Visual short-term memory, response delay, and age

Recall and recognition memory performance of 12 young (M = 19 yr.) and 12 older (M = 72 yr.) females was studied in relation to response delay (5, 25, and 125 sec.) and stimulus complexity (6.1 and 13.7 bits of information). The subjects were matched on verbal IQ, visual acuity, and educational levels. Stimuli were abstract, black and white, 4 X 4 square matrices. Age-related decrements in memory performance were associated with stimulus complexity but not with response delay. Older subjects also reported experiencing encoding difficulties during the registration phase. The results were discussed with reference to the locus of age-related decrements in visual short-term memory.     

Sex differences in reinforcement and punishment on prime-time television

Prime-time television programs were analyzed for frequencies of positive reinforcement and punishment exchanged among performers varying in age and sex. Results indicated that most responses were given by and directed to adult males. Moreover, while adult males exhibited and received similar frequencies of reinforcement and punishment, adult females were likely to give and to be the recipients of more reinforcement than punishment. Proportional analyses which controlled for sex differences in frequencies of responses revealed that females more often exhibited and received reinforcement, whereas males more often exhibited and received punishment. Results are interpreted from a social learning theory perspective and the implications for children's learning of positive and negative behaviors are explored.     

Exercise, changes in aerobic capacity, and changes in self-perceptions: An experimental investigation

Subjects in an exercise training condition participated in a 10-week aerobic exercise class, whereas subjects in waiting-list control and independent control conditions did not. The results indicated that subjects in the training condition evidenced reliably greater improvements in physical fitness (aerobic capacity) and reported reliably greater improvements in their abilities and confidence in both the physical area (e.g., ability to run distances) and nonphysical area (e.g., frustration tolerance) than did subjects in the control conditions. On the other hand, improvements in physical fitness were not related to reported improvements in abilities and confidence. These findings are of interest because they indicate that some of the important personal changes that are associated with physical fitness training are not due to changes in fitness, but appear to be due to other factors (e.g., group participation and expectancies).     

The development of young children's awareness of logical inconsistencies

Research by Markman (1979) suggests that children up to 12 years of age do not spontaneously detect logical inconsistencies. The present study was directed to factors which may limit children's ability to recognize their failures to understand. A task was devised which involved materials that were clearly based on children's experiences, and which involved premises and conclusions which were presented contiguously, rather than being interspersed among other sentences. Ninety-six 5-, 6-, and 7-year-old children were asked to judge the acceptability of eight three-sentence “stories” told by a puppet, and were asked to justify their responses. The stories differed in whether they were consistent or inconsistent, and in whether the principle upon which a story's consistency depended was implicitly or explicitly stated. The results showed developmental differences. By Age 7 years, most children were quite capable of evaluating sentences for their logical consistency. Five-year-olds, however, did not perform as well on the task, especially when the information upon which the logical cohesiveness of the stories rested was implicitly, rather than explicitly, stated. An examination of the justifications provided by these children revealed that they tended to question the empirical validity of individual sentences, rather than integrate the story as a whole and examine its overall logical structure.     

Children's representation of knowledge in verification

Thirty-two children aged 8–9 and 10–11 were asked to perform two statement verification tasks. Task 1 consisted of statements that were likely to elicit an affirmative knowledge representation,You have three eyes, is likely to elicit the representation,I have two eyes. Task 2 consisted of statements that were likely to elicit a negative knowledge of representation,You have a tail, is likely to elicit a negative representation,I do not have a tail. All statements varied in two dimensions, polarity (affirmative vs. negative) and truth value (true vs. false). Negative statements in Task 1 were found to be more difficult for children to verify than those in Task 2. This performance difference was used to infer the form of knowledge representation generated in verifying negative statements.     

The Effect of Clear Evaluation Criteria on Sex Bias in Judgments of Performance

Previous research indicates that the work of women is often devalued rela- tive to that of men. Two experiments tested the hypothesis that such sex bias appears when judges follow ambiguous guidelines or criteria in making evalua- tions, but not when they tollow clear evaluation guidelines. In each experiment, male and female undergraduates evaluated a performance that was attributed to either a man or woman (an intellectual test performance in Experiment I; an artistic craft object in Experiment 11). Subjects followed either clear, explicit evaluation criteria or vague, ambiguous criteria. As predicted, female subjects Lyaluated the "female's" performance less favorably than the "male's" only when. criteria were vague. In contast, male subjects showed little evidence of sex bias, regardless of the criteria they followed. Discussion centers upon: (1) possible cognitive processes underlying the observed effects of clear criteria; and (2) potential practical applications designed to alleviate sex bias in naturalistic settings.     

An electronic cine camera system for the automatic collection and analysis of high-speed movement of unrestrained animals

A system is decribed that collects visual data using a solid-state photodiode image sensor at rates of up to 600 frames/sec in a binary format suitable for image-analysis techniques. Of particular interest is the system’s ability to analyze high-speed movement of animals without prior modification of the subject (e.g., attachment of lamps or reflectors to the subject).