the former, as it happens in this article. Therefore, Soon et al.’s “free decisions” are not free at all, not even in the merely subjective sense. What is worse, however, is that these “decisions” are not even genuine decisions, since—as assumed by both decision theory and common sense—one can talk of a rational decision (which is the kind of decision that is at stake in the discussion on freedom) only when, in a situation of uncertainty, an agent chooses between alternatives possibilities, according to her preferences. Given the way Soon et al.’s experiment is set, however, the subjects do not have any preference between pressing the right or the left button. Very probably, in cases like that, in which nothing relevant is at stake, it is plausible that the subjects press either button automatically, paying no attention to which “decision” could be the best for them—exactly because no genuine preference is at stake. So Soon et al.’s “free decisions”, besides not being free, are not even genuine decisions. It seems safe to say, therefore, that the gist of this article—and more generally of all attempts at disproving the intuitive belief in freedom along these lines—is still substantially ungrounded.11 Neuropolitics Cognitive neuroscience (the new area of investigation that concerns the genetic/neural mechanisms underlying the cognitive functions) finds new and important applications every day [25]. One of the newest 11

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Bennett and Hacker [81: 228–231] raised a similar criticism against Libet’s experiment. 10 Our italics.

Enlightening analyses of what neurosciences can do for the free will issue are developed in [94]; (Roskies, A. 2009. Can neuroscience resolve issues about free will?, unpublished manuscript).

Not so Fast. On Some Bold Neuroscientific Claims Concerning Human Agency

applications is neuropolitics, which aims at studying the neurobiological determinants of the political and ideological choices of individuals and groups. Understandably, being at a very early stage, this branch of science is still in the process of defining its object, research tools and methodological rules. Nevertheless, this is an area in which the tendency to spread preliminary and sometimes controversial results in the public media as if they were solid scientific achievements is particularly evident. In November 2007, a group of seven neuroscientists led by Marco Iacoboni of UCLA published an oped piece in the New York Times in which they described a test performed on some undecided voters, who were asked to grade, on a scale from one to ten, their degree of identification with the main candidates of the two most relevant political parties [26]. An fMRI scan was performed on the subjects, while they were presented photographs and videos of those candidates. The authors highlighted the fact that the mere mention of the words “Democrat” and “Republican” led to a high degree of activity in the amygdala of the experimental subjects. According to Iacoboni and his colleagues, that phenomenon indicated anxiety, since politicians are generally considered harbingers of threats and promises, so their presence might prompt mixed feelings. The New York Times was immediately flooded with protests from the scientific community. “As cognitive neuroscientists who use the same brain imaging technology,” wrote seventeen experts in cognitive science “we know that it is not possible to definitively determine whether a person is anxious or feeling connected simply by looking at activity in a particular brain region. This is so because brain regions are typically engaged by many mental states, and thus a one-to-one mapping between a brain region and a mental state is not possible” [27].12 In spite of these complaints, during the following months there was a dramatic increase in brain imaging studies performed by private neuromarketing firms, which promised to identify the immediate, unconscious reactions of potential voters to different candidates [28].

12 The group of scientists complained also that the data presented by Iacoboni and colleagues was not peer-reviewed. It has to be noted, however, that Iacoboni’s team had already published the results of similar research in a peer-reviewed journal [95].

Even though the scientific validity of such studies was questionable, they certainly took advantage of the above-mentioned “illusion of explanatory depth”. Politics, especially during the electoral period, is one of the issues on which traditionally the media focus the most. One can therefore understand why neurophysiological investigations like the one just mentioned—presented as allegedly solid scientific analyses of the mechanisms through which electors decide how to vote—may get so much attention. Still, the very limited data on which they are based, and the very controversial methods that are used to collect and evaluate those data, hardly justify the aura of credibility that surrounds these kinds of investigation [29]. Drew Westen et al. reported that, during the 2004 U.S. Presidential election, committed partisans who underwent fMRI scans responded with the activation of different cerebral areas when presented with blatant inconsistencies attributed to Democratic and Republican candidates. In these cases, the “instinctive” judgment driven by unconscious emotions seemed always to prevail, since the subjects showed emotion-biased motivated reasoning, “a form of implicit emotion regulation in which the brain converges on judgments that minimize negative and maximize positive affect states associated with threat to or attainment of motives” [30]. However, Westen et al. noted that in this situation “motivated reasoning was not associated with neural activity in regions previously linked to cold reasoning tasks and conscious (explicit) emotion regulation” [30]. This suggests that the emotions that condition the “intuitive judgment” may strongly influence the subsequent motivated judgment as well. This result is very interesting, but the influence of cultural factors on this kind of political behavior has still to be assessed. For example, it happened frequently, over the course of American history, that while one election was won by a Presidential candidate with a populist agenda, the next one—in which the electorally body was of course very similar—was won by a candidate with a much more realistic agenda. This seems to suggest what is indeed obvious to common sense, i.e., voters are not stable in their political preferences and may change their minds from one election to the next. However, it seems very plausible that, in these changes in political orientations, factors of a cultural or sociological nature (that is, the agential dimension) play a very relevant role. To put it differently, it is difficult to deny that, at least in part,

