Amir Poreh

Facial recognition in hypothetically schizotypic college students : the role of generalized poor performance

This study investigated facial and facial affect recognition abilities among hypothetically schizotypic college men, defined by high scores on the perceptual aberration, magical ideation, and schizotypy scales. Groups were commensurate in age, handedness, and general intelligence. Multiple analyses of variance revealed that high-scoring subjects, relative to control subjects, made more errors on a facial affect recognition task (F = 5.32, p < .05) and on a facial recognition task (F = 8.5, p < .01). Additional multiple analyses of covariance using the face recognition scores as the covariant found no group differences. These results extend similar findings in schizophrenic individuals to hypothetically schizotypic college students, and suggest that both groups exhibit affect recognition deficits that reflect generalized attention and vigilance deficits rather than a specific emotion recognition deficit.

Czech Version of the Trail Making Test: Normative Data and Clinical Utility

The Trail Making Test (TMT) comprises two psychomotor tasks that measure a wide range of visual-perceptual and executive functions. The purpose of this study was to provide Czech normative data and to examine the relationship between derived TMT indices and demographic variables. The TMT was administered to 421 healthy adults. Two clinical groups (n = 126) were evaluated to investigate the clinical utility of the TMT-derived scores: amnestic mild cognitive impairment (n = 90) and Alzheimers disease (n = 36). Statistical analyses showed that age and education, but not gender, were significantly associated with TMT completion times and derived scores. Of all the indices, only the TMT ratio score was insensitive to age. We present normative values for the Czech version of the TMT, providing a reference for measuring individual performance in native Czech speakers. Moreover, we found that accuracy on the TMT was improved with the attenuation of age.

The Relationship Between Self-Efficacy and Disability in Chronic Low Back Pain Patients

This study examined the reliability of an adapted version of the Arthritis Self-Efficacy Scale in a sample of 59 chronic low back pain patients. The present study also investigated the relationship between self-efficacy and measures of disability. Regression analyses indicated a significant negative relationship between self-efficacy and low back pain disability. That is, patients who report higher levels of self-efficacy have higher activity levels (R2=0.34,P<0.01), work more hours (R2=0.25,P<0.01), and have lower levels of psychological distress (R2=0.29,P<0.01), pain severity (R2=0.46,P<0.01), and pain behavior (R2=0.27,P<0.01) after controlling for the demographic variables of gender, duration of back pain, and having a lawyer on retainer. The results support the use of the Back Pain Self-Efficacy Scale (BPSES) as a general measure of self-efficacy in the chronic low back pain population.

Creative thinking abilities and hemispheric asymmetry in schizotypal college students

Two groups of college students that scored high (N=25) and low (N=60) on a schizotypal personality index based on the Perceptual Aberration, Magical Thinking, and Schizotypal Personality Scales, were tested for hemisphericity using a dichotic listening task and completed the Torrance Test of Creative Thinking. The schizotypy scales correlated with high scores on the nonverbal portion of the creativity tests and with a left ear preference to dichotically presented verbal stimuli. The Torrance Test of Creative Thinking did not correlate, however, with hemispheric asymmetry. These results clarify the relationship between schizotypy and creating thinking abilities but fail in establishing the role of hemispheric asymmetry in the production of creative thinking ideas.

Reexamination of executive functions in psychosis-prone college students

Abstract The verbal and nonverbal executive functions of 19 psychosis-prone and 19 normal controls were examined. Subjects completed the WAIS-R Block Design and Vocabulary subtests, the Wisconsin Card Sorting Test (WCST), the Controlled Word Association Test (COWAT), the Booklet Category Test (BCT), the Design Fluency Test (DFT), and the Trail Making Test (TMT) parts A and B. Analysis of the performance patterns on these measures revealed that psychosis-prone college students exhibit relative deficits on all of the above verbal and nonverbal measures of executive functions but not on measures of nonexecutive functions. These findings confirm previously reported studies that have correlated executive functions and pre-frontal structural deficits with schizotypal personality traits and provide additional support for the association between neuropsychological functions and certain personality traits.

