Suggestiveness in photospread line-ups: Similarity induces distinctiveness

The present research examined whether line-ups based on target (‘suspect’) face similarity are biased or suggestive. Four experiments are described in which subjects constructed photographic line-ups by selecting foils similar in appearance to a target. Later, another group of subjects who had not seen the faces before (mock witnesses) were asked to pick out the targets from the line-ups. All four experiments showed that mock witnesses selected the target significantly more often than expected by chance, thereby demonstrating suggestiveness. Three alternative line-up construction methods were also evaluated. In these methods, foil selection was based not only on target similarity but also on similarity with one or more of the other line-up faces. Results showed that alternative line-up targets were not selected significantly more often than chance, suggesting that bias was reduced. An overall analysis showed that the alternative line-ups were significantly less suggestive than target-based line-ups. The results indicate that foil selection procedures that incorporate foil-to-foil similarity produce fairer line-ups than those exclusively based on target similarity.     

Relationship between religion-related factors and obsessive compulsive disorder

This exploratory study sought to determine whether selected religion-related factors differentiated between 86 patients with obsessive compulsive disorder (OCD), 73 patients with panic disorder, and 292 patients with other psychiatric (non-anxiety) disorders. A standard history questionnaire was used to obtain information from patients concerning religion of origin, involvement in religious activities, religious conflict, and perceived religiousness of parents. It was found that the percentage of patients who reported experiencing religious conflict was significantly higher for the OCD group than for the other two groups. Other findings suggested associations between Catholicism and OCD and between Protestantism and panic disorder, but further research is needed to clarify these relationships. This article is based on a paper presented at the 98th annual convention of the American Psychological Association, Boston, August 1990.     

Is anorexia nervosa a neuropsychological disease?

Evidence for central nervous system, and more particularly cortical, etiology of anorexia nervosa is reviewed. Topics covered are neuropsychiatric comorbidity, inheritance patterns, the neurobiology of body-image disturbance and of the eating function, perinatal and alcoholic insult to the brain, neurochemical and neuroelectric disturbance, anatomic and metabolic brain imaging, and neuropsychological impairment. It is concluded that there is indeed an important neuropsychological etiological dimension to anorexia nervosa. The profile most frequently associated with anorexia nervosa is right posterior hypometabolism, followed by right anterior hypermetabolism, both associated with right-sided abnormal electroencephalogram spiking. It is also proposed that bulimia consists of a positive neurological subtype and that restricting anorexia represents a negative neurological subtype. Priorities for further research into anorexia nervosa are specified to include twin adoption studies, brain electrical topography studies, postmortem histological studies, and experimentally inspired neuropsychological studies.     

Cocaine-induced brainstem seizures and behavior.

A variety of abnormal sensory/motor behaviors associated with electrical discharges recorded from the bilateral brainstem were induced in adult WKY rats by mechanical (electrode implants) and DC electrical current stimulations and by acute and chronic administration of cocaine. The electrode implant implicated one side or the other of the reticular system of the brainstem but subjects were not incapacitated by the stimulations. Cocaine (40 mg/kg) was injected subcutaneously for an acute experiment and subsequent 20 mg/kg doses twice daily for 3 days in a chronic study. Cocaine generated more abnormal behaviors in the brainstem perturbation group, especially the electrically perturbated subjects. The abnormal behaviors were yawning, retrocollis, hyperactivity, hypersensitivity, "beating drum" behavior, squealing, head bobbing, circling, sniffing, abnormal posturing, and facial twitching. Shifts in the power frequency spectra of the discharge patterns were noted between quiet and pacing behavioral states. Hypersensitivity to various auditory, tactile, and visual stimulation was present and shifts in the brainstem ambient power spectral frequency occurred in response to tactile stimulation. These findings suggest that the brainstem generates and propagates pathological discharges that can be elicited by mechanical and DC electrical perturbation. Cocaine was found to activate the discharge system and thus induce abnormal behaviors that are generated at the discharge site and at distant sites to which the discharge propagates. Cognitive functions may also be involved since dopaminergic and serotonergic cellular elements at the brainstem level are also implicated.