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Zeev Ben Nahum

Publications and source records attributed to Zeev Ben Nahum.

2 recordsLinked to original sources

Stroop performance in pathological gamblers.

Pathological gambling is a relatively prevalent psychiatric disorder that typically leads to severe family, social, legal, and occupational problems and is associated with a high rate of suicide attempts. Understanding the neurobiological basis of pathological gambling is a current focus of research, and emerging data have demonstrated that pathological gamblers may have impaired decision-making because of an inability to inhibit irrelevant information. In this study, we examined pathological gamblers by using the Stroop Color-Word Test, a neurocognitive task used to assess interference control. The "reverse" variant of the Stroop Color-Word Test was administered to a cohort of medication-free pathological gamblers (n=62) and a cohort of age-matched controls (n=83). In the reverse variant of the Stroop task, subjects are asked to read the meaning of the word rather than name the ink color. The reverse Stroop task was chosen because it highly discriminates ability to inhibit interference in a population of psychiatric patients. In our study, performance on the reverse Stroop task in the pathological gamblers was significantly slower and less accurate than in the healthy subjects. A new finding in our study was that for pathological gamblers, the average reaction time in the neutral condition (where the color names are displayed in black letters) was slower than the average reaction time in the incongruent condition (where the meaning of the color name and the color of the printed letters are different). This controlled study extends previous findings by showing that performance on the Stroop task is impaired in a sample of medication-free pathological gamblers.

Adult↗

Simple real-time computerized tasks for detection of malingering among murderers with schizophrenia.

It is our contention that computer-based two-alternative forced choice techniques can be useful tools for the detection of patients with schizophrenia who feign acute psychotic symptoms and cognitive impairment as opposed to patients with schizophrenia with a true active psychosis. In our experiment, Visual Simple and Choice Reaction Time tasks were used. Reaction time in milliseconds was recorded and accuracy rate was obtained for all subjects' responses. Both types of task were administered to 27 patients with schizophrenia suspected of having committed murder. Patients with schizophrenia who were clinically assessed as malingerers achieved significantly fewer correct results, were significantly slower and less consistent in their reaction time. Congruence of performance between the Simple and Choice tasks was an additional parameter for the accurate diagnosis of malingering. The four parameters of both tests (accuracy of response, reaction time, standard deviation of reaction time and task congruency) are simple and constitute a user-friendly means for the detection of malingering in forensic practice. Another advantage of this procedure is that the software automatically measures and evaluates all the parameters.

Adult↗