Tamir Caspy

Acute and repeated gestational stress affect offspring learning and activity in rats

This study assessed possible long-lasting effects of mild, indirect prenatal stress upon offspring. Dams were restrained for 30 minutes either once or four times during the third trimester of gestation. Their male offspring were challenged in adulthood with a series of appetitive operant learning tasks. Both acute and repeated prenatal maternal restraint retarded the performance of the offspring in a selective manner: deficits appeared during the reversal stage of an operant discrimination task, with no effect on acquisition, discrimination or extinction. Repeated, but not acute, maternal stress was also associated with offspring hyperactivity. This highlights the differential impact of varying the stress schedule. Furthermore, use of multiple measures of learning uncovered a long-lasting, selective effect of relatively mild, indirect prenatal manipulation.

MONOTONIC AND RHYTHMIC INFLUENCES : A CHALLENGE FOR SLEEP DEPRIVATION RESEARCH

There are both monotonic and rhythmic factors in the patterns of change seen in physiological, psychological, and performance variables during sleep deprivation. These monotonic and rhythmic factors can be orthogonal, or they may interact with each other, with various task variables, or both. The importance of separating the rhythmic from the monotonic factors and of elucidating their interactions is discussed. Experimental methods and types of analysis appropriate to evaluating these factors are examined, with special emphasis on the complex demodulation time series analysis applied to group or individual subject data. The discussion is accompanied by data illustrations. It is suggested that sleep deprivation research should be designed so as to generate physiological and behavioral data that include information on both monotonic and rhythmic factors, the nature and extent of their interaction, and how they interrelate with systematically manipulated independent variables.

Cause and effect explanations of job satisfaction and commitment : the case of exchange commitment

ABSTRACT Although industrial psychology literature is replete with studies on job satisfaction and commitment, only Bateman and Strasser (1984) and Curry, Wakefield, Price, and Mueller (1986) have used longitudinal analysis to examine the relationship between the two variables. In an attempt to resolve some of the previous conflicting results, the present study analyzed the relationship between job satisfaction and an exchange theory of commitment. As part of a longitudinal study on attitudes and behavior, 63 Israeli police officers responded twice over a 5-month period to job satisfaction and commitment questionnaires derived from the Rusbult and Farrell (1983) model. A cross-lagged regression design showed that each variable was reliable and relatively stable, and that no causal relationship existed between commitment and job satisfaction.

The implications of sleep loss for circadian performance accuracy

Abstract The effect of sleep loss on circadian performance rhythms is discussed. Data are presented which indicate that the maxima and minima of the circadian component of performance curves are delayed by 2 to 4 h as a result of sleep deprivation. The consequences of such a change are discussed.

Latent Inhibition and Learned Helplessness in Children: Similarities and Differences.

Abstract Four experiments used a common set of procedures to investigate the occurrence and the generalization of learned helplessness (LH) and latent inhibition (LI) in 10- to 11-year-old children. In Experiment 1, preexposure to response-outcome independence impaired performance (i.e., LH) on two subsequent tests: The first was similar to the preexposure situation, the second was not. Moreover, LH occurred whether preexposure involved positive or negative feedback. On the other hand, noncontingent stimulus preexposure did not impair subsequent performance, i.e., LI was not obtained in the first experiment. Experiment 2 replicated the LH findings of Experiment 1: LH occurred following preexposure to response-independent feedback, regardless of whether that feedback was positive or negative, and LH generalized to a situation that was different from the preexposure situation. In addition, the stimulus preexposure procedures of Experiment 2 were embedded in a “masking” task and, under these conditions, LI was obtained. Nevertheless, LI did not generalize to a testing situation that was different from the preexposure situation. Experiment 3 demonstrated that noncontingent stimulus preexposure impairs performance relative to a nonpreexposed control group, that the effect is dependent upon masking, that masking alone produces no performance decrement, and that LI is, indeed, stimulus specific. In Experiment 4, preexposure to response-outcome independence impaired subsequent performance on similar and dissimilar tests whether feedback was consistently positive, consistently negative, or randomly positive and negative over trials. In addition, stimulus preexposure produced LI only under conditions of masking and even then, LI was not evident in novel test situations. The results are discussed in terms of common and different mechanisms underlying the LI and LH phenomena.

