PERSONALITY AND DRUGS IN VISUAL FIGURAL AFTEREFFECTS

The effects of dexedrine and phenobarbitone on visual figural aftereffect (VFAE) were examined in 32 postgraduate students selected after a preliminary testing with the Maudsley Personality Inventory. Calcium tablets were used as placebos. The subjects were repeatedly tested under each of the treatment conditions. The results supported the following conclusions: (1) extraverted subjects relative to introverted ones had larger VFAE; (2) the size of VFAE increased under the influence of phenobarbitone in all personality groups except N+E+ and N-E-; (3) interactions between the drug treatments and personality variables in effects on VFAE did not occur.     

The distance gradient in the after-effect of kinaesthetic width judgement

The combined effects of inspection-time and interfigural distance on a kinaesthetic figural after-effect were determined. The figural after-effect was defined as the degree to which a 2-in. width appeared to shrink following prolonged inspection of larger widths. The inspection-widths were 2.0, 2.5, 3.0, 3.5, 4.0, and 4.5 in. and the inspection-times were 10 and 50 sec. A control group which did not inspect any widths was also employed. 156 subjects were tested. The results indicated that the classical non-monotonic relationship between interfigural distance and figural after-effect was not present. Instead, the figural after-effect increased as a negatively accelerated function of interfigural distance. Increasing inspection-time increased the asymptotic level of the figural after-effect. These results were interpreted in terms of the effects of anchors on judgements of magnitude.     

Extraversion and neuroticism: Investigation of resting electrodermal activity

In 1967 Eysenck published his biological account of extraversion and neuroticism. In the same year Claridge identified several problems with this theory. More recently Robinson has detailed a promising modification to Eysenck's theory which addresses many of the issues raised by Claridge. Drawing on Robinson's theory it was hypothesised that differences in resting electrodermal activity (EDA) would contrast extraverted‐neurotics (low arousal) and introverted‐neurotics (high arousal). The Eysenck Personality Questionnaire (EPQ) was used to identify four extreme groups of female participants: extraverted‐stable (n = 16), extraverted‐neurotic (n = 15), introverted‐stable (n = 8) and introverted‐neurotic (n = 16). EDA measures of skin conductance level (SCL) and non‐specific skin conductance response (NS‐SCR) were collected during two rest periods. Planned contrasts between the extraverted‐neurotic and introverted‐neurotic groups provided support for Robinson's theory on SCL but not NS‐SCR. It was argued that the results for NS‐SCR frequency could be accommodated by Robinson's theory if NS‐SCR was conceptualised as a measure of cortical reactivity to unspecified stimuli rather than as a measure of tonic arousal.     

The effect of a low rate of regular signals upon the reaction times of introverts and extraverts

In an RT (reaction time) task involving responding to infrequent, regular signals, extraverts produced higher proportions of missed signals and lengthened RT's than introverts did. This result was only obtained after some time on task and is evidence that inhibitory states are formed more rapidly in extraverted subjects under low stimulation conditions. In a more extended version of the task, mean RT was found to be longer in extraverted than introverted subjects in the second half of the experiment though there was no significant difference between the groups in the first half. These findings are complementary to data from previous studies showing that extraverts generate stronger inhibitory potential in continuous responding tasks, or that their characteristic arousal level may be lower than that of introverted subjects. The need to distinguish between the different explanatory constructs is discussed and a simple model amalgamating the major theoretical positions is outlined.     

Would introverts be better off if they acted more like extraverts? Exploring emotional and cognitive consequences of counterdispositional behavior

People enjoy acting extraverted, and this seems to apply equally across the dispositional introversion-extraversion dimension (Fleeson, Malanos, & Achille, 2002). It follows that dispositional introverts might improve their happiness by acting more extraverted, yet little research has examined potential costs of this strategy. In two studies, we assessed dispositions, randomly assigned participants to act introverted or extraverted, and examined costs-both emotional (concurrent negative affect) and cognitive (Stroop performance). Results replicated and extended past findings suggesting that acting extraverted produces hedonic benefits regardless of disposition. Positive affect increased and negative affect did not, even for participants acting out of character. In contrast, we found evidence that acting counterdispositionally could produce poor Stroop performance, but this effect was limited to dispositional extraverts who were assigned to act introverted. We suggest that the positive affect produced by introverts' extraverted behavior may buffer the potentially depleting effects of counterdispositional behavior, and we consider alternative explanations. We conclude that dispositional introverts may indeed benefit from acting extraverted more often and caution that dispositional extraverts may want to adopt introverted behavior strategically, as it could induce cognitive costs or self-regulatory depletion more generally.     

