Experimental Aging Research, 30:75–94, 2004 Copyright # Taylor & Francis Inc. ISSN: 0361-073X print/1096-4657 online DOI: 10.1080=03610730490251496
The Time Course of Metonymic Language Text Processing by Older and Younger Adults Heather E. Humphrey and Susan Kemper University of Kansas, Lawrence, Kansas, USA
Jeffrey D. Radel University of Kansas Medical Center, Lawrence, Kansas, USA The influence of aging on the processing of figurative language was investigated by utilizing Frisson and Pickering’s (Journal of Experimental Psychology: Learning, Memory, and Cognition, 25, 1366– 1383, 1999) paradigm, monitoring eye fixation times to target words in sentences. First fixation times and total fixation times were analyzed for familiar and unfamiliar metonymies and literal control sentences. Frisson and Pickering found that processing figurative and literal expressions yielded similar patterns of eye fixations. In the current study, these methods and results were replicated and extended to include older adults’ processing of metonymies. This investigation replicated their findings for young adults and found that older adults produced the same processing patterns as the younger adults.
Received 20 April 2001; accepted 2 February 2003. This study was supported by a grant from the National Institute of Aging (NIA grant AG00226) to the Research Training Program in Communication and Aging at the University of Kansas. The author thank especially everyone at the Grayhawk Laboratory, including Dr. Joan McDowd, Valorie Wells, and the Grayhawk participants as well as the Occupational Therapy research assistants Connie Smith and Connie Rose. In addition, the authors thank the reviewers for their helpful comments. All stimuli are available through the first author upon request. Address correspondence to Susan Kemper, Department of Gerontology, Human Development Center, 1000 Sunnyside Avenue, Room 3090, University of Kansas, Lawrence, KS 66045, USA. E-mail:
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If a language-processing theory is to be useful, it must be able to predict how language processing changes over the life span as well as account for the processing of all types of language, including nonliteral language such as parables, idioms, metaphors and metonymies, as well as sarcasm and irony. Few studies have been conducted into figurative language processing by older adults. We will review these and then propose our experiment focused on a type of figurative language processing: metonymy. Initial studies of figurative language processing by older adults asked individuals to explain metaphors. Boswell (1979) asked older and younger adults to explain four metaphors such as ‘Slavery is the world’s frost.’ Results indicated that older adults were less specific than younger adults and used more ‘poetic’ explanations, such as ‘‘Like frost to the gardener, slavery has continued to plague man’s cultural efforts through the ages,’’ than the younger adults who used more literal explanations, such as ‘‘Slavery is cold and it’s cruel. When I think of going out in the frost I just dislike it very much.’’ She concluded that older adults use a more synthesizing form of processing whereas younger adults focused on more specific aspects of the metaphors. In contrast, an attempted replication of Boswell (1979) by Kramer and Woodruff (1984) did not yield similar results. Kramer and Woodruff found no differences among older and younger adults in the degree to which they provided an integration of concepts related to the metaphor. Their study included a mean young adult age of 27.5 (range 19 to 34) compared to Boswell’s mean young age group of 18 years old (range 17 to 19), concluding that adults beyond adolescence do not differ in ability to integrate aspects of metaphors. Szuchman and Erber (1990) questioned the metaphors used in both Boswell (1979) and Kramer and Woodruff (1984) and the rating scales employed. Szuchman and Erber (1990) asked participants to make up a story that could explain the metaphors such as ‘death waves a pale flag.’ Independent raters gave both older and younger adults a higher poetic score for unusual metaphors (‘slavery is the frost of the world’) than for the ordinary metaphors; however, no age differences were found. Due to the lack of consistency in results, no decisive conclusion can be drawn on the basis of these studies regarding metaphor explanation by older adults in everyday language. Light, Owens, Mahoney, and LaVoie (1993) conducted five experiments in the area of metaphor processing by older adults. Over the course of conducting these experiments, different methodologies were used, resulting in differential effects for younger and older adults. In the first three experiments, Light et al.’s results indicated that older adults performed equally as well as younger adults in understanding metaphors. In experiment one, Glucksberg, Guildea, and Bookin’s (1982) Metaphor Interference Task was employed. Glucksberg et al.
