In recent years increasing interest has centered on the elderly psychogeriatric patient living in the community and the part played by relatives in supporting these patients. There is a need, however, for ways of assessing the behavioural disturbance shown by such patients at home and the effect this behaviour has on relatives. Ratings by relatives of the behaviour at home of elderly dementing patients attending a geriatric psychiatry day hospital, together with the relatives' own ratings of the degree of stress and upset being experienced were obtained. Using the technique of factor analysis was shown that the patient's behaviour and the relative's reaction could be analysed into a number of separate categories and that these were differentially related to each other. Thus, for example, personal distress in the relative was related mainly to the amount of apathetic and withdrawn behaviour shown by the patient, whereas negative feelings held by the relative towards the patient were related only to the degree of disturbance of the patient's mood. The construction of scales measuring these different aspects of patient's behaviour and relative's reaction is described.

We consider the Monte Carlo problem of generating points uniformly distributed within an arbitrary bounded (measurable) region. The class of Markovian methods considered generate points asymptotically uniformly distributed within the region. Computational experience suggests the methods are potentially superior to conventional rejection techniques for large dimensional regions.

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A systematic investigation of the subjective magnitude of vibrotaction was undertaken to: (1)

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Hit-and-Run algorithms are Monte Carlo procedures for generating points that are asymptotically distributed according to general absolutely continuous target distributions G over open bounded regions S. Applications include nonredundant constraint identification, global optimization, and Monte Carlo integration. These algorithms are reversible random walks which commonly apply uniformly distributed step directions. We investigate nonuniform direction choice and show that under minimal restrictions on the region S and target distribution G, there exists a unique direction choice distribution, characterized by necessary and sufficient conditions depending on S and G, which optimizes a bound on the rate of convergence. We provide computational results demonstrating greatly accelerated convergence for this optimizing direction choice and for more easily implemented adaptive heuristic rules.

Results are reviewed concerning some effects, at a units's characteristic frequency, of a short-term conditioning stimulus on the responses to perstimulatory and poststimulatory test tones. A phenomenological equation is developed from the poststimulatory results and shown to be consistent with the perstimulatory results. According to the results and equation, the response to a test tone equals the unconditioned or unadapted response minus the decrement produced by adaptation to the conditioning tone. Furthermore, the decrement is proportional to the driven response to the conditioning tone and does not depend on sound intensity per se. The equation has a simple interpretation in terms of two processes in cascade--a static saturating nonlinearity followed by additive adaptation. Results are presented to show that this functional model is sufficient to account for the "physiological masking" produced by wide-band backgrounds. According to this interpretation, a sufficiently intense background produces saturation. Consequently, a superimposed test tone cause no change in response. In addition, when the onset of the background precedes the onset of the test tone, the total firing rate is reduced by adaptation. Evidence is reviewed concerning the possible correspondence between the variables in the model and intracellular events in the auditory periphery.