Neurocognitive variability in high-functioning individuals: implications for the practice of clinical neuropsychology

Knowledge of neurocognitive performance patterns of normal, healthy individuals is necessary, as clinicians may not always take into account normal intra-individual variability, demonstrated here in a sample of 20 healthy individuals with particularly high educational achievement (i.e., holding doctorate degrees). The data indicate that neurocognitive abilities are not equally distributed within a given individual. Some participants in the sample achieved some test scores at the intellectually disabled to borderline range but also some scores in the high average to superior range. The practice of deductive reasoning in clinical neuropsychology may be prone to false positive conclusions about neurocognitive functioning where base rates of neurocognitive impairments are low and pre-existing educational achievements are high.     

Benefits of all work and no play: the relationship between neuroticism and performance as a function of resource allocation

The authors evaluate a model suggesting that the performance of highly neurotic individuals, relative to their stable counterparts, is more strongly influenced by factors relating to the allocation of attentional resources. First, an air traffic control simulation was used to examine the interaction between effort intensity and scores on the Anxiety subscale of Eysenck Personality Profiler Neuroticism in the prediction of task performance. Overall effort intensity enhanced performance for highly anxious individuals more so than for individuals with low anxiety. Second, a longitudinal field study was used to examine the interaction between office busyness and Eysenck Personality Inventory Neuroticism in the prediction of telesales performance. Changes in office busyness were associated with greater performance improvements for highly neurotic individuals compared with less neurotic individuals. These studies suggest that highly neurotic individuals outperform their stable counterparts in a busy work environment or if they are expending a high level of effort.     

Analysis of WAIS-IV index score scatter using significant deviation from the mean index score

The Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) does not include verbal IQ and performance IQ scores, as provided in previous editions of the scale; rather, this edition provides comparisons among four index scores, allowing analysis of an individual's WAIS-IV performance in more discrete domains of cognitive ability. To supplement the pairwise index score comparisons included in the WAIS-IV manuals, this article describes the use of the mean of the four index scores (the average index score) as a baseline for analyzing index score variability and as a method for identifying strengths and weaknesses within an individual's index score pattern. Davis's formula was used to calculate critical values for the identification of index scores with a statistically significant difference from the average index score. Subsequent analysis of the WAIS-IV normative sample indicates that variability in performance at the index score level is not uncommon in the general population. More than 70% of individuals in the normative sample have at least one index score that differs significantly from their mean index score. This variability in index score performance appears to have little relationship to age or gender, but it is strongly related to the full-scale IQ.     

Individual differences in sensation seeking and attentional ability

Evidence is provided that high scores on the Zuckerman Sensation Seeking Scale are associated in the normal population with good focused-attention performance and poor distributed-attention performance. Focused-attention performance is assessed as the ability to select relevant information while ignoring irrelevant information, and distributed-attention performance is assessed as the ability to carry out concurrently two independent complex tasks. It is hypothesized that the observed disposition of attentional performance reflects differential patterns of arousal in individuals with high and low Sensation Seeking scores.     

Attribute Range and Response Range: Limits of Compatibility in Multiattribute Judgment

Previous research suggests that attributes may have greater effects on judgment when attribute scales and response scales are compatible. We examine a particular form of compatibility, similarity of ranges, and test between two theories of attribute range and response range effects. Two groups of subjects rated the overall class performance of students as described by two exam scores and an essay grade. An identical set of exam scores was presented in narrow and wide exam ranges. One group made performance ratings using a narrow response scale, and the other rated performance with a wide response scale. In both response range conditions, the effect of the common attribute levels was greater for the narrow exam range than for the wide exam range. This finding is inconsistent with a range-compatibility hypothesis which predicts that the effect of an attribute depends on the compatibility between attribute range and response range. Results are consistent with a range-frequency hypothesis in which the same attribute levels span a greater range of subjective values when presented in a narrow attribute range, regardless of the response scale.     

