not too ‘shy’ to help catch a thief: recall memory of shy versus non-shy witnesses

www.elsevier.com/locate/paid

Personality and Individual Differences 39 (2005) 1361–1372

Not too �shy� to help catch a thief: Recall memory ofshy versus non-shy witnesses

Joanna D. Pozzulo *, Robert J. Coplan, Julie Wilson

Department of Psychology, Carleton University, 1125 Colonel By Drive, Ottawa, Ont., Canada K1S 5B6

Received 10 January 2005; received in revised form 10 April 2005; accepted 6 June 2005Available online 8 August 2005

Abstract

Witness shyness was examined to determine its impact on recall accuracy in two experiments. It washypothesized that shyness would facilitate witness accuracy, under some conditions. In Experiment 1, wit-nesses were asked to respond to directed recall questions probing crime event and culprit details. Non-shyand shy witnesses produced comparable accuracy rates when describing the culprit. In contrast, non-shywitnesses were more accurate when describing crime environment details than shy witnesses. In Experiment2, arousal was manipulated and a free recall approach was used to assess recall accuracy. Under low arou-sal, shy witnesses were more accurate at describing the culprit than non-shy witnesses, whereas, non-shywitnesses were more accurate at describing crime details than shy witnesses. Under high arousal, differencesin accuracy were not observed across shy and non-shy witnesses.� 2005 Elsevier Ltd. All rights reserved.

Keywords: Shyness; Eyewitness; Testimony; Recall

1. Introduction

An eyewitness to a crime will be relied upon to describe the culprit and provide crime details.Individual differences among eyewitnesses may make some more accurate than others. The goal of

0191-8869/$ - see front matter � 2005 Elsevier Ltd. All rights reserved.doi:10.1016/j.paid.2005.06.010

* Corresponding author.E-mail address: [email protected] (J.D. Pozzulo).

mailto:[email protected]

1362 J.D. Pozzulo et al. / Personality and Individual Differences 39 (2005) 1361–1372

the present research was to explore how individual differences in shyness contribute toward eye-witness recall.

1.1. Personality differences in the eyewitness

There is a paucity of research exploring how individual differences in personality might be re-lated to eyewitness performance. The relative lack of research in this area is likely due to the factthat as an estimator variable (i.e., variables whose effect can only be estimated after the crime,Wells, 1978), personality cannot be manipulated in order to improve eyewitness accuracy. How-ever, as argued by Hosch (1994), any variable theoretically linked to performance in eyewitnesstasks is worth studying.

Personality may influence eyewitness accuracy through its association with memory. For exam-ple, personality related characteristics such as field dependence and locus of control have beendemonstrated to be associated with performance on memory tasks (e.g., Davis & Frank, 1979).However, these same variables have failed to demonstrate consistent associations with overallaccuracy examined in the context of eyewitness paradigms (e.g., Christiaansen, Ochalek, & Swee-ney, 1984).

Ward and Loftus (1985) did not find significant differences in overall eyewitness accuracy be-tween introverts and extraverts, although introverts tended to be more susceptible to acceptpost-event information. Trouve and Libkuman (1992) also reported no significant differences inthe overall accuracy of introverts and extraverts, but were unable to replicate the findings of Wardand Loftus with regards to post-event information. Finally, Bothwell, Brigham, and Pigott (1987)found that participants with high scores in neuroticism performed worse than their non-neuroticcounterparts in an identification task, but only when tested in a high-arousal condition.

1.2. Shyness

Shy persons feel awkward or uneasy in social situations, are self-conscious, and tend to exces-sively monitor their own behaviors (Crozier, 2000). The eyewitness context is a social situation(Wells & Luus, 1990), thus shyness may be a particularly relevant characteristic to examine inthe eyewitness. Moreover, personality traits with biological substrates are most likely to contrib-ute to individual differences in eyewitness performance (Hosch, 1994). In this regard, shyness isalso a good �candidate�, as there is growing evidence to suggest a strong biological basis for shy-ness in children and adults.

Shy individuals differ from their non-shy counterparts on a host of neurological, neuroendocri-nal, and physiological variables. For example, as compared to their peers, extremely shy individualshave higher andmore stable heart rate, greater laryngeal muscle tension, higher norepinephrine andsalivary cortisol levels, larger pupillary dilation, and greater right-frontal EEG activation (seeMar-shall & Stevenson-Hinde, 2001 for a review). These results support the notion that extremely shyindividuals have a lower threshold for psychophysiological arousal (Kagan, 1994).

