Circadian factors during sustained performance: Background and methodology

Cornell University Medical College, Westchester Division, The New York Hospital, White Plains, New York It is well established that there is a complex timekeeping mechanism in the human brain. This mechanism is associated with a variety of physiological and psychological rhythms having a period of about a day, and thus referred to as circadian rhythms. The circadian system has recently been modeled in terms of two underlying oscillators, one much more resistant to changes in routine than the other. These oscillators are considered to be endogenous, that is, internal to the organism, and not reliant for their existence upon changes in the person’s environment or general behavior. They thus continue to run even when the sleep/wake cycle is suspended, as in sustained operations. Thus, by their very nature, sustained operations require the individual to override the inputs that are coming from his or her circadian system (especially the indication that sleep is required). The aim of this paper is to provide a background to the area of circadian rhythms research, including a section on the methodology, so that the impact of the circadian system on sustained operations can be better understood.     

Predictability,controllability, and inoculation against learned helplessness

Nondepressed human subjects were divided into seven groups. On a series of discrimination problems, a helplessness group received insoluble problems, a solvable group received contingent feedback, and a no treatment control group received no feedback. For two other groups insoluble problems were preceded by success feedback on a different task presented according to a fixed ratio (FR) or variable ratio (VR) schedule of reinforcement. Two control groups received either FR or VR schedules of success but were not examined on the discrimination problems. All groups were tested for escape/avoidance performance on a human shuttle box. Both FR and VR schedules produced an inoculation against learned helplessness; escape performance by the helplessness group was significantly worse than that of FR and VR inoculation groups. These latter groups performed similar to the solvable and three control groups. Significantly worse than that of FR and VR inoculation groups. These latter groups performed similar to the solvable and three control groups. Significantly fewer subjects in the VR inoculation group exhibited avoidance responses than their counterparts in the FR inoculation group. despite similar escape performance. The findings indicate that learned helplessness can be prevented in humans and suggest different sources of interference produced by unpredictable and uncontrollable events.     

An alternative perspective on sex differences in organizational settings: The process of legitimation

This article takes a sociological approach to a problem that has usually been considered as a psychological phenomenon. It addresses the problem of male—female interactions in work situations utilizing the organizational concepts of division of labor and legitimacy. Traditional explanations evoking sex-role socialization are reviewed and rejected for purposes of experimentation and intervention. An alternative argument, focusing on the structural arrangements of organizational settings, is presented as an explanation for behavioral effects previously attributed to inherent sex differences. The results of a pilot study are briefly described, and directions for further experimentation and possible intervention strategies are suggested.The bibliographic search and initial conceptualization of this research was supported by a grant from the Ford Foundation under the auspices of the Center for Research on Women at Stanford University. We are grateful to Miriam Rosen for much of the bibliographic work. The pilot study was supported in part by funds from the Guggenheim Foundation and by a grant from the Spencer Foundation. We also wish to thank Richard Torres and Christie Timberlake for their invaluable assistance on this project.     

Mental rotation and the frame of reference in blind and sighted individuals

Mental rotation in the congenitally blind was investigated with a haptic letter-judgment task. Blind subjects and blindfolded, sighted subjects were presented a letter in some orientation between 0° to 300° from upright and timed while they judged whether it was a normal or mirror-image letter. Both groups showed an increasing response time with the stimulus’s departure from upright; this result was interpreted as reflecting the process of mental rotation. The results for the blind subjects suggest that mental rotation can operate on a spatial representation that does not have any specifically visual components. Further research showed that for the sighted subjects in the haptic task, the orientation of a letter is coded with respect to the position of the hand. Sighted subjects may code the orientation of the letter and then translate this code into a visual representation, or they may use a spatial representation that is not specifically visual.     

Effects of erotic stimuli on sexually functional and dysfunctional women: Multiple measures before and after sex therapy

A group of 11 women entering sex therapy for treatment of low arousal, and a comparison group of 11 women experiencing no arousal deficit, viewed an erotic film, listened to an erotic audiotape, and engaged in sexual fantasy during two experimental sessions. Session I occurred pre-treatment for the low arousal group. Session II occurred post-treatment. The adequate arousal group was tested at comparable points in time. Sexual arousal was measured subjectively by self-rating and physiologically by a vaginal photoplethysmograph. Contrary to expectation, the two groups showed equivalent significant increases in physiological response during the erotic stimuli in both sessions. However, the adequate arousal group rated subjective arousal significantly higher than the low arousal group in Session I, while no difference was found between the groups in Session II. Significant correlations were present between physiological response and ratings of several affective reactions to the audiotape, though few significant correlations were found between physiological and subjective sexual arousal measures. These data indicate a discrepancy between genital responses and ratings of sexual arousal for which several interpretations are offered.     

APPLICATION OF A SOCIAL SKILLS TRAINING PROGRAM IN THE MODIFICATION OF INTERPERSONAL DEFICITS AMONG RETARDED ADULTS: A CLINICAL REPLICATION

Six mentally retarded adults, equally divided into two treatment groups, were provided with individualized social skills training programs. Treatment, evaluated via a multiple-baseline design strategy, was sequentially and cumulatively applied across target behaviors over a four-week intervention period. Behavioral observation probes and social validation measures served as the primary dependent variables. Results indicated that (a) treatment was effective for virtually all behaviors across all subjects, (b) improvements occurred for both training and generalization scenes, and (c) behavioral performance was maintained one month following the termination of treatment.     

Experimental assessment of tinnitus aurium

A 32-year-old male volunteer with an eight year history of chronic unilateral tinnitus (ear-ringing) participated in a behavioral assessment strategy that included a series of measurement and modification procedures. A psychophysical matching technique was employed throughout a planned combination of procedures to assess and manipulate the intensity or loudness of tinnitus responses. Following baseline assessment, measurements were conducted at varying times of the day, concomitant with exposure to music, during progressive relaxation training, and under conditions of caffeine consumption. The value of careful assessment to describe cues and conditions associated with tinnitus and its reduction are discussed with implications for behavior treatment design and evaluation.     

Mimicry versus imitative modeling: Facilitating sentence production in the speech of the retarded

Two methods of language instruction administered to mentally retarded subjects at the two-word stage of language development were investigated. Subjects of the mimicry training group imitated Agent-Action-Object (AAO) constructions immediately after presentation, while subjects of the imitative modeling group first heard the AAO presentation and later produced the AAO construction in response to a verb question. Imitative modeling subjects achieved as many correct AAO responses during training and more correct responses on a generalization task and in a free play setting. They also displayed more novel response behavior (selective imitations) and spontaneously corrected productions. The results support the use of modeling procedures for inducing language production in the retarded.