Effects of alcohol and extended practice on divided-attention performance

The effects of alcohol and extended practice on divided attention were investigated using a visual tracking task and an auditory detection task. Subjects performed the tasks with and without alcohol, under single-task (S) and dual-task (D) conditions, both before and after they had received extended practice under single-task conditions without alcohol. Tracking accuracy improved with practice and was impaired under divided-attention conditions but was not affected by alcohol. Speed of detection was impaired by alcohol, improved by practice, and impaired by divided attention. Extended practice did not reduce the influence of alcohol. The effects of both alcohol and practice on speed of detection were significantly greater under dual-task conditions than under single-task conditions. Analysis of detection-task reaction times in terms of relative divided-attention costs, (D-S)/S, showed no effect of alcohol, but a highly significant reduction in costs with extended practice. It is concluded that (1) alcohol and practice can have quantitatively, but not qualitatively, similar effects on speeded performance, and (2) the effect of alcohol is not influenced by the attentional requirements of the task.     

Cross-gender perceptions of facial attributes and their relation to attractiveness: do we see them differently than they see us?

Examination of perceptions of human facial attributes revealed that individual attributes are similarly perceived by males and females. However, patterns of attribute interrelationships differ as a function of gender of the face. Undergraduate students (N = 280) rated pictures of 40 male or female Caucasians on 12 physical attributes (e.g., nose size, face width) and overall attractiveness. The four sets of attribute ratings (defined by rater gender and picture gender) were submitted to principal components analyses, and five-factor solutions were found for each condition (accounting for about 76% of the variance). Comparisons of the four component solutions using confirmatory factor procedures revealed that male and female raters share one factor structure when rating photographs of female faces and another factor structure when rating photographs of male faces. Multiple regression analyses revealed that the patterns of attribute interrelationships were not "perceptual units" in the perception of attractiveness, and that different "rules" are used to assess the attractiveness of male and female stimuli faces. The importance of these results for models of facial attractiveness and interfacial similarity judgements are discussed.     

How much processing do nonattended stimuli receive? Apparently very little, but...

The early versus late selection issue in attention models was examined by means of a new methodology. Through cues or precues, attention was directed to one location of a multistimulus visual display and, while attention was so engaged, the identity of a stimulus located at a different position in the display was changed. By varying the time after display onset before the stimulus was changed, we controlled the preview time that the original stimulus was represented on the retina. Then, using a marker cue, we directed the subject's attention to the location of the changed stimulus. The subject's response was a timed discrimination between two possible target letters. The data of main interest was the effect of preview time upon the subject's latency in identifying the new target that appeared in the changed location. We found that the preview time of the original stimulus, before RT was affected to the new target, depended upon whether the original stimulus was a neutral (noise) letter or whether it was the alternative target. When the original stimulus was a noise letter, RTs to the new target were just as fast as those obtained in the control condition in which the target was present throughout the preview interval and did not change its identity. Significant effects upon RT were obtained at preview times of 83 msec when the original stimulus was one of the targets that changed to the alternative target. Preview times also varied as a function of precuing. Preview times were correspondingly shortened when the first cue occurred 50 msec before display onset, thus providing an extra 50 msec for attention to be directed to the first display location. The results were interpreted in terms of two separate information-processing systems in the human: an automatic system and an attentional system. Even though a stimulus may have been automatically processed, when the attention system is directed to that stimulus, processing starts at the beginning again.     

Information-processing differences and laterality of students from different colleges and disciplines

1023 college students were assessed for hemispheric brain dominance using the paper-and-pencil test, the Human Information Processing Survey. Analysis of scores of students majoring in Advertising, Interior Design, Music, Journalism, Art, Oral Communication, and Architecture suggested a preference for right-brain hemispheric processing, while scores of students majoring in Accounting, Management, Finance, Computer Science, Mathematics, Nursing, Funeral Service, Criminal Justice, and Elementary Education suggested a preference for left-hemispheric strategies for processing information. The differential effects of hemispheric processing in an educational system emphasizing the left-hemispheric activities of structured logic and sequential processing suggests repression of the intellectual development of those students who may be genetically favorable to right-hemispheric processing.     

