EVALUATION OF REINFORCER PREFERENCES FOR PROFOUNDLY HANDICAPPED STUDENTS

Five students classified as profoundly/multiply handicapped were trained to use microswitches to indicate reinforcer preferences. The students were trained to emit a designated motoric response (raise arm or raise head) which in turn activated a microswitch. The microswitches were connected to battery-operated toys and devices, and served to provide immediate, contingent consequences tothe students for their motoric responding. The results of the investigation were evaluated within a multiple baseline (across students) with alternating treatments (potential reinforcers) design. During baseline, the students were provided withthe switches and devices, butthe switches were not connected tothe devices. Duringthe training conditions, the switches activatedthe devices. Evaluation of the devices was conducted by recordingthe cumulative frequency and duration of the students' responses. Whenthe microswitches activatedthe devices during training, a substantial increase inthe duration of motoric responding occurred for all students. In addition, some students performed differentially across devices, suggesting that they had reinforcer preferences.     

Towards defending a semantic theory of expression in art: revisiting Goodman

Abstract

Nelson Goodman’s attempt to analyse the expressiveness of artworks in semantic terms has been widely criticised. In this paper I try to show how the use of an adapted version of his concept of exemplification, as proposed by Mark Textor, can help to alleviate the worst problems with his theory of expression. More particularly I argue that the recognition of an intention, which is central to Textor’s account of exemplification, is also fundamental to our understanding of expressiveness in art. Moreover I propose that the recognition of this intention depends on our interpretation, of the artwork–an insight Goodman tried to capture with his assertion that our attributions of expressive properties to artworks function metaphorically. The realisation of the context-dependence of our expressive judgements about art and, hence, of the central role interpretation plays in these judgements, I contend, counts in favour of theories of expression like Goodman’s that focus on semantic concerns.     

On historicity,context and the existence of African philosophy

Abstract

The author reviews the second edition of Philosophy from Africa by comparing it with the first edition and with other anthologies in African philosophy. Questions regarding the existence and identity of African philosophy receive special attention. It is argued that a negation of the existence of African philosophy results from monolithic, ahistorical and decontextualized thinking about Africa and about philosophy. The roots and development of African philosophy are inseparably bound up with the continent’s historical, political, cultural and economic complexities. The challenge facing African philosophers is twofold: deconstructing the notion of philosophy as constructed and conceived by the West; and reconstructing the history of African philosophy.     

Perceptions of treatment control moderate the daily association between negative affect and diabetes problems among adolescents with type 1 diabetes

Perceived control over diabetes may serve to buffer the relationship between adolescents' experience of daily negative affect and daily problems with diabetes. In a daily diary study including 209 adolescents (ages 10.5-15.5) with type 1 diabetes, we examined how daily affect related to daily fluctuations in experience of diabetes problems, and whether perceptions of control moderated these daily associations. Using hierarchical linear modelling, we found that day-to-day experiences of negative affect were associated with more frequent daily diabetes problems. Perceptions of treatment control moderated associations between negative affect and number of problems; negative affect was more strongly associated with number of problems among teens perceiving lower versus higher treatment control over their illness. The same pattern of association was not apparent for personal control. Results suggest that perceived treatment control may help to buffer detrimental associations between negative affect and adolescents' ability to successfully manage their diabetes.     

Intrusion, avoidance, and daily negative affect among couples coping with prostate cancer: a dyadic investigation

In the present study we examined how husbands' and wives' intrusive thoughts of prostate cancer (i.e., thinking about it when not meaning to) and avoidance (i.e., efforts to not think about cancer) related to their own and each other's average negative affect over a subsequent 14-day period. We examined whether congruence or similarity in intrusion about illness, but not avoidance, would be associated with less negative affect as this response to cancer could potentially facilitate adjustment. Fifty-nine husbands and wives completed measures of intrusion and avoidance after the diagnosis of prostate cancer and reported on their daily negative affect for 14 days. Using the actor-partner interdependence model, both patients and their wives who had high levels of intrusive thoughts experienced less negative affect when the other member of the couple also experienced high levels of intrusive thoughts. Those who had higher levels of avoidance had spouses who had higher levels of negative affect regardless of their own levels of avoidance. Congruence in responses to cancer may be adaptive for intrusion but not avoidance because the use of intrusive thoughts by both husbands and wives can allow couples to process the diagnosis of cancer, facilitating psychological adjustment, whereas avoidance does not. The current investigation adds to our understanding of how people within a marital dyad affect each other as they adjust to a cancer diagnosis.     

“Plateau”-related summary statistics are uninformative for comparing working memory models

Performance on visual working memory tasks decreases as more items need to be remembered. Over the past decade, a debate has unfolded between proponents of slot models and slotless models of this phenomenon (Ma, Husain, Bays (Nature Neuroscience 17, 347-356, 2014). Zhang and Luck (Nature 453, (7192), 233-235, 2008) and Anderson, Vogel, and Awh (Attention, Perception, Psychophys 74, (5), 891-910, 2011) noticed that as more items need to be remembered, “memory noise” seems to first increase and then reach a “stable plateau.” They argued that three summary statistics characterizing this plateau are consistent with slot models, but not with slotless models. Here, we assess the validity of their methods. We generated synthetic data both from a leading slot model and from a recent slotless model and quantified model evidence using log Bayes factors. We found that the summary statistics provided at most 0.15 % of the expected model evidence in the raw data. In a model recovery analysis, a total of more than a million trials were required to achieve 99 % correct recovery when models were compared on the basis of summary statistics, whereas fewer than 1,000 trials were sufficient when raw data were used. Therefore, at realistic numbers of trials, plateau-related summary statistics are highly unreliable for model comparison. Applying the same analyses to subject data from Anderson et al. (Attention, Perception, Psychophys 74, (5), 891-910, 2011), we found that the evidence in the summary statistics was at most 0.12 % of the evidence in the raw data and far too weak to warrant any conclusions. The evidence in the raw data, in fact, strongly favored the slotless model. These findings call into question claims about working memory that are based on summary statistics.     

Illusory Superiority in Self-Reported Memory of Older Adults

Older adults (N = 117, 46-89 years) compared their memory to that of age peers, 25-year-old young adults, and their own performance at the age of 25. In line with social comparison theory, most participants were very positive about their memory when age peers and young adults were the points of reference. When participants compared their present to their past memory, however, they reported decline. Surprisingly, only about half of the participants expected future memory decline. Contrary to prevailing stereotypes, all types of memory judgments were only weakly related to age. When using self-reports in research and in clinic it is important to remember that subjective judgments are useless unless participants are given a specific standard against which to evaluate their own functioning.     

Cross-sequential analysis of genetic influences on cognitive ability in the swedish adoption/twin study of aging

Abstract

Cross-sequential methods of analysis were applied to cognitive data from the Swedish Adoption/Twin Study of Aging. Thirteen measures of cognitive ability assessing four major domains (verbal, spatial, memory, and perceptual speed) were collected at two times of measurement separated by a three-year interval. Data were available from 41 pairs of monozygotic twins reared apart (MZA), 54 pairs of monozygotic twins reared together (MZT), 86 pairs of dizygotic twins reared apart (DZA), and 73 pairs of dizygotic twins reared together (DZT) ranging in age from 41 to 84 years. Cross-sectional differences and longitudinal changes in total variance and sources of variance were examined. With a few exceptions, both cross-sectional and longitudinal stability were found for total variance. In addition, few cross-sectional differences and longitudinal changes were found for genetic and environmental components of variance.