Abstract not available.

Abstract not available.

Abstract not available.

Abstract not available.

The apparently simple decision to initiate or terminate a meal is extremely complex. However, the need to determine the physiological and psychological mechanisms regulating these processes has taken on an air of urgency due to escalating levels of eating disorders in our society. Ingestive patterns are influenced by a number of factors, including signaling circuits utilizing peptides, such as corticotropin-releasing hormone (CRH) and bombesin-like peptides (BN-LPs). As some of the peptidergic systems under study have also been implicated in the mediation of the stress response, some peptidergic linkages between 'stress' and 'satiety' responses are also explored. The overall objective of this thesis was to examine the pattern of utilization or release of BN-LPs and CRH at specific brain loci during (1) various phases of food ingestion, (2) the presentation of anticipatory cues paired with an appetitive event, and (3) exposure to stressors. Using in vivo microdialysis, we demonstrated that both CRH and BN-LPs are released from the central nucleus of the amygdala in response to both restraint stressor exposure and spontaneous food ingestion, an effect that was mirrored at the anterior pituitary. Furthermore, we demonstrated that CRH and BN-LPs were released at the medial prefrontal cortex in response to the "anticipation" of a palatable snack. These results raised the intriguing possibility that some aspects of both the feeding behavior and the organism's response to stressor exposure are being subserved by a common neurochemical mechanism(s). As such, it would be expected that variables that affect an organism's stress response would also have an impact on feeding behavior and related neurochemical processes. In fact we found that early life experience, gender and genetics variables (that appear to impact the stress response) also impact on the animal's neurochemical response(s) to ingestion as well as their propensity to consume a palatable snack. These experiments extend our current knowledge of the mechanism(s) underlying the control of food intake and support our contention that these systems may also serve to draw attention to events or cues of biological salience. Finally, these results also provide new insights into the potential mechanism(s) underlying various stress and eating dysfunctions, including anorexia nervosa, anorexia associated with AIDS, cancer, sickness or stress, bulimia nervosa, obesity and depression.

Positive states of mind and emotion are essential to skilled golf performance, yet the substance of these desirable capacities has received minimal attention. The aim of the present study, therefore, was to investigate the preperformance thoughts of expert golfers during their play in a tournament round, in order to determine the states of mind and emotion that these golfers experienced, and to examine the relationship of this mental and emotional activity to subsequent golf performance. Each of seven male amateur golfers who play Quebec Golf Association and Royal Canadian Golf Association events (average handicap 0), was videotaped on a separate tournament day. Following the round, each participant was interviewed, whereby he was asked to recall what he was attempting to do, what he was thinking and feeling. The videotape was then played back to stimulate further input. Inductive analyses of interview transcripts disclosed that the preperformance thoughts expressed by the participants fell into two main dimensions: Thoughts of a positive nature were associated with successful shot outcomes, and described effective mental preparation skills, effective technical/tactical strategies, and positive feeling states. Thoughts with clearly negative overtones were associated with unsuccessful outcomes, and pertained to ineffective mental preparation, technical/tactical weaknesses, and negative feeling states. The stimulated recall interviews were successful in garnering the content of the participants' thoughts, and was a methodological strategy which had not yet been used in golf. The participants found the process helpful in that it enhanced their awareness about many facets of their play, which frequently translated into improved play in subsequent rounds. The information gleaned from this study will likely aid other golfers who wish to improve their attentional skills, and the procedure used is an innovative manner in which to initiate consulting interactions.

No description available.

Many animals appear to have a sophisticated spatial representation of their environment (i.e., a map). The development of these maps depends on the joint abilities of discriminating novel objects and remembering their locations. Variations of a detection of novelty paradigm were used to determine the nature and limitations of mapping skills in rhesus monkeys. Socially-housed monkeys in three different settings (indoor pens--UMASS, indoor/outdoor cages--NERPRC, outdoor enclosure--NIHAC) were exposed to mapping simulations using a vertical object grid arranged on a mesh wall of the animals' pens. In most cases, monkeys rapidly responded with increased exploration to the replacement of one familiar object with a novel object, to the movement of a familiar object to a novel location, and to the swapping of two familiar objects. However, novelty of object was more salient than novelty of place. In these initial studies, monkeys were given continuous access to the grid, and only one or two changes occurred on a given day. In subsequent studies, the task difficulty was varied either by reducing the length of grid exposure or increasing the number of changed objects/session. Surprisingly, only a reduction in length of exposure markedly affected mapping abilities. The variables of age and object experience had a greater affect on the accuracy of the mapping system when the memory requirements of the task were increased, as in the latter studies. Individuals varied substantially in their responses to novelty. This may be due to factors such as the nature of the objects or the choice of tactile/oral manipulation as the dependent variable. This result suggested that the mapping abilities of rhesus monkeys were underestimated. Rhesus monkeys clearly possessed misplace mapping abilities. These abilities were negatively affected only when monkeys' access to the grid was limited. The procedure employed here provided a convenient way to assess complex cognitive abilities in a group setting, It also relied on rhesus monkeys' inherent attraction to novelty and required only their species-typical behavior for assessment.

