The Schröder staircase: A new perspective

A range of variants of the Schröder staircase was generated by computer, giving quantifiable changes of perspective and the option of adding appropriate texture to the steps of the staircase. Increases in perspective and the addition of texture gradients led to increases in the proportion of viewing time during which the percept appropriate to the perspective was reported. It is suggested that this might be a useful method of studying the processing of depth information.     

SELF-STIMULATION AND LEARNING IN AUTISTIC CHILDREN: PHYSICAL OR FUNCTIONAL INCOMPATIBILITY?1

This study investigated whether an observed inverse relationship between self-stimulation and learning in autistic children is due to a physical inability of the subject to use the same body part for self-stimulation and task responding, or whether self-stimulation “distracts” the subject from task responding. Four actively self-stimulating autistic children were taught two discrimination tasks; one required a response that physically interferred with their self-stimulation; the other did not. Results were: (a) all subjects responded similarly across both tasks; (b) the three subjects with higher mental age scores learned both tasks without external suppression of self-stimulation; and (c) none of the subjects showed an inverse relationship between self-stimulation and learning. The study demonstrated that elimination of self-stimulation is not a necessary prerequisite for the acquisition of a new behavior in all autistic children.     

Classifying pictures and words: Implications for the dual-coding hypothesis

In deciding that two items come from the same category, subjects were delayed if the items were presented as a word and a picture, as compared with two words or two pictures. Subjects were not delayed if the items were not to be compared. Hence, the delay appears to occur during the retrieval and comparison of know ledge about the items, not during their perceptual analysis. The results suggest that there are two distinct codes involved in the categorization of words and pictures, rather than a single code.     

Handling negative inputs: On the plausible equity formulae

Equity research has been based on defining formulae that do not necessarily imply the hypotheses thought to have been derived from them and that are not consistent with empirical data cited as supporting equity theory. Neither Adams' (1965) ratio definition nor Walster et al.'s (1970, 1972, 1973) formula satisfy the fundamental criterion that, when equity holds, outcome should be an increasing function of input. Six formulae that do satisfy this fundamental criterion (including Adams' ratio definition restricted to positive ratios, Walster et al.'s revision of their formula, three formulae generated by a simple constructive procedure, and an exponential definition) are compared with respect to 11 other criteria and with respect to their predictions of the results of two thought experiments.     

Fibromyalgia: the role of sleep in affect and in negative event reactivity and recovery

OBJECTIVE: Fibromyalgia (FM) syndrome is a chronic pain condition characterized by diffuse muscle pain, increased negative mood, and sleep disturbance. Until recently, sleep disturbance in persons with FM has been modeled as the result of the disease process or its associated pain. The current study examined sleep disturbance (i.e., sleep duration and sleep quality) as a predictor of daily affect, stress reactivity, and stress recovery. DESIGN AND MEASURES: A hybrid of daily diary and ecological momentary assessment methodology was used to evaluate the psychosocial functioning of 89 women with FM. Participants recorded numeric ratings of pain, fatigue, and positive and negative affect 3 times throughout the day for 30 consecutive days. At the end of each day, participants completed daily diary records of positive and negative life events. In addition, participants reported on their sleep duration and sleep quality each morning. RESULTS: After accounting for the effects of positive events, negative events, and pain on daily affect scores, it was found that sleep duration and quality were prospectively related to affect and fatigue. Furthermore, the effects of inadequate sleep on negative affect were cumulative. In addition, an inadequate amount of sleep prevented affective recovery from days with a high number of negative events. CONCLUSIONS: These results lend support to the hypothesis that sleep is a component of allostatic load and has an upstream role in daily functioning.