Exploring personality preferences in relation to psychological career resources among managerial staff in the Western Cape fast food industry

The study explored the relationship between individuals' personality preferences (as measured by the Myers-Briggs Type Indicator, Form M) and their psychological career resources (as measured by the Psychological Career Resources Inventory) and whether the personality types differed significantly in terms of their psychological career resources. The participants were a non-probability sample (N?=?81; females?=?74%, blacks?=?78%) of managerial-level staff from five fast food franchise restaurants in the Western Cape, South Africa. Quantitative statistical procedures were used to explore the association between the participants' personality preferences and psychological career resources. Findings suggest introverted and extraverted personality type preferences to be significantly associated with the participants' psychological career resources. Major differences were observed for the introverted sensing feeling perceiving (ISFP), extraverted sensing feeling judging (ESFJ), introverted sensing feeling judging (ISFJ), extraverted sensing thinking judging (ESTJ) and introverted sensing thinking judging (ISTJ) personality types in their relationship to the career preference of variety/creativity, need for career growth/development, their self/other skills and social connectivity.     

Channeling identity: A study of storytelling in conversations between introverted and extraverted friends

This narrative study examined the process of personal storytelling between college-age friends who were similarly introverted or extraverted. Participants were 19 introverted and 20 extraverted same-sex pairs (49% female) who had been friends for an average of 18 months. Stories emerged spontaneously during 10-min catch-up conversations. Extraverted friends more often told stories that changed the topic, and more often co-constructed story plots. Introverted friends more often told stories that were embedded in a developing theme, and constructed story plots solo. With regard to content, extraverted friends told stories about romance more so than introverted friends, whose stories more often concerned family/hometown, and older events. The findings suggest that the traits of extraversion and introversion channel the identity-making process.     

High Self-Deceivers Internalize Self-Presentation of Extraversion Through Biased Evaluation of Their Performance1

This study examined whether high self-deceivers form their overly positive perception of their traits through overestimating their performance of self-presentation where they need to impress others as being extraverted/introverted, exhibiting more internalization of self-presentation (IOSP) of the trait. Participants were instructed to give either an extraverted or introverted impression through an oral (Study 1, N = 39) or written (Study 2, N = 62) self-presentation. Participants reported dispositional self-deception, self-presentation efficacy, and extraversion before and after self-presentation. Independent raters provided other-reported extraversion by examining the self-presentation. Across the two studies, two-way mixed ANOVA revealed that predicted change in extraversion occurred only for participants who made extraverted self-presentation. With the change in extraversion as an index of IOSP, mediation analyses revealed indirect effects of dispositional self-deception on IOSP via self-presentation efficacy but not other-reported extraversion. These results suggested that (a) people only internalize socially desirable traits like extraversion but not introversion, (b) writing to others is sufficient to cause IOSP, and (c) high self-deceivers internalize extraverted self-presentation not through actual performance but its subjective evaluation.     

Extraversion, introversion, and visual interaction.

20 extraverts and 20 introverts were selected from a population of college students on the basis of their responses to the Maudsley Personality Inventory. These 40 young women were interviewed by one confederate of each sex. Six trained judges recorded visual and speech behavior by viewing through a one-way mirror and watching videotaped records. Analysis showed that extraverted women engaged in longer gazing than the introverted ones. The extraverted women gazed longer during listening than did introverted women. The proportion of time spent in gazing while speaking was not associated with extraversion. Also, women spent a greater proportion of time looking at a female interviewer than at a male interviewer.     

The relationships between morningness-eveningness, ageing and personality

In an attempt to study the relationship between ageing and personality and the morningness-eveningness dimension two experiments were carried out. In experiment I, an Italian version of the Morningness-Eveningness Questionnaire (MEQ) was administered to 435 Ss ranging in age from 20 to 79 yr, and divided in to six age groups. In comparison with younger people older S tended to display greater Morningness-Eveningness scores. These results suggest that ageing relates to a shifting toward morningness. In Experiment II the Eysenck Personality Questionnaire (EPQ) and the MEQ were administered to 233 Ss (20–29 yr). Morning-types had significantly higher N scores and tended to be insignificantly more introverted. Evening-types had significantly higher N scores and tended to be insignificantly more extraverted. The present findings are consistent with reports of a tendency for morning-types to be introverted and for evening-types extraverted. However, they do provide some evidence of individual differences on the neuroticism and psychoticism dimensions of personality between the two diurnal types.     