Hormonal control of developmental cell death is the best-established mechanism of neural sexual differentiation. For example, the spinal nucleus of the bulbocavemosus (SNB) is a sexually-dimorphic cluster of motoneurons in the lumbar spinal cord that innervates perineal muscles. Testosterone acts during a perinatal critical period to reduce cell death, and as a result, male rodents have more and larger SNB motoneurons than do females. Conversely, testosterone increases cell death in the anteroventral penventricular nucleus (AVPV), making it larger in females than in males. The Bcl-2 family of proteins has been implicated in mediating developmentally-regulated cell death. The ratio of pro-life (e.g., Bcl-2) to pro-death (e.g., Bax) family members apparently determines a cell's fate. We found that Bcl-2 overexpression increased neuron number in the SNB of females and in the AVPV of males. By contrast, Bcl-2 overexpression increased cell number equally in both sexes in the retrodorsolateral nucleus (RDLN), a spinal nucleus in which cell number is neither sexually dimorphic nor affected by perinatal hormone treatments. An immunocytochemical analysis indicated that Bcl-2, Bcl-xL and Bax are normally present in SNB motoneurons during the perinatal critical period, although their role in mediating SNB apoptosis is unclear. In adulthood, testosterone no longer determines SNB motoneuron survival, but does regulate soma size and dendritic extent. The continued expression of Bcl-2 family members in some neurons after the cell death period suggests additional roles beyond the regulation of cell death. I found that castration of adult male rats reduced Bcl-2 immunoreactivity in SNB motoneurons, and this reduction could be prevented by testosterone; Bax expression was not affected. Although the adult plasticity of SNB motoneurons is well characterized in rats, it has not been elucidated in mice. Four weeks following castration, soma size and dendritic extent shrink in rat SNB motoneurons. However, we showed that in the B6D2F1 strain of mouse, soma size decreased 6 and 12 weeks following castration, but dendritic extent remained unchanged. In addition, although Bcl-2 appears to be regulated by testosterone in the SNB motoneurons of adult rats, overexpression of Bcl-2 could not compensate for castration-induced soma size changes in the mouse SNB.

My dissertation focuses on how the brain encodes a learned motor sequence. I look at the encoding of birdsong in the zebra finch (Taeniopygia guttata) to understand the mechanisms that underlie motor encoding. Juvenile zebra finches learn their songs by imitating the song of an adult tutor. The motor memory for song is encoded within HVC (acronym is name), a premotor nucleus within the avian cortical pathway that generates vocal-motor output. When I began my research, the synaptic architecture of HVC was thought to be uniform and non-topographic. In turn, the encoding of song was thought to be evenly distributed across this non-topographic synaptic architecture. However, the evidence for these views was incomplete, particularly with respect to the intrinsic connectivity of HVC, which had never been tested. I began my research with a tract-tracing experiment to test for a non-topographic pattern of intrinsic connectivity among HVC neurons. I found a highly topographic pattern of intrinsic connectivity – HVC neurons connect preferentially along the rostral-caudal axis, forming numerous parallel "swaths" of neurons aligned to the rostral-caudal axis of HVC. This organization suggested a potential parallel organization within the rest of the cortical pathway, which I subsequently confirmed: connectivity within the entire cortical pathway is massively parallel in terms of afferent (input) connectivity, intrinsic connectivity, and efferent (output) connectivity. If this parallel connectivity encodes the different spectral and/or temporal aspects of song in parallel, I hypothesized that parallel connectivity may emerge as a function of song learning. To test this hypothesis, I developed a surgical manipulation to attenuate juvenile learning (disconnection of the avian basal ganglia). I found that attenuated song learning results in a loss of parallel input connectivity within the rostral-caudal axis of HVC. Overall, my results provide an anatomical basis for the parallel encoding of song, and further suggest that this parallel organization develops as a function of song learning. / A Dissertation submitted to the Department of Psychology in partial fulfillment of the Doctor of Philosophy. / Spring Semester 2016. / March 29, 2016. / Anatomy, Behavior, Development, Neuroethology, Songbird, Zebra finch / Includes bibliographical references. / Frank Johnson, Professor Directing Dissertation; Richard Morris, University Representative; Richard Hyson, Committee Member; Anders Ericsson, Committee Member; Wei Wu, Committee Member; Richard Bertram, Committee Member.