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found that the metaphoric interpretation of an expression interferes with the literal ‘false’ decision, indicating figurative meanings are automatically accessed. Further, if older adults are not sensitive to the metaphoric meaning, the metaphor interference effect should be reduced, if not eliminated. However, older adults showed a similar interference effect to that of the younger adults. Experiment 2 was conducted to ascertain how difficult the metaphors were to interpret. Both older and younger adults tended to find nonscrambled metaphors easier to interpret than scrambled metaphors. A property verification task was used in the third experiment. Novel metaphors were constructed to investigate older adults’ ability to derive figurative meanings. Older and younger adults were asked to judge whether a sentence was true or false based on a previous metaphor or simile. The results indicated that older adults were equally capable of using the particular properties of words to comprehend either a literal or a figurative expression. In summary, the first three experiments were similar in that indirect measures of figurative language comprehension were utilized and no age differences were found. In Experiments 4 and 5, age differences were observed. These two experiments directly tested the ability to interpret metaphors. In Experiment 4, older adults recalled fewer metaphors when given cues related to the metaphor. Experiment 5 was a production task in which participants were asked to produce properties of nouns used in metaphors. The oldold (71- to 82-year-old) adults tended to produce a property related to the literal noun rather than properties related to the metaphor relationship. From these experiments, it is difficult to conclude that older adults perform differently than younger adults regarding figurative language comprehension. Other factors, such as response demands and task instruction, seem to influence results more than the contrast between literal and nonliteral language. Gregory and Waggoner (1996) also compared direct and indirect tasks of metaphor interpretation by younger and older adults. The indirect task required the participants to make a choice regarding the emotion suggested in the passage, whereas the direct task involved writing an explanation of why they selected the particular emotion. The results from the indirect task coincided with Light et al.’s (1993) indirect tasks of the first three experiments. Older adults’ comprehension of metaphors was similar to younger adults’. Also corresponding with Light et al.’s results, Gregory and Waggoner found production differences among older and younger adults in a direct task of metaphor interpretation. The older adults tended to provide story-based explanations for their interpretations as compared to a succinct explanation of the metaphor’s relationship to the emotion. It is difficult to draw any firm conclusions based on the collective results of these experiments. Abstract reasoning, conceptual relationships
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and structures, word associations and word meanings, as well as sense creation must be utilized in order to understand figurative language. The collective results of previous research indicate that older and younger adults utilize the same conceptual relationships and word associations when processing metaphors. Yet, older adults may interpret figurative expressions in an overly abstract fashion (see Light, 1991; Light et al., 1993; Gregory and Waggoner, 1996; Zelinski & Hyde, 1996). A possible explanation for age differences in figurative language interpretation comes from Hasher and Zacks (1988). They suggest that older adults’ inhibitory mechanisms may weaken with age, which in turn permits the intrusion of personal associations. These personal associations could be why older adults show a tendency for elaborative stories as in Gregory and Waggoner (1996) or in the production of less specific metaphor-relevant properties in Experiment 5 conducted by Light et al. (1993). A similar mechanism for nonliteral language comprehension has been proposed by Gernsbacher and Robinson (1999). Another possibility for age differences in figurative language interpretation, suggested by Light et al. (1993), is that task demand may differentially affect younger and older adults. One contrast they raised is that of direct measures, such as producing metaphor properties, and indirect measures, such as acceptability judgments. A second contrast concerns the time course of processing. On-line measurements such as word-byword reading times may be more sensitive to processing differences between literal and figurative language than off-line measures such as recall. Yet, on-line measures may interfere with normal reading. An on-line measure that does not interfere with normal reading and is sensitive to the moment of processing may be able to solve these inconsistencies with the diversity of methodologies. One such tool is recording eye movements during normal reading situations. Eye-tracking methodology has been successfully employed to investigate many reading and language phenomena in younger adults (Rayner, 1999). In addition to on-line versus off-line issues, eye-tracking methodology removes the occurrence of motor-response declines. Although some aspects of vision such as visual acuity (Schieber & Baldwin, 1996) decline with age, other aspects such as fixation stability (Kosnick, Kline, Fiker, & Sekuler, 1987) and oculomotor control (Abrams, Pratt, & Chasteen, 1998) show little change. Eye tracking seems well suited to study figurative language in both older and younger adults. It enables researchers to obtain precise measurements of the allocation of processing resources during the immediate processing of the target word while removing any motor component deficits that accompany the aging process. Although some information exists regarding metaphor comprehension in older adults, nothing is known about the immediate on-line processing of figurative language by older adults.
