Individual and group differences in intelligence and speed of information processing

A battery of eight different reaction time (RT) tests, measuring the speed with which individuals perform various elementary cognitive processes, and a group test of scholastic aptitude (the Armed Services Vocational Aptitude Battery, ASVAB) were given to 50 black and 56 white male vocational college students. The regression of the general factor scores of the ASVAB on the RT measures yielded a shrunken multiple correlation of 0.465. Although discriminant analyses, when applied separately to the ASVAB subtests and to the RT variables, showed highly comparable overall discrimination (over 70% correct classification) between the black and white groups, factor scores derived from the general factor (labeled ‘speed of information processing’) of the RT battery show only about one-third as large a mean black-white difference as the mean group difference on the general factor scores derived from the ASVAB. Comparisons were also made between the 106 vocational college students and 100 university students of higher average academic aptitude who had previously been tested on the same RT battery (Vernon, 1983a). These groups showed marked differences on the RT variables, the largest differences occuring on the tests that required more complex cognitive processing. The more complex RT tests also correlate most highly with the psychometric measures of ability within each group. The results are consistent with the hypothesis that individual differences and the mean differences between groups in psychometric abilities and scholastic achievement are related to differences in the speed of information processing as measured in elementary cognitive tasks.     

The contribution of “cool” and “hot” components of decision-making in adolescence: Implications for developmental psychopathology

Impairments in either “cool” or “hot” processes may represent two pathways to deficient decision-making. Whereas cool processes are associated with cognitive and rational decisions, hot processes are associated with emotional, affective, and visceral processes. In this study, 168 boys were administered a card-playing task at ages 13 and 14 years to assess response perseveration. This task was designed to initially reward playing and gradually associate playing with punishment. Measures of subjective ordering (cool processes) and neuroticism (hot processes) at age 13 years were used to examine how these individual characteristics relate to perseveration over time. A decrease in perseveration from age 13 to 14 was associated with cool processes whereas hot processes were associated with response perseveration only over time. A complementary but simultaneous assessment of cool and hot processes, such as neuropsychological and personality tests, could facilitate treatment planning of children with behavioral problems.     

Verbal probabilities: Ambiguous, context-dependent, or both?

To investigate the communication value of verbal probabilistic phrases, like “possibly,” “probably,” and “perhaps,” three experiments were conducted. Subjects were asked to judge the degree of probability expressed by such phrases in different contexts: in sentences reflecting opinions on current events, in a medical discussion of treatment effectiveness, and in videotaped news reports. Judgments of degree of probability were performed in the first study on a 0–100% probability scale and in the other two on 7-point rating scales. Results indicated that different contexts influence the interpretation of probability terms and in many cases, but not always, lead to higher between-subject variability than when the terms are judged in isolation, presumably because the interpretation of probability terms tends to be correlated with the judges' personal opinions on the topics. Special communication problems arise from the fact that most people are not fully aware of the ambiguity of these phrases and underestimate the variability of such ratings in the general population. Miscommunication between experts and the general public was illustrated by answers to a questionnaire given to general medical practitioners and to parents of small children. The latter preferred numerical probabilities to words, but thinking from an individual-oriented perspective, they often misunderstood the intended statistical meanings.     

Language skills in developmentally disabled children

Language measures of receptive and expressive vocabulary, story telling, and immediate verbal memory, as well as two perceptual tests, were administered to a group of developmentally disabled children, and three groups of normal children, one matched for chronological age, one for mean length of utterance, and one for performance on one of the perceptual tests. When diagnostic subgroups of “autism,” “childhood schizophrenia,” and “other severe disturbance” were formed using standard diagnostic tools, no language differences were found between diagnostic subgroups. When compared with the normal control groups, many of the language skills of the entire group of disabled children, and of the autistic children alone, were rather evenly delayed, showing only a relative sparing of the naming function, and a relative deficit on immediate verbal memory. Furthermore, a high correlation was found in a small subsample between the difficulty levels of morphemes in the disabled children and those reported for young normal children. Experienced special-education and early-childhood teachers could not discriminate the stories of the disabled children from those of young normal children. Analysis of the disabled children's error strategies, however, revealed features of their language not found in normal children's language: (1) extreme perseveration in test answers and stories, (2) attention to minor features of test stimuli, and (3) failure to adopt alternate, flexible communicative strategies. We conclude that the language acquisition of the developmentally disabled children is delayed but not deviant in its semantic and syntactic competence, and that current diagnostic practice does not differentiate linguistically distinct subgroups. We further argue that where developmentally disabled children do exhibit aberrant features of language, such deviance parallels similar features in other cognitive skills, and is not unique to language.     

