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Thesis (M.S.)--Oregon State University, 1978. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.

Auditory sensitivity has often been measured by identifying neural threshold in real-time (online) which can introduce bias in the audiograms that are produced. We tested this by recording auditory nerve activity of the notodontid moth Nadata gibbosa elicited by bat-like ultrasound and analysing the response offline. We compared this audiogram with a published online audiogram showing that the bias introduced can result in a difference in the audiogram shape. In the second part of our study we compared offline audiograms using spike number as threshold with others that used spike period and stimulus/spike latency, variables that have been suggested as providing behaviourally functional criteria. These comparisons reveal that functional audiograms are more flatly tuned than simple spike audiograms. The shapes of behavioural audiograms are discussed in the context of the selection pressure that maintains their shape, bat predation.

Auditory sensitivity has often been measured by identifying neural threshold in real-time (online) which can introduce bias in the audiograms that are produced. We tested this by recording auditory nerve activity of the notodontid moth Nadata gibbosa elicited by bat-like ultrasound and analysing the response offline. We compared this audiogram with a published online audiogram showing that the bias introduced can result in a difference in the audiogram shape. In the second part of our study we compared offline audiograms using spike number as threshold with others that used spike period and stimulus/spike latency, variables that have been suggested as providing behaviourally functional criteria. These comparisons reveal that functional audiograms are more flatly tuned than simple spike audiograms. The shapes of behavioural audiograms are discussed in the context of the selection pressure that maintains their shape, bat predation.

Thesis (Ph. D.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xi, 159 p. : ill., maps. Vita. Includes abstract. Includes bibliographical references.

Nitric oxide (NO) is a gaseous, unconventional chemical messenger suggested to play a fundamental role in olfaction. This thesis focuses on the role of NO in a primary olfactory center, the antennal lobe (AL) of the moth, Manduca sexta (M. sexta), to understand how NO affects olfactory-guided behavior. Studies in M. sexta report that NO is produced upon odor stimulation and has profound effects at the physiological level, but little is known about its significance to behavior. The central hypothesis examined in this thesis is that NO