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the relevant cultural and sociological factors are the causes, instead of being the effects, of the neurobiological differences that one can detect in the brain images of voters of different political tendencies. If this is so, in order to explain voters’ behavior, neuroscientific data are not enough; one also needs to bring into play some essential cultural information. A study by David Amodio et al., which concludes that the liberal or conservative orientations of voters have precise neurocognitive correlates, can be evaluated in this light [31]. The authors argue that individual political attitudes can be associated with differences in their general neurocognitive functioning. In particular, liberals appear to be more sensible to complex information and situations that can lead to alternative or conflicting evaluations; in other words, they seem to be more willing to reconsider their own choices and take different opinions into account. On the other hand, conservatives seem to be more prone to hold on to their positions and to have less nuanced attitudes. The authors of this article claim that such different attitudes depend on the respective activity of the anterior cingulate cortex, which is responsible for choosing between alternative courses of actions and resolving cognitive conflicts. A greater activity in that part of the cortex seem to imply a greater receptivity towards the elements that can modify our automatic or habitual responses, while a reduced activity in that area may lead to a decreased sensitivity to new information and to a stronger loyalty toward one’s original ideas. Moreover, in computer tests, Republican voters seem to do better at tests in which the answers are constant, while Democratic voters do better in tests that go back and forth between negative and positive answers. The main objection to these studies is that it is necessary to distinguish between two approaches to brain imaging. In the first and most common approach, “the experimenter tries to manipulate the mental state of a subject in order to then observe the evoked brain activity” [32]. This approach is termed “forward inference”. However, “the application of neuroimaging to political questions does not involve ‘forward inference’ [but] relies upon the opposite approach. Instead of determining the brain region associated with a particular behavioural state, a ‘reverse inference’ study attempts to identify the behavioural state of subjects by observing their brain activity (…). The problem is that these reverse inferences are only as good as the evidence that

supports a unique mapping of a particular mental operation to a particular cortical region” [32]. The fact that the amygdala responds to the photos of a presidential candidate does not necessary indicate anxiety; indeed, it could also indicate positive emotions. Furthermore, the activation of the amygdala may also be activated by certain physical characteristics of the candidates (the subjects are only seeing their photos, not reading or listening to their speeches), rather than by their political views. Finally, even if we grant that there may really be an increase in anxiety associated with a candidate’s photo, this reaction may still have other causes: for example, it may depend on the fact that a candidate is not doing as well as his or her supporters hoped. Once again, the causal relevance of conceptual factors should be evaluated very carefully before concluding that the activity of the anterior cingulate cortex can account for people’s political tendencies (and, even more, before claiming that it gives reliable indications of how they will vote at the next elections). Another interesting case is offered by the genetic studies of James Fowler et al., which have had great resonance in the popular media [33]. In the first one, the authors looked at two genes which, in their opinion, may account for “a significant proportion of the variation in voting turnout” (53% to 72% traced to genetic influences) [34]. Matching public voter turnout records in Los Angeles to a twin registry, the researchers studied the heritability of political behavior in monozygotic and dizygotic twins. Using data from the National Longitudinal Study of Adolescent Health, they then found out that “individuals with a polymorphism of the MAOA gene are significantly more likely to have voted in the 2004 Presidential elections” [35]. Additionally, the gene-environment interaction between a polymorphism of the 5HTT gene (linked to serotonin), coupled with the tendency to participate in religious functions, increases the likelihood of voter registration. In brief, people with a certain polymorphism of the MAOA gene and of the 5HTT are better at handling stress and in particular the specific kind of stress associated with politics and voting. But, obviously, one can observe that stress is not the only negative feature involved in politics: for example, voting can be perceived as annoying, boring or time-consuming. Another recent study compared “the similarity of partisan strength in identical twins who share all their

Not so Fast. On Some Bold Neuroscientific Claims Concerning Human Agency

genes to the similarity of partisan strength in nonidentical twins who share only half of their genes” [36]. It was found that heritability accounted for almost half of the variance in the strength of partisan attachment (even if it did not account for the specific political orientation one had). Finally, C.T. Dawes and J.H. Fowler found that “an extensive studied gene that regulates the dopamine system is associated with the tendency to identify with a political party” [37]. In particular, people with two A2 alleles of the DRD2 dopamine receptor gene are 8% more likely to identify as partisan than those with no A2 alleles. The DRD2 gene is believed to play an important role in the developments of social attachments, since better dopamine signalling is commonly associated to more social attitudes. The authors, however, honestly emphasize that they “have only found an association and cannot make any causal claims about relationships between the DRD2 gene and either partisanship or turnout” [37]. In another important study, C.C. Ballew II and Alexander Todorov asked the participants to evaluate the political competence of the two main candidates in some American political races for governor and senator, by only looking for a few hundreds milliseconds at photographs showing the candidates’ faces [38].13 Rather surprisingly, the evaluation of competence obtained by only looking very briefly at the pictures of the two candidates of each race anticipated rather accurately the final result of the elections—and, surprisingly, more accurately than predictions done by considering the evaluations of competence offered by the subjects of this experiment after a longer reflection period. In particular, students tested in 2006, before the actual elections, correctly picked the winners of 68.6% of the gubernatorial races and 72.4% of the Senate races. These results suggest that the unconscious snap judgments, based on looking at the candidates’ faces, strongly influence how one will vote at the elections. This is a relevant study since it shows the crucial causal role played by unconscious factors in the causation of decisions that are generally considered fully conscious and rational by the agents that make them (“effects on appearance on voting decisions may be subtle and not easily recognized by voters” [38]). 13

The participants in the experiment did not have any previous knowledge of the candidates whose political competence they were asked to assess.