Trait anxiety, defensiveness and selective processing of threat: an investigation using two measures of attentional bias

Attentional biases for threat were examined in a non-clinical sample (N=60), with each participant tested on both the modified Stroop colour-naming and dot probe tasks. Three groups were selected on the basis of trait anxiety and social desirability scale (SDS) scores: “low anxiety” (LA: low trait, low SDS), “repressor” (REP: low trait, high SDS) and “high anxiety” (HA: high trait, low SDS). Results from the colour-naming task suggested that high levels of defensiveness (in combination with low trait anxiety) were associated with greater avoidance of threat. The REP group showed less interference in colour-naming threat than neutral words; whereas the HA group showed increased interference due to threat words. On the dot probe task, there was a general tendency for this non-clinical sample as a whole to show avoidance of social threat relative to neutral words, but there was no bias for physical threat words. Avoidance of social threat was significant only within the REP group. No relationships were found between the measures of cognitive bias from the two tasks, suggesting different underlying mechanisms. Results are discussed in relation to previous findings and theoretical views of the effects of anxiety and defensiveness on the processing of threat.     

Assumptions underlying psychological testing

Tests purporting to reflect the learning aptitudes of school children differ much more than generally is recognized. However, error in assesing such learning aptitude inheres much more in the users of the tests than in the tests themselves. Assumptions fundamental to such assessment, or even testing, are considered. It is particularly important that the assessor, or tester, constantly be sensitive to the nature of the relationship between the psychological demands of test items or tests and the learning demands confronting the child. Even tests that generally are grossly or crudely used often can yield psychoeducationally meaninful information if their results are differentially perceived in terms of the light they throw on the psychological operations fundamental to learning, “process,” as contrasted with that thrown on the results of the functioning of such operations, “product.”     

Development of a Cyber/Information Technology Knowledge Test for Military Enlisted Technical Training Qualification

An Armed Services Vocational Aptitude Battery (ASVAB) Review Panel, with expertise in personnel selection, job classification, psychometrics, and cognitive psychology developed recommendations for changes to the military enlistment test battery. One recommendation was to develop and evaluate a test of cyber/information and communications technology literacy to supplement current ASVAB content. This article summarizes a multiphased Cyber Test development process: (a) a review of information/computer technology literacy definitions and measures, (b) development and pilot testing of a cyber knowledge measure, (c) validation of test scores against final school grades (FSGs) for selected technical training courses, (d) development of an operational reporting metric and subgroup norms, and (e) examination of construct validity. Results indicate the Cyber Test has predictive validity versus technical training school grades and incremental validity comparable to the ASVAB technical knowledge tests when used with the ASVAB Armed Forces Qualification Test (AFQT) verbal/math composite as a baseline.     

Between- versus within-family factor analyses of cognitive abilities

Confirmatory factor analyses of the 15 cognitive abilities tests from the Hawaii Family Study of Cognition were conducted on between-family (BF) means and within-family (WF) differences for 370 AEA (Americans of European ancestry) and 116 AJA (Americans of Japanese ancestry) sibling pairs. Difference chi-square significance tests, goodness-of-fit indices, and congruence coefficients for the estimated loadings on four specific cognitive abilities factors and on the second-order general intelligence factor nearly all indicated that the between-family factor structures were not significantly different from the within-family structures for both AEA and AJA siblings (the AEA and AJA structures were also not significantly different). The similarity of the BF and WF structures suggests that the genetic and environmental influences underlying cognitive abilities are “intrinsic” in nature, that is, not just due to between-family differences in culture, status, values, and fortuitous cross-assortative mating.     

