The effect of sensory deprivation and ego strength on a measure of autistic thinking

In an experiment designed to test aspects of the psychoanalytic theory of ego functioning, 18 male and 18 female subjects were assigned in equal numbers to a 3 1/2-hr period of either sensory deprivation (SD), social isolation (SI) or social participation (SP). Their level of autistic thinking was assessed by a word-association measure administered immediately before and immediately after the treatment condition to which each subject had been assigned. Results showed that subjects assigned to SD showed an increase in autistic thinking scores from pretreatment to posttreatment, whereas subjects assigned to the two control conditions (SI and SP) showed a decrease. Although Minnesota Multiphasic Personality Inventory (MMPI) ego strength (Es) scores correlated negatively with the initial level of autistic thinking in all subjects, the experimental and control conditions had their greatest impact on subjects who scored low in Es. Results were interpreted as supporting the hypothesis that consensual functioning (particularly for subjects who scored low on Es) depends on continuing contact with reality.     

Animal psychophysics: improvements in the tracking method.

It is difficult to maintain stimulus control in animal psychophysical studies using the tracking method. Loss of stimulus control is characterized by wandering thresholds and responses in the absence of the stimulus. Rats were trained to make a variable number of licking responses to turn on an auditory stimulus. A response on a lever in the presence of the stimulus was reinforced with food. Two precedures were added to improve stimulus control. First, lever responses in the absence of the stimulus raised the intensity of the stimulus at the next presentation; second, rate of reinforcement in the threshold region was maintained at about the same level as that in the suprathreshold region by reducing the number of licking responses required to turn on the stimulus. Using these two procedures, stimulus control was improved and maintained and reliable auditory intensity thresholds were obtained.     

Sex differences in investigatory and grooming behaviors of laboratory rats (Rattus norvegicus) following exposure to novelty

Prior research suggested that during exposure to novel stimuli, rodent investigation and self-grooming behaviors may be sexually dimorphic and interact with ambient illumination. To test this notion we compared the behavior of adult male and female groups of Long-Evans hooded rats in normal room lighting (860 lx) and in very dim, red light (0.2 lx) following exposure to a novel juvenile conspecific. Illuminance level had little or no effect, but investigatory and subsequent self-grooming behaviors of males were substantially greater than those of females, and females engaged in greater ambulatory activity than did males. In a second experiment adult males and females were exposed to a novel inanimate object. No reliable sex differences were observed. We conclude that social novelty, as provided by exposure to a juvenile conspecific, stimulates greater investigation and postinvestigatory self-grooming than exposure to a novel inanimate object and that exposure to novel conspecifics presents a useful method for the investigation of sex differences, gonadal hormone effects, and interactions of hormones with neurotransmitter systems governing motor control systems.     

The effects of dance team participation on female adolescent physical fitness and self-concept

The purpose of this study was to determine to what extent female physical fitness and self-concept are affected by dance team participation in high school. Eight dancers were tested once prior to and once four months after dance team participation. Eight participants from physical education classes, matched for age, weight, height, grade, and race, were tested once at the same time as the second dance team test. Physiological tests were maximum oxygen uptake, sit-and-reach, one-repetition maximum bench press, skinfolds, and hydrostatic weighing. The self-concept tests were Coopersmith Self-Esteem Inventory, Tennessee Self-Concept Scale, and Body Cathexis Scale. Dependent one-tailed t tests were run to determine differences between dance team pre- and posttests and control and dance team posttests. Dance subjects increased maximum oxygen uptake and one-repetition maximum bench press in addition to improving their body composition as evidenced by a significant decrease in total skinfolds and a near significant decrease in percent body fat. The dance team had a significantly higher maximum oxygen uptake than did controls. No other significant differences were seen between groups. Dance team participants significantly improved physical self and social self on the Tennessee Self-Concept Scale. No other significant differences were seen. A factor that may have affected the self-concept results in this study was low dance team status, due to a combination of unsuccessful previous dance teams and a losing football season. Within the limitations of this study, these results indicate that physical fitness is improved as a result of dance team participation; however, self-concept seems to be affected only minimally, if at all, as compared with participation in physical education classes.     

