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Comparing Natural Travel With Artificial Travel Requirements In The Study Of Foraging In The Laboratory, Carlos Fernando Aparicio

Doctoral Dissertations

Is moving from place to place equivalent to pressing a lever or pecking a key? This dissertation addressed this question by comparing natural travel (moving from place to place) with artificial travel requirements (to press on a lever). In two experiments foraging was modeled with operant behavior. Rats "searched" for food by pressing on the left lever. The patch provided a maximum of 1, 2, or 8 pellets. When the patch provided 1 pellet, rats captured the first prey with a.10 probability. The probability dropped to zero after one pellet. When the patch provided 2 or 8 pellets rats captured …

A Comparison Of Methods For Analyzing Intraindividual Change In Student Epistemological Orientation During The Transition To College, Trey Michael Buchanan

Doctoral Dissertations

The ability to measure the development of epistemological beliefs of 235 college students during their first-semester in college was investigated by comparing the results obtained using five different methodological approaches to measuring change. These approaches included the use of the two-wave difference score, the residual change score, the cross-time correlation matrix, repeated measures analysis of variance, and individual growth modeling. A cubic individual growth model was found to be superior to other methods in describing intraindividual differences in dualistic epistemological orientation during the transition to college. An investigation of the existence of systematic interindividual differences in growth as a function …

Social Support, Psychological Distress And The Consequences Of Psychotherapeutic Intervention, David Francis King

Doctoral Dissertations

Several questions about social support and its relation to mental health over the course of psychotherapeutic intervention are investigated. These include: how do different measures of social support relate to each other at entrance to therapy (time 1) and three months later (time 2), how does social support vary with mental health over time, and how do strategies of therapists affect social support of patients?

Forty patients and their therapists (27) at two community mental health centers were interviewed. Four quantitative standardized measures of social support were used: Donald and Ware's social integration measure (1982), McFarlane's (1980) measure of social …

The Role Of Thalamo-Frontocortical Mechanisms In Measures Of Spatial Learning And Memory, Loredana Maggiora Harrison

Doctoral Dissertations

Human amnesia has been attributed to diencephalic lesions produced by Wernicke-Korsakoff syndrome, tumor, trauma and infarct. Rodent models of diencephalic amnesia suggest the involvement of three anatomic systems, namely the nuclei of the brainstem and diencephalon, the mammillary bodies, and the mediodorsal nucleus of the thalamus. In recent years our laboratory has investigated these systems. Only radiofrequency (RF) lesions of the thalamus involving lateral portions of the internal medullary lamina (L-IML) and including the mediodorsal nucleus (MDn) of the thalamus have disrupted measures of learning and memory in a manner that is qualitatively similar to that seen in human Korsakoff …

Intraindividual Consistencies In Psychophysical Judgment And The Psychophysical Function, Robin Elizabeth Daning

Doctoral Dissertations

Two issues are addressed: One is whether individual differences in psychophysical judgment reflect perceptual differences or differences in subjects' responses, and the second is whether the power law is adequate to describe the perceptions of individual subjects. Six subjects made cross-modal matches and difference matches using weight, finger span, and tone intensities. In order to minimize the chance of obtaining biased responses, number was not used, sessions were spaced far apart, a response continuum was used just once per session, and a set of criteria was adopted to select the best-fitting functions.

Difference matching data were subjected to a multidimensional …