This interesting result, however, should not be taken as the proof that we are on the verge of offering neurophysiological explanations of electoral behavior, as it is sometimes claimed. In the same article, Ballew and Todorow discuss a similar experiment, which suggests that the cultural context can strongly influence the snap judgements of competence of political candidates that are based on a quick look of their facial traits—and consequently (considering that snap judgments seem to reliably anticipate the result of the actual elections) also the way in which the electors will vote. More precisely, using a morphing technique, Little et al. submitted the morphed faces of George Bush and John Kerry to the subjects. In a “time of war” context, the subjects tended to prefer the former (who was perceived as more masculine), while in a “time of peace” context, they tended to prefer the latter (who was perceived as more intelligent and forgiving) [39]. There is no doubt, however, that the perception of a determined period as a time of peace or a time of war depends on a number of cultural, political and psychological factors. This experiment, therefore, suggests that also cultural, political and psychological factors may play a crucial causal role in determining one’s snap judgments regarding political competency and, consequently, in determining how one will actually vote. Once again, the causal path that brings about our acting is much more complex than it is currently assumed in the discussions concerning the explanatory potential of neuropolitics. Social Neuroscience Social neuroscience investigates the neurobiological bases of social processes and behavior. This is another area in which conceptual and methodological confusions are not infrequent and often are combined with overoptimistic goals. Recently, stemming from research on the neurobiology of mate attachment in voles, Patricia Churchland has argued that the density of the receptors for the neuropeptides arginine vasopressin and oxytocin in the ventral pallidum and the nucleus accumbens marks the crucial difference in mating behavior in mammals and, probably, also in humans [2]. Other studies showed pair-bonding differences between adult men with the “polygamous” variant of the gene for the arginine vasopressin receptor and those without [40]. A brief review

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article, published in one of the most widely-read science journals, argued that “researchers are attempting to isolate and identify the neural and genetic components underlying this seemingly uniquely human emotion. Indeed, biologists may soon be able to reduce certain mental states associated with love to a biochemical chain of events” [41]. Churchland recognized that “philosophically, these results were alarming. Monogamy seemed to be a complex choice, requiring rational adherence to a universal rule and conscious self-control” [2]. But, according to L. J. Young, the philosophical doubts are to be overridden, as “drugs that manipulate brain systems at whim to enhance or diminish our love for another may not be far away (…) and perhaps genetic tests for the suitability of potential partners will one day become available”, substituting “our gut instincts in selecting the perfect partner” [41]. The really important point here is not whether and why monogamy is evolutionarily justified or what the social consequences could be if we found out that the level of faithfulness toward the partner can be accounted by referring to brain configurations. What really matters is that voles, although having some basic form of selfawareness, certainly are not able to evaluate their own behavior and take into account its impact on other individual voles and on their community. The voles with fewer vasopressin and oxytocin receptors change partners more often and care less for their offspring, while voles with more of these receptors are better parents and are monogamous. That’s all. There are no other descriptive or evaluative plans. The species Homo sapiens sapiens, instead, can gain significant advantages from knowing the biological mechanisms that contribute to behavior; but, at least presently, there are no convincing reasons for doubting that other considerations and motivations, especially normative ones (which refer to what one should do or not do) can influence the course of action chosen by individual humans. In general, it may be true that “practical reasoning mainly consists in finding a good solution to a constraint satisfaction problem. Deduction—the sentimental favourite of logicians—plays at most a minor or post hoc role” [2]. Nevertheless, the fact that one can explain with increasing precision why things go a certain way does not mean they have to go this way. A person may feel hurt if abandoned by a partner, children can suffer if their parents do not pay enough attention to them, and a society can feel satisfied if its

members adhere to a certain type of conduct. There is no doubt that these events have neurobiological causes and, very probably, also a relevant evolutionary history. The interesting question, however, is whether an exhaustive causal explanation of these phenomena can be offered in neurobiological and evolutionary terms. For example, the fact that nowadays we can understand better, and even manipulate, the biochemical conditions of love does not mean that we can offer a comprehensive biological explanation of what love and sex behavior are and what they mean for our lives. Moreover, some biological forces—which in this perspective are interpreted as overriding the cultural ones—may well be not adaptive. They may even prove to be socially dysfunctional: such as when they allow personal choices that are socially burdensome or damaging. Other correlations that could be interpreted improperly include that connecting the size of the amygdala with aggressiveness in teenagers. The relationship between aspects of the adolescents' brain structure and their affective behaviour, observed in the context of parent-child interactions, was studied by Whittle et al., who “found a significant positive association between the volume of the amygdala and the duration of adolescent aggressive behaviour during these interactions” [42]. They “also found male-specific associations between the volume of prefrontal structures and affective behaviour, with decreased leftward anterior paralimbic cortex volume asymmetry associated with increased duration of aggressive behaviour, and decreased leftward orbitofrontal cortex volume asymmetry associated with increased reciprocity of dysphoric behaviour” [42]. According to the authors, these findings suggest that the adolescent brain structure is associated with the affective behavior and with its regulation in the context of family interactions, and that there may be gender differences in the neural mechanisms underlying affective and behavioral regulation during early adolescence. However, while some correlations may help us to understand anti-social behavior better, other correlations can be misleading if they are not adequately evaluated—or, even more, if they are taken as the last word on the issue. In particular, also in this case it seems very probable that some cultural and sociological factors play a crucial role in bringing about aggressive behavior (for example, in the cultures in which martial virtues are highly evaluated, aggres-