Effect of visuomotor rehearsal with videotaped modeling on racquetball performance of beginning players

This investigation was designed to assess the effect of visuomotor behavior rehearsal (VMBR) with videotaped modeling on racquetball performance of beginning players. 24 male students in beginning racquetball class were randomly assigned to either VMBR with videotape modeling or relaxation and imagery (no modeling) condition for a 2-wk. training period. All subjects were pre- and posttested on forehand and backhand racquetball skill tests. Analysis indicated an effect for forehand shooting, with those given visuomotor behavior rehearsal with videotaped model exhibiting better performance than the relaxation and imagery group, but no effect for backhand shooting.     

Reaction time and index of difficulty in target-striking tasks with changes in direction

Reaction time (RT) for two three-segment target-striking responses involving changes in direction of movement was studied as a function of differences in their additive index . . . index of difficulty (A-ID). In one condition the A-ID was 9.96 and in the other, 6.76. For 16 right-handed university students, mean RT was significantly faster for the condition in which the index was 6.76. Movement times were consistent with Fitts' Law. The data support Sidaway, Christina, and Shea's 1988 prediction that for target-striking movements with changes of direction, RT is a function of the cumulative series of movement constraints.     

Insulin and dextrose effects on fixed-interval behavioral thermoregulation in albino rats

This study is a systematic replication of the effects of insulin doses on operant behavior reinforced (in an earlier study) by fixed-ratio schedules of microwave (MW) reinforcement. In this study, insulin and dextrose doses were administered (ip) prior to fixed-interval 2-min. schedules of MW reinforcement in rats tested in a cold environment. Six Sprague-Dawley rats were conditioned to regulate their thermal environment with 5-sec. exposures of MW radiation (SAR = 0.34 Watts/kg/(mW/cm2) under the FI-2' schedules. Humulin-regular insulin and 50% solutions of dextrose were administered (ip) alternately with saline control sessions for 8-hr. durations. A within-subjects, repeated-measures 4 x 8 x 3 factorial analysis of variance design showed that insulin doses suppressed operant responding for heat, which confirmed the results of the earlier study under a different schedule. In addition, high doses of dextrose had similar suppressing effects on operant responding for heat. The data are interpreted in terms of the discriminative properties of increased thermogenesis produced by the insulin and dextrose doses. The suppressing effects were more pronounced for the first two hours, yet they persisted for approximately six hours of the 8-hr. sessions.     

EEG performance spectral mapping during drug therapy in a patient with schizophrenic psychosis

In a paranoid-hallucinatoric patient with chronic course and acute exacerbation a EEG mapping study during neuroleptic treatment was carried out. The typical changes of the alpha power spectra in schizophrenic psychoses as well the normalization after neuroleptic treatment could be found in the alpha map. The changes were in correlation to the clinical state.     

Psychoses in epilepsy

The heterogenous psychoses in epilepsies, caused by well known conditions, are not rare but associated with regularly a few of seizure-types not with the nature and development of attacks. Polar transitional ranks and converging courses of schizophrenic (accentuated) syndromes in epilepsies and idiopathic schizophrenias are rather frequent. Also (sub-)acute schizophrenic psychoses are corresponding to the complete palette of first and second rank symptoms (K. Schneider) of idiopathic schizophrenias. After manifestations of epilepsy these syndromes can appear at any time. It is given a profile of risks. Progressive avoidance of a. phenylaceturea, b. mixtures of antiepileptics did not put an end to psychotic syndromes: Long-term therapies with 1. Polytherapy, 2. Primidone and Phenytoin (dosedependant) as well as 3. Ethosuximide (-monotherapy) cause a disorder of feed back mechanisms, especially a disturbed regulation of vigilance and sleeping-waking-cycle and their psychological correlates. Carbamazepine and Sodium Valproate are, plasma-level-controlled of preventive antipsychotic effect. Selected neuroleptics of rather slight epileptogenic potency are of going down importance. Benzodiazepines are required mostly in prepsychotic syndromes, Lithium compounds in selected cases. There is no more alternative seizures or psychosis.