情绪对不同外倾水平个体行为抑制的影响

采用双选择oddball实验范式与事件相关电位（ERP）技术,探讨了情绪对行为抑制的影响以及外倾性的调节作用。行为数据发现,相比标准刺激,被试对偏差刺激的反应时显著更慢,证明实验成功诱发了行为抑制效应。在内倾组,负性刺激下偏差与标准刺激反应时差值显著长于正性刺激条件,而在外倾组无显著差异。脑电数据发现,在N2成分上,内倾组在正性情绪下的波幅显著小于负性和中性情绪,而在外倾组,不同情绪下的波幅不存在显著差异。在P3成分上,内倾组在正性情绪下的波幅显著大于负性和中性情绪,相反,外倾组在负性情绪下的波幅显著大于正性和中性情绪。结果表明,情绪对行为抑制的影响受到了个体外倾性水平的调节。     

The effect of state extraversion on four types of affect

The primary purpose of this study was to determine the effect of state extraversion on different types of affect. Ninety six participants were instructed to be extraverted or introverted in a 10‐minute dyadic discussion. State extraversion had a strong effect on positive affect and smaller (but still strong) effects on pleasant and activated affect, with these latter two effects almost equal in magnitude. This pattern of findings appears to increase confidence that the effect of state extraversion is genuine rather than the result of construct overlap, in that extraversion's effect on positive affect is not dominated by its effect on activated affect. No support for reward sensitivity as a potential explanatory mechanism was found. Copyright © 2009 John Wiley & Sons, Ltd.     

Collaborative narration of the past and extraversion

We propose that collaborative narration is a process in which narrative identity develops, and we examine individual differences in extraversion in such narration. Two studies are presented: retrospective and experience sampling episodes of collaborative narration, the first with self-defining memories, the second with everyday narration. Across both studies, extraversion was associated with an increased frequency in collaborative narration. This finding was not explained by the ‘talkativeness’ item in the extraversion measures. Further, more extraverted people shared their self-defining memories with more people and were more comfortable sharing than less extraverted people, the impact of extraversion was specific to mutual reminiscence in everyday narration, and mutual reminiscence was more enjoyable for those who are more extraverted than introverted. Implications from these data for understanding individual differences in identity and narrative development are discussed.     

Individual differences in speed of retrieval from semantic memory

In the first of two experiments, the stimulus items consisted of category names followed by a single letter (e.g., fruit-P). The subjects (half introverted, half extraverted) were required to respond as quickly as possible with a member of the specified category starting with the letter. Extraverts responded significantly faster than introverts, and more so when the most likely response was of low frequency than when it was of high frequency. In the second experiment, subjects were assigned to one of four groups representing the four combinations of high and low Extraversion and high and low General Activation. The speed-of-recall task from the first experiment was used on some trials; on the remaining trials, a speed-of-recognition task was used. Extraverts had greater response speed than introverts for recall, but not for recognition. That finding, plus interactions between Extraversion and General Activation, suggested an interpretation of the results in terms of the Yerkes-Dodson Law.     

National Differences in Subjective Well-Being: The Interactive Effects of Extraversion and Neuroticism

Extraversion and neuroticism interact to affect subjective well-being (SWB) at the individual level of analysis, so that introverted neurotics tend to be particularly miserable. The goal of this study is to determine if this interaction can also be detected at a national level. Findings based on data from 30 countries confirmed that the interaction between extraversion and neuroticism was an extremely strong predictor of satisfaction with life and affect, and a similar though not significant effect was observed with happiness. Neuroticism lowered satisfaction with life and affect among all nations, but more so among introverted nations than among extraverted ones. These findings further confirm that personality traits can be used to extend our understanding of national differences regarding SWB. They also further validate national SWB scores, as they relate to personality in a complex but theoretically meaningful manner.     

The influence of cognitive load on self-presentation: can cognitive busyness help as well as harm social performance?