A study of alpha hemispheric asymmetries for verbal and nonverbal stimuli in males and females

The alpha hemispheric asymmetries of males and females were examined with electroencephalographic (EEG) techniques during exposure to connected speech and nonlinguistic stimuli. The subject selection controlled for familial handedness and each subject was administered the Block Design and Vocabulary Subtests of the WAIS as a general measure of “visual-spatial” and “verbal” ability. The results showed that there was less alpha in the right hemisphere for nonverbal tasks and less alpha in the left hemisphere for verbal tasks. The females showed significantly more “lateralization” during the tasks as compared to the males. The results are discussed in terms of processing differences and the possible effects of subject variables, stimulus mode, stimulus presentation, and task requirements on neurolinguistic research results.     

Cognitive Coping Tool Kit for Psychosis: Development of a Group-Based Curriculum

This article outlines an 8-week curriculum that was created to help outpatients develop cognitive and behavioral skills for coping with delusions and hallucinations as well as to reduce patients’ comorbid subjective levels of distress (e.g., depression, anxiety). The manualized protocol consisted of psychoeducation and training in a variety of CBT skills that have shown promise in treating individuals with residual psychosis, using recovery-oriented “naturalistic” methods and culminating in the creation of an individualized “tool kit” of cognitive coping resources. A preliminary study of the effectiveness of this brief group-based CBT program for outpatients with chronic, residual symptoms of schizophrenia was conducted. Participants were 24 outpatients diagnosed with schizophrenia spectrum disorders who were stable on medications and connected to case management community follow-up. The Positive and Negative Syndrome Scale for Schizophrenia interview and the Symptom Checklist-90 self-report symptom scales were administered pre- and post-intervention. The results suggest that there were significant improvements in psychotic symptoms and self-reported distress from pre- to posttreatment.     

Disentangling the course of epistemic development: parsing knowledge by epistemic content

Over the past three decades, research into the developmental course by means of which persons come to an increasingly mature conception of the knowing process has yielded an highly defracted picture. Despite some concert of opinion about the general bill of particulars, what remains deeply problematic is the increasingly radical disagreement that has arisen regarding the ages at which major milestones in the course of epistemic development are said to be reached. As a way of making some sense of these competing claims, it is argued that the emerging insight that knowledge is ineluctably shaped by those doing the knowing (i.e., that there is an unavoidable “world-to-mind direction of fit” (J.R. Searle, Intentionality: An Essay in the Philosophy of Mind, Cambridge University Press, Cambridge, 1983) between things in the world and the manner of their understanding) does not arrive in a single piece. Instead, as the data presented here help to illustrate, an appreciation of the constructed character of knowledge more commonly arrives piecemeal and at different ontogenetic moments, the times of which are governed by the place that different objects of knowledge occupy along an envisioned continuum of diverse epistemic contents. On this account, not all “facts of the matter” are ordinarily seen to occupy the same epistemic footing. Rather, some so-called facts are commonly understood to be of an “institutional” sort, where “representational” diversity is early expected and widely tolerated. By contrast, other objects of knowledge are imagined to be more like “brute” facts that, on some less mature readings, fully escape the clutches of subjective opinion. Viewed against the backcloth of this proposed continuum, a developmental sequence hypothesized according to which growing persons first come to view “institutional” facts as humanly constructed before subsequently coming to a similar view about presumptively “brute” facts. To test this hypothesis, 242 young persons were administered a paper and pencil measure of epistemic reasoning (the EDQ). Results strongly support the hypothesis that respondents understood the interpretive nature of beliefs about “institutional” facts at an earlier age than so-called “brute” facts.     

Post-hypnotic amnesia as disrupted retrieval: A role-playing paradigm

Evans and Kihlstrom (1973) have proposed that the phenomenon of “disrupted retrieval” may be an unobtrusive measure of post-hypnotic amnesia not readily explicable in terms of role-playing or task motivational paradigms of hypnotic behaviour. An attempt was made to test the viability of a role-playing explanation of hypnotic disrupted retrieval by giving equivalent role-playing instructions to carry out hypnosis scale suggestions to unhypnotised subjects. When given the instruction to “pretend” to remember on a few items, unhypnotised subjects recalled items in a random and disorganised manner similar to Evans' and Kilstrom's “hypnotised” subjects; when not given this instruction the unhypnotised subjects showed the sequential organised recall of Evan's and Kihlstrom's hypnotically insusceptible subjects. It was concluded that the phenomenon of disrupted retrieval in post-hypnotic amnesia can readily be explained in terms of the role-playing behaviour implicitly demanded of hypnotically susceptible subjects.     

