Assessment of cognitive control in psychopathic and normal prisoners

It has been suggested that psychopaths exhibit specific deficits in cognitive processes associated with frontal lobe functioning. There is also evidence which indicates that level of intelligence may influence expression of impulse control among psychopaths. The present study investigated these hypotheses by comparing groups of 44 psychopaths and 14 normal controls selected from a sample of incarcerated male felons using Minnesota Multiphasic Personality Inventory (MMPI)-defined criteria. Dependent variables included several measures of cognitive flexibility, perseveration, and impulsiveness. Compared to normal controls, psychopaths showed no greater tendencies to persist in incorrect responding, disregard cues suggesting the need to modify behaviors, or proceed impulsively in problem solving. Level of intelligence was found to be a moderator variable influencing performance for psychopaths and normal controls. Results suggest that deficits in cognitive functioning are not necessarily characteristic of psychopaths across situations.     

Behavior and personality assessment in men labeled adaptive sociopaths

Few efforts have been made to understand antisocial-prone individuals who maintain adaptive functioning. This study identified a sample of potentially deviant but adaptively functioning persons to determine whether they differed significantly from their more conforming peers. A small sample of men was selected by Minnesota Multiphasic Personality Inventory (MMPI)-defined criteria for sociopathy and compared with MMPI-defined normals of similar ages, backgrounds, and intelligence. Response variables were those cited in the literature as characteristic of sociopathic psychopathology and included measures of abilities to plan ahead and inhibit impulsiveness, sensation seeking, interpersonal performance and style, and behavior conformity. Men labeled adaptive sociopaths showed greater impulsiveness and needs for experience seeking, earned lower scores on measures of socialization and self-control, and admitted greater adolescent behavior deviance. They were not shown to be less empathetic or less able to relate interpersonally in interview. The potential role of socially constructive self-determined goals and tangible vocational rewards as mediators of adaptive behavior are discussed in terms of overcoming antisocial tendencies and attenuation of behavior disinhibition.     

Quest: A Bayesian adaptive psychometric method

An adaptive psychometric procedure that places each trial at the current most probable Bayesian estimate of threshold is described. The procedure takes advantage of the common finding that the human psychometric function is invariant in form when expressed as a function of log intensity. The procedure is simple, fast, and efficient, and may be easily implemented on any computer.     

Transfer of training of a new linguistic contrast in voicing

The present study examined the plasticity of the human perceptual system by means of laboratory training procedures designed to modify the perception of the voicing dimension in synthetic speech stimuli. Although the results of earlier laboratory training studies have been ambiguous, recently Pisoni, Aslin, Perey, and Hennessy (1982) have succeeded in altering the perception of labial stop consonants from a two-way contrast in voicing to a three-way contrast. The present study extended these initial results by demonstrating that experience gained from discrimination training on one place of articulation (e.g., labial) can be transferred to another place of articulation (e.g., alveolar) without any additional training on the specific test stimuli. Quantitative analyses of the identification functions showed that the new perceptual categories were stable and displayed well-defined labeling boundaries between categories. Taken together with the earlier findings, these results imply a greater degree of plasticity in the adult speech processing system than has generally been acknowledged in past studies.     

Expectation and autokinesis

The reported direction of autokinesis for naive observers is not biased by gaze deviations of 22.5 deg of arc. However, instructions to expect either “inward” or “outward” movement produce reports of autokinetic movement that are progressively biased in the expected direction. Instructions to expect “more” or “less” movement resulted in a decrease in the reported duration of apparent movement for the “less” group but no change for the “more” group. Response bias is not considered to play a role in these results. The results are discussed in terms of fixational bias and selective attention mechanisms of autokinesis.     

Scaling apparent distance in a large open field: some new data

Judged distance in a large open field, scaled by the method of magnitude estimation, is related to physical distance by a power function with an exponent smaller than unity. The exponents obtained with two ranges of distance were not affected by the availability of a standard. The mean exponent for all 80 individual power functions was 0.86, with a standard deviation of 0.11.     

Quantitative amino acid determination in the serum and cerebrospinal fluid in endogenous depressions

The levels of 20 amino acids were measured in the plasma and cerbrospinal fluid of 41 patients with endogenic depressions. The plasma levels of 12 amino acids were found to be significantly lower in the patients than in the control group, but cerebrospinal fluid levels were significantly lower only in the case of taurine, glutamine, phenylalanine and aginine. Comparison of the same amino acid levels in treated and non-treated patients showed that serine and alpha-aminobutyric acid serum concentrations were higher in the nontreated patients. The tyrosine and phenylalanine levels in the cerebrospinal fluid of the patients who had received medicamentous treatment were higher than in the other group.     

Acquiring conjunctive concepts: When and why does feature frequency affect feature identification?

According to frequency theories of concept attainment, acquisition of rule-governed concepts depends on discriminating relevant from irrelevant stimulus features on the basis of their respective frequencies of occurrence. Depending on the theorist, the critical frequency counts may be based on occurrence in all stimuli or on occurrence in positive instances only. Experiment 1 held frequency in positive instances constant and varied the frequency of irrelevant features in the negative category. High frequency was associated with impaired performance, but only when concept problems started with a negative instance. Experiment 2 demonstrated that some previous findings in the literature that were thought to support frequency theory also depended on problems starting with a negative instance. These findings are not easily reconciled with existing frequency theories. We attribute our results to high intercategory similarity, which is a correlate of high frequency of irrelevant features. In the context of a hypothesis-testing theory, we propose that a negative start stimulus proactively interferes with memory for information in the initial positive instance and that the extent of the interference depends on how similar negative instances are to positive instances.     

On the conflict between logic and belief in syllogistic reasoning

Three experiments are reported that investigate the weighting attached to logic and belief in syllogistic reasoning. Substantial belief biases were observed despite controls for possible conversions of the premises. Equally substantial effects of logic were observed despite controls for two possible response biases. A consistent interaction between belief and logic was also recorded; belief bias was more marked on invalid than on valid syllogisms. In all experiments, verbal protocols were recorded and analyzed. These protocols are interpreted in some cases as providing rationalizations for prejudiced decisions and, in other cases, as reflecting a genuine process of premise to conclusion reasoning. In the latter cases, belief bias was minimal but still present. Similarly, even subjects who focus primarily on the conclusion are influenced to an extent by the logic. Thus a conflict between logic and belief is observed throughout, but at several levels of extent.     

Central auditory processing : III. The “cocktail party” effect and anterior temporal lobectomy

The capacity to selectively attend to only one of multiple, spatially separated, simultaneous sound sources—the “cocktail party” effect—was evaluated in normal subjects and in those with anterior temporal lobectomy using common environmental sounds. A significant deficit in this capacity was observed for those stimuli located on the side of space contralateral to the lobectomy, a finding consistent with the hypothesis that within each anterior temporal lobe is a mechanism that is normally capable of enhancing the perceptual salience of one acoustic stimulus on the opposite side of space, when other sound sources are present on that side. Damage to this mechanism also appears to be associated with a deficit of spatial localization for sounds contralateral to the lesion.