Impulsivity, Aggression and Suicide Risk among Male Schizophrenia Patients

Introduction: Impulsivity has been shown to be a major variable in the etiology of suicide and aggression, but has not been researched as much in the schizophrenic population, which is characterized by serious suicide and aggression risks. Methods: 68 male schizophrenia patients responded to a battery of measures including the Positive and Negative Syndrome Scale (PANSS), the impulsivity control scale (IS), the Suicide Risk Scale (SRS) and the Overt Aggression Scale. Results: We divided our subjects into those who received scores above and below the median on the IS. The high- impulsivity group had higher present and past rates of suicidal ideation and showed a trend for more lifetime suicidal attempts than the low-impulsivity group. The impulsivity score correlated positively with the SRS score and with some of the scores of the PANSS (the positive symptoms score, the general psychopathology score and the total score). A multiple regression analysis revealed that an older age, higher levels of aggression, high impulsivity and an elevated score on the general psychopathology subscale of the PANSS contributed positively and significantly to the explained variance of the SRS. Conclusions: Our study supports the contention that high impulsivity in schizophrenia patients is significant in the etiology of suicide in schizophrenia. However, the relationship between impulsivity and aggression in schizophrenia patients, and also the amelioration of impulsivity by pharmacological interventions, require further study.

Reexamination of mixed handedness in psychosis-prone college students

Abstract The hand preference of psychosis-prone college students was examined in two separate studies using the Annett Handedness Questionnaire. The first sample, subjects who completed the Perceptual Aberration and Magical Ideation scales ( n =895), confirmed Chapman and Chapmans (1987a) report of greater mixed handedness in psychosis-prone college students. The second sample, 214 college students who completed the Schizotypal Personality Questionnaire (SPQ), did not support Kim, Raine, Triphon and Greens (1992) findings of a correlation between mixed handedness and certain SPQ scales. The results of the current study are discussed in light of Overbys (1993) failure to replicate Chapman and Chapmans (1987a) study. The possible role of task conditions, skilled vs simple, in the emergence of atypical handedness in psychosis-prone college students is discussed.

Czech version of Rey Auditory Verbal Learning test: Normative data

ABSTRACT The present study provides normative data stratified by age for the Rey Auditory Verbal Learning test Czech version (RAVLT) derived from a sample of 306 cognitively normal subjects (20–85 years). Participants met strict inclusion criteria (absence of any active or past neurological or psychiatric disorder) and performed within normal limits on other neuropsychological measures. Our analyses revealed significant relationships between most RAVLT indices and age and education. Normative data are provided not only for basic RAVLT scores, but for the first time also for a variety of derived (gained/lost access, primacy/recency effect) and error scores. The study confirmed a logarithmic character of the learning slope and is consistent with other studies. It enables the clinician to evaluate more precisely subject’s RAVLT memory performance on a vast number of indices and can be viewed as a concrete example of Quantified Process Approach to neuropsychological assessment.

Mixed handedness and schizotypal personality in a non-clinical sample - The role of task demand

Abstract The present study examined the link between schizotypal personality traits and manual hand preference for ‘skilled’ and ‘less skilled’ tasks in a non-clinical sample of college students. The results are consistent with previous findings regarding the higher proportion of non-right handedness among college students who score high on the Schizotypal Personality Questionnaire (SPQ), a self-report measure of schizotypal traits. A significant correlation between hand preference for ‘skilled’ tasks and particular schizotypal traits associated with cognitive—perceptual deficits was noted. The analyses also indicate that unlike schizophrenic patients who exhibit a higher incidence of mixed handedness for ‘less skilled’ tasks (see Nelson, Satz, Green & Cicchetti, 1993), individuals who score high on the SPQ exhibit a higher incidence of non-right handedness for ‘skilled’ tasks. Examination of the stability of non-right handedness over time in this population indicates that at least some of the schizotypes did not maintain their non-right handedness upon retesting, supporting the role of situational variables on lateral dominance in this population.

Analysis of mean learning of normal participants on the Rey Auditory-Verbal Learning Test.

Analysis of the mean performance of 58 groups of normal adults and children on the free-recall trials of the Rey Auditory-Verbal Learning Test shows that the mean auditory-verbal learning of each group is described by the function R1 + Sln(t), where R1 is a measure of the mean immediate memory span, S is the slope of the mean logarithmic learning curve, and ln(t) is the natural logarithm of the trial number t. The analysis also shows that R1 varies with age and other demographic factors, whereas S is almost a constant, and it yields equations for estimating the effect of these factors on R1. Potential use of these findings for assessment of auditory-verbal memory and learning in comparative clinical studies is discussed.