Locus of control and the perception of freedom in an agent of reinforcement

Internals and externals observed a staged videotape presentation that portrayed a “teacher” and a “learner” engaging in a 20-item anagrams task. For externals, any variability (10, 50, and 90% schedule) in the reinforcing behavior of the “teacher” (agent of reinforcement) resulted in significantly greater perceived freedom than when no variability (0 and 100% schedule) occurred in behavior. For internals, perceived freedom was a negative linear function of the amount of reinforcement administered. Internals indicated that they could influence the behavior of the “teacher” in all reinforcement conditions, whereas externals indicated that they could influence only the “teachers” in the variable reinforcement conditions. It was concluded that greater freedom is attributed to a person whose behavior is perceived as congruent with the person's inner disposition.     

Stimulus Characteristics Determine Processing Approach on Random Array Letter-Cancellation Tasks

Target-to-distractor ratio strongly influences performance on typical random array letter cancellation tasks, suggesting that a “controlled” processing approach is used. This study was designed to determine whether “automatic” processing could be also demonstrated in the random array cancellation paradigm by changing the perceptual characteristics of the stimuli. Thirty-two healthy subjects sequentially performed four random array cancellation tasks with 50 and 100 stimuli. The letters “I” or “O' were targets and “L” served as the distractor. Performance was measured by the number of correctly canceled targets divided by the time to completion, corrected for accuracy. There was a strong effect of the number of stimuli on forms using I targets (p< .00001), but not for O's (p= .15) Performance scores were lower for I target forms than for O targets. These findings demonstrate that performance approximating “automatic” processing can also be elicited on clinically useful, office-based, or bedside tests such as random array cancellation.     

Cognitive epidemiology: With emphasis on untangling cognitive ability and socioeconomic status

This commentary touches on practical, public policy, and social science domains informed by cognitive epidemiology while pulling together common themes running through this important special issue. As is made clear in the contributions assembled here, and others (Deary, Whalley, & Starr, 2009; Gottfredson, 2004; Lubinski & Humphreys, 1992, 1997), social scientists and practitioners cannot afford to neglect cognitive ability when modeling epidemiological and health care phenomena. However, given the dominant concern about the confounding of general cognitive ability (GCA) and socioeconomic status (SES), and the extent to which SES is frequently seen as the primary cause of health disparities (while GCA is neglected as a possible influence in epidemiology and health psychology), some methodological applications for untangling the relative influences of GCA and SES are reviewed. In addition, cognitive epidemiology is placed in a broader context: Just as cognitive epidemiology facilitates an understanding of pathology (“at risk” populations, and ways to attenuate undesirable personal and social conditions), it may also enrich our understanding of optimal functioning (“at promise” populations, and ways to identify and nurture the human and social capital needed to develop innovations for saving lives, economies, and perhaps even our planet). Finally, while GCA is likely the most important dimension in the study of individual differences for modeling healthy behaviors and outcomes, other relatively independent dimensions of psychological diversity do add value (Krueger, Caspi, & Moffitt, 2000). For example, compliance has at least two psychological components: a “can do” competency component (ability) and a “will do” motivational component (conscientiousness). Ultimately, developing and modeling healthy behaviors, interpersonal environments, and medical maladies are best accomplished by teaming multiple dimensions of human individuality.     

Personal epistemology and theory of mind: deciphering young children's beliefs about knowledge and knowing

The beliefs that individuals hold about knowledge and knowing have been the focus of a growing body of work on “personal epistemology.” There has been general agreement among researchers about a developmental trajectory of epistemological understanding that takes place in adolescence and adulthood. Rarely has this research included children, however, and we know little about the origins of epistemological awareness or its early development. A separate group of researchers have investigated children's “theory of mind,” or the ability to understand others’ beliefs, actions, and desires, with primary attention to the onset of this cognitive achievement between the ages of 3 and 5. This article reviews the theoretical foundation for a proposed relation between these constructs, and reports on an exploratory investigation with 3–5 year olds, in which epistemological level was significantly related to theory of mind ability. Results are discussed in relation to a general timeline depicting the development of children's beliefs about knowledge and knowing, a process that involves an ongoing tension between objective and subjective perspectives. We propose that the trajectory of epistemological development be expanded to include an initial period of egocentric subjectivity that characterizes epistemological thinking prior to the achievement of theory of mind.     