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The following experiment was conducted to investigate the time course of figurative language processing by older and younger adults replicating Frisson and Pickering (1999). Frisson and Pickering used a type of figurative language referred to as metonymy. Consider ‘The White House issued a press release’ or ‘I love the new Matisse at the gallery’ are not literally true. The White House is a building and Matisse was a painter. Metonymies convey meaning by referring to one salient feature of an object or an entity in order to evoke a general situation or event. The salient feature is taken as standing for another feature in the same schema or for the schema as a whole. The first goal of the experiment was to replicate the figurative language processing results found by Frisson and Pickering (1999) with younger adults. They found similar processing times for figurative and literal metonymic nouns, supporting a parallel model of figurative language processing. ‘‘Parallel processing’’ models (Hobbs, 1983) or ‘concurrent processing models’ (Gerrig & Healy, 1983; Ortony, Schallert, Reynolds, & Antos, 1978; Thibadeau, Just, & Carpenter, 1982) presume that both meanings are derived simultaneously and the contextual cues are used to select the appropriate meaning and inhibit the inappropriate meaning. There is an extensive record of research (Cacciari & Glucksberg, 1994; Gibbs, 1994) evaluating various processing models. In general, evidence favors the ‘figurative first’ model for familiar metaphors, idioms, and proverbs. This model assumes conventional meanings are stored in the lexicon and can be rapidly accessed, therefore the figurative meaning is processed prior to the literal meaning. There is no consensus regarding the processing of novel or unfamiliar figurative expressions. The second and main goal of the experiment was to investigate older adults’ figurative language processing. If older adults have difficulties in interpreting metonymies, either familiar or unfamiliar, processing times for the familiar figurative target condition should exceed those for familiar literal controls. Thus, both younger and older adults should have longer processing times in the figurative context condition if the literal interpretation is processed first and a reanalysis is required to determine the figurative meaning, supporting a literal first processing model. ‘Literal first’ processing models (Dascal, 1987; Grice, 1975; Searle, 1979) presume that in order to comprehend nonliteral language, people first must process the literal meaning of the language. If a discrepancy with the context is detected, the literal interpretation must be inhibited and a nonliteral meaning inferred. An ‘error recovery’ model using sense creation and sense selection also fits into the category of a literal first model (Forster, 1979; Gerrig & Healy, 1983). Sense creation only occurs after all other possibilities are rejected (i.e., literal meanings) as inappropriate.
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METHOD Participants Twenty-five younger adults and 33 older adults participated in the study. All were native English speakers screened to exclude health and vision impairments. The younger adults were recruited from a large midwestern university community by posted signs as well as other announcements and were paid $10.00 each for participating. The older adults were recruited from a registry of previous research participants and were paid $10.00 plus travel expenses. The younger adult group ranged in age from 21 to 30 years (M ¼ 24.3 years; SD ¼ 2.4 years) and consisted of 22 females and 3 males. The older adult group ranged in age from 65 to 83 years (M ¼ 74 years; SD ¼ 4.1 years) and consisted of 18 females and 16 males. The two groups differed in terms of years of education, F(1, 45) ¼ 4.32, p < .045, (MY ¼ 15.6, SDY ¼ 3.2; MO ¼ 17.8, SDO ¼ 4.1), but self-reports of vision and the number of hours spent reading did not differ.
