A comparison of clinical features in trichotillomania and obsessive-compulsive disorder.

Trichotillomania (TM) recently has been conceptualized as a variant of obsessive-compulsive disorder (OCD). However, no systematic data have compared the clinical features of these two disorders. Here we report data from 8 TM and 13 OCD patients which suggest important clinical differences between groups. First, TM patients reported a significantly greater degree of pleasure during hair-pulling than OCD patients reported during performance of ritualistic behaviors. Second, TM was accompanied by significantly fewer associated obsessive-compulsive symptoms. Third, the groups differed with regard to other clinical features including anxiety, depression, and personality characteristics. We conclude that TM is not conceptualized best as a variant of OCD.     

Correlates of memory decline: a 4-year longitudinal study of older adults with memory complaints.

Change in memory performance and its correspondence to change in speed of performance and self-reported memory functioning were investigated longitudinally in 30 older adults with memory complaints. Subjects were assessed by self-report questionnaires and cognitive tests 3 times, at near 2-year intervals. A significant decline in word-recall scores was found, which was accompanied at the group level by significant self-reported decline in everyday memory functioning and nonsignificant decline in Wechsler Adult Intelligence Scale Digit Symbol scores (alpha = .05). The oldest subjects showed the most substantial declines in memory performance. At the individual level, however, memory change did not significantly correlate with either change in self-reports or change in Digit Symbol scores. Although these results do not support a cognitive slowing model of decline at the intraindividual level, they do have implications for intervention of age-related memory decline.     

Problems with the slosson intelligence test for preschool children

The Slosson Intelligence Test (SIT) was administered to 92 preschool children. Because of the considerably above average performance of the group on the SIT, the Stanford-Binet Intelligence Scale was administered to a sample of the group and the results compared to the results on the SIT. The differences between the two sets of scores was highly significant, and as a result the SIT appears to over estimate the performance of average preschool children.     

Automatic phonological priming in visual word recognition

Theories of visual word recognition have proposed that a word’s phonological properties can be involved in reading visually presented words. Further, it is commonly supposed that this phonological information can be arrived at in at least two ways: (1) by looking it up after identifying the word visually (a lexical route) or (2) by rule-governed translating of the word’s orthographic code (a nonlexical route), Four experiments were conducted to examine whether phonological information is automatically accessed in visual word recognition, and, if so, how this occurs. A priming technique was used with a display sequence of mask, prime, target, mask. Subjects were asked to make written responses to any words that they thought were present, and prime identification was minimal. A facilitatory effect of phonological priming on target identification occurred when primes were homophones of targets. However, no similar facilitation occurred when the prime was a nonword homophone of the target. Further, the homophone priming effect was found irrespective of whether targets followed the spelling-to-sound rules of English. The results suggest that automatic access to phonology can occur in visual word recognition and that it operates by means of a lexical route.     

Sensitivity to reinforcement in concurrent arithmetic and exponential schedules

The generalized matching law states that the logarithm of the ratio of responses emitted or time spent responding in concurrent variable-interval schedules is a linear function of the logarithm of the ratio of reinforcements obtained. The slope of this relation, sensitivity to reinforcement, varies about 1.0 but has been shown to be different when obtained in different laboratories. The present paper analyzed the results from 18 experiments on concurrent variable-interval schedule performance and showed that response-allocation sensitivity to reinforcement was significantly smaller when arithmetic, rather than exponential, progressions were used to produce variable-interval schedules. There were no differences in time-allocation sensitivity between the two methods of constructing variable-interval schedules. Since the two laboratories have consistently used different methods for constructing variable-interval schedules, the differences in obtained sensitivities to reinforcement are explained. The reanalysis suggests that animals may be sensitive to differences in the distribution of reinforcements in time.     

Sex differences in spatial ability and spatial activities

Explanations of sex-related differences in spatial ability emphasizing the role of sex-differentiated experience have not been supported by direct measurement of spatial activities during adolescence, the period when these differences seem to increase. The present research involved development of a scale to measure the spatial experience of adolescents and adults. In Study 1, a list, as complete as possible of adolescent activities was compiled and given to undergraduate judges for ratings of involvement of spatial skills and sex-typing. Judges also indicated whether they had participated in each activity. Activities considered spatial by 75% or more of the judges were used to develop a spatial experience questionnaire. Judgments of the spatial nature of tasks were positively correlated with judged masculinity and with greater male than female participation. In Study 2, participation in spatial activities by undergraduates was correlated with spatial ability as measured by the Differential Aptitude Test. The activity questionnaire should prove useful in studying the development of spatial ability in adolescents and adults.