Project Proposal. Sophie Tate ... investigate certain linguistic phenomena called “
null arguments” by employing ... Some examples of these are the N400.
Summer Research 2008 Project Proposal
Sophie Tate Department of Psychology March 28, 2008
St. Mary’s College of California
The Electrophysiological Evidence of the Processes of Null Arguments in English Speakers
With the guidance of Dr. Hiroko Nakano of the Psychology department, I plan to investigate certain linguistic phenomena called “null arguments” by employing electroencephalographic (EEG) techniques. The specific technique that we will utilize in our project is the recording and analysis of Event Related Potentials (ERPs). ERPs are brain wave patterns that change depending on the nature of sensory stimuli. ERPs have been useful tools in the investigation of human cognitive processes. They are especially helpful in looking at the millisecond-level of mental processing patterns. There are some ERP components that are especially useful in the investigation of cognitive processes with linguistically related stimuli. These components comprise either a negative or positive deflection of waves (N or P) and a number of milliseconds at which the peak of the wave is elicited after the onset of the stimulus. Some examples of these are the N400 (negative going wave peaking at around 400 ms. after the onset of the stimulus), which indicates semantic or meaning related integration difficulty; and the P600 (positive going wave peaking at around 600 ms. after the onset of the stimulus), which indicates syntactic or structurally related integration difficulty. The specific component that we will be employing is the Omitted Stimulus Response (OSR), (also called Omission Potential (OP)). The wave pattern of the OSR occurs at or around 300ms post onset stimulus with a positive deflection. The OSR seems to reflect a cognitive response to an event of the omission of an expected piece of stimuli. The OSR has been investigated extensively with both visual (light) and auditory (tone) stimuli (Busse & Woldorff, 2003; Penney, 2004). For instance, if a very periodical series of sensory stimuli (e.g. flashes of light) are presented, and then a flash of light is occasionally omitted, an OSR is likely to be elicited when people “see” an omitted light (Penney, 2004). Our main research question is the effectiveness of Omitted Stimulus Response with omissions in linguistic stimuli (as opposed to “light” or “tones”). We are interested in eliciting significant OSRs with grammatically deviated stimuli, namely null arguments. A null argument St. Mary’s College of California
is a verb argument (a subject or object noun) that is omitted in a sentence. For example, when we describe the situational context “I left my coffee cup on the counter, but now it’s gone”, a following sentence with a null argument occurs in Japanese: “Did you move [null]?” or even simply “[null] move [null]?” Please note that an object noun and a subject noun are covert in these sentences. Understanding what the null argument refers to relies on the context of the previous statement. The use of null arguments is linguistically legal in Japanese, however, not in English. In English, the arguments are always overt, so the following sentence would ask, “Did you move it?” Null arguments have been found to be used in early childhood cross-linguistically (Guerriero, Oshima-Takane, & Kuriyama, 2006) but are gradually replaced with overt arguments over time among English speakers. However, among Japanese speakers the usage of null argument is grammatically correct and is continued into adulthood as part of normal usage (Guerriero et al., 2006). Our proposed hypothesis is that if null arguments are presented to adults who speak English as a first language, OSRs will be elicited because overt expressions of arguments are expected in English grammar. If we obtain OSRs with null arguments, it is scientifically meaningful because it indicates that the cognitive processes of the language material have something common with the processes of a sequence of tones or flashes of light, despite the fact that language involves “contextual meaning” while light and tones do not. No studies to date have investigated OSRs with linguistic material, to our knowledge. If this study shows evidence of OSRs in English speakers, it is also exciting because in the future, we will be able to extend the study with people who speak Japanese, Spanish, or Italian (all of which allow null arguments), and to cross-linguistically investigate cognitive processes of grammar and context. We will also be able to extend the study to test children in a language environment that allows or does not allow null arguments, and to investigate human cognitive development. I would like to conduct the experiment using auditory material (as opposed to visual) because “speech” is a natural language property. I have learned how to digitally record speech and how to edit audio files in Dr. Nakano’s Sensation and Perception course and would like to employ this new skill to create experimental materials used in this project. I plan to construct a series of audio files of sentences with/without arguments (e.g. “My coffee cup was on the counter.” (context sentence), “Did you move [null]” (test sentence), and St. Mary’s College of California
“Did you move it?” (control sentence). English speakers would listen to these sentences while their EEG is recorded. My prediction is that the participants would elicit larger positive going waves around 300 ms after the onset of the object argument for the test condition (null) compared to the control condition (overt). This is potentially the OSR with the presentation of null arguments. I plan to test around thirty participants, all adults who speak English as their first language. This study would potentially act as a study that would be used as foundational material for a larger grant proposal and subsequent research study with Dr. Nakano and Dr. OshimaTakane at McGill University. I am very excited about the opportunity to discover more about the relationship between language and the human brain and appreciate the chance to be considered.
References Busse, L. & Woldorff, M.G. (2003). The ERP omitted stimulus response to “no-stim” events and its implications for fast-rate event-related fMRI designs. NeuroImage. 18, 856-864. Guerriero, S.M., Oshima-Takane, Y, & Kuriyama, Y. (2006). The development of referential choice in English and Japanese: a discourse-pragmatic perspective. Journal of Child Language. 33, 832-857. Penney, T.B. (2004). Electrophysiological correlates of interval timing in the Stop-ReactionTime task. Cognitive Brain Research. 21, 234-249.
St. Mary’s College of California
