Timing dysfunctions in schizophrenia as measured by a repetitive finger tapping task

Schizophrenia may be associated with a fundamental disturbance in the temporal coordination of information processing in the brain, leading to classic symptoms of schizophrenia such as thought disorder and disorganized and contextually inappropriate behavior. Although a variety of behavioral studies have provided strong evidence for perceptual timing deficits in schizophrenia, no study to date has directly examined overt temporal performance in schizophrenia using a task that differentially engages perceptual and motor-based timing processes. The present study aimed to isolate perceptual and motor-based temporal performance in individuals diagnosed with schizophrenia using a repetitive finger-tapping task that has previously been shown to differentially engage brain regions associated with perceptual and motor-related timing behavior. Thirty-two individuals with schizophrenia and 31 non-psychiatric control participants completed the repetitive finger-tapping task, which required participants to first tap in time with computer-generated tones separated by a fixed intertone interval (tone-paced tapping), after which the tones were discontinued and participants were required to continue tapping at the established pace (self-paced tapping). Participants with schizophrenia displayed significantly faster tapping rates for both tone- and self-paced portions of the task compared to the non-psychiatric group. Individuals diagnosed with schizophrenia also displayed greater tapping variability during both tone- and self-paced portions of the task. The application of a mathematical timing model further indicated that group differences were primarily attributable to increased timing – as opposed to task implementation – difficulties in the schizophrenia group, which is noteworthy given the broad range of impairments typically associated with the disorder. These findings support the contention that schizophrenia is associated with a broad range of timing difficulties, including those associated with time perception as well as time production.     

Cognitive, Dispositional, and Psychophysiological Correlates of Dependent Slot Machine Gambling in Young People

In Study 1, young dependent and nondependent slot machine gamblers were interviewed, assessed for locus of control and administered the Eysenck Personality Questionnaire. Dependent gamblers were revealed as reliably more internal in terms of locus of control than their nondependent counterparts, and, in the interview, were much more likely to affirm that they could exercise control over the slot machines they played. Dependent gamblers registered higher psychoticism scores than both the nondependent gamblers and appropriate age-group norms. Their high psychoticism scores resonated well with interview revelations that boredom mitigation frequent underlay dependent gambling.
In Study 2, blood pressure was monitored in dependent and nondependent gamblers at rest and before, during and after slot machine play. Subjects were given £5 for this purpose and the time it took them to use up this money was recorded, as was the extent of any returns they received. They were also asked how much they expected to recoup. The £5 lasted a similar amount of time for the two groups, and they managed similar rates of return on their stake. However, the dependent gamblers expected to win more than the nondependent gamblers and their estimates of returns exceeded what they actually recouped. Slot machine play was associated with an increase in blood pressure, and while groups did not differ in terms of the magnitude of the rise provoked, there was a general trend for dependent gamblers to show lower basal levels of cardiovascular activity, although this was statistically reliable only in the case of diastolic blood pressure.     

Evolution of the African American Family Personality: Considerations for Family Therapy

Both internal and external factors help to determine the personality of the African American family. Personality traits of the African American family include adherence to historical values, diversity in family structure, and family communication. A review of the history of the African American family from its African roots to contemporary America is presented here.     

The estimation of ultrametric and path length trees from rectangular proximity data

A least-squares algorithm for fitting ultrametric and path length or additive trees to two-way, two-mode proximity data is presented. The algorithm utilizes a penalty function to enforce the ultrametric inequality generalized for asymmetric, and generally rectangular (rather than square) proximity matrices in estimating an ultrametric tree. This stage is used in an alternating least-squares fashion with closed-form formulas for estimating path length constants for deriving path length trees. The algorithm is evaluated via two Monte Carlo studies. Examples of fitting ultrametric and path length trees are presented.G. De Soete is Aspirant of the Belgian Nationaal Fonds voor Wetenschappelijk Onderzoek at the University of Ghent, Belgium. W. S. DeSarbo and J. D. Carroll are Members of Technical Staff at AT&T Bell Laboratories, Murray Hill, N.J. G. W. Furnas is Member of Technical Staff at Bell Communications Research, Murray Hill, N.J.     

Androgen administration to hypogonadal and eugonadal men—effects on measures of sensation seeking,personality and spatial ability

A group of hypogonadal and a group of eugonadal (endocrinologically normal) men complaining of sexual dysfunction were treated with androgens. Psychometric measures of sensation seeking, personality and spatial ability were made before and after treatment. Short-term androgen administration had little effect on these measures. However when the two patient groups were compared while receiving no androgen treatment, the eugonadal men produced significantly higher scores on the Sensation Seeking Scale.