This lowered threshold for arousal may help to account for shy individuals� tendency to per-ceive potential threat in others and thus become hypersensitive to their environment when in so-cial situations (Van Ameringen, Mancini, & Oakman, 1998). Environmental hypersensitivity maycontribute positively to eyewitness accuracy. Given the threat that strangers represent, shy people

J.D. Pozzulo et al. / Personality and Individual Differences 39 (2005) 1361–1372 1363

may be more likely to devote their undivided attention to studying and evaluating that threat. Assuch, shy individuals may excel in terms of eyewitness memory, particularly in terms of person-related information.

Our review of the literature revealed only one previous study where researchers have exploredthe relation between shyness and eyewitness testimony. In a sample of school-aged children, Roe-bers and Schneider (2001) reported that shy children (as rated by teachers) were less accuratewhen responding to a cued recall task than non-shy children. However, these researchers didnot distinguish between the type of information children were being asked to recall.

The goal of Experiment 1 was to provide a preliminary exploration of the eyewitness accuracyof shy and non-shy individuals. Personality variables may influence eyewitness testimony onlywhen participants with large differences in personality are considered. Drawing upon the extantliterature, it was hypothesized that extremely shy individuals would outperform their non-shycounterparts on tests of eyewitness recall, specifically in terms of person-related information ver-sus environment-related information.

2. Experiment 1

2.1. Method

2.1.1. ParticipantsStudents enrolled in introductory psychology at a university in Eastern Ontario were asked to

complete a pre-test shy measure (N = 841). Students scoring 1 standard deviation (SD = 9.12)above the mean (33.35) were classified as shy and students scoring 1 standard deviation belowthe mean were classified as non-shy. Twenty-one shy students (Mshyness = 48.10, SD = 3.89;range = 44–58) and 21 non-shy students (Mshyness = 18.67, SD = 2.20; range = 13–23) agreed toparticipate. Participants received course credit.

2.2. Materials

2.2.1. Shy questionnaireThe Revised Cheek and Buss Shyness Scale (RCBS; Cheek & Buss, 1981) is a 13-item self-report

measure. Responses are made using a 5-point scale ranging from (1) very uncharacteristic to (5)very characteristic. The RCBS has been used with college students and possesses good psychomet-ric properties (Crozier, 2005).

2.2.2. Filmed crimeA staged theft was filmed in a drug store lasting approximately 60 s. The video commenced with

a female selecting items to purchase. After she placed her shopping basket and purse down to re-trieve an item in an adjacent aisle, a male picked up her purse and quickly left the store.

2.2.3. Open-ended directed question description formParticipants were given a series of eight questions probing details of the culprit. For example,

participants were asked the color of the culprit�s jacket and pants, and whether he had facial hair.


In addition, participants were given a series of eight directed questions probing what they saw inthe crime environment. For example, participants were asked whether there was another person inthe aisle, the price of ‘‘Tums’’, and to name the brand of paper towels on display. The propor-tion of correct responses given for each category (culprit versus crime environment) wascalculated.

2.3. Procedure

Participants were tested individually in the Laboratory. The study was introduced as a projecton societal issues. Participants were asked to watch a videotape while the experimenter preparedthe forms for the study. Following the viewing of the videotaped theft, the participants were in-formed that we were interested in their memory of the crime and culprit. Witnesses then answereddirected questions about the culprit and crime/environment.

2.4. Results

2.4.1. Directed recallThe goal of this analysis was to explore differences in shy and non-shy witnesses in terms of the

proportion of their correctly recalled information related to the culprit and the crime environ-ment. A 2 · 2 mixed design ANOVA was conducted with recall Content (culprit versus crimeenvironment) serving as a within-subjects factor, and Group (shy versus non-shy) serving as a be-tween-subjects factor. The main effect of Group was non-significant, F(1,40) = 1.03, ns. The maineffect of Content was significant (F(1,40) = 108.69, p < .001), however, this main effect was super-ceded by a significant Group · Content interaction, F(1,40) = 4.65, p < .05.