The circadian cycle effects of DSIP on colonic temperature, blood pressure, and heart rate in control and area postrema-lesioned rats

Groups of control and Area Postrema rats were treated with 0.1 mg/kg, i.p., DSIP or with saline, at 06:00, 09:00, 12:00, 15:00, 18:00, 21:00, 24:00, and at 03:00. Colonic temperature, blood pressure, and heart rate were measured 30 min after treatment. DSIP induced a shift in the hyperthermic cycle of control rats, but was unable to modify the noncyclic hypothermia found among Area Postrema-lesioned rats. Furthermore, DSIP caused a decrease in the blood pressure level of control rats, but had no such effect on the already depressed level of blood pressure in the Area Postrema-lesioned rats. Finally, DSIP decreased the heart rate of control rats and significantly antagonized the elevated heart rate observed in the Area Postrema-lesioned rats. The data do not permit us directly to relate the physiological change induced by DSIP to its sleep-promoting effects.

Sedative and stimulative music effects: Differential effects on performance impairment following frustration

The present report describes three experiments that examined the effects of sedative and stimulative music on performance decrement following frustration. A five-group design was used in the first experiment: No Treatment (NT), Frustration only (F), Frustration and Sedative music (F-SD), Frustration and Stimulative music (F-ST), and Frustration and Waiting (F-W). The second experiment assessed the differences in emotions associated with the two types of music, sedative and stimulative. After listening to each excerpt, subjects were required to report their feelings about each one, on a 15-point Semantic-Differential-type scale. The third experiment employed a three-group design: F-SD, F-ST, and F only. Music was also played during frustration manipulation. Results for the first experiment showed that while frustration plus sedative music reduced decrement in performance as compared with frustration only, stimulative music had no effect. The results of the second experiment showed that sedative music was highly correlated with calmness, tenderness, and contentedness, while stimulative music was related to tension, anger, boldness, and salience. The results of the third experiment were similar to those of Experiment 1 for effects of sedative music. Stimulative music, however, seemed to enhance the decrement in performance following frustration. The results are discussed with regard to the effects of music on performance, and the interaction of emotions and properties of sedative music in reducing the decremental effects of frustration on performance.

Selected problems of analysis and interpretation of the effects of sleep deprivation on temperature and performance rhythms.

One of the major methodological-analytic problems encountered by researchers in sleep deprivation involves the examination and analysis of the relationship between sleep loss and rhythmic influences on performance. The comparison of performance rhythms with physiological rhythms, e.g., body temperature, generated under the same conditions of sleep deprivation, has become an important means of testing for an endogenous source of the rhythmicity in the data and for clarifying the nature of the proposed oscillator system. Should the data sets be correlated before or after their separation into monotonic and rhythmic parts? Correlating the raw data without separating them into their components can yield negative results, while, in reality, some of the major underlying rhythms may be highly related. The example used in this chapter showed strong cross correlations of the circadian components of temperature and two performance tasks. Sleep deprivation is thus seen to interact with performance rhythms. This interaction is only revealed after the data are analyzed and broken into their component parts. This procedure leads to the conclusion that certain performance rhythms and temperature may share the same generating oscillators.

The impact of cognitive interference on performance during prolonged sleep loss

SummaryA study was conducted on the effects of off-task cognitions on performance during sleep deprivation. Subjects answered the Thought Occurrence Questionnaire, assessing their proneness to engage in off-task cognitions, and were deprived of sleep for 72 hours, during which they performed a variety of tasks including visual discrimination and three versions of a logical reasoning task in which cognitive load was varied systematically. In addition, every day subjects answered the Cognitive Interference Questionnaire, which taps off-task cognitions during the experiment. Results indicated that subjects who habitually engage in off-task cognitions performed worse during 72 hours of sleep loss than subjects who do not engage in such distracting activities. In addition, it was found that the engagement in off-task cognitions increased during the 72 hours of sleep loss and such an engagement was related to deficits in performance accuracy. The mechanisms of off-task cognitions and sleep loss underlying these effects are discussed.

Generality of US preexposure effects: Effect of shock or food preexposure on water escape

Mice preexposed to nonresponse-contingent shock offset or nonresponse-contingent food delivery performed more poorly in a water-escape task than groups receiving no preexposures or preexposure to controllable shock or controllable food. It was concluded that US preexposure procedures produce a very broad generalization of effects. These results are discussed in relation to similar findings in the literature.