Hypothalamic control of food intake may be overridden by cortical and limbic brain regions that process reward and the hedonic aspect of food, affecting the ability to discriminate between homeostatic and hedonic feeding. Women, in particular may be affected since cognition and perception of reward change during the menstrual cycle. Changes in estrogen and progesterone levels during the menstrual cycle induce changes in appetite and eating behavior. Food intake declines in the peri-ovulatory period when estrogen levels peak, but increases in the luteal phase when progesterone levels increase. In this novel study we introduce a different context in which to study appetite regulation; the menstrual cycle.
The two main study objectives were: 1) to compare the BOLD response between the peri-ovulatory and luteal phases of the menstrual cycle and 2) to compare the BOLD response between women in a negative and positive affect state in response to visual food stimuli using functional magnetic resonance imaging. Pictures of food, regardless of their caloric content stimulated greater activation during the follicular phase compared to the luteal phase in the orbitofrontal cortex, fusiform, amygdala and inferior operculum. Activity was present in the hippocampus, ventral tegmental area and nucleus accumbens in response to high calorie images but not low calorie images during the follicular phase. The insula showed selective activity responding to high calorie pictures in the luteal phase and low calorie pictures in the follicular phase.
High calorie food cues elicited greater BOLD signal for women reporting negative affect in the putamen, amygdala, pulvinar, prefrontal cortex, pallidum, fusiform and ventral tegmental area.
In summary, visual food cues produced a more robust response during the follicular phase of the menstrual cycle and during a negative mood state in brain regions modulating the rewarding and motivational effects of food images. An increased understanding of how appetite-regulating brain regions respond during the menstrual cycle and in different mood states may facilitate the development of new therapies to reduce the incidence of obesity. / Thesis (Master, Physiology) -- Queen's University, 2009-09-25 15:35:15.609
Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:OKQ.1974/5241 |
Date | 27 September 2009 |
Creators | Frank, TAMAR |
Contributors | Queen's University (Kingston, Ont.). Theses (Queen's University (Kingston, Ont.)) |
Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
Language | English, English |
Detected Language | English |
Type | Thesis |
Format | 4077521 bytes, application/pdf |
Rights | This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner. |
Relation | Canadian theses |
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