Results from follow-up simple effects analyses indicated that for information regarding the cul-prit, shy and non-shy witnesses did not differ significantly in terms of the proportion of correctitems recalled, t(40) = .29, ns. However, for information regarding the crime environment, shy par-ticipants recalled a significantly lower proportion of correct items than their non-shy counter-parts, t(40) = �2.02, p < .05 (see Table 1).

2.5. Discussion

Our preliminary findings partially supported our hypotheses. Shy and non-shy witnesses didnot differ significantly in their accuracy to questions pertaining to the culprit. However, non-shy witnesses were more accurate than shy witnesses to questions probing the crime environment.

Table 1Mean (SD) proportion of correct items recalled as a function of type of witness and content

Type of witness

Shy Non-shy

Content

Culprit .64 (.20) .62 (.21)Crime environment .22 (.19) .35 (.21)


Given shy individuals are particularly sensitive to and threatened by new persons entering theirenvironment (Van Ameringen et al., 1998), a shy individual�s attention is likely to be focusedon this new person. In an eyewitness context, if a shy witness is focused on the culprit, less atten-tion is available for other crime details in the environment.

It is important to note that it is premature to conclude that there is no difference between shyversus non-shy witnesses. It is possible that the methodology used in this experiment hindered theshy witness� ability to demonstrate superior recall accuracy for the culprit over non-shy witnesses.Participants were exposed to a videotaped rather than a live mock crime. Given the greater threata live situation poses than videotaped, it might well be the case that effects would have been largerwith the use of a live mock crime. Moreover, given that we used a directed questioning method,witnesses were restricted to describe the details we asked about. Witnesses may have been able torecall more information than the questions probed. Using a free narrative approach would be abetter test for examining differences.

2.5.1. The role of arousalShy individuals become particularly anxious when in a social situation (Van Ameringen et al.,

1998). Persons who are more anxious tend to perform worse on tests of eyewitness accuracy andface recognition (Mueller, Bailis, & Goldstein, 1979; Powers, Andriks, & Loftus, 1979).

The Yerkes–Dodson rule (Yerkes & Dodson, 1908) suggests that a moderate level of arousalfacilitates performance (e.g., recall) compared to low or high arousal. Shy individuals may beat their �optimal� level of arousal for eyewitness accuracy when performing at baseline. Externallyinduced stress or anxiety may put the shy witness beyond their optimal performance level. Con-versely, this additional stress or anxiety may aid non-shy witnesses placing them in their optimalrange.

Critics of the Yerkes–Dodson rule have argued that there are various arousal systems and nounitary conception of arousal (e.g., Neiss, 1988). Moreover, results from studies attempting to val-idate the rule have been diverse (see Christianson, 1992). Acknowledging these difficulties, we usethe Yerkes–Dodson rule as a general framework to begin to understand the relation between shy-ness, arousal, and memory rather than to use it for a causal interpretation of our data.

The goal in the second experiment was to determine the robustness of our results using free re-call tasks to gather descriptions of the culprit and crime (typically what initially police would askfrom witnesses). In addition, an arousal manipulation (high versus low) was included to furtherexplore our speculations regarding the moderating effect of arousal on the eyewitness recall ofshy and non-shy individuals.

3. Experiment 2

3.1. Method

3.1.1. ParticipantsStudents enrolled in introductory psychology at a university in Eastern Ontario were asked to

complete a pre-test shy measure (N = 1006). As previous, students scoring 1 standard deviation(SD = 9.12) above the mean (32.86) were classified as shy and students scoring 1 standard


deviation below the mean were classified as non-shy. Twenty-one shy students (Mshyness = 46.43,SD = 3.39; range = 42–60) and 21 non-shy students (Mshyness = 19.29, SD = 3.39; range = 13–24)agreed to participate. Participants received course credit.

3.2. Materials

3.2.1. Shy questionnaireThe RCBS as described in Experiment 1 was used to select our sample.

3.2.2. Stress and arousal questionnaireThe Stress-Arousal Checklist (SACL; Mackay, Cox, Burrows, & Lazzerini, 1978) is a 30-item

self-report measure consisting of adjectives commonly used to describe one�s psychological expe-rience of �stress�. Two dimensions are examined; stress (18 items, a = .90) is a subjective generalsense of well-being that consists of feelings ranging from pleasant to unpleasant to the externalenvironment and arousal (12 items, a = .80) consists of feelings ranging from wakefulness todrowsiness, or vigorousness and is viewed as ongoing somatic or autonomic activity.