Personality, anxiety and functional dysphonia

Psychological factors are considered for the predisposition and perpetuation of functional dysphonia. In the present study 61 patients with functional dysphonia were compared with 61 healthy controls, matched by age, sex, and occupation with respect to Cloninger’s personality model, mood, and anxiety.The patients with functional dysphonia presented significantly higher scores than the healthy controls with respect to “harm avoidance” (HA); depressive symptoms; symptoms of unspecific and general anxiety; symptoms of specific anxiety concerning “health”, “illness”, and “extraversion versus introversion”. No significant differences were found in “novelty seeking” (NS), “reward dependence” (RD), “persistence” (PE), or in state-anxiety and anxiety of social situations. These results were found considering univariate and multivariate analyses and confirm the relationship of psychological factors such as personality traits, mood, and anxiety on one hand and conversion disorder in general and functional dysphonia in particular on the other hand. This important relationship should be considered in the diagnostic and therapeutic interventions of functional dysphonia.     

The “Poffenberger” and “Dimond” Paradigms: Interrelated Approaches to the Study of Interhemispheric Dynamics?

Brown and Jeeves (1993) found that an evoked potential estimate of interhemispheric transfer time, from the left to the right hemisphere, correlated negatively with a bilateral field advantage (BFA) in a response-choice letter matching task. We implemented a go no-go dot size matching task to determine whether the crossed-uncrossed difference (CUD) in reaction time, commission errors and omission errors (estimates of the “cost” of interhemispheric transfer) would correlate with BFAs in data from the same experiment and whether the type of decision (“same” versus “different”) would modulate the CUDs and/or BFAs. Sixteen normal right-handed subjects were tested. The CUDs were negatively correlated with the BFAs. Canonical correlation analysis of this set of relations was highly significant (r= .95). Estimates of left-to-right relay were far more strongly related to BFA (p= .0001) than were estimates of right-to-left relay (p= .03). “Same” decisions yielded a unilateral field advantage and “different” decisions a bilateral field advantage in omission error data, this crossed interaction reaching significance. More efficient interhemispheric relay favored BFAs, i.e., strongly suggesting in such cases an advantage of interhemispheric over intrahemispheric integration. This effect appeared to be markedly asymmetric. Furthermore, resource sharing within and between the hemispheres was a function of the “same” versus “different” dimensions of the decision to be made, especially in omission errors. The opposite dissociation occurred less markedly in the reaction times, this double dissociation reaching significance, revealing presence of a subtle speed–accuracy trade-off in interhemispheric dynamics.     

Social desirability response bias as one source of the discrepancy between subjective weights and regression weights

This study of the judgment process investigated whether social desirability response bias is more closely associated with directly weighted subjective weights than less directly assessed regression weights. Graduating college students indicated their preferences for 11 job characteristics in four different tasks: (a) a statistical weighting task completed honestly, (b) a statistical weighting task completed to “look good” to a recruiter, (c) a subjective weighting task completed honestly, and (d) a subjective weighting task completed to “look good” to a recruiter. Predicted judgments were calculated from the weights obtained in each condition. Pearson correlation coefficients using these predicted judgments were computed between conditions; the relationship between the honest and positive impression predicted judgments derived from subjective weights was significantly greater than the relationship between honest and positive impression predicted judgments derived from regression weights for 19 of 23 participants. It was concluded that social desirability response bias was more closely related to subjective weights than to regression Weights.     

Study of the energy correlates in the learning of a complex self-paced cyclical skill

This study examines changes in movement parameters and energy expense during the learning of a cyclical task performed on a “ski simulator”. Five subjects performed five training sessions (each of four 4-minute learning periods separated by a 4-minute rest) and then took a post-test one week later. The instructions were to make movements which were “as wide and frequent as possible”. The subjects were filmed on videotape and their oxygen intake was measured. Movement amplitude, movement frequency, oxygen intake, and a “movement cost” index were calculated. The results indicated a significant increase in movement amplitude and oxygen intake and a decrease in movement cost. The movement frequency of all subjects tended towards the same final value. Two simultaneous changes could occur, with large individual differences: an increase in energy expense due to the increase in the amount of work done, a decrease in energy expense due to the increase in movement economy.