Control of responding by sounds of different quality: an evolutionary analysis.

Two experiments investigated the acquisition of discriminations between two acoustic stimuli of different quality (noise bursts vs. a 2-kHz pulsed signal) when features of the everyday environment were incorporated into the experiments. In Experiment 1, rats were trained, using food, to press a lever. Throughout all sessions, 5-s trials of noise bursts (the random stimulus) were presented, after variable intertrial intervals, through a remote speaker mounted outside the experimental enclosure. The noise burst occurred randomly with respect to reinforcement of lever pressing and had no programmed relationship to the animal's behavior. When lever pressing was established, the 2-kHz signal was presented through a speaker adjacent to the response lever according to a different set of variable intertrial intervals. A response in the presence of the 2-kHz signal terminated the trial and was reinforced. The 2-kHz signal acquired control of responding within the first few trials, whereas the random stimulus exerted no control of responding. In Experiment 2, rats were trained to press the lever in the presence of the 2-kHz signal presented through the adjacent speaker on a variable intertrial interval. After 14 sessions, 5-s trials of noise bursts (random stimulus) were presented through the remote speaker on the second variable intertrial interval. The random stimulus initially elicited exploratory behavior, which then rapidly declined. Subsequently, the random stimulus exerted no or weak control of responding. The introduction of the random stimulus had no effect on responding in the presence of the adjacent stimulus. In Experiments 3 and 4 the random stimulus was presented through the adjacent speaker, and the stimulus correlated with reinforcement was presented through the remote speaker. In both experiments, there was persistent control of responding by the random stimulus and slow development of control by the stimulus correlated with reinforcement. In Experiment 5, both stimuli were presented through the adjacent speaker. There was persistent control of responding by the random stimulus.     

Acute neuropsychological consequences of coronary artery bypass surgery

This study examines a series of coronary artery bypass patients (CABS) for neuropsychological and regional cerebral blood flow (RCBF) changes at 8 days and 8 weeks post surgery. Seventy-three percent were found to have moderate or severe neuropsychological deficits at 8 days post operation and 37% at 8 weeks post surgery. A comparison group of major vascular and thoracic surgery patients was also found to have a significant proportion of neuropsychological deficit following surgery. The RCBF assessments indicated a significant drop in mean RCBF at 8 days post surgery in the coronary artery bypass group which did not persist to 8 weeks. The comparison group showed no changes in RCBF following surgery. The findings suggest different patterns of recovery and origins of the neuropsychological deficit in the two groups and emphasize the need for appropriate control groups in studies examining the cortical effects of extracorporeal circulation. In addition, the project received generous support from the special trustees of the Middlesex Hospital.     

The component awareness and accuracy of dual- and single-jointed actions

The accuracy with which people execute wrist and elbow movements were measured using three main conditions: (i) single-jointed (wrist or elbow) movements to targets, (ii) dual-jointed (wrist and elbow) movements to targets, and (iii) components of dual-jointed movements to targets, when the task for the subject was to perform the elbow or wrist constituent of the action in isolation, without displacing the second joint. Elbow precision was significantly worse under component than dual conditions, which is compatible with the notion that wrist and elbow activity are conjugately, rather than independently, programmed when a dual-jointed action is performed. The pattern of wrist accuracy was divergent, but possible reasons for this were discussed. In all cases, error was measured in terms of deviation from perfect posture; using this index, the hypothesis that incorporating more moving joints into an action serves to increase movement complexity and jeopardise precision was tested, but the results were ambiguous. Discussion also centered on the problems of using performance data to infer changes in motor programming, and the need for rigorous conceptualisation and research in this area.     

Instrumentation for an electrocutaneous communication device

The device described is a prototype that uses spatiotemporal resolution for electrocutaneous stimulation. Signals initiated through a keyboard activate a matrix of four electrodes that may be applied to the fingers, forearm, abdomen, back, or other parts of the integument. The instrumentation described includes a pulse generator, the active time and delay time controls, the control of the total length of a pulse train, and the constant-current generators whose output is fed into the electrodes. This device may be used as an interface with an alphanumeric device (e.g., a calculator or computer) and as a basic instrument in research investigating the spatial and temporal resolving capacities of the skin senses.