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Macular Pigment In Monozygotic Twins, Billy Randall Hammond

Doctoral Dissertations

Differences in the optical density of macular pigment between ten pairs of identical twins were examined. Foveal and parafoveal sensitivities to lights of 460 and 530 nm were measured by heterochromatic flicker photometry in five separate sessions for the right eye of each twin. These two wavelengths represent the maximum and minimum absorbance for macular pigment. Taking the difference in log sensitivity to the 460 nm light for the fovea and parafovea, after normalizing with respect to 530 nm, yields a measurement of the optical density of macular pigment. Statistically significant differences in macular pigment density were found for five …

Patterns Of Peer Relations And Adjustment: A Longitudinal Follow-Up Study, Mary Louise Hennessy Blum

Doctoral Dissertations

The risk hypothesis proposes that problematic peer relations predict later maladjustment. Extensive research on the risk hypothesis provides evidence that the quality of peer relations is associated with adjustment. The purpose of this dissertation was to examine the associations, concurrently and across time, among three distinct levels of peer relations (dyadic friendship, small group interactions, and sociometric status) and two perspectives of social/behavioral adjustment as assessed by parents and children. The study showed further support for the risk hypothesis that low peer group acceptance in the classroom, low prosocial non-interactions in the small group, low warmth and high conflict in …

The Effects Of Thalamic, Frontal Cortical And Hippocampal Formation Lesions On A Delayed Nonmatching To Sample Task, Heather Leslie Young

Doctoral Dissertations

Two areas of the brain have been implicated in global amnesia: the medial temporal lobe and the midline diencephalon (Squire and Zola-Morgan; Victor, Adams, and Collins, 1989). A third area of the brain, the prefrontal cortex, has more recently been included as a memory related area (Fuster, 1989).

The purpose of the study reported here was to further examine the neurological basis of the delayed nonmatching to sample place cue task (DNMTS-PC) deficit by comparing lesions in each of the three major areas attributed to memory processes. Patterns of impairments on the DNMTS-PC were further understood by manipulating retention and …

The Rhetoric Of Realism: American Psychology And American Literature, 1860-1910, Sandra Webster

Doctoral Dissertations

The period following the end of the Civil War in America and extending to just after the turn of the century witnessed the emergence of an independent discipline of psychology as well as the emergence of a uniquely American literary tradition. Though these developments occurred independently and operated out of different traditions, they shared a common interest in the concept of "consciousness." The present study is a comparison of models of consciousness expressed in psychological and literary texts of two periods: The first period covers the emergence of literary realism and American philosophical psychology (1865-1885); the second period covers literary …

Children Experiencing Unemployment Stress: A Comparison Of Families With Stable And Unstable Employment Histories, Barbara Alice Wauchope

Doctoral Dissertations

This study investigates children's experiences of changes that occur in families when fathers lose their jobs, the children's interpretations and responses to those changes, and their resulting symptoms of stress. In the first part, school-aged children and their parents in fourteen two-parent families in northern New England were interviewed and completed instruments measuring the children's behavior and symptoms of stress. In the second part, adults from seventy-six additional families completed a self-administered questionnaire. In both parts, children in families were divided into two groups and compared: middle-class with older parents in which fathers had little or no history of losing …