Not so Fast. On Some Bold Neuroscientific Claims Concerning Human Agency

siveness may easily be more common than in culture praising tolerance and non-violence more). A recent study of paedophiles was hailed as an important step forward in understanding the tendency to commit this type of sexual crime not as a consequence of childhood trauma or abuse, but rather as a cerebral development problem [43]. Indeed, what was proven was only that the 65 subjects analysed through T1-weighted magnetic resonance imaging (MRIs) showed significant negative associations between paedophilia and the white volumes of the temporal and parietal lobes bilaterally. Regions of lower white matter volumes followed, and were limited to, two major fibre bundles: the superior fronto-occipital fasciculus and the right arcuate fasciculus. Because those brain areas “connect the cortical regions that respond to sexual cues, these results suggest (1) that those cortical regions operate as a network for recognizing sexually relevant stimuli and (2) that paedophilia results from a partial disconnection within that network” [43]. However, it also appears that the chosen control group—sixty-two non-sexual offenders—was not well picked, since the specific characteristics of the paedophile brain (assuming that such a thing exists) would be better identified if in the comparison also other types of sexual offenders (such as rapists) were included.14 As this experiment has been set, instead, any significant difference in the brain of the paedophiles could be related to their generally aggressive sexual tendency, and not to their specific phedofiliac inclinations. Furthermore, as suggested by a wide body of literature [44–46], fibre bundles are also involved in the lateralisation of language as well as in hallucination and in other illusory phenomena. Therefore different interpretations of the experimental findings mentioned in this study are possible and a careful scientific scrutiny is needed in order to establish which is the correct one. Some recent interpretations of paedophilia as a mainly cerebral problem seem also to suffer from a confusion between neurogenetic and psychogenetic causes. Indeed, a change in the volume of the white matter could be due to either endogenous biological factors (such as aging) or to broader environmental

14

This comment was inspired by an anonymous post on the Brainethics website (accessed on 21 January 2008).

factors (such as the development of certain areas of the primary motor cortex in people who perform certain activities). The mere observation of diversity tells us nothing about its cause. Another questionable assumption that may be drawn from a single study concerns the idea that the differences observed between the brains of heterosexual and homosexual men and women are the cause of the homosexual tendencies [47]. Allegedly this happens, for example, when a cerebral asymmetry and some functional connections in homosexual subjects, which cannot be “primarily ascribed to learned effects”, are postulated to depend on “a linkage to neurobiological entities” [47]. As it is well known, a vast and complex debate over the origins of homosexuality opposes the advocates of social constructivism to those of essentialism, and supposing that a single experiment can assess the whole discussion seems unrealistic [48].15 At any rate, as a matter of fact, the plasticity of the brain is well known, as is the possibility that its structure and functions can change according to life experiences. Therefore, the differences observed in the links between amygdala, limbic system, and prefrontal cortex between gay men, heterosexual women, heterosexual men, and lesbian women may still be the effect, not the cause, of personal experiences. Finally, one can mention an aspect that has come under investigation only recently, but that may become very important. That is the fact that one’s cultural background can influence the neural activity that underlies cognitive functions [49]. People who grew up in different cultures have specific activation modalities for cerebral areas linked to certain functions. As the level of the functions under investigation increases—from the capacity to gauge the length of a line to ascribing characteristics to a given human being—one can notice cases in which slightly different areas are activated, even for the same task. Summarizing, at present there is no evidence that cultural and social variables can be eliminated from our explanations of human actions, and even from the interpretation of neuroimaging studies.

The social constructionist approach to homosexuality is “that there is no ‘natural’ sexuality; all sexual understandings are constructed within and mediated by cultural understandings”; on the contrary, essentialism is the view that “sexuality is innate or biologically driven”, “a deep, unchosen characteristic of persons, regardless of whether they act upon that orientation” [48].