Apparatus A computer monitor (14-inch resolution RGB monitor) was used to present the stimuli. Participants who used corrective lenses for reading used them while participating in the experiment. Text was presented in Courier 22 point font and appeared as black letters on a light blue background with a mean size for individual letters of 0.3 of visual angle. Ambient lighting in the room was approximately 1 lx and computer screen brightness varied between 10 and 30 lx with a screen brightness adjusted to produce a 3- to 4-nm diameter pupil when viewing a single target dot located at the center of the presentation screen. Viewing was binocular. Only the right eye was illuminated by an array of 6 infraredemitting diodes (880 nm, 16 MW each) and the eye movement was recorded by a low-light, high-resolution CCD video camera (Panasonic WW-BP314) and a long focal length, high-magnification lens (Infinity Photo-Optic HDF 0.25 to 2.25 lens). The boundary of the pupil was identified by the tracking system (ISCAN model RK-416) at a sampling rate of 90 Hz using contrast detection. The intersection of the vertical and horizontal axes determined the center of the pupil. Changes in eye position were recorded by tracking movements of the intersection point. A computer (Macintosh Quadra 840 AV) equipped with hardware and software (GW Instruments MacADIOS and SuperScope II) was used for data collection and analysis.
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Participants were positioned for individual comfort in an adjustable chair with head support and a chin guide to reduce artifact data due to head movement while completing the experiment.
Materials and Design The design was a 2 (age) 4 (stimuli list) 2 (metonymy familiarity) 2 (context) mixed analysis of variance (ANOVA), with familiarity and context as repeated measures and age and stimuli list as a between-group factor. Frisson and Pickering’s (1999) place-for-institution metonymies were used in the experiment. They conducted plausibility norming and predictability completions with 91 participants who did not participate in the eye-tracking portion as well as assessed the frequencies using the British National Corpus. Modifications were made to account for differences in British English and American English usage. For example, in the sentence, ‘. . . husband ran to the platform’ we substituted the word ‘driveway’ for platform as train platforms may not be as familiar in the United States. Whereas Frisson and Pickering asked comprehension questions randomly on 50% of the trials, during the current experiment, a comprehension question followed every sentence probing for either figurative or literal processing of the sentence. We assumed that the answers to the probe questions reflected acceptability of the figurative language and deemed it necessary to evaluate all of the types of sentences. Participants saw a total of 58 sentences: 10 practice, 16 experimental, and 32 filler sentences. Filler sentences were identical across all stimuli lists. The filler sentences included the place-for-event sentences created by Frisson and Pickering (1999) as well as additional ones created to match the experimental sentences in structure. The stimuli sentences were formed by combining nonliteral and literal contexts with familiar and unfamiliar metonymies (Table 1). Four stimuli lists were created so that each participant only saw one version of experimental sentence, but within each list, examples of all four types of stimuli sentences were presented. A comprehension question accompanied each practice, filler, and experimental sentence. Each list was constructed with 1 practice block of 10 sentences and questions and 4 experimental blocks containing 12 sentences and questions each. Each block contained one example of each type of sentence. The target noun metonymy always appeared at the end of the first line of text (see Table 1) to facilitate identification of the corresponding eye position. The question paired with each experimental sentence probed for either the appropriate literal or figurative interpretation. A ‘yes’ answer to the question indicated that the participant was processing the sentence as intended, either literally or figuratively. Filler questions were answered
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Inferential
Filler
Unfamiliar metonymy
Familiar metonymy
Control for unfamiliar metonymy
Control for familiar metonymy
Language
Note. A ‘‘=’’ denotes end of presentation line.
Factual
Filler
Figurative
Experimental
Figurative
Literal
Experimental
Experimental
Literal
Context
Experimental
Type
This morning the terrorists blew up the prison=in order to gain publicity for their cause. Did the terrorists destroy the complex? This morning the terrorists blew up the statue=in order to gain publicity for their cause. Did the terrorists destroy the statue? The representatives negotiated with the prison=to make their point a bit clearer. Did the representatives negotiate with the warden? The representatives negotiated with the statue=in order to make their point a bit clearer. Did the representatives negotiate with the art owner? The guide gave us an excellent tour around San Francisco=and the he recommended a delightful restaurant. Did the guide recommend a cozy hotel? The children painted for several hours=before they played ball. Did the children for several hours before they went outdoors?
Sentence and Question
YES
NO
YES
YES
YES
YES
Answer
TABLE 1 Examples of Familiar and Unfamiliar Metonymies, Literal Controls, and Factual and Inferential Questions. Target words are in Italics
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with both yes and no responses; across all sentences participants encountered an equal number of possible yes and no questions.
