Risky decision: Attention effects or masking effects?

The Marshak bid procedure shows that more money is required to induce a S to exchange gamble a for gamble e and then e for b if e differs from a only in the winning amount and differs from b only in the probability of winning, rather than if e differs from a only in the probability of winning. This is contrary to most theories of risky decision making which imply that the amount of money necessary to effect a 2-step exchange between a and b should be independent of the intermediary gamble. One might attempt to explain the effect by saying that the S attends to the dimension which is different between gambles. But the explanation is untenable if one assumes that states of attention are defined as weightings of the dimensions. An alternative explanation is put forward which basically assumes that winning amounts mask differences in probability of winning more than vice versa. The formalization of the theory is given in terms of Fechnerian integration over imperfect differentials.     

Effects of positive and negative adult-child interactions on children's social preference

The effects of positive and negative interactions on children's performance and preferences for the adults associated with each type of interaction were studied. Five children served as subjects during daily sessions in which each of three adults followed prescribed patterns of social interaction. One adult (positive) dispensed positive comments contingent upon either color-sorting or completion of arithmetic problems; a second adult (negative) mildly reprimanded the child for off-task behavior; and the third adult (extinction or nonreactive) said nothing to the child when he was present. Following each session the three adults reentered and the child chose one of them for an additional period of interaction. Three response measures (frequency, latency, and percent of time on-task) and children's adult preferences were obtained daily. The negative adult affected the most task behavior and had strongest stimulus control; the positive adult, though exerting little control over children's behavior, was the most preferred. Children's adult preferences were not specific to the task setting, but were observed across a variety of contexts.     

Progressive elaboration and memory for order in children

Three experiments were conducted investigating memory for items and order in a progressive elaboration paired-associates task. For all subjects retention of item information was improved by the use of progressively elaborated interactions relative to a no-elaboration control condition. For second and fourth graders, retention of order information depended upon the type of elaboration. If successive interactions were added in a logical temporal order, retention (of order information) was superior to the case where the successive interactions were added in a random order. This effect was not obtained with kindergarten children. In the second and third experiments, kindergarteners were instructed regarding the sequencing of the successive items, and results similar to those obtained with older children ensued. The data were discussed in terms of Tulving's distinction between episodic and semantic memory.     

The role of contextual cues in mediating transfer

An experiment was conducted with sceond-grade children to test the hypothesis that contextual (task format) changes limit the transfer of learning. The Ss learned two problems employing different formats concurrently and were then given a single transfer problem similar in format to one of the training problems. The transfer data were predictable from a consideration of the similar format training problem and independent of the different format training problem. This indicated that contextual cues were stored during training and played a role in determining transfer.     

Auditory-verbal short-term memory impairment and conduction aphasia

The specific impairment of performance on repetition tasks has classically been identified with conduction aphasia. It is argued that this impairment can be subdivided and a deficit in span performance distinguished from that of the reproduction of single words. An explanation of the span deficit in terms of auditory-verbal short-term memory is preferred to hypotheses involving disconnections or damage to order retention systems. It is shown that a short-term memory component is present in many patients previously classified as conduction aphasics.     

Treatment of dental fears by imaginal flooding and rehearsal of coping behaviour

All combinations of high versus low arousal imaginal flooding, and coping versus no-coping imaginal rehearsal, were compared in the modification of dental fear. About one half of all subjects seen successfully completed dental treatment, although significant differences were found between groups in anxiety reduction before and during dental examination, which favoured the low arousal flooding groups. Coping rehearsal did not influence anxiety, but interacted with arousal level of flooding to determine subsequent dental attendance. The results suggest that flooding without coping rehearsal had little effect at high levels of arousal, but good results at low levels. Flooding with coping rehearsal on the other hand, had mixed results. At high arousal levels avoidance was reduced but not anxiety, while at low levels anxiety was reduced but not avoidance. The implications for further research on coping rehearsal are discussed.     

Effect of punishment on human variable-interval performance

Three female human subjects pressed a button for monetary reinforcement in a range of variable-interval schedules specifying different frequencies of reinforcement. On alternate days, responding was also punished (by subtracting money) according to a variable-ratio 34 schedule. In the absence of punishment, rate of responding was an increasing negatively accelerated function of reinforcement frequency; the relationship between response rate and reinforcement frequency conformed to Herrnstein's equation. The effect of the punishment schedule was to suppress responding at all frequencies of reinforcement. This was reflected in a change in the values of both constants in Herrnstein's equation: the value of the theoretical maximum response-rate parameter was reduced, while the parameter describing the reinforcement frequency corresponding to the half-maximal response rate was increased.     

The effect of signaled reinforcement availability on concurrent performances in humans

During Phase I, three female human subjects pressed a button for monetary reinforcement in two-component concurrent variable-interval schedules. Five different reinforcement frequencies were used in component A, whereas the reinforcement frequency in component B was held constant. Absolute rates of responding conformed to equations proposed by Herrnstein to describe concurent performances, and the ratios of the response rates and the times spent in the two components conformed to the matching law. During Phase II, the availability of reinforcement in component A was signaled by the illumination of a lamp. This resulted in suppression of response rates in component A and elevation of response rates in component B, these changes being reflected in a distortion of the matching relationship which took the form of a bias in favor of component B.