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Unwelcome Political and Social Effects In the last section we have mentioned some dubious approaches to the neuroscientific investigation of human agency. Those approaches present relevant problems as to the methodology and the goals they set for the experiments and/or to the interpretations of experimental data. But there is more. In those areas of study there is also the concrete possibility that, by taking for granted very ambitious but preliminary approaches and misinterpreting the experimental data, negative political and social consequences may follow. However, before considering some examples of those potentially negative consequences, something more has to be said about the cultural framework in which these discussions take place. The crucial factor is, unsurprisingly, the vast appeal that the neurosciences exercise in our culture. Nowadays the common perception is that neurosciences are “more scientific”, “truer”, than all other forms of investigations—and thus should have the final word— because they can see into, and explain entirely, the “human engine”, i.e. the brain (considered as the source of all human behavior, feelings, thoughts, attitudes, goals and desires). Once again, this appeal is understandable, given the astonishing epistemic progress that those sciences have produced in recent years. Still, as we have argued, the widespread expectation that the neurosciences are on the verge of completely explaining human agency—and, for this reason, have an absolute primacy on the other forms of investigation—is, at the present state, unjustified.16 It has been argued, as a general epistemological claim, that rhetoric plays a crucial role in the dynamics of science.17 In this spirit it has been observed that “communities that produce science and communities that respond to science are profoundly shaped by the ways in which that science is communicated” [50]. If so, however, it should be no surprise that the way in 16

One could make the case that the often unjustified expectations that today surround neurosciences are similar to those that were provoked by the astonishing results that Newtonian physics reached in its own domain. For a couple of centuries, most intellectuals were confident that Newtonian explanations of fields as different as atomic theory, ethics, and the social sciences were at hand. We now know that that confidence was ungrounded—but this fact, of course, does not affect the huge intellectual value of the Newtonian theory in itself. 17 Cf. [96] for a defense of this claim based on the discussion of some historical cases.

which neurobiological experiments are presented may sometimes distort, at least in part, the perception of their meaning and value, especially (but not only) among the general public. This idea is confirmed by some recent studies that show that rhetorically based delusions are persistent and tend to hold even when sheer neurobiological experimental data are presented. Indeed, our culture seems increasingly attracted and captivated by the already mentioned “illusion of explanatory depth” of the neurosciences [15]. Non-specialists, for example, tend to have the impression that, in itself the employment of PET or fMRI imaging provides a better understanding of cognitive processes than the employment of more traditional physiological and psychological methods. A study conducted by Deena Skolnick Weisberg et al. showed that it is sufficient to add some irrelevant information about underlying alleged brain mechanisms to make people judge more positively an alleged explanation of a psychological phenomenon [51]. For example, when three groups of subjects— respectively composed of lay people, students (taken from an introductory class in cognitive neuroscience) and professional neuroscientists—read four versions of a simple text explaining the effect of perceptual illusion, their respective evaluations primarily depended on the objective correctness of the contents; however, the presence of references, not necessarily useful, to neuroscience (such as the mention of neurobiological experiments or the explanation of the alleged role of specific brain areas involved in perceptual illusions) strongly influenced their judgments. More precisely, it was not the case that, when neuroscientific evidence was added, the subjects interpreted an inadequate explanation as fully satisfactory; but they found that explanation more acceptable (the scientists, however, avoided the trap and were not deceived). Another study, conducted by David McCabe and Alan Castel, highlighted the fact that cognitive neuroscience papers that present brain imaging pictures (especially if derived from fMRI) are seen as more “scientific” by experimental subjects who are asked to compare those articles with others that contain other kinds of illustrations, such as graphs and drawings [52]. According to the authors, the lure and credibility of brain imaging derives from its intrinsic power of persuasion. To put it differently, it seems that uninformed people are easily misled by the appeal of the reductionist view according to which the

Not so Fast. On Some Bold Neuroscientific Claims Concerning Human Agency

ultimate explanations of psychological phenomena have to be given in neurophysiological terms. This is unsurprising, if we consider how pervasive the view is that, in general, macroscopic phenomena are reducible to, and should be explained by, microscopic ones (an idea, by the way, which is in general philosophically controversial). This is probably why in the studies just mentioned the mere mention of an explanatory level that is considered more fundamental—that of the neurological phenomena— gives the impression of a greater insight. Judy Illes et al. have made the interesting remark that since the media coverage of neuroscientific findings is almost always positive or at least neutral in tone, one should be very prudent in employing these findings in, say, courtrooms, because laymen may be conditioned by their positive biases in evaluating how relevant and meaningful these findings are for the cases they have to pass judgment on [53]. In fact, the reductionist bias may easily contribute to an overemphasis on interpretations that, even if not supported by adequate experiential data, are perceived as more credible because of their association with the evocative images of a multicolored brain. Another interesting case of possible unwelcome consequences of inaccurate neurophysiological investigations is offered by the research on free will. Kathleen Vohs and Jonathan Schooler have argued, on an experimental basis, that our acting morally draws upon the idea that we have the ability to act freely [54]. More specifically, according to those authors, people who believe that causal determinism is both true and incompatible with freedom will tend to relax their moral standards much more than people who hold the intuitive view that we do have freedom (the former group, for example, will consider cheating more acceptable from a moral point of view than the latter). In this light, Vohs and Schooler claim, “if exposure to deterministic messages increases the likelihood of unethical actions, then identifying approaches for insulating the public against this danger becomes imperative”. If this is correct, claiming that we have good reasons for believing in the illusoriness of freedom, besides being intellectually unjustified, may also have unwelcome social consequences.18

18

On this line, cf. [97, 98]. A different point of view is defended in [99, 100] and also [94].

