Coherence of early motion signals.

Oscillation thresholds were evaluated for detecting motion and discriminating relative motion. Three horizontally aligned Gaussian blobs oscillated horizontally, with the center in-phase or out-of-phase with the two flankers. Motion thresholds were well below those for static bisection, and involved small contrast changes (<0.25%). Remarkably, acuity was better for discriminating phase relations than for detecting rigid motion, averaging 8.7 and 11.0 arcsec, respectively, for 100 arcmin between blobs. Phase discrimination acuities were robust over separations of 20-320 arcmin and temporal frequencies of 1.5-6 Hz. Motion phase relations must be coherent among spatially separate retinal signals, carrying information about intrinsic image structure.

Migrating foreign body: a new cause of trismus.

A unique case of delayed trismus secondary to an infratemporal foreign body is presented. The pathophysiology and treatment options are discussed.

Factors associated with antidepressant choice.

Previous studies have suggested that nonpsychiatrists tend to prescribe antidepressants (ADs) with the most side effects (SEs), whereas psychiatrists are more likely to prescribe more ADs with fewer SEs. The authors used a questionnaire to examine the antidepressant prescribing pattern, conditions for which ADs were prescribed, and SEs of concern to physicians. Of those surveyed, the psychiatrists reported prescribing significantly more nortriptyline and desipramine, whereas the nonpsychiatrists prescribed more amitriptyline. The nonpsychiatrists were more likely to prescribe ADs for pain, and they were significantly less concerned with orthostatic hypotension. Possible lower dosing and level of concern about orthostatic hypotension may be related. Further study is proposed to assess other factors that might influence AD choice.

A positive view of psychiatrists and psychiatry.

A review of the literature on the personalities, mental health, and professional status of psychiatrists was the basis of a questionnaire designed to assess perceptions of these characteristics by psychiatrists themselves and by their medical colleagues. The 374 physician respondents were divided into two groups, psychiatrists and nonpsychiatrists, and beliefs and perceptions were compared between the two groups and with findings from the research literature. Results revealed some differences in opinion between psychiatrists and nonpsychiatrists, most notably concerning the mental health of psychiatrists. This was also the area in which the literature was least conclusive. Findings indicated, however, that physicians across specialties have a positive overall opinion of psychiatrists and their professional worth, and that psychiatrists see themselves as healthy, effective, and useful practitioners.

Normal cerebral asymmetry in bipolar patients.

Reversal of normal cerebral asymmetry has been reported to be more frequent in children with higher cortical dysfunction and in schizophrenics, in whom it has clinical significance as well. As there are few studies of bipolar patients, we attempted to determine if significant reversal would be found in a clearly diagnosed sample of bipolar patients. As technical differences may account for varying results, we used two previously reported methods and a modified technique. Correlations of computed tomography (CT) findings with neuropsychological variables (Halstead Reitan Battery and WAIS subtests) were also studied. Bipolars and controls did not differ on any CT measure, nor were there meaningful correlations between asymmetry and neuropsychological variables. If if is confirmed that schizophrenics have increased reversed cerebral asymmetry but bipolars do not, it may point to an important difference, as all other CT abnormalities initially described in schizophrenics are now also noted in bipolar patients.

Relative utility of three indices of neuropsychological impairment in a young, chronic schizophrenic population.

The complete Halstead-Reitan Neuropsychological Test Battery and the Wechsler Adult Intelligence Scale were administered to 20 young, male, chronic schizophrenics. Three commonly used indices of neuropsychological impairment were calculated and compared. Although all three indices were similar in separating computerized axial tomography normal from abnormal patients, statistical significance was achieved only with the Halstead Impairment Index. Thus, the easier-to-obtain Halstead Impairment Index appears to be at least as good as, and possibly better than, the more-difficult-to-obtain indices of Percent of Ratings within the Impaired Range and the Average Impairment Rating. Reasons for these findings are discussed.