Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

Thesis (M.A.)--University of Alberta, 1997. / In partial fulfilment of the requirements for the degree of Master of Arts, Faculty of Physical Education and Recreation. Also available online.

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

Theorists in organizational behavior have generally ignored emotional determinants of behavior. A task of this dissertation was to extend the use of emotions for understanding organizational behavior in general and work motivation in particular. Two theories, expectancy theory and network theory, are used to make predictions about the relationship between mood and perceptions of the relationship between effort and performance. According to expectancy theory, the effort that people choose to expend at tasks is a function of their belief about the degree to which effort and performance covary. Network theory predicts that memories are connected by a network of associations. The accessibility for recall of a memory is a function of the activation of these associations. In this way positive events are more accessible for recall when individuals are in a positive mood state because of associations based on the affective valence of memories. Such accessibility of events for recall has been shown to be a determinant of probability judgements. On this basis it was predicted that mood would bias individuals' judgements of the probability that specific levels of effort lead to specific levels of performance. In other words, that mood affects expectancy. Specifically, it was predicted that individuals in an elated mood would report higher expectancy than individuals in a depressed mood. Mood was defined as a self-evaluative feeling state. Two other hypotheses were formed: that mood would influence how cause for behavior is attributed, and that individual differences in self esteem would moderate the relationship between mood and expectancy. Three studies were performed to provide a foundation for the testing of these hypotheses. In a fourth study they were tested. Study One assessed the psychometric properties of measures of mood states, individual differences, and task perceptions. Study Two concerned the experimental induction of mood. Mood manipulations used in the experimental literature were reviewed and one, a musical procedure, was chosen. The validity of this manipulation was then tested by having participants listen to the music of an elated, neutral, or depressed mood induction procedure. The results of Study Two provided strong evidence for the validity of the manipulation. Both self-report measures of mood and an unobtrusive behavioral measure were significantly affected. The results of Study Two also showed the utility of a conceptualization of mood as comprising two components: arousal and pleasure. It was shown that depression is characterized by low arousal and displeasure, and elation by high arousal and pleasure. Study Three reviewed the conceptualization and measurement of expectancy. It was argued that expectancy is properly conceptualized as the perceived covariation between effort and performance. This requires measurement of the relationship between multiple levels of effort and multiple levels of performance and calculation from these measures of an index of perceived effort -- performance covariation. Most prior measurement has only considered the relationship between high effort and high performance. Further, it was argued that such appropriate measurement allows predictions to be made about expectancy across individuals, in contrast to the argument that expectancy theory is a within-subjects theory. Previous authors have used such an approach to measure expectancy but have not demonstrated its validity. Study Three undertook such validation. Participants completed one of two experimental tasks: one with high objective expectancy, the other with low objective expectancy. As predicted, scores on the perceived covariation measure of expectancy were significantly higher in the high objective expectancy task. Measures of related constructs were influenced in a manner consistent with this finding. It was concluded that strong support for the expectancy measure existed. On the foundation of Studies One, Two, and Three, Study Four undertook to test the formal hypotheses of the dissertation. In each of three experimental sessions, participants completed a business decision-making task, underwent either an elation, neutral mood, or depression induction procedure, and then completed measures of their mood state, expectancy, and other task perceptions. The results of Study Four indicated that significant differences in mood resulted from the manipulation. However, none of the experimental hypotheses were supported. Mood did not influence expectancy or task attributions. A number of alternate explanations for this finding were considered, including failure of the mood manipulation, measurement error, and lack of statistical power. Of these, it was concluded that while Study Four lacked power to detect a large effect, this did not fully explain the failure to support the experimental hypotheses. Also compelling was the argument that the mood manipulation was not sufficiently powerful. / Business, Sauder School of / Graduate

No description available.

Postpartum depression (PPD) remains a serious mood disorder without a known etiology. PPD has a prevalence of 7-15% in the general population. Women with a history of a mood disorder are at an even higher risk for the development of PPD. Work over the last few decades has established a strong association between circadian rhythm and sleep disturbances and mood disorders, such as Major Depressive Disorder (MDD) and Bipolar Disorder (BD). Despite the breadth of evidence associating circadian rhythm disruption and depressive mood episodes, literature establishing a connection between circadian rhythms and changes in mood across the perinatal period is lacking. The work outlined in this thesis aimed to address this gap by examining the association between circadian rhythm and sleep disturbances across the perinatal period and their association with changes in mood in women at high and low risk of PPD development. A total of 87 women were studied, 45 healthy controls and 42 women with a mood history. Women were interviewed during the third trimester of pregnancy and between six to twelve weeks postpartum. Sleep and circadian rhythms were measured using both subjectively with self-reported questionnaires and objectively with actigraphy. Our results show that women at high and low risk showed higher disruption differ in subjective circadian rhythmicity, as well as in both subjective and objective parameters of sleep. Specifically, women at high risk for postpartum were found to have lower sleep efficiency, as measured by actigraphy, in the postpartum. In addition, subjective and objective parameters of sleep and circadian rhythms are associated with changes in depressive symptoms across the perinatal period. Our findings suggest that stabilizing circadian rhythms and improving sleep quality throughout the perinatal period can prevent postpartum mood worsening, particularly for those women at greatest risk. / Thesis / Master of Science (MSc)

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