3.2.3. Filmed crimeA staged theft was filmed in a university dormitory lasting approximately 60 s. A male entered

an unlocked dormitory rummaging through the tenant�s items. A woman entered while he wassearching her purse. He quickly ran out with the purse.

3.2.4. Free recall description formParticipants were requested to write down all they could remember about the crime and then

the culprit�s appearance.

3.2.5. Post-experimental anxietyParticipants rated their overall level of anxiety using a scale ranging from (1) not at all to (5)

very anxious.

3.2.6. Arousal manipulationTo induce arousal, a video recorder was placed in front of the participants. They were informed

that we would be videotaping them as they watched the video and that we would later be scoringtheir facial expressions and body movements. In addition, a full-length mirror was facing themfrom across the room. In the low arousal condition (control), the props were removed. The arou-sal manipulation was a between-subjects manipulation.

3.3. Procedure

The procedure described in Experiment 1 was used. Half of the shy and half of the non-shy par-ticipants were randomly assigned to the high arousal condition, whereas the remaining partici-pants were assigned to the low arousal condition. Following the viewing of the videotapedtheft, witnesses rated their level of stress. Then, they described the crime and culprit. Lastly, wit-nesses rated their anxiety.


3.4. Results

3.4.1. Scoring of free recall descriptionsTwo independent raters devised a coding scheme delineating the actions occurring during the

crime. Schemes were compared to produce a master key from which all recall descriptions ofthe crime would be scored. Each participant received a score for the total number of crimedescriptors recalled and a score for the proportion of correct crime descriptors recalled.

A coding scheme also was devised for the free recall description of the culprit based on hisappearance. Each descriptor of the culprit provided by the participant received 1 point. Age,height, and weight were given an acceptable range (age ± 3 years; height ± 2 inches; weight ± 10pounds). Each participant received a score for the total number of culprit descriptors recalled anda score for the proportion of correct culprit descriptors recalled.

3.4.2. Rater reliabilityAfter 10 descriptions were scored (for each the crime and culprit), an independent rater ran-

domly selected and scored 5 descriptions of the crime and 5 descriptions of the culprit. Discrep-ancies between raters were discussed and a decision was reached on how to code the item. Thisprocess continued until reliability coefficients reached .8.

3.4.3. StressThe goal of the first analysis was to explore differences in self-reported emotional experiences

during testing as a function of shyness group and arousal condition. A multivariate factorial anal-ysis of variance was conducted with Group (shy versus non-shy) and Condition (low arousal ver-sus high arousal) as independent variables, and self-reported arousal, stress, and post-test anxietyserving as dependent variables. Results indicated a significant multivariate effect of Group,F(3,80) = 5.08, p < .01, and a significant Group · Condition interaction, F(3,80) = 3.95, p < .05.

Examination of subsequent univariate analyses for stress indicated a significant effect of Group(F(1,82) = 7.13, p < .001) and a significant Group · Condition interaction (F(1,82) = 10.36,p < .001). Results for post-test anxiety indicated significant effects of Group (F(1,82) = 9.13,p < .001) and Condition (F(1,82) = 4.10, p < .05), and the Group · Condition interaction ap-proached significance (F(1,82) = 3.37, p < .07). Non-significant results were found for arousal.None were expected given arousal on the measure used referred to somatic or autonomic activity.

In the low arousal condition, shy and non-shy witnesses did not differ in terms of their self-re-ported stress, t(38) = �.42, ns, or post-test anxiety, t(38) = �.97, ns. However, in the high arousalcondition, shy witnesses reported significantly more stress, t(44) = 3.95, p < .001, and post-test-anxiety, t(44) = 3.16, p < .01, than their non-shy counterparts (see Table 2).