Comprehension Check The filler and practice questions included factual and inferential questions (see Table 1). There were 32 factual and 10 inferential questions. Participants were required to answer 80% of the factual questions correctly to be included in the analysis. One young adult and no older adults failed to meet this criterion. The 10 inferential questions were not analyzed due to the inability to assess the different possible interpretations from our forced choice yes=no response available to the participant. Overall, young and older adults did differ somewhat in comprehension, F(1, 45) ¼ 4.41, p < .05 (MY ¼ 29.74, SDY ¼ 1.45; MO ¼ 28.74, SDO ¼ 1.76). In order to verify the interrelation of the metonym and all modifications to British English usage, an independent group of participants evaluated the experimental materials. Thirty young students answered yes or no questions about the filler and experimental sentences. None participated in the eye movement experiment. Four booklets were created; each contained one version of each experimental sentence interspersed among 25 fillers. If participants answered yes to the probe question ‘Did the woman thank the cashier?’ in response to the sentence ‘The grateful woman thanked the store which really was a nice gesture by her’ the assumption can be made that the noun store was understood metonymically as standing in for the noun cashier. A ‘yes’ answer from 75% of the participants was required for all figurative and literal metonymies used in the eye movement experiment.
Experimental Procedure The testing session lasted approximately 45 min. Participants first read and signed the consent form then completed the demographic and health questionnaire. Participants were tested individually while seated approximately 41 cm from the computer screen. Following a horizontal calibration procedure, the participants read 10 sentences presented one at a time in decreasing font size to test their acuity from a 20-inch (approx 51 cm) focal distance. After the acuity check, the instruments were calibrated a second time. The practice and experimental blocks were then presented. On each trial, a blank screen was presented for 1 s, followed by a fixation dot in the center of screen for 2 s. The sentence was
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automatically presented to the participant and he or she was allowed to control his or her reading time by using a computer mouse to trigger the presentation of the question; the participant answered the question orally, the experimenter recorded the answer and initiated the next trial. Participants were instructed to read the sentence silently for comprehension, push the mouse button to advance to the question screen, and then answer yes or no orally to each question. They were asked to read the sentence only one time and asked not to reread the sentence. The participants were informed that there were no ‘trick’ questions and were to answer spontaneously as if someone just walked up to them and asked them the question. After the practice trials, each participant was instructed not to worry if they felt they couldn’t answer some of the questions or if the sentence seemed to ‘not make sense,’ but just to respond with their first answer. They began with a practice block with 10 sentences and 10 questions. After the practice block, they were informed there were 4 experimental blocks of sentences and that they could close their eyes, rest, or both if they felt fatigued after each block of sentences. No feedback was given during the experimental blocks. After completing the experiment, the participants were debriefed; all questions were answered at that time. Eye movements to both the sentences and the questions were recorded. For single word fixations, a first fixation duration (Inhoff, 1984), gaze duration, single fixation duration (Rayner, Sereno, & Raney, 1996), first-pass regressions (Frisson & Pickering, 1999), and total fixation duration (Rayner, 1999) times can be collected and analyzed. The region of interest in this experiment was the single-noun metonymy or the literal controls presented as the last word on the first line of the sentence. For this experiment, the first fixation and total fixation time to the target words of the experimental sentences were used in the analysis. Four separate analyses were performed. Initially, first fixation and total fixation times were analyzed for all experimental sentences. Subsequently, the first fixation and total fixation times for target words were reanalyzed only for those experimental sentences for which the participant responded with a ‘yes’ answer to the paired probe question. In addition, a follow-up analysis examined log-transformed fixation times following the recommendation of Faust, Balota, Spieler, and Ferraro (1999).
RESULTS Ten older adults were excluded from the analysis (5 due to interference from the position of their bifocal lens, 1 had a scotoma where the target word appeared, 1 had a head tremor, 3 were unable to perform the task). Data that were lost due to tracking difficulties (0.089%) was replaced
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with the participants condition mean. Two younger adults were excluded due to excessive machine tracking errors in the target noun area (< 20%) and failure to meet comprehension criteria. Eye fixations less than 80 ms and more than 1500 ms were excluded from the analysis and replaced with the condition mean (one data point). After all exclusions were made, data from 23 younger adults and 23 older adults’ were included in the analyses. Separate analyses were performed for first fixations and total fixation times and are reported below. In each case, raw fixation times were analyzed as well as log transformations of the fixation times. In general, the data from the first fixation time were not sensitive to the manipulation of context and familiarity. Only the results from the measure of the total fixation time are reported.
