Effects of quantitative shifts in a visual reinforcer on the instrumental response of infants.

Two studies examined the effects of quantitative (“complexity”) differences in a visual reinforcer and subsequent reward shifts, on operant response rates. Footkicks and visual attention of 3-month-old infants were measured across daily sessions with conjugate reinforcement provided by an overhead mobile containing either two, six or ten identical components. In Experiment 1, initial rates to the three mobiles differed. The relation between components and kicking was not linear, but was an inverted U-shaped function of component numerosity. The infant responses as a function of numerosity from Experiment 1 were used to define “complexity” in Experiment 2, and all subjects were switched to an intermediate complexity level (two components) after achieving a criterion of stable responding. Although the number of mobile components did not differentially affect acquisition rates, infants who received a shift from six to two components exhibited a reliable and immediate response increase whereas those experiencing a ten- to two-component shift exhibited negative behaviors. These results imply that infants respond relationally, actively manipulating their visual environments as a function of their previous contextual experiences.     

Recognition versus recall of briefly presented visual information: a developmental study.

Five-year-olds, as compared to adults, have displayed a striking constraint on short-term recognition memory for briefly presented visual information. In the present study, a recall paradigm was also examined to test the generality of this constraint. Additionally, we examined the possibility that forced verbal report might differentially enhance children's performance. Evidence of improved performance in children would suggest that a verbal encoding strategy, used by adults only during the recognition task, is activated in children in a recall task. Though recall memory performance of young children did surpass recognition memory levels, the same was true for adults with the relative adult-child difference remaining constant across conditions. It was concluded that processes other than verbal labeling (e.g., buffer storage, organization, retrieval) are probably more responsible for age differences in immediate memory performance than labeling, per se.     

Effects of uncertainty,delay, and focus of attention on reactions to an aversive situation

The hypotheses of informational cognitive control, based on the idea that being able to predict the occurrence of an unpleasant event facilitates a reduction of its impact, has not received clear support in previous research. The present experiment investigated the effects of three variables on subjective reactions to mild electric shock: (1) temporal uncertainty about when the shocks would occur, (2) the period of delay before the shock, and (3) attention to either the sensory properties of the shocks or emotional reactions to them. The results showed that low temporal uncertainty and short periods of delay led to reduced anxiety during the period preceding the shock but did not reduce the reported intensity of the shocks themselves. Higher ratings of both shock intensity and distress were obtained when the focus of attention was on the sensory properties of the stimuli rather than on the affective reactions to them. It was concluded that (i) the attentional focus of the subject is an important determinant of rated stimulus effects, and (ii) prediction, though it may reduce prestimulus anxiety, has no real effect on the impact of the stimulus itself.     

On mediating equity,equality, and self-interest: The role of self-presentation in social exchange

Do individuals conform to various norms of reward allocation not necessarily in response to internal standards but rather, to win approval from relevant others? This study examined the role of self-presentation in mediating equity, equality, and self-interest within reward allocations. It was hypothesized that when others were aware of a subject's behavior, distributions would reflect that person's normative definition of the situation. Subjects allocated a $5.00 payment among themselves and three partners with unequal performance inputs. Informing the experimenter of one's decisions resulted in more equitable divisions, characterizing the employment-productivity relationship between experimenter and subject. When co-workers, defined as peers, were aware of allocations, an equality-based solution was favored. Allocators enhanced their own rewards beyond normative values only when their choices were completely private. Evidence was also found of postdecisional cognitive changes which maintained the belief that one acted justly in giving each partner what he deserved. These findings are consistent with the proposition that individuals maximize their own rewards, defined broadly to include social impression-formation and intrapsychic benefits. Apparently, self-presentational concerns mediate the relative salience of equity, equality, and self-interest in social exhange.     

The nature of equity-restoration: Some approval-seeking considerations

Subjects performed a proofreading task and evaluated its difficulty both beforehand and afterwards. They were overpaid or equitably paid by an experimenter who was or was not directly responsible for the level of pay they received, and who they believed would or would not see their post-test ratings. All subjects knew the experimenter would grade their task performance. Consistent with equity theory, overpaid subjects rated the task as having been more difficult than they had expected and did higher quality work than did equitably paid subjects. However, subjects who thought the experimenter would see their ratings (Aware condition) rated it as more difficult and performed more poorly on it than those who thought she would not see them (Unaware condition). Reported task difficulty increased among overpaid subjects under aware conditions, remained stable among overpaid subjects under unaware conditions, and decreased for equitably paid subjects. These findings suggested that what appears to be “equity-restoration” may be a self-presentation strategy designed to win the experimenter's approval, and that task ratings rather than performance will be used for this purpose when they can be communicated to the experimenter. The experimenter's responsibility for the subject's pay had no effect in the present study.     