Cognitive performance inconsistency: intraindividual change and variability

Although many studies have examined inconsistency of cognitive performance, few have examined how inconsistency changes over time. 91 older adults (age 52 to 79) were tested weekly for 36 consecutive weeks on a series of multitrial memory speed (i.e., letter recognition) tasks. A number of multivariate techniques were used to examine how individuals' level of inconsistency changed across weeks and how this change was related to interindividual differences in age and intelligence. Results indicated that (a) inconsistency of performance is a construct separate from the underlying performance ability (i.e., memory speed); (b) inconsistency reduces exponentially with practice; (c) individuals with higher scores on tests of fluid general intelligence (G-sub(f)) reached lower asymptotic levels of inconsistency compared to lower scorers; and (d) after controlling for the systematic effects of practice, variability in inconsistency from week-to-week was more pronounced for individuals with lower G-sub(f) scores compared to individuals with higher scores.     

Preliminary findings with a new Vietnamese Stroop test.

Stroop performance was compared in primary Vietnamese- vs English-speaking individuals (age range 19-68 years), currently living in the USA. A modified Vietnamese Stroop task mimicked word, color, and interference effects of an English-language Stroop test. Stroop performance (items correctly completed and interference "cost") did not differ significantly between 30 Vietnamese Americans whose first language was Vietnamese (M age 34.3 yr.) vs 30 American-born individuals whose first language was English (M age 31.2 yr.). Expected performance decrements with aging were observed in English-language Stroop performance but not in Vietnamese-language Stroop performance, which instead exhibited a trend towards the opposite pattern. Unexpected group differences associated with age in Stroop performance may reflect subtle differences in task demands, not evident in simple category performance scores, or alternatively, cultural or neuropsychological differences in the study groups.     

Evidence of differential performance on simultaneous and sequential lineups for individuals with autism-spectrum traits

Given the impaired facial recognition of autistic individuals, we examined whether certain autism-spectrum traits affected eyewitness identification performance in a general adult population. In a sample of 120 individuals, levels of autism-spectrum traits were examined in relation to performance on simultaneous vs. sequential lineups using a signal detection paradigm. For simultaneous lineups, total Autism Spectrum Quotient (AQ) scores and scores on the excessive Attention to detail subscale were related to fewer hits and a more conservative response criterion. Attention to detail interacted with lineup type in that it was significantly related to improved discrimination accuracy and a less conservative response criterion in sequential lineups, but with impaired discrimination accuracy and a more conservative response criterion in simultaneous lineups. Higher AQ scores on the Attention switching subscale resulted in fewer hits, lower discrimination accuracy, and a more conservative response criterion with sequential lineups. Additionally, partial disguises led to more false alarms but not decreased accuracy. More thorough investigations of the effect of lineup type on identifications are needed before policy changes are recommended.     

Invariance of the weight parameter in information integration

The relative effect of each informational dimension in an information integration task is a joint function of its weight and the range of values over which it is varied. A method is developed for separating these two factors. Weights obtained by this method were compared across variations of stimulus range. Subjects rated the performance of students on the basis of midterm exam scores and final exam scores. For some subjects, the range of scores on the final exam was twice that on the midterm and the reverse was true for other subjects. An averaging model was shown to describe the results, and weights did not differ for different stimulus ranges. This was true for each of two instructional conditions: one in which a particular weighting strategy was prescribed and one in which there was no prescribed weighting. Students who were instructed to use a 2∶1 weighting were found to assign more than twice as much weight to the final as to the midterm.     

The tale is in the tail: an alternative hypothesis for psychophysical performance variability in dyslexia

Dyslexic groups have been reported to display poorer mean performance than groups of normal readers on a variety of psychophysical tasks. However, inspection of the distribution of individual scores for each group typically reveals that the majority of dyslexic observers actually perform within the normal range. Differences between group means often reflect the influence of a small number of dyslexic individuals who perform very poorly. While such findings are typically interpreted as evidence for specific perceptual deficiencies in dyslexia, caution in this approach is necessary. In this study we examined how general difficulties with task completion might manifest themselves in group psychophysical studies. Simulations of the effect of errant or inattentive trials on performance produced patterns of variability similar to those seen in dyslexic groups. Additionally, predicted relationships between the relative variability in dyslexic and control groups, and the magnitude of group differences bore close resemblance to the outcomes of a meta-analysis of empirical studies. These results suggest that general, nonsensory difficulties may underlie the poor performance of dyslexic groups on many psychophysical tasks. Implications and recommendations for future research are discussed.     

