A COMPARATIVE STUDY OF INSTRUMENTAL LEARNING BY PRESCHOOL CHILDREN IN PAPUA NEW GUINEA AND AUSTRALIA1

Instrumental learning of preschool children in Papua New Guinea (PNG) and Australia (AUST) was compared using two tasks (imitative and nonimitative) and two rewards (social and nonsocial). There were no differences between the two groups in the rate of acquisition measure of trials to criterion. PNG children made more late responses during acquisition and, for nil responses, there were group x task and group x reward x task effects. In the extinction phase, there were two main effects for trials to criterion: PNG children were more resistant to extinction than AUST children, and there was greater persistence in responding after social reward regardless of nationality. Reward x group, reward x task, and reward x group x task interactions also were observed in the extinction trials to criterion. In addition, there were three main task effects during extinction for other responses: on the imitative task, more wrong responses were made, and on the nonimitative task, more extra responses and more paired responses were made. A subsidiary analysis compared the two culturally different but educationally similar groups comprising the PNG sample: no major differences were isolated in acquisition or extinction.     

Semi-automated desensitization : a controlled clinical trial

A clinical trial of semi-automated desensitization on phobic patients. Twelve received treatment with a therapist present and 12 received treatment from pre-recorded tapes. Therapy lasted a maximum of 16 weekly sessions. Assessment of progress was by means of self-ratings of phobic behaviour and more global fear ratings, made by the referring psychiatrist. Both treatments produced beneficial results. Both ratings agreed in finding no significant differences between the two methods of administration, thus confirming results from existing non-clinical trials of automated desensitization. Regardless of treatment group, agoraphobics and social phobics tended to improve less markedly, and less rapidly than simple phobics. Some implications of automated therapy for clinical practice are discussed.     

Positive and negative social ties among older adults: Measurement models and the prediction of psychological distress and well-being

The factor structure of positive and negative social ties was studied among 246 older adults who were either recently physically disabled, recently conjugally bereaved, or matched controls. Covariance structure analyses were carried out on a network measure to determine whether positive and negative social ties represent independent domains of social experience, and to assess the degree to which their structure is invariant across groups undergoing major loss transitions. Positive and negative social ties were found to be independent and there was substantial similarity in their factor structure across the three groups. Hierarchical regression analyses revealed that, whereas positive social ties were related to psychological well-being, negative social ties were predictive of both psychological well-being and distress. These results demonstrate the importance of assessing both positive and negative ties in explaining the psychological adjustment of older adults.     

Evidence of acoustic coding in long-term memory

Contrary to previous indications, retroactive interference in long-term paired associate learning was found to be a function of acoustic similarity. Experimental groups were exposed to the A-B, A'-C paradigm where corresponding stimuli were homophones. Their retention scores were substantially and significantly lower than control groups run with an A-B, C-D paradigm. The failure of previous studies to reveal effects of acoustic similarity in this way is attributed to the use of an insufficiently high degree of similarity.