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Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaves 141-171). Also available via the Internet.

This study examined the influence of experimentally induced mood change on the learning and recall of a list of pleasant and unpleasant daily events in young (18-35 years) and old (58-75 years) women. Mild mood changes were induced by having 166 subjects read emotionally descriptive accounts of tragic or uplifting life experiences. For half the subjects, the mood induction was presented before they learned a list describing 15 pleasant and 15 unpleasant daily events. For the remaining subjects, the mood induction occurred before they recalled the list. Baseline memory performance was assessed by having all subjects learn and recall one list in a neutral mood. Two dependent variables were used to look at mood induced changes in level (Total recall) and content (Affective Bias = Pleasant Events - Unpleasant events) of memory recall. Only the 128 subjects who met prespecified criteria for mood change were used in these analyses. Compared to performance in the neutral mood condition, significant mood content effects were observed only for negative moods induced at time of recall. Equivalent changes in affective bias were found across age groups, however, were due to increased recall of mood congruent memory items for the young, and decreased recall of mood incongruent memory items for the old. This mood content effect contributed to an overall decrease in total recall for old participants that was not found for young subjects. Because significant group differences in baseline memory performance were found between and within age groups, analysis of covariance was employed, using baseline memory performance as a covariate. No differences in the pattern of significant effects were found. Similarly, the use of pre-experimental mood, verbal ability, and affective response to the memory stimuli as covariates did not change the results, suggesting observed age differences in mood-induced memory change could not be attributed to these factors. These findings suggest that the locus of mood congruent memory selectivity occurs at time of retrieval. Mood-related memory cuing appears to be equally effective for young and old. The observed qualitative age differences in mood congruent memory were the reverse of the predicted pattern, however, it was suggested that more effective use of mood control strategies by the older women could have produced these effects. Results also suggest that the elderly may be more sensitive to the disruptive effects of negative mood on memory processing / Graduate

M.Phil. / Using newly developed statistical analysis methods for refractive error this study examines the difference between autorefraction and subjective refraction and how it is related to age. The term autorefractive excess refers to the amount obtained by subtracting the subjective refraction from the autorefraction. The clinical sample consisted of five groups of fifty subjects each. The subjects in group 1 ranged in age from 1 to 10 years, group 2 from 11 to 20 years, group 3 from 21 to 30 years, group 4 from 31 to 40 years and group 5 from 41 years and older. Only one examiner (the author) and one autorefractor (Allergan-Humphrey 580) were used. The study found that there was a difference between the mean autorefractive excesses for the different age groups and that the difference between autorefraction and subjective refraction was statistically significant in both the left and the right eyes of all age groups. Left and right eyes exhibited similar behavior. The autorefractive excess for both the left and the right eyes together of group 1 was approximately -0.25/-0.18 x180 in conventional and (-0.25 0.00 -0.43)' in h-notation. The autorefractive excess increases by approximately (0.10 0.00 0.10)' per decade. There is an astigmatic component of approximately -0.18 x180 in both eyes of all age groups. Approximately 60% of the subjects had sphere-equivalent strengths of autorefractive excesses of under 0.50 D. Therefore 60% of subjects might be content with a prescription given from the autorefractor reading. Approximately 50% of subjects had cylinderequivalent strengths of autorefractive excesses of under 0.50 D.

M.Phil. / The aim of this study was to use auto refraction to investigate both the short-term intra-ocular variation of refractive status among primary school children and the spread of refractive status across eyes. The sample consisted of 90 Caucasian school children from a primary school in a small town, Eloff, in the Mpumalanga province of South Africa ...

Research examining prospective memory and aging has grown enormously in last decade but many unanswered questions remain. Prospective memory refers to remembering what one intends to do and it can be contrasted to retrospective memory which refers to what one has done. Prospective memory has been studied as part of traditional memory systems but recent research suggests that it may be better understood as an executive function. Three studies were carried out to examine prospective memory in older adults while addressing the weaknesses of the previous research. In Study I, prospective memory tests and a battery of neuropsychological measures were administered to 129 healthy young-old and old-old adults. Study II examined the utility of the Prospective Memory Screening Questionnaire (PROMSQ) in a group of over 500 older adults, some of whom exhibited mild cognitive decline. A subset of this group also received a comprehensive neuropsychological battery. Study III included 80 healthy young-old and old-old adults. Along with a battery of neuropsychological measures, they were administered the Prospective Memory Test (PMT), a more comprehensive measure of prospective memory compared with the tasks administered in Study I. The analyses of Study I revealed age differences in favour of the younger adults on the event-based prospective memory tasks. Participants also remembered more information relating to the prospective memory component of the tasks than the retrospective memory component. In this study, measures of executive functioning accounted for more of the variance of the prospective memory tasks than the other cognitive functions, including retrospective memory. In Study III no age differences were observed for either time- or event-based prospective memory tasks. Performance on the PMT also was accounted for by measures of attention and executive functioning rather than the retrospective memory. A comprehensive error analysis on the PMT was also conducted. The results of Study II suggested that the PROMSQ may not be a good measure of self-reported prospective memory in older adults as the internal consistency of the measure was poor. Discussion focuses on the theoretical and practical implications of the results of the series of three studies. Possible reasons for the conflicting age results from previous research is addressed and related to the present findings. Finally, the strengths and weaknesses of the present series of studies the present series of studies discussed, as well as directions for future research. / Graduate

Recall of narrative content was studied in a sample of 170 children ranging from 5 to 11 years of age. Age range was divided into three equal intervals. The children within each interval were randomly assigned to four encoding conditions (symbolic, iconic, enactive, and symbolic-rehearsal) so that any effects of interactions between age-affected cognitive capacities and different encoding conditions could be gauged at 30 seconds and one week (after encoding). Between-ages (within condition) and between conditions (within age) comparisons revealed that age increase was generally, though not uniformly, accompanied by significant recall advantage. Analyses revealed that effects of different encoding conditions were sufficiently variable across the ages that age advantage was diminished when free recall performances of 5-7 year old children in enactive and iconic encoding conditions were compared to free recall performances of older children (9-11 years of age) in symbolic conditions of encoding. The results are discussed in relation to theoretical issues and educational questions. / Education, Faculty of / Educational and Counselling Psychology, and Special Education (ECPS), Department of / Graduate