Quantitative and qualitative analyses of clock drawings in Alzheimer's and Huntington's disease.

Although visuoconstructive impairment has been reported in both Alzheimer's (DAT) and Huntington's (HD) disease, there is little knowledge concerning how this cognitive deficit differs quantitatively and qualitatively in these two progressive dementias. To address this issue, the present study compared performances on the Clock Drawing Test (CDT: command and copy) of 25 DAT patients, 25 equally demented HD patients, and 25 elderly normal controls (NC). In the command condition, both patients groups were significantly impaired compared to the NC group. Although there was no significant difference between DAT and HD patients' total quantitative scores, a qualitative error analysis revealed a number of dissociations between the two patient groups. Graphic difficulties, very common in HD patients, were virtually absent in DAT patients; in contrast, conceptual errors were almost exclusively seen in DAT patients and were related to the severity of their dementia. Perseveration and "stimulus-bound" responses were also more frequent in DAT patients, and both groups made visuospatial errors. In the copy condition, the DAT, but not the HD, patients evidenced a marked improvement in performance. These results indicate that while both DAT and HD patients have significant visuoconstructive difficulties even in the early stages of their disorders, the specific cognitive processes underlying their quantitative impairments are quite different. It is possible that the DAT patients' conceptual errors are yet another indicator of the deterioration of their semantic knowledge.     

Conditioned suppression of proboscis extension in Drosophila melanogaster

Food-deprived Drosophila melanogaster extend their proboscises following sucrose stimulation of the front tarsi (the proboscis extension reflex). Médioni and Vaysse (1975) reported that the inhibition of this response can be conditioned over trials if such proboscis extensions are punished by applying an aversive stimulus to the foreleg tarsi. In this study, Médioni and Vaysse's basic observations of conditioning were replicated, with a different strain of flies and a modified conditioning apparatus.     

Dynamic operations of thought systems

Our research program focuses on thought systems consisting of a core event that might befall a person and other topics evoked in free associating on this event, mostly its salient antecedents and consequences. We theorize that the pattern of salient antecedents and consequences evoked by the core event are related to its judged desirability and likelihood by several adaptive principles, such that when a change is directly induced in one part of the belief system it produces predictable remote adjustments in other parts. In a first experiment we manipulated the core event's judged desirability or likelihood and tested for predicted remote effects on the salience of antecedents and consequences. A second experiment conversely manipulated the salience of antecedents or consequences and tested for predicted remote effects on the core event's judged desirability and likelihood.     

Prevalence of traumatic brain injury in an inpatient psychiatric population

This study investigated the prevalence of traumatic brain injury (TBI) in an inpatient psychiatric population. We hypothesized increased prevalence of TBI relative to the general population due to a variety of risk factors observed in psychiatric patients. One hundred (mean age = 34) psychiatric inpatients completed the revised Head Injury Questionnaire. Chart review of 17 subjects reporting injuries established whether injuries were documented in medical records. Sixty-eight percent of this psychiatric population reported one or more injuries in which they were unconscious or dazed. This number is higher than the prevalence in the general population. Injuries were generally of mild to moderate severity; multiple injuries were common. Chart review of 17 subjects reporting TBI indicated that histories of TBI had not been noted in the medical record. Finally, 63% of TBI subjects reported that their injury predated the onset of their psychiatric symptoms. These results suggest a possible role of TBI in psychiatric symptomatology and have implications for psychiatric treatment in this population.     

A critique of Plomin and Foch's "A Twin Study of Objectively Assessed Personality in Childhood"

Plomin and Foch's (1980) study of objectively assessed personality in childhood is critiqued on five points: (a) conceptual validity of the measures, (b) stability of the measures for the population age range, (c) comparability of populations, (d) accuracy of literature review, and (e) appropriate interpretation of broad heritability data. The Plomin and Foch study contains major errors; it is theoretically and methodologically flawed. Their report is especially significant because it is representative of problems critical to the study of the genetic correlates of personality.     

Effects of household sex composition on the salience of one's gender in the spontaneous self-concept

It was hypothesized that being a boy or a girl becomes more salient in a child's self-concept to the extent the other sex numerically predominates in the child's household. This prediction was based upon an information-processing, distinctiveness postulate that a person contemplating a complex stimulus (such as the self) selectively notices and encodes its more distinctive, information-rich aspects. The spontaneous self-concept elicited by nondirective “Tell us about yourself” interviews of 560 school children were scored for spontaneous mention of one's gender. As predicted, boys spontaneously mentioned their maleness more often when they came from households where females were in the majority; girls mentioned their femaleness more often when from households with male majorities; boys mentioned their maleness more often when from father-absent than from father-present homes. Incidental findings are that gender is more salient in the negation self-concept (“Tell us what you are not”) than in the affirmation self-concept (“Tell us about yourself”) especially for girls and that gender becomes increasingly salient as the child grows older.     

Historical comparisons: Testing psychological hypotheses with cross-era data (1)

Cross-era research, an approach which involves developing and testing social science hypotheses in terms of historical time-series data, is first discussed as regards its relationship to other comparative research approaches. Some examples of cross-era research in psychology are described. Special problems that arise in cross-era research, and proposed methods of coping with them, are discussed as regards each of the three successive phases of research: creative hypothesis formation problems; difficulties that arise in the hypothesis-testing phase; and problems that emerge during the phase of communicating and utilizing the findings.