Another interesting discussion concerns what the consequence for the theory of punishment should be if freedom (and consequently moral responsibility) were proven illusory, as claimed by many neuroscientists today. According to Joshua Greene and Jonathan Cohen, potentially this view may have very progressive consequences, since it makes no sense to punish individuals who could not have behaved otherwise due to the genetic-cerebral determination of their behavior: “At this time, the law deals firmly but mercifully with individuals whose behaviour is obviously the product of forces beyond their control. Some day, the law may treat all convicted criminals this way. That is, humanely” [55]. Greene and Cohen’s view, however, is simplistic. Giving up the idea of free will implies that one has to abandon the galaxy of notions that essentially depends on the idea of freedom—such as responsibility, desert, merit, and guilt. But, without these notions, one is left with a purely utilitarian theory of punishment, according to which any punishment could be inflicted to anybody, as long as the general utility were increased. In order to avoid this inhumane result, even many of the most important utilitarian views accept, very reasonably indeed, the idea of “negative retribution”, according to which nobody can be punished who is not guilty. The classic reference of this view is H.L.A. Hart who, while conceiving the justification of punishment in purely utilitarian terms, regarded negative retribution as a “limiting principle”, aimed at constraining the distribution of punishment by avoiding patent injustices [56]. In this perspective, the criminal law “will not or ought not punish a victim-perpetrator—even if such punishment would provide a net benefit to society— because in some way the victim-perpetrator lacks the appropriate moral desert” [57:576].19 Evidently, in formulating the idea of negative retribution, instead of moral desert one could mention any of the other concepts linked to the idea of free will. What matters, at any rate, is that many of the most influential utilitarian theories of punishment— those based on Hart’s intuition—essentially refer to one or the other of the concepts of the free will 19 It should be noted, that while the Hartian version of utilitarianism accepts the idea of negative retribution, it refuses the idea of positive retribution—i.e., it does not claim that all people who deserve punishment should be punished, whatever consequences their punishment may have.

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galaxy, in order to constrain the distribution of punishment and avoid the unwelcome consequences of pure utilitarianism. But that means that—as of course do all retributivist views—those utilitarian views presuppose that agents do have free will (most frequently this is intended in the sense specified by the compatibilist tradition, according to which free will is compatible with causal determinism, and perhaps even requires it).20 Vice versa, if one adopts the illusionist view of freedom, by claiming that we do not have free will in any sense—as today many tend to think, as seen above, on the basis of neurological considerations— then all the concepts of the free will galaxy (desert, responsibility, guilt etc.) have to be abandoned; but thereby one loses the conceptual tools needed for appealing to the notion of negative retribution. It follows that giving up the idea of free will may produce a consequence that is opposite to that envisaged by Greene and Cohen, since in that scenario only purely utilitarian considerations would become relevant for deciding when punishment is legitimate. Certainly, not good news for those who care about the humanity of punishment. Good reasons can also be given for being very cautious before trying to apply the bold claims of neuropolitics in order to direct political conduct. It cannot be denied, of course, that neuropolitics has an interesting potential as a research field: studying the genetic influences and cerebral mechanisms that underlie our political choices and orientations may certainly produce significant results [58]. Nevertheless, extending these results beyond their specific contexts and presupposing carelessly that cultural factors play a peripheral role (if any) in defining the political views of a person can lead to oversimplifications and generate unwelcome consequences. Very probably also because of the general allure of the neurosciences, it is common nowadays to overestimate the solidity of neuropolitics, and favor the belief that our political actions have genetic and neurological determinants that tend, for example, to cause one’s unconscious emotive responses to candidates and parties and thereby to determine one’s electoral behavior. Such a belief, if taken for granted, may easily lead politicians to assume that citizens On the compatibilist tradition, see above, “Neurosciences and Free Will”.

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have unchangeable political orientations that can be stimulated or amplified by subliminal stimuli. In this light, politicians may tend to work mostly on their appearances and their emotional allure, instead of trying to improve their policy platform and concrete political ideas [59]. Also, if parties based their policies on alleged “scientifically analyzed voters”—whose political and ideological choices were thought to be genetically pre-determined—, they could be tempted to rely on “polls” conducted with fMRIs and pick candidates that, from a neurobiological point of view, would better fit their potential target-voters [60]. There is no reason to think that such conduct would be based on solid theoretical assumptions; certainly, however, if generalized, it might cause a degeneration of the level of political life as such, by reinforcing the idea that only subliminal and emotional factors counts in politics, while rational discourse does not play any relevant role [61]. By the same token, studies on the unconscious, automatic categorization of people according to race and gender may be inappropriately generalized. The idea that innate and deeply rooted neurobiological biases exist regarding racial affiliations could, for example, lead to the choice of not nominating political candidates of ethnic and racial minorities. In this perspective, however, the U.S. Democratic Party should have not nominated Barack Obama to the Presidency, since it should not have been possible for the Caucasian majority to overcome their unconscious bias and vote for him. In general, when the idea that our racial biases are natural and deeply rooted in our nature has been applied in past history (not on the basis of neurobiological findings, of course, but of primordial anthropological or psychological views), it has generally produced socially regressive consequences, by harshly affecting ethnical minorities and their aspirations to social integration and emancipation [62]. Besides the obvious ethical blunders, the mistake shared by those kinds of views (including neuropolitics in many of its forms) is that of taking a real phenomenon—one’s biases in favor of one’s ethnic group—and presenting it, without adequate support, as “brain-wired” by evolutionary selection and, consequently, as automatically elicited. But we know now that education and culture can overcome these biases, notwithstanding how deeply hardwired they are in our brains.