Psychophysical scaling of stimulus similarity in 3-month-old infants and adults

The ability of 3-month-old infants to discriminate novel components of a prefamiliarized stimulus was assessed using an operant paradigm. Subjects were familiarized with the standard stimulus (five-component mobile) in three daily conditioning sessions and then were exposed to a comparison mobile containing from zero to four novel components substituted for familiar elements at the outset of a fourth daily session. Although a reliable reduction in mean number of footkicks was found only when an extreme number of components was substituted, log-log plots of infant response as a function of degree of novelty indicated that discriminability was described by a power function. Adult judgments of the similarity between the standard mobile and each degree of novelty were also described by a power function, suggesting a common basis may underlie the perception of similarity in the two groups. The finding of a power function for infant response to visual novelty is consistent with reports of similar discriminability functions in infant olfaction and audition. However, duration of visual fixation increased nondifferentially to all test stimuli, irrespective of degree of novelty. The latter finding is inconsistent with predictions arising from the visual attention literature.     

Feedback and fidelity: Effects of contingent consequences on accuracy of imitation

Accuracy of imitation by sixty kindergarten subjects was examined using a task in which a female adult modeled a series of pegboard patterns and delivered accuracy-contingent feedback. Four methods of feedback and a nofeedback control were compared. All four feedback groups were more accurate than the control group. The feedback conditions were: positive only, negative only, positive and negative, and negative with correction. The last condition resulted in greater accuracy than the others, which did not differ. All groups, including the control, improved significantly over trials. Accuracy of performance on interspersed, nonfeedback trials was maintained by feedback to the other patterns. Finally, imitation of repeating stimulus patterns did not differ from performance with nonrepeating patterns.     

Nonverbal discrimination of more and fewer elements by children

Fifty-six prekindergarten and 174 kindergarten children learned to choose either the card with more or the card with fewer elements in simultaneous discrimination problems. Learning was faster when the card with more elements was positive, particularly when a zero-element card was involved. This difference appeared to be attributable in part to an initial preference for “more.” On transfer trials involving all possible pairings of the training cards, subjects generally performed as though their choices were governed by the concept “more” or “fewer”. This tendency increased with age and with experience in the situation, even though conditions made verbal mediation appear unlikely.     

Density,perceived choice,and response to controllable and uncontrollable outcomes

Two experiments were designed to consider the effects of chronic high residential density on responses to choice and controllable and uncontrollable outcomes. In the first study, children responded to obtain candy as reinforcement and, during certain phases of the procedure, were able to select a schedule, if they chose, which allowed them to pick their own candy rather than having the experimenter select candy for them. Children who lived in high residential density were significantly less likely than children from less dense homes to try to control the administration of available outcomes. In the second study, children were preexposed to a solvable or unsolvable cognitive learning task and tested for how well they subsequently learned a solvable problem. Children from high density homes did significantly more poorly than less crowded children when the first problem was unsolvable. It was suggested that chronic density limits prediction and control in the home environment and consequently leads to the development of decreased expectancies for contingency between response and outcome in other control-relevant situations.     

Decision processes in children's recognition memory

Kindergarteners and third graders were given a continuous recognition memory task involving two-digit numbers. In addition, a rating scale consisting of photographs of various facial expressions was used to obtain confidence judgments from the Ss. Conventional analyses as well as signal detection analyses of the data revealed the following results: (a) the overall performance of the third graders was superior to that of the kindergarteners; (b) memory strength decreased as the number of intervening items increased; (c) there was no difference in the forgetting rates of the two grade levels; (d) the third graders exhibited a more liberal response bias than the kindergarteners; (e) both the hit rate (probability of correctly labeling an old stimulus as old) and the false-alarm rate (probability of incorrectly labeling a new stimulus as old) increased across blocks of items; (f) the increases in the hit rate and the false-alarm rate over blocks were due to a change in criterion from a relatively conservative level to a more lenient one; (g) the lower the S's level of confidence in judging an item as old, the lower was the probability of that item actually being old; (h) the third graders were better than the kindergarteners at gauging the accuracy of their recognition responses. It was concluded that with respect to recognition memory, chidren as young as $\text{5}\text{1}\text{2}$ years old are capable, to some extent, of monitoring their own memory states.