Reflex modification in the rat: the inhibitory effects of intensity and frequency changes in steady tones

In laboratory rats (as in humans) a low-intensity tone that precedes a high-intensity burst of noise by approximately 100 ms can reduce the amplitude of the startle reaction elicited by the burst of noise. A series of four experiments with rats investigated the relation between the inhibitory effects of tonal frequency change and the length of the silent period (gap) preceding it. The major findings were the following: (a) A gap in an otherwise continuous pure tone inhibited startle when the gap occurred approximately 100 ms prior to the noise burst. (b) Although an increase in gap duration increased the inhibition afforded by the gap, the maximum inhibition was yielded by gaps of 100 ms and greater; this maximum was equivalent to the inhibition yielded by the presentation of a postgap tone alone. (c) A shift in tonal frequency across a 10-ms gap yielded more inhibition than did the same gap with no frequency shift; again the shift yielded equivalent inhibition to the presentation of the postgap tone alone. (d) An increase in the frequency shift increased inhibition when the shift occurred across a 10-ms gap, but not when the shift occurred across a 100-ms gap.     

A longitudinal study of the development of spatial conceptual ability

During October and November of 1983, three subsamples were selected from three schools in Mesa, Arizona: 34 students in 6th grade, 34 students in 8th grade, and 34 students in 10th grade. A battery of Piagetian-type tasks were individually and randomly administered to each subject. Seven tasks examined projective spatial conceptual abilities, and three tasks examined Euclidean abilities. The same battery of tasks was again administered to the same subjects during November and December of 1984 when all the subjects were in the next grade, that is, 7th, 9th, and 11th. Because of attrition, the number of students tested during the second year were 33, 30, and 28, respectively. To test for significant differences between grade levels, a chi-square one-sample procedure was used. Out of a possible 50 tasks, significant differences were detected in 36 (72%). Those findings, along with an examination of the percentage of students passing each task, support the notion of sequential development of spatial conceptual abilities.     

Contributions of Social Psychology to the Study of Appetltive Behaviors1

Social psychology has contributed substantially to the study and understanding of appetitive behaviors. This paper focuses on three major lines of social psychological research that have made particularly important contributions to appetitive behaviors: Hovland's work on attitudes and attitude changes, Bandura's social learning theory, and Schachter's studies of obesity and cigarette smoking. The relevant work of these three social psychologists and the research following from each line of inquiry are reviewed. Additional potential applications of these social psychological approaches to the study of appetitive behaviors are discussed.     

Professional involvement in self-help groups for parents of high-risk newborns

Patterns of professional involvement and control in self-help groups were studied through a questionnaire completed by representatives of 63 self-help groups for parents of high-risk newborns located throughout the United States. Results indicated that when professionals began a group, they were likely to continue to maintain control over it. Groups controlled by professionals were more likely to utilize professional counseling as a form of support and less likely to provide outreach services to parents following hospital discharge of their infants. Group stability, growth, and innovation were associated with more consultation between parents and professionals in the planning process.     

Context and strategy in acquiring temporal connectives

There has been considerable debate over the role of comprehension strategies in the acquisition of temporal connectives. This study examined the role of caluse logic and interpretational strategies in the acquisition of temporal words; age-related changes were also considered. Thirty-two children between 3 and 5 years of age served as subjects. Sentences with a variety of temporal words were used to tap children's comprehension of before, after, when, while, just before that, and and after that. Clause logic was found to significantly improve the understanding of these sentences. However, the order of mention and main clause first strategies were used infrequently. Apparently, when children respond to sentences that describe information in a way that is consistent with that they normally hear, these strategies are seldom applied.I wish to express my thanks to Janice Bogen, who assisted in data collection, and to Erika Hoff-Ginsberg, who assisted in some of the data analysis.     

The relationship of affiliative arousal to dopamine release

Higher levels of affiliation motivation after exposure to affiliative films are significantly related to higher dopamine concentrations in saliva in one study of 61 college students of both sexes, and in plasma in another study of 47 adults of both sexes. Individuals high in dispositionaln Affiliation, if they also reported high life stress, showed high gains in dopamine concentration in plasma after exposure to an affiliative film significantly more often than other individuals. Since aroused affiliation motivation was not associated with higher concentrations of norepinephrine, epinephrine, or cortisol in either study, it appears likely that dopamine is especially associated with arousal of affiliation motivation, just as norepinephrine has been found to be associated with arousal of power motivation. Thus, different motives may be subserved by different hormones, making it unlikely that all motives lead to the same state of physiological arousal.This research was carried out when all the authors were connected with the Department of Psychology and Social Relations at Harvard University. We acknowledge with thanks the support of the John D. and Catherine T. MacArthur Foundation through a grant to the senior author.     

A scale for measuring persistence in children

Persistence and its assessment have been studied since the 1920s. One common approach in measuring persistence has been through testing the subject's ability to solve difficult or monotonous problems. Another approach has been through questionnaires. Although persistence is very important in academic achievement and in the general development of personality, no questionnaires have been developed for measuring persistence in children. The present research concerns the development of such a scale. It includes 40 items and was tested on 322 Israeli children aged 7-13. The internal reliability of the scale (Cronbach alpha) was .66, and the test-retest reliability after 6 months was .77. The scale differentiated active gymnasts from non-gymnasts as well as persistent gymnasts from dropout gymnasts. In addition, significant correlations were found between the scale and the need-persistence measure of the Rosenzweig Picture Frustration Study, Locus of Control, and other measures. We discuss these findings along with the significance of persistence in everyday life.