3.4.4. Free recallThe goal of the next set of analyses was to explore differences in free recall of information re-

lated to the culprit and the crime environment as a function of shyness group and arousal condi-tion. The first analysis involved the total number of details recalled from the video. A 2 · 2 · 2mixed design ANOVA was conducted with Total-Content (culprit versus crime environment)serving as a within-subjects factor, and Group (shy versus non-shy) and Condition (low arousalversus high arousal) serving as between-subjects factors. Results indicated a significant main effect

Table 2Mean (SD) ratings of stress as a function of type of witness and arousal condition

Type of witness

Shy Non-shy

Low-arousal condition

Stress ratingStress 8.05 (2.69) 8.35 (1.63)Arousal 4.70 (2.52) 6.10 (1.89)Anxiety 2.25 (.97) 1.95 (.99)

High-arousal condition

Stress ratingStress 9.48a (2.81) 6.26b (2.72)Arousal 5.09 (2.73) 5.13 (1.71)Anxiety 3.32a (1.20) 2.00b (1.38)

Note. Means not sharing a common subscript differ significantly at the .05 level.


of Total-Content (F(1,82) = 8.76, p < .01), with witnesses more likely to recall details about thecrime environment (M = 9.92, SD = 3.05) than the culprit (M = 8.73, SD = 2.60).

The final analysis involved the proportion of correct details recalled from the video. A second2 · 2 · 2 mixed design ANOVA was conducted with Correct-Content (culprit, crime environ-ment) serving as a within-subjects factor, and Group (shy, non-shy) and Condition (low arousal,high arousal) serving as between-subjects factors. Significant main effects were observed for Con-dition, F(1,82) = 6.27, p < .05, and Correct-Content, F(1,82) = 25.87, p < .001. These main effectswere superceded by significant two-way interactions for Group · Correct-Content,F(1,87) = 4.37, p < .05, and Condition · Correct-Content, F(1,82) = 4.60, p < .05. However,these two-way interactions were further superceded by a significant three-way interaction forGroup · Correct-Content · Condition, F(1,82) = 4.48, p < .05.

Results from simple effects analyses indicated that under the high arousal condition, only a sig-nificant effect of Correct-Content was evident (F(1,44 = 4.03, p < .05), with witnesses more likelyto recall a higher proportion of correct details about the crime environment (M = .82, SD = .18)than the culprit (M = .75, SD = .13).

Under the low arousal condition, results also indicated a significant main effect of Correct-Con-tent, F(1,38) = 30.09, p < .001. However, this main effect was superceded by a significantGroup · Correct-Content interaction, F(1,38) = 10.19, p < .01. Results from further follow-upsimple effects analyses indicated that for information regarding the culprit, shy witnesses recalleda significantly higher proportion of correct items than their non-shy counterparts (t(38) = 2.22,p < .05). However, with regards to information pertaining to the crime environment, shy witnessesrecalled a significantly lower proportion of correct items than their non-shy counterparts,t(38) = �2.23, p < .05 (see Table 3).

3.5. Discussion

Consistent with the notion that shy individuals are more likely to focus on a person than non-shy individuals, under low arousal, shy witnesses were more accurate recalling culprit details than

Table 3Mean (SD) proportion of correct items recalled as a function of type of witness, arousal condition, and content

Type of witness

Shy Non-shy

Low-arousal condition

ContentCulprit .82a (.11) .69b (.24)Crime environment .89a (.10) .95b (.08)

High-arousal condition

ContentCulprit .74 (.12) .75 (.15)Crime environment .81 (.21) .82 (.95)

Note. Means not sharing a common subscript differ significantly at the .05 level.


non-shy witnesses. In contrast, when recalling the crime, non-shy witnesses were more accuratethan shy witnesses. Novel persons are considered a potential threat to those who are shy andin turn, these novel persons will garner the shy individual�s attention more so than a non-shy indi-vidual (Crozier, 2001). In an eyewitness context, the shy witness makes a more accurate witnessthan the non-shy witness when describing the culprit. However, this superiority may be reducedor eliminated when external arousal is increased.

The Yerkes–Dodson rule (Yerkes & Dodson, 1908) suggests that a moderate level of arousal isoptimal for performance compared to low or high levels of arousal. The shy individual alreadymay be at this optimal level of arousal compared to non-shy individuals. Additional environmen-tal arousal may worsen a shy witness� performance. On the other hand, this same environmentalarousal may serve to enhance a non-shy witness� performance.

Under high arousal, shy witnesses lost their �advantage� over non-shy witnesses describing theculprit to the same degree of accuracy. When describing the culprit, shy witnesses did worse underhigh arousal compared to low arousal and non-shy witnesses did better under high arousal com-pared to low arousal. Also, differences in accurately describing the crime were eliminated.