The impact of corrections for faking on the validity of noncognitive measures in selection settings

In selection research and practice, there have been many attempts to correct scores on noncognitive measures for applicants who may have faked their responses somehow. A related approach with more impact would be identifying and removing faking applicants from consideration for employment entirely, replacing them with high-scoring alternatives. The current study demonstrates that under typical conditions found in selection, even this latter approach has minimal impact on mean performance levels. Results indicate about .1 SD change in mean performance across a range of typical correlations between a faking measure and the criterion. Where trait scores were corrected only for suspected faking, and applicants not removed or replaced, the minimal impact the authors found on mean performance was reduced even further. By comparison, the impact of selection ratio and test validity is much larger across a range of realistic levels of selection ratios and validities. If selection researchers are interested only in maximizing predicted performance or validity, the use of faking measures to correct scores or remove applicants from further employment consideration will produce minimal effects.     

Spatial ability and handedness

The relationship between preferred handedness and spatial visualization was examined for 124 female and 229 male undergraduate students. Handedness and spatial ability were used in the design as continuous variables. Other variables examined were sex of subject and family history of sinistrality. Spatial ability was found to be systematically related to measured handedness, familial left-handedness, and sex of subject. Males outperformed females at all levels of handedness. The lowest performance was obtained by subjects who were either extremely left-handed or extremely right-handed. The highest scores were obtained by individuals with left-handed relatives and whose handedness scores were in the range considered mixed or slightly right-handed. The results suggest that decreased hemispheric specialization is associated with increased spatial ability.     

Social challenge and threat predict performance and cardiovascular responses during competitive video gaming

Individuals tend to compare themselves with others, and the results of these self-evaluations influence subsequent performance. When individuals perceive an advantage over their rivals (challenge-type response), they achieve higher levels of performance. According to the biopsychosocial model of challenge and threat, benefits of favourable appraisals are partly mediated by cardiovascular efficiency, which is increased by challenge and decreased by threat evaluations. In this study, we tested whether the biopsychosocial model can be extended to predict behavioural outcomes in esports. We expected that challenge-type evaluations would increase performance compared to threat-type evaluations. Eighty-two men were assigned to a challenge or threat group and completed three rounds of Counter-Strike: Global Offensive – a video game popular in esports. Individuals with the highest scores were awarded cash prizes. Cardiovascular markers of challenge and threat, cognitive appraisals, and game scores were recorded. We manipulated the social challenge and social threat evaluation by informing participants that their performance in the initial round was superior (challenge) or inferior (threat) compared with other gamers. We found that individuals with more gaming experience, believed they were better than other gamers, had higher heart rate and, in turn, achieved higher scores. These effects were related to initial situational appraisal at the baseline and were not boosted by feedback provided during the actual performance. These results are the first to document that social comparisons among gamers are accurate in the prediction of future physiological and behavioural outcomes. Furthermore, these findings emphasize that physiological responses mediate relationships between action-related cognitions and performance.     

The effect of time constraints and personality facets on general cognitive ability (GCA) assessment

General cognitive ability (GCA) is a recognized construct for predicting job performance and capacity to learn. However, it has recently been argued that the time constraints under which GCA is assessed might provoke test anxiety, which negatively biases GCA scores. This can then lead to erroneous rejection of qualified candidates in personnel hiring contexts. This paper aimed to investigate: (1) to what extent candidates’ GCA scores increase when tested without time constraints and the ability of this GCA score to predict job performance; and (2) the personality characteristics that hinder GCA test performance under time constraints. Results from two field studies conducted in an actual personnel selection context partially confirmed the hypotheses. They revealed that, aside from the improvement of all candidates’ GCA scores when time constraint was removed, only GCA assessed without time constraints predicts job performance. Furthermore, while all candidates’ scores were influenced by the time constraint condition, individuals who are anxious, low-impulse, low value-questioning and deliberating are more penalized by the time constraint condition of such testing and, thus, are more likely to be erroneously eliminated in a selection process.     

Potential performance theory (PPT): Describing a methodology for analyzing task performance

Based on potential performance theory (PPT), a methodological paradigm is developed that allows for individual-level analyses. The proposed methodology distinguishes among observed performance, strategy, and consistency, with the idea that changes in observed performance can be caused by changes in strategy or consistency. Equations are presented that allow the computation of strategy and consistency scores for groups and individuals, with the goal of enabling researchers to find the reasons why performance improves or does not improve. More specifically, people may (1) develop better strategies, (2) use them more consistently, (3) both, or (4) neither. It is even possible to have strategy—consistency trade-offs, as individuals focus on one at the expense of the other. Data obtained from an experiment illustrate these possibilities.     

