Semion Kertzman

Go–no-go performance in pathological gamblers

Previous neuropsychological studies demonstrated various deficits of impulse control in pathological gamblers (PGs). However, there are limited data available on response-inhibition impairment among PGs. The present study attempted to assess response inhibition in untreated PGs (N=83), in comparison with normal subjects (N=84). Go/no-go and target-detection conditions of a computerized task were used as a measure of response-inhibition ability. A repeated measures analysis of covariance (ANCOVA-RM) was used with response time, variability of response time, and number of false alarms and misses as dependent measures; group (PG and controls) as the between-subjects measure; condition (target detection or go/no-go) and time slice (first and second in each condition) as repeated measures within-subject factors; and educational level as a covariate. Our results showed that PGs were significantly more impaired in both target detection and go/no-go task performance than controls. The PGs had significantly more false alarms and misses than controls, and they were slower and less consistent in their responses.

Why do young women smoke? III. Attention and impulsivity as neurocognitive predisposing factors

Since nicotine has been shown to facilitate sustained attention and control of impulsivity, impairment in these domains may influence individuals who initiate smoking for various reasons to continue to smoke cigarettes. The purpose of this study was to determine whether young women who smoke regularly but are not abstinent at the time of testing, differ in their cognitive functioning from non-smokers and whether they resemble women who smoked in the past but quit. Female undergraduate students aged 20-30 years were recruited by advertisement from institutes of higher education in the Jerusalem area. The study sample consisted of 91 current smokers (CS), 40 past smokers (PS) and 151 non-smokers (NS). 46 occasional smokers (OS) were also tested. Confounding by withdrawal state was neutralized by including only CS and OS who smoked their last cigarette less than 90 min before testing. Subjects performed a computerized neurocognitive battery, which tests the domains of attention, memory, impulsivity, planning, information processing and motor performance. Analyses were controlled for age. The results showed that CS made significantly more errors than NS on the Continuous Performance Task (CPT), Matching Familiar Figures Test (MFFT) and Tower of London (TOL) test. PS were significantly worse than NS on the MFFT and TOL test. PS did not differ significantly from CS on any test. No association was found between duration of smoking and performance. These findings suggest that a neurocognitive profile characterized by impairments in sustained attention and control of impulsivity may be one of the factors that predispose young women who initiate cigarette smoking to maintain the habit.

Risk-taking decisions in pathological gamblers is not a result of their impaired inhibition ability

This work investigates whether inhibition impairments influence the decision making process in pathological gamblers (PGs). The PG (N=51) subjects performed the Iowa Gambling Task (IGT as the measure of the decision making process) and two tests of inhibition: the Stroop (interference inhibition), and the Go/NoGo (response inhibition), and were compared with demographically matched healthy subjects (N=57). Performance in the IGT block 1 and block 2 did not differ between the groups, but the differences between the PGs and healthy controls began to be significant in block 3, block 4 and block 5. PGs learned the IGT task more slowly than the healthy controls and had non-optimal outcomes (more disadvantageous choices). Impaired IGT performance in PGs was not related to an inhibition ability measured by the Stroop (interference response time) and the Go/NoGo (number of commission errors) parameters. Further controlled studies with neuroimaging techniques may help to clarify the particular brain mechanisms underlying the impaired decision making process in PGs.

Stroop performance in major depression: Selective attention impairment or psychomotor slowness?

BACKGROUND Numerous neuropsychological studies reported impaired Stroop performance in major depressive disorder (MDD) patients. METHODS The present study attempted to identify possible neuropsychological mechanisms involved in this impairment in untreated MDD outpatients (n=75) as compared to healthy subjects (n=83). Inspection Time, Finger Tapping, Simple and Choice Reaction Time were considered as measures of perceptual, motor, psychomotor speed, and response selection, respectively. RESULTS MDD patients performed significantly slower than healthy controls in the neutral and the congruent conditions, but not in the incongruent ones. In order to identify predictors of Stroop performance, linear hierarchical regressions analyses were performed. Age, motor and psychomotor speed were predictors of response time and accuracy on Stroop performance. Significant correlations between response time and the number of errors in all three Stroop conditions were found in MDD patients, while such a correlation was obtained in the healthy controls only in the incongruent condition. LIMITATIONS Although education was included as a covariate in our analyses, suggesting that the observed effects could not be ascribed to education differences, further testing with education-matched samples is warranted. CONCLUSIONS Our study shows that the Stroop task performance is affected by both aging and MDD. Impairment in the Stroop performance can be predicted by psychomotor slowness and by vigilance level in MDD outpatients, but not by impairment of selective attention per se.

Speed-Accuracy Tradeoff in Decision-Making Performance among Pathological Gamblers

Background: Pathological gambling is classified as an impulse control disorder in the DSM-IV-TR; however, few studies have investigated the relationship between gambling behavior and impulsive decision-making in time-non-limited situations. Methods: The subjects performed the Matching Familiar Figures Test (MFFT). The MFFT investigated the reflection-impulsivity dimension in pathological gamblers (n = 82) and demographically matched healthy subjects (n = 82).Results:Our study demonstrated that pathological gamblers had a significantly higher rate of errors than healthy controls (p = 0.01) but were not different in terms of response time (p = 0.49). We found a similar power of correlation between the number of errors and response time in both pathological gamblers and controls. We may conclude that impaired performance of our pathological gamblers as compared to controls in a situation without time limit pressure cannot be explained by a trade-off of greater speed at the cost of less accuracy. Conclusions: The results of our study showed that pathological gamblers tend to make more errors but do not exhibit quicker responses as compared to the control group. Diminished MFFT performance in pathological gamblers as compared to controls supports findings of previous studies which show that pathological gamblers have impaired decision-making. Further controlled studies with a larger sample size which examine MFFT performance in pathological gamblers are necessary to confirm our results.