4. General discussion

Two experiments were conducted to examine the impact of witness shyness on recall. It washypothesized that under some conditions, shy witnesses would prove to be more accurate, partic-ularly in terms of their abilities to describe people. Shy versus non-shy participants watched astaged crime. In Experiment 1, witnesses were asked to respond to directed recall questions prob-ing crime and culprit details. In Experiment 2, arousal was manipulated during the witnessing ofthe crime. Witnesses were asked to use a free narrative to recall crime and culprit details.

To our knowledge, this research was the first to directly examine the relation between shynessand eyewitness accuracy in adults. Results provided some support for our hypotheses. In Exper-iment 1, shy witnesses were found to recall the culprit slightly more accurately than non-shy wit-nesses. However, shy witnesses may not have demonstrated their superiority in recall over non-shywitnesses due to the methodology employed (e.g., videotaped mock crime rather than live mock


crime, directed recall rather than free recall). Shy witnesses were significantly less accurate in theirrecall of the crime environment, suggesting that their focus on person-related information mayhave detracted from their attention to other details. According to Easterbrook�s (1959) cue-utili-zation hypothesis, as arousal increases, restriction on the range of cues attended to by the observerdecreases.

In Experiment 2, we used an open-ended approach to assessing recall. Also, we examined thepossible interaction between shyness and arousal. As predicted, results indicated that arousal maybe an important moderator variable in the relation between shyness and eyewitness accuracy. Shywitnesses recalled culprit details more accurately than non-shy witnesses under low arousal. Incontrast, non-shy witnesses recalled crime details more accurately than shy witnesses under higharousal.

In an eyewitness context, the culprit may garner much of a shy witness� attention. The culpritmay produce a phenomenon similar to �weapon focus�, where a weapon in a crime becomes thefocus of the witness� attention (Steblay, 1997). The witness has difficulty recalling crime and cul-prit details, however, the weapon is described with accuracy. In support of this notion, shy wit-nesses were found to have lower accuracy when describing environment details compared tonon-shy witnesses in both Experiments 1 and 2 (low arousal condition).

The Yerkes–Dodson rule (1908) suggests that a moderate level of arousal is optimal (comparedto low or high levels) to facilitate performance (e.g., recall). Although criticisms against the Yer-kes–Dodson rule have been stated (e.g., Christianson, 1992), as a general framework, the rule mayhave some utility. Moreover, Eysenck (1982) postulates that with increased arousal, attentionalmechanisms are overloaded and memory for internal and external details is decreased. Extremeshyness is characterized by a constellation of physiological substrates that are indicative of a lowerthreshold for arousal (e.g., Kagan, 1994). As such, shy individuals may be more aroused under�baseline conditions�. Thus, it is predicted that as long as the crime is not personally threatening,shy individuals are at an optimal level of arousal for witnessing and later accurately recalling theculprit. When arousal is increased, shy witnesses are disadvantaged for describing the culprit be-cause they are over their optimal arousal level, whereas, non-shy witnesses should improve be-cause they are now in their optimal arousal range. Also, shy witnesses should have additionaldifficulty at describing event details under high arousal. Consistent with our predictions, shy wit-nesses were no longer more accurate at describing the culprit than non-shy witnesses. Non-shywitnesses were more, although not significantly, accurate at describing crime details than shywitnesses.

5. Conclusions

These two experiments suggest that shy and non-shy witnesses perform differentially on recalltasks. The relation is further complicated when considering content of the crime and degree ofarousal present during the witnessing of the crime. This research demonstrates how estimator vari-ables can interact to produce different results in comparison to single estimator variables. The impor-tance of examining combinations of estimator variables to reach more accurate conclusions isevident. Moreover, estimator variables should be examined with recall and recognition as depen-dent variables, as they may produce different patterns of results. Also, it is important to consider


inaccuracy and its relation to shyness. For example, are shy witnesses more likely to makecommission errors than non-shy witnesses. Furthermore, to reach more ecologically valid conclu-sions, shy and non-shy witnesses should be tested using a live mock crime design. Clearly, morework on the effects of shyness is necessary to unravel shyness effects in an eyewitness context.

Acknowledgements

This research was supported by a grant from the Social Sciences and Humanities ResearchCouncil to the first author. The authors wish to thank Kim O�Neil for her help in the collectionof data.