Total Fixations: All Data Total fixation times include all fixation times and regressive eye fixations. Total fixation time data were analyzed in a 2 (age) 4 (stimuli list) 2 (metonymy familiarity) 2 (context) mixed ANOVA and are summarized in Figures 1 and 2. Both the younger and older adults’ total fixation times closely resemble those found by Frisson et al. (1999) and are shown in Table 2. The main effect of context was significant, F(1, 44) ¼ 8.99, MSE ¼ .001, p < .004. However, this effect was qualified by the interaction between context and metonymy familiarity, F(1, 44) ¼ 7.80, MSE ¼ .001, p < .008. None of the between-subject effects or interactions were significant, p > .1; the data were then collapsed across groups.
FIGURE 1 Mean fixation times (and SEs ) for familiar and unfamiliar metonymies and their literal controls for young and older adults.
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FIGURE 2 Mean fixation times (and SEs ) for familiar and unfamiliar metonymies and their literal controls for all participants regardless of accuracy of answers to probe questions.
Paired comparisons revealed no significant differences between the two types of literal controls, t(45) ¼ 1.239, p > .05. Unfamiliar metonymies in figurative contexts were fixated on longer than familiar metonymies in figurative contexts, t(45) ¼ 3.033, p < .05, supporting Frisson and Pickering (1999). Unfamiliar metonymies in figurative contexts were also processed more slowly than their literal controls, t(45) ¼ 3.841, p < .000. Further, there was a significant difference between unfamiliar metonymies in figurative contexts and the other three conditions comTABLE 2 Mean Total Fixation Times in Milliseconds for the Target Words for Younger and Older Adults: All Data (Standard deviations in parentheses) Condition Literal context for familiar metonymy Literal context for unfamiliar metonymy Figurative context for familiar metonymy Figurative context for unfamiliar metonymy
Younger (n ¼ 23) Older (n ¼ 23) Frisson et al. (1999) 385 (129)
429 (234)
430 (131)
69 (122)
388 (154)
437 (146)
385 (137)
446 (151)
445 (472)
442 (135)
518 (185)
776 (336)
Note. Frisson et al. (1999) N ¼ 28 young adults.
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bined, t(45) ¼ 3.937, p < .000, indicating that unfamiliar metonymies in figurative contexts are processed more slowly than the other types of sentences. Cohen’s ‘d’ was calculated with results, indicating effect sizes of .423 and .469 for the conditions figurative context with a familiar metonymy and figurative context with an unfamiliar, respectively. The data were then subjected to a log transformation. The transformed total fixation times include all fixation times and regressive eye fixations. Total fixation time data were analyzed in a 2 (age) 4 (stimuli list) 2 (metonymy familiarity) 2 (context) mixed ANOVA. The main effect of context was significant, F(1, 44) ¼ 10.637, MSE ¼ .017, p < .003. However this effect was qualified by the interaction between context and metonymy familiarity, F(1, 44) ¼ 9.123, MSE ¼ .009, p < .005. The between-group factor was not significant nor were any of the interactions with this factor, all F < 1, p > .10.
Total Fixation: Correct Answer Total fixation times were reanalyzed for those trials on which participants gave a ‘yes’ response to the probe question. The data were analyzed in a 2 (age) 4 (stimuli list) 2 (metonymy familiarity) 2 (context) mixed ANOVA and are summarized in Figure 3. Group means appear in Table 3. Eight younger and 12 older adults were excluded from this analysis as they failed to provide at least one ‘yes’ response to a probe
FIGURE 3 Mean fixation times (and SEs ) for familiar and unfamiliar metonymies and their literal controls for all participants for probe questions answered correctly.