Extra cognitive loads can hinder challenging self-presentations by usurping needed cognitive resources but also may sometimes improve them by shifting attention away from negative self-preoccupation. In Study 1, extraverts and introverts participated in an interview in which they presented themselves as either extraverted or introverted. Congruent self-presentations, which should be cognitively nondemanding, were unaffected by a cognitive busyness manipulation (rehearsing an 8-digit number). However, incongruent self-presentations were affected by busyness. Busyness decreased the effectiveness of extraverts who tried to appear introverted but increased the effectiveness of introverts who tried to appear extraverted. Study 2 found that introverts, who also tend to be socially anxious, reported less public self-consciousness and fewer negative self-focused thoughts when they were busy than when they were not busy.     

Repeated post- or presession cocaine administration: roles of dose and fixed-ratio schedule

Effects of repeated administration of cocaine to animals behaving under operant contingencies have depended on when the drug is given. Moderate doses given presession have generally led to a decrease in the drug's effect, an outcome usually referred to as tolerance. When these same doses have been given after sessions, the usual result has been no change or an increase in the drug's effects, with the latter usually referred to as sensitization. In the present study, repeated postsession administration of a relatively small dose of cocaine (3.0 or 5.6 mg/kg) to pigeons responding under a multiple fixed-ratio 5, fixed-ratio 100 schedule of food presentation generally resulted in tolerance to the rate-decreasing effects of the drug. When the same dose was given before sessions, little additional tolerance was observed, although some subjects showed further tolerance in the small-ratio component. A regimen of repeated postsession injection of larger (10.0-23.0 mg/kg) doses suppressed key pecking during the session; responding resumed following discontinuation of postsession administrations. Effects of postsession administration of cocaine, therefore, depended on the dose, with smaller doses leading to tolerance and larger ones to suppression of behavior during the session. Effects of postsession drug administration of either small or large doses were not related to whether effects of postsession drug were experienced mainly in the operant test chamber or in the pigeon's home cage. The results with large postsession doses are compatible with a view that the drug acted as a Pavlovian unconditional stimulus, with the session-related stimuli acting as a long-duration Pavlovian conditional stimulus. Tolerance following postsession administration of the smaller doses challenges the view that it depended on experiencing the drug's effects while the arranged reinforcement contingencies were in effect.     

Metric properties of spatial images generated from locomotion: The effect of absolute size on mental scanning

The mental scanning paradigm has demonstrated that the time taken to scan the mental visual image of a map is linearly related to the scanned distances. The experiments reported here aimed at exploring the influence of two factors on mental scanning: (1) the modality through which the environment is explored, that is visual locomotion; and (2) the size of the environment. Three groups of participants had to study three paths of different sizes: large, intermediate and small. After walking on the paths, participants had to mentally scan them. In Experiment 1 an effect of the absolute size was found, which was due to the participants who took longer and relied on a kinaesthetic strategy to study the path. Experiment 2 was a repetition of the first but the duration of the learning time was controlled. A significant difference between size conditions due to longer scanning times for the larger configuration was found. Experiment 3 compared two learning strategies: visual and kinaesthetic. Also in this case a significant size effect due to longer latencies for scanning over the larger configuration was found. In all experiments a significant effect of distance and the typical time–distance coefficients of mental scanning were also found. Results suggest that the learning time duration and the spatial kinaesthetic strategy are both important for encoding the actual size of the environment.     

The causal effects of extraversion on positive affect and neuroticism on negative affect: Manipulating state extraversion and state neuroticism in an experimental approach

Although the relationships between extraversion and positive affect and between neuroticism and negative affect are powerful, the patterns of causality accounting for them are unknown. We employed an experimental methodology to manipulate state extraversion and state neuroticism to determine their causal status. In Experiment 1, state extraversion was manipulated by instructing participants to act extraverted and introverted during two different discussions with two other participants. Participants reported more positive affect when instructed to act extraverted than when instructed to act introverted, and this finding was supported by the ratings of observers. In Experiment 2, state neuroticism was manipulated by instructing participants to act neurotic and emotionally stable during two different discussions. Participants reported more negative affect when instructed to act neurotic than when instructed to act stable. Thus, at least some part of the extraversion-positive affect and neuroticism-negative affect relationships may be accounted for by the causal influences of extraverted behavior and neurotic behavior, respectively.