Not so Fast. On Some Bold Neuroscientific Claims Concerning Human Agency

It has to be noted, however, that it is precisely because of the possibility of overcoming our biases (such as our categorization of others in automatic and involuntary ways on the basis of their “races”) that these kinds of neurological investigations can play, if rightly set and presented, a constructive role in our society. A relevant contribution in this sense can derive, for example, by studies that show that people (even well-intentioned people who sincerely try to overcome their prejudices) tend to sympathize with members of their own ethnic group whatever the circumstances are and, in situations of danger or stress, may go so far as to utter racists insults [63]. Indeed, being aware of these unconscious predispositions can help us in improving our behavior and in fighting implicit forms of racism and discrimination. This requires, however, that we accept the idea that culture and education matter, that they can modify our unconscious biases. In general, it is reasonable to think that a “fundamentalist” interpretation of neuroscientific data—one that disregards the importance of history, culture, and societal values by only looking at the causal processes that go from the cerebral to the agential level, ignoring the other way around—seems destined to produce consequences that are more harmful than beneficial. This is a point that becomes particularly clear if one considers social neuroscience, an area in which negative consequences may easily follow when tentative and ungrounded research is taken for granted and used for shaping public policies. For example, in several well-known studies concerning limbic areas, the most ancient from an evolutionary standpoint [64– 68], it has been argued that social dominance and submission relationships are the direct expression of the activation of different areas of the amygdala. In particular, aggressiveness appears to be correlated with the activation of basolateral nodes, while submissiveness seems to be linked to the activation of corticomedial nodes, so that “the more an individual is dominant, the more active his or her basolateral nodes will be; the more submissive, the more active the corticomedial nodes” [69]. In this perspective, a recent scientific treatise [70:ch.2] has defended the efficacy of a cognitive therapy based on role-playing as an “antidote” that, in a psychological setting, reverses the personal—submissive or dominant— inclination of the patient. Nevertheless, the authors state that “in spite of the differences that may emerge

according to the individual subjects or circumstances, the hierarchical position remains at a certain level due to intrinsic self-regulation phenomena (…). It thus seems that the hierarchical position of an individual is difficult to modify” [69]. According to this view, the evolutionary adaptation process has produced a clearly identifiable genetically-based cerebral localization, which can account for the hierarchical structure of society. This view, however, can easily lead to believe that social asymmetries are “natural” and depend on a spontaneously stable equilibrium at the population level.21 Once again, in this perspective the role played by cultural and social phenomena in historical dynamics is deeply undervalued. Moreover, there are good reasons for thinking that if this view was taken for granted—that is, if social policies were modelled on the idea that the existence of social hierarchies is a natural phenomenon—the legitimate quest for emancipation of subordinate individuals and groups would be easily compromised.22 In a similar vein, it has recently been argued that there is a strict correlation between people’s social status and the presence of a copy of the short allele of the 5HTTLPR gene. In particular, some studies have found that this allele is correlated with a reduced gray matter volume in perigenual anterior cingulated cortex (pACC) [71], and that a self-reported social

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It is fair to say, however, that there are also studies that, more prudently, only aim at investigating the cerebral basis of social hierarchies (and remain neutral in the evaluations of the data) or at discovering the neural mechanisms underlying the correlation between low social status and poor health [101–103]. 22 It is important to consider how the investigations on the role that oxytocin plays in the cerebral mechanisms linked to trust are presented to the general public. Sometimes, an overambitious framing of these investigations may lead to the deceptive impression that such a nuanced and decisive component of social interactions can be reduced to the prevalence or lack of a certain neuropeptide. For example, if the experiments carried out with an oxytocin spray (which seems to increase the generosity of individuals exposed to it) are not properly put into context, they may generate the unjustified expectation that we are on the verge of inventing a “kindness pill” [104]. Moreover, in the long term, this attitude could lead to a sort of “neurobiological resignation”, reinforcing beliefs such as that the brain of mistrustful individuals is predisposed to diffidence, and therefore there is no point in trying to change their behavior or that the egoism of uncooperative individuals merely depends on a lack of oxytocin. In that scenario, investments in pharmaceuticals would of course be considered much more effective than the attempts at increasing the trust among the members of a society [105, 106].