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TABLE 3 Mean Total Fixation Times in Milliseconds for the Target Words (Standard deviations in parentheses)
Condition Literal context for familiar metonymy Literal context for unfamiliar metonymy Figurative context for familiar metonymy Figurative context for unfamiliar metonymy
Collapsed across groups
Target word with correct answers to probe question
407 (188)
421 (212)
378 (138)
368 (133)
416 (146)
438 (248)
480 (165)
532 (272)
Note. N ¼ 48 for Collapsed groups. N ¼ 26 for Target word with correct answer to probe question.
question for all four conditions. Five young and 12 older adults rejected all four unfamiliar metonymies in literal and figurative contexts. The results from the answer-dependent analysis were equivalent with two exceptions. A marginal interaction of context by metonymy familiarity was found, F(1, 24) ¼ 3.92, p < .059; the data were then collapsed across groups. There were no significant differences between the two control conditions, t(25) ¼ 1.301, p > .05, between the familiar metonymies in figurative contexts compared to literal controls, t(25) ¼ 1.027, p > .314, or between familiar or unfamiliar metonymies in figurative contexts, t(25) ¼ 1.480, p > .150. However, there was a significant difference found for unfamiliar metonymies in figurative contexts and the other three conditions combined, t(25) ¼ 2.283, p < .05. This pattern of results indicates that familiar metonymies are processed as rapidly as the literal controls, whereas unfamiliar metonymies are processed more slowly than other types of sentences. As in the previous analysis, the data were then subjected to a log transformation. Similar results were found with one exception the context by metonymy familiarity interaction was marginal, F(1, 24) ¼ 4.05, p < .056.
Answers The number of correct answers per condition was analyzed in a 2 (metonymy familiarity) 2 (context) 2 (age) 4 (stimuli list) mixed ANOVA and are summarized in Figure 4. Significant main effects of context, F(1, 44) ¼ 27.98, MSE ¼ .723, p < .000, and familiarity were found, F(1, 44) ¼ 18.98, MSE ¼ 1.07, p < .000. These were qualified by a significant interaction of context by familiarity, F(1, 44) ¼ 7.264, MSE ¼ .917,
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FIGURE 4 Mean number (and SEs ) of probe questions answered correctly by young and older participants.
p < .01. The between-group main effect of age was significant, F(1, 44) ¼ 8.00, p < .007. Both younger and older adults tended to reject unfamiliar metonymies used in figurative contexts as compared to literal contexts, t(45) ¼ 5.598, p < .000. To assess the acceptability by both age groups of the stimuli further, paired comparisons were conducted. They indicate that both younger and older adults find both types of literal controls to be equally acceptable, t(22) ¼ 1.182, p > .25, and t(22) ¼ 1.266, p > .21, respectively. Older adults found familiar and unfamiliar metonymies less acceptable than their respective controls, t(22) ¼ 2.806, p < .01, and t(22) ¼ 2.522, p < .02, respectively, as compared to younger adults.
Reading Times Reading times for the filler sentences for all participants were analyzed with a t test. No significant main effects of age, t(44) ¼ .275, p > .1 were found. The reading times of the participants that were included in the Total Correct analysis were also compared as well as participants that were not included in the Total Correct analysis. Figure 5 illustrates no age differences in reading times for the participants included in the total correct analysis, t(18) ¼ .165, p > .1, as well as no age differences for the participants who were not included in the Total Correct analysis, t(24) ¼ .308, p > .1. The amount of time both younger and older adults spent reading the sentences did not affect the answers they gave to the probe question. This analysis also indicates that older adults were reading at a similar pace as the younger adults, thus increasing the confidence
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FIGURE 5 Mean Reading Time (and SEs ) for young and older adults included and excluded from the final analysis.
that effects found for older adults are not due to a general slowing process.
