Changes in functional response units with briefly delayed reinforcement

In two experiments, key-peck responding of pigeons was compared under variable-interval schedules that arranged immediate reinforcement and ones that arranged unsignaled delays of reinforcement. Responses during the nominal unsignaled delay periods had no effect on the reinforcer presentations. In Experiment 1, the unsignaled delays were studied using variable-interval schedules as baselines. Relative to the immediate reinforcement condition, 0.5-s unsignaled delays decreased the duration of the reinforced interresponse times and increased the overall frequency of short (<0.5-s) interresponse times. Longer, 5.0-s unsignaled delays increased the duration of the reinforced interresponse times and decreased the overall frequency of the short interresponse times. In Experiment 2, similar effects to those of Experiment 1 were obtained when the 0.5-s unsignaled delays were imposed upon a baseline schedule that explicitly arranged reinforcement of short interresponse times and therefore already generated a large number of short interresponse times. The results support earlier suggestions that the unsignaled 0.5-s delays change the functional response unit from a single key peck to a multiple key-peck unit. These findings are discussed in terms of the mechanisms by which contingencies control response structure in the absence of specific structural requirements.     

Typical delay determines waiting time on periodic-food schedules: Static and dynamic tests

Pigeons and other animals soon learn to wait (pause) after food delivery on periodic-food schedules before resuming the food-rewarded response. Under most conditions the steady-state duration of the average waiting time, t, is a linear function of the typical interfood interval. We describe three experiments designed to explore the limits of this process. In all experiments, t was associated with one key color and the subsequent food delay, T, with another. In the first experiment, we compared the relation between t (waiting time) and T (food delay) under two conditions: when T was held constant, and when T was an inverse function of t. The pigeons could maximize the rate of food delivery under the first condition by setting t to a consistently short value; optimal behavior under the second condition required a linear relation with unit slope between t and T. Despite this difference in optimal policy, the pigeons in both cases showed the same linear relation, with slope less than one, between t and T. This result was confirmed in a second parametric experiment that added a third condition, in which T + t was held constant. Linear waiting appears to be an obligatory rule for pigeons. In a third experiment we arranged for a multiplicative relation between t and T (positive feedback), and produced either very short or very long waiting times as predicted by a quasi-dynamic model in which waiting time is strongly determined by the just-preceding food delay.     

Accuracy of estimations of body-frame size as a function of sex and actual frame size

Body-frame size is an important factor in determining an optimal body weight for a given height. Previous studies have indicated that many individuals incorrectly estimate their body-frame size, and, as a result, incorrectly assess their ideal weight. The present study investigated the accuracy of estimation of body-frame size as a function of sex and actual frame size. The subjects were 66 men and 52 women participating in a community adult fitness program. Data indicated that medium-framed individuals were the most accurate in their estimations of body-frame size. Also, women were twice as likely to be accurate as were men. These results are interpreted to mean that most people assume they are medium-framed and that there is a sex difference in the way body-frame size is estimated.     

Effects of visual aids on acquisition of selected tennis skills

The study compared the effects of supplemental visual aids on the acquisition of selected tennis skills. The forehand and backhand drive placement tests of the Hewitt Tennis Achievement Test were used to pretest, midtest, and posttest 55 subjects who were assigned to one of three treatments: control (instructor's verbal feedback only), videotaped replay viewing (with instructor's feedback), and loop-film viewing (modeling, with instructor's feedback). Each received 1200 min. of instruction. There were no statistically significant differences among groups; however, empirical evidence suggested that the use of videotaped replay and loop-film technique has merit and might be given consideration for use in instructional settings.     

Psychophysiology of analysis of connotative decodification: the role of thermic and somesthetic systems in decodification of chromatic stimuli

We hypothesized that in the decodification of connotative aspects of visual chromatic stimuli the periphery of the body plays an important role. In particular we hypothesized that the decodification process of so called "warm" and "cold" colours is related to a real modification of the temperature of the body which is the basis of the "subjective feeling" and of the attribution of the "emotional meaning" to the stimulus. So we have measured the temperature of the body of 36 female psychology students while they were looking at a luminous screen through spectacles in which filters (coloured lenses) of different colours were placed. Analysis indicated that during the perception of so called "warm" colours a statistically significant increase in the temperature of the body appeared. We observed an enhancement of temperature on the left side of the body during the perception with red and yellow filters and a small increase in temperature on the right side of the body with orange and yellow filters. In the discussion of the results we considered also the role of the cerebral dominance in decodification process of the connotative components of stimuli.     

Intentional and incidental visual memory as a function of cognitive level and color of the stimulus

Performance of two groups of youngsters, educable mentally retarded (CA 15-5; MA 11-4; IQ 74.3) and those of average ability (CA 10-5; MA 11-3; IQ 109.1) was compared for intentional and incidental visual memory as a function of cognitive level and color of the stimulus. Nonretarded subjects performed significantly better than the retarded ones of equal MA. Both groups performed better with a color than black-white card, and both groups did better on the tasks involving intentional rather than incidental memory.     

Effects of eye color on frisbee toss

Light-eyed individuals generally perform better at self-paced activities while dark-eyed individuals perform better at reactive activities. Using multiple regression it was found that dark-eyed students hit a target with a frisbee more times than did light-eyed students.     

Psychological gender, hand preferences, and sex differences in book-carrying styles

Individuals with stronger sex-role identities may be expected to show greater conformity to sex-typed behaviors. Proceeding from this assumption, the sex-role status and sex of students using different styles of carrying books were compared. This study also examined whether over-all hand preference or age were related to carrying styles or sex-role status. Subjects completed a questionnaire comprised of the 24-item Personal Attributes Questionnaire of Spence and Helmreich, a 6-item scale of hand preference and a self-rating of sex-role identity. Afterwards, each subject's carrying style was covertly observed and recorded. Most subjects carried their materials in a sex-typical way or in book bags (for which no sex-typed carrying styles were discovered). As in previous studies, men in this study scored higher than women on masculinity and androgyny and lower on femininity. Hand preference was not related to sex-role status. Carrying style was not significantly correlated with any of the predictor variables for men, perhaps because almost no variance in carrying style was observed among them. Women who used masculine carrying styles tended to be older, have greater instrumentality, and a more masculine identity.     

Fixation accuracy and perceptual asymmetry for consonants

Fixation accuracy was related to perception of laterally presented consonants. Small left-eye fixation inaccuracy influenced perceptual performance of 8 men and 8 women.