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status is specifically correlated with the gray matter volume in that specific region [72]. These studies aim at explaining why individuals with a higher social status live longer and have better health than individuals with lower social status. However, since it has been shown that pACC plays a role in emotions regulation and cognitive control, it has also been postulated that “poor regulatory skills lead to lower social standing—e.g. through drops in social standing based on poor impulse control” [73]. This kind of approach may induce to obliterate, without a solid justification, the relevance of other factors, including the asymmetric distribution of political and economical power, the role of education and the inhibiting role of social biases. However, once assumed as correct, this dubious claim might easily lead to the idea that people who do not manage to climb the social ladder are indeed condemned to their subordinate status by their cerebral structure. In this perspective, it would of course become very difficult to justify any social policy of emancipation. Overstressing the importance of the association between low serotonin level and low social standing [74] may also encourage the pharmaceutical treatment of individuals affected by depression or other conditions caused by low social standings or by specific social and economical conditions, such as a lowpaying, unsatisfactory jobs, unemployment or a unhappy sentimental life. Moreover, the pharmaceutical treatment might also cause the loss of the adaptive contribution of information and motivation given by symptoms of depression. Patients undergoing that treatment adapt themselves to situations which they might otherwise try to change because they would consider them unbearable. A widespread neuroscientific perspective may therefore lead to interpreting mental disorders as strictly individual problems. And this fact can be “be politically regressive. First, it discourages us from seeking social and political solutions to problems. It may be that we could reduce the amount of suffering in a fairer and more effective manner by changing social structures, rather than by medicating individuals” [75:127]. To give another example, the still unproven claim, discussed above, that the cerebral component is dominant in explaining aggressive behavior [42] might lead to the conclusion that a better education would not be of any help for aggressive teenagers, on the one hand, and to social control strategies, on the

other hand, and more specifically to strategies that rely on the administration of psychoactive drugs to youths identified as violence-prone by neurobiological investigations [76:ch.1]. It has also been argued that the control of personality and the levelling out of individual differences (provoked by the widespread use of psychoactive drugs) could lead to the emergence of a “euphoric” and “carefree” psychological profile. This profile could cause a reduction in the variety of personality styles and behaviors, which are key assets for economic, social and cultural development [77]. It has been stressed above that with regard to our political, and specifically electoral, tendencies great caution should also be exercised before announcing the alleged “automaticity” of our reactions linked to the racial categorisation of individuals. This is a claim that can be generalized to all forms of social interactions. Many studies have shown that white subjects who react negatively when presented with black faces show an increase in the activity of the amygdala—an area linked to emotive reactions, particularly fear [78, 79]. Although investigating the cerebral correlates of racial prejudice is certainly important, the interpretation of the related findings is extremely complex, and the inferences drawn from this kind of research may be easily misleading. Arguing that racial “diffidence” is somehow immediate and cannot be suppressed could lead to the justification and/or tolerance of discriminatory attitudes. Furthermore, it has not been proven that the increased activity of the amygdala is innate: it could instead be the result of a deep internalization of social prejudice in the early years of an individual’s life. Indeed, much broader studies, with more complex experimental designs, are needed in order to draw plausible general indications in this area. Finally, scientific articles like the above-mentioned “Love: Neuroscience reveals it all” [41]—according to which falling in love is nothing more than a matter of hormones and neuropeptides—may easily strengthen (also in virtue of their appealing titles) very questionable beliefs, such as that serial cheaters or bad parents may be excused by particular genetic variants or that, in principle, all sentimental problems could be solved by using drugs that reinforce the relevant neuropeptides. Indeed, there is still plenty of reasons for supposing that, in affective relationships, biographical, cultural and social factors (whose variety at this time certainly cannot be accounted for in generic

Not so Fast. On Some Bold Neuroscientific Claims Concerning Human Agency

terms are) (at least) as relevant as the innate neurobiological inclinations. Therefore, at least at this stage, there is no reason to believe that love is a merely physiological phenomenon. However if, in spite of this lack of justification, the neurobiological view of love became common wisdom, unwelcome consequences may easily follow. For example, people who are keen to exploit others (sexually or emotionally) could be induced to restrain themselves even less and offer some “just so” neurobiological stories in order to justify their misconducts.

Conclusion As Paul Wolpe stated, “science has become one of the most powerful and pervasive forces for change in modern societies. As the professionals at its helm, scientists have a unique responsibility to shepherd that change with careful ethical scrutiny of their own behaviour and thoughtful advocacy of scientific research” [80]. In this paper, we have tried to highlight some relevant problems in the applications of neurosciences to the study of human agency. As said, in the background of those applications, often there is the ideal that explaining how the brain works is the key method—if not (at least potentially) the only correct method—to account for the human mind in all its facets, and also for reaching adequate social explanations and political prescriptions. We have argued, first, that, at least for what we know at this stage about the neural correlate of human agency, such an ideal is overly optimistic and frequently generates conceptual confusion, misinterpretations of the empirical data and, in some cases, even regressive consequences at the social and political level. It may be useful to repeat that we are not disputing the usefulness, even less the legitimacy, of the applications of neurobiology to the study of the human mind. On the contrary, there is absolutely no doubt that these applications are vastly successful. Our aim here has only been to suggest that, when one comes to the issue of human agency, great caution should be used before drawing bold philosophical, political and social conclusions from neurological findings, whose correct interpretation and value are still extremely controversial. Indeed, there is plenty of excellent reasons for believing that neurobiology will continue to enrich our understanding of many features

of the human mind, but there are no good reasons for thinking that it is going to fully explain them all.

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