DISCUSSION This experiment extended the research of Frisson and Pickering (1999) to compare younger adults and older adults’ eye movements while reading literal and figurative expressions. First fixation times and total fixation times were analyzed for familiar and unfamiliar metonymies and literal control sentences. Unlike Frisson and Pickering’s findings, first fixation times in this study were not sensitive to literal versus figurative usage. However, total fixation times revealed processing differences between literal and figurative language. Based on the total fixation times, unfamiliar metonymies were read more slowly than familiar metonymies and more slowly than their literal controls, replicating the main finding of Frisson and Pickering. This experiment employed a second series of analyses. Although Frisson and Pickering (1999) included comprehension probes in their experiment, they report no analyses contingent on the probes. The probes were included in this experiment to verify that the readers had interpreted
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the figurative expressions as intended. Many did not. Consequently, the first fixation times and total fixation times were reanalyzed using only trials in which the participant’s responses to the probe were consistent with the intended figurative or literal meaning. Using this more conservative analysis, unfamiliar metonymies were again fixated longer than the other types of expressions when total fixation times were considered. Further, fixation time of familiar metonymies and in the literal controls were similar. As in the initial analysis, first fixation times were not sensitive to processing literal versus figurative language usage. The data were also subjected to a log transformation to control for possible age differences in speed of processing, following Faust et al. (1999). In these analyses, the interaction of context and familiarity was somewhat reduced but confirmed the analysis of the untransformed total fixation times. These results must be considered in light of the current debate concerning figurative language processing. If a literal processing model is correct, both familiar and unfamiliar metonymies should be processed more slowly than their literal controls. The results suggest such a model is incorrect. Although unfamiliar metonymies were processed more slowly than their literal controls, familiar metonymies were not. The results support a parallel language-processing (Hobbs, 1983) model or a ‘concurrent processing model’ (Gerrig & Healy, 1983) such that neither figurative nor literal meaning has priority. Familiar figurative expressions may be understood as rapidly as literal ones, especially when contextual information implies the figurative meaning. An addition to the Frisson and Pickering’s (1999) paradigm was the comparison of younger adults and older adults. In the area of language processing, some aspects of language reveal differential aging effects whereas others do not (Wingfield & Stine-Morrow, 2000). The Frisson and Pickering’s paradigm lends itself to the investigations into on-line figurative language processing of older adults as well as off-line measures of comprehension. Although there were no differences in the fixation times for younger and older adults, there were large differences in acceptability, based on probe question answers, of unfamiliar metonymies, indicating differential sensitivity of both groups to figurative language processing. However, total sentence reading times did not differ between the age groups, lending confidence that older adults processed the sentences similarly to younger adults. A complete model of cognitive aging must be able to account for figurative language processing. The on-line measures of fixation time indicate no age-related decrement in the ability to derive or create figurative meaning. Based on their answers to probe questions, older adults were somewhat more likely to reject the metonymies than young adults, suggesting they are more sensitive to figurative language usage. One reason older adults may have rejected the metonymies is that it is difficult to for-
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mulate a yes=no question that captures the intended figurative meaning of the metonymy such that a place is used to refer to a person. The appropriate person is clear for familiar metonymies (e.g., prison implies warden, White House implies President) but less clear for unfamiliar metonymies. Older adults may have chosen to answer the probe questions with a ‘no’ answer because their figurative interpretation did not agree with that used in the probe question (e.g., White House could stand for the President or his staff or the person in charge of press releases). Hence, the older adults may have rejected the metonymy, especially the unfamiliar ones, because they did not interpret the metonymy as referring to the person specified in the probe question, not because they failed to interpret the metonymy figuratively. The results also failed to support general slowing models of cognitive aging. If a general slowing (Myerson, Hale, Wagstaff, Poon, & Smith, 1990; Salthouse, 1985, 1996) holds, first fixation times and total fixation times for older adults should exceed those for younger adults. However, older adults’ total fixation times did not exceed younger adults as would be predicted by a general slowing model. Nor did the sentence reading time differ between younger and older adults. Similarly, if inhibition were weakened by age (Connelly, Hasher, & Zacks, 1991; Hasher & Zacks, 1988; Zacks & Hasher, 1994, 1997), we would again expect age differences in first fixation times or total fixation times. Older adults should fixate longer on familiar metonymies than on the literal controls, reflecting difficulties in suppressing the literal meaning of the metonymy when it is used figuratively. However, there was no difference for older adults’ fixation times between the familiar metonymies and their controls. Thus, both general slowing and inhibitory deficit theories of cognitive aging are not supported by this investigation. The investigation does add to the growing inventory of areas of language that are not affected as people age. Immediate, on-line sentence processing may be age invariant whereas post-interpretive processes may reveal age-group differences (Waters & Caplan, 1999). It may be that those aspects of sentence processing that are required to establish causal and temporal connections between sentences or that are required to integrate sentence information are subject to age-related slowing or inhibitory deficits whereas the immediate allocation of fixation time to individual words and phrases is not.
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