Verbal Learning Strategies of Adolescents and Adults with the Syndrome of Nonverbal Learning Disabilities

Abstract

Although many psychometric studies of individuals with the syndrome of nonverbal learning disabilities (NLD) have been conducted, one relatively neglected area has been the study of their performance on explicit verbal memory measures. We examined the performance of adolescents and adults with NLD on the California Verbal Learning Test, a measure allowing analysis of self-initiated learning strategies, and compared their performance to age- and Full Scale IQ-matched verbal learning-disabled (VLD) controls. Mean performance of the NLD sample on the semantic clustering index fell one standard deviation below the normative mean, whereas their serial clustering score was within normal limits. Additionally, the serial clustering score for our NLD sample was significantly greater than their semantic clustering score, suggesting that these individuals are more likely to spontaneously employ serial verbal learning strategies as opposed to those that are semantically driven. This difference in serial versus semantic clustering scores was not seen in our VLD controls, who performed equally well, and within normal limits, on both indices.     

Fear and anxiety as separable emotions: an investigation of the revised reinforcement sensitivity theory of personality

The Gray and McNaughton (2000) theory draws on a wide range of animal data to hypothesize that the emotions of fear and anxiety are separable. The authors tested their hypothesis in two studies. The first study examined associations between scores on questionnaire measures of fear, anxiety, and neuroticism; correlational analysis revealed that fear and anxiety are not interchangeable constructs. The second study examined associations between scores on questionnaire measures of fear/anxiety and performance in a military training setting; regression analysis revealed that fear captured significant variance in performance that was not shared with anxiety. These results imply that hypotheses derived from nonhuman animal data may hold important implications for understanding human emotion and motivation, especially in relation to fear and anxiety.     

Criterion Validity and Practical Utility of the Minnesota Multiphasic Personality Inventory–2–Restructured Form (MMPI–2–RF) in Assessments of Police Officer Candidates

Minnesota Multiphasic Personality Inventory–2–Restructured Form scores for 145 male police officer candidates were compared with supervisor ratings of field performance and problem behaviors during their initial probationary period. Results indicated that the officers produced meaningfully lower and less variant substantive scale scores compared to the general population. After applying a statistical correction for range restriction, substantive scale scores from all domains assessed by the inventory demonstrated moderate to large correlations with performance criteria. The practical significance of these results was assessed with relative risk ratio analyses that examined the utility of specific cutoffs on scales demonstrating associations with performance criteria.     

The Effect of Experience on the Goal-Setting Behavior of Type A and Type B Individuals

The effect of experience on the goal-setting behavior of Type A and Type B individuals was assessed using anagram tasks. Sixty men and 60 women were administered the Jenkins Activity Survey as well as a questionnaire assessing their previous experience with anagram tasks. Before each of three anagram trials, subjects set a performance goal and indicated how certain they were that they could reach that goal. The analyses indicated that Type A men had the largest differences between performance goals and actual performance, even though men, in general, were more certain that they would reach their goals. Differences across trials, however, decreased for all individuals. Men with the most prior self-reported experience were least satisfied with their performance. Of interest was the finding that Type B women had higher difference scores than did Type A women.     

Performance-psychologic cross-sectional study of young schizophrenic patients with a subchronic and chronic disease course

According to ICD-9 and DSM-III-R-criteria 14 subchronic schizophrenic male patients (duration of illness less than 2 years) and 17 chronically ill male schizophrenics (duration of illness between 5 to 12 years) matched for sex, age, education, type of illness, and medication were with the aid of 4 tests investigated with respect to time characteristics of performance parameters. Whereas subchronic patients revealed performance scores within the normal range of reference scores, chronically ill patients showed dissociative variations in performance (high scores in reasoning, low scores in speed factor). This can be interpreted as instability of brain functioning which characterizes schizophrenics suffering from a long duration of illness. Correlations between prolonged reactions to "crossmodal" choices and subjective basic symptoms in subchronic patients are hints at well established introspection ability of self regarded complaints.