Neuropsychological mechanisms of Digit Symbol Substitution Test impairment in Asperger Disorder

Our aim was to investigate the neurocognitive mechanisms recruited by adolescents with Asperger Disorder (AD), in comparison to controls, and to detect the underlying mechanisms during the complex information processing required for the performance of the Digit Symbol Substitution Test (DSST). Male adolescents (n=23; mean age 15.1+/-3.6 years) with a DSM-IV diagnosis of AD were compared with a normal male control group with similar demographic characteristics (n=43; mean age: 15.1+/-3.6 years). A computerized neurocognitive battery was administered and included: Inspection Time (IT), Finger Tapping Test (FTT), Simple Reaction Time (SRT), Choice Reaction Time (CRT), Digit Running task (DRT), Stroop test and Digit Symbol Substitution Test (DSST). Adolescents with AD performed significantly worse than controls on the DSST. This impaired DSST performance was related to cognitive mechanisms different from those employed by normal controls. Motor slowness and inability to deal with increased amounts of information affected the performance of the AD group, while shifting of attention was the limiting factor in the controls. Both groups were similarly dependent on response selection. This study demonstrated differences in performance in complex cognitive tasks between adolescents with AD and normal controls that may be related to differences in neurocognitive mechanisms underlying information processing. Future neuroimaging studies are needed to clarify the neural network involved in the differences in cognitive performance between AD subjects and normal controls.

Intrusive trauma recollections is associated with impairment of interference inhibition and psychomotor speed in PTSD

BACKGROUND Intrusive cognitions that enter consciousness involuntarily are prominent symptoms of posttraumatic stress disorder (PTSD). The present study aimed to identify neuropsychological mechanisms involved. METHOD Fifty PTSD outpatients and 50 healthy controls were tested using Finger Tapping, Simple and Choice Reaction Times and Stroop Tasks, to measure motor, psychomotor speed, response selection, and interference inhibition ability respectively. RESULTS PTSD patients performed poorly in all tests, presumably owing to their generalized slowness of information processing and motor reaction. Psychomotor speed was a predictor of slowness and high error rate during the Stroop. Impaired inhibition, as measured by the interference index of the Stroop task, explained 9.7% of the predicated variance in frequency of re-experiencing PTSD symptoms and 23.5% of the predicated variance in augmentation of the interference response time. CONCLUSION Impaired interference control may be related to internal (re-experiencing) and external (sensory) stimuli that leads to cognitive deficits in PTSD patients.

Digit Symbol Substitution test performance: sex differences in a Hebrew-readers' health population.

The Digit Symbol Substitution test is simple to administer and sensitive to individual differences related to cognitive performance. The present study evaluated sex-related differences in performance by a Hebrew reading sample. The test was administered to 275 men and 252 women (age range: 20–44 years). Hebrew women significantly scored higher than the men. Means which increased during four consecutive 30-sec. time periods of performance, was significantly greater for the women than the men. This finding indicates women were more effective on this pair-associated learning task than men.

Can Minnesota Multiphasic Personality Inventory-2 predict response to selective serotonin reuptake inhibitors in depressed outpatients?

There is growing evidence that individual differences among patients with major depressive disorder (MDD) on psychological and demographic measures may predict the therapeutic response to selective serotonin reuptake inhibitors (SSRIs). In this retrospective chart review, 108 outpatients with current major depressive episodes were treated with citalopram, paroxetine, or fluvoxamine. The Hamilton Depression Rating Scale and the Minnesota Multiphasic Personality Inventory-2 were administered before and after 8 weeks of SSRIs treatment. Clinical response was defined as a 50% or greater decrease in the 17-item Hamilton Depression Rating Scale total score (final visit minus baseline). This naturalistic short-term follow-up outcome study demonstrates that among depressive outpatients who responded to an 8-week trial, 57.4% achieved a good response to SSRIs. Statistical analysis showed that SSRI treatment may be 3.03 times more advantageous for MDD outpatients who are younger than 39 years. The patients with an elevated score of above 66T on the Social Introversion Minnesota Multiphasic Personality Inventory-2 scale are approximately 0.37 times as likely to be SSRI responders as are patients with a Social Introversion score less than 66T. Thus, it seems that in MDD outpatient age is the strongest predictor of response to SSRIs.

VARIABILITY OF COLOR CHOICE IN THE LUSCHER COLOR TEST-SEX DIFFERENCES '

In this preliminary investigation of variability of responses on the Lüscher Color Test, subjects were 567 volunteers administered the test twice with a 10-min. interval between them. Two hypotheses were tested: (a) that variability of responses attests to the personality of the respondent (tested by the relations of variability and MMPI scale scores), and (b) variability of responses is based on learning the tests content. As such, mens scores should be more variable than womens. Analysis showed that variability was not correlated with scores for personality on the MMPI scales. Mens scores are more variable than womens, but only until age 45.