References

Bothwell, R. K., Brigham, J. C., & Pigott, M. A. (1987). An exploratory study of personality differences in eyewitnessmemory. Journal of Social Behavior and Personality, 2(3), 335–343.

Cheek, J. M., & Buss, A. H. (1981). Shyness and sociability. Journal of Personality and Social Psychology, 41, 330–339.Christianson, S.-A. (1992). Emotional stress and eyewitness memory: A critical review. Psychological Bulletin, 112,

284–309.Christiaansen, R. E., Ochalek, K., & Sweeney, J. D. (1984). Individual differences in eyewitness memory and confidence

judgments. Journal of General Psychology, 110(1), 47–52.Crozier, W. R. (2000). Blushing, social anxiety, and exposure. In W. R. Crozier (Ed.), Shyness: Development,

consolidation, and change (pp. 154–170). London: Routledge.Crozier, W. R. (2001). Understanding Shyness. London: Palsgrave.Crozier, W. R. (2005). Measuring shyness: Analysis of the Revised Cheek and Buss Shyness scale. Personality and

Individual Differences, 38, 1947–1956.Davis, J. K., & Frank, B. M. (1979). Learning and memory of field independent–dependent individuals. Journal of

Research in Personality, 13(4), 469–479.Easterbrook, J. A. (1959). The effect of emotion on cue utilization and the organization of behaviour. Psychological

Review, 66, 183–201.Eysenck, M. W. (1982). Attention and arousal: Cognition and performance. Berlin, Germany: Springer-Verlag.Hosch, H. (1994). Individual differences in personality and eyewitness identification. In D. F. Ross, J. D. Read, & M. P.

Toglia (Eds.), Adult eyewitness testimony: Current trends and developments (pp. 328–347). Cambridge: CambridgeUniversity Press.

Kagan, J. (1994). On the nature of emotion monographs for the society for research in child development. CambridgeUniversity Press.

Mackay, C., Cox, T., Burrows, G., & Lazzerini, T. (1978). An inventory for the measurement of self-reported stress andarousal. British Journal of Social and Clinical Psychology, 17(2), 283–284.

Marshall, P. J., & Stevenson-Hinde, J. (2001). Behavioral inhibition: Physiological correlates. In R. Crozier & L. E.Alden (Eds.), International handbook of social anxiety (pp. 53–76). Chicester: John Wiley.

Mueller, J. H., Bailis, K. L., & Goldstein, A. G. (1979). Depth of processing and anxiety in facial recognition. BritishJournal of Psychology, 70, 511–515.

Neiss, R. (1988). Reconceptualizing arousal: Psychological states in motor performance. Psychological Bulletin, 103,345–366.

Powers, P. A., Andriks, J. L., & Loftus, E. F. (1979). The eyewitness accounts of females and males. Journal of AppliedPsychology, 64, 339–347.

Roebers, C. M., & Schneider, W. (2001). Individual differences in children�s eyewitness recall: The influence ofintelligence and shyness. Applied Developmental Science, 5(1), 9–20.


Steblay, N. M. (1997). Social influence in eyewitness recall: A meta-analytic review of lineup instruction effects. Law and

Human Behavior, 21, 283–298.Trouve, R. J., & Libkuman, T. M. (1992). Eyewitness performance of personality types as a function of induced

arousal. American Journal of Psychology, 105(3), 417–433.Van Ameringen, M., Mancini, C., & Oakman, J. (1998). The relationship of behavioral inhibition and shyness to

anxiety disorder. The Journal of Nervous and Mental Disease, 186(7), 425–431.Ward, R. A., & Loftus, E. F. (1985). Eyewitness performance in different psychological types. The Journal of General

Psychology, 112(2), 191–200.Wells, G. L. (1978). Applied eyewitness-testimony research: System variables and estimator variables. Journal of

Personality and Social Psychology, 12, 1546–1557.Wells, G. L., & Luus, C. A. E. (1990). Police lineups as experiments: Social methodology as a framework for properly-

conducted lineups. Personality and Social Psychology Bulletin, 16, 106–117.Yerkes, R. M., & Dodson, J. D. (1908). The relation of strength of stimulus to rapidity of habit-formation. Journal of

Comparative Neurology and Psychology, 18, 459–482.

not too ‘shy’ to help catch a thief: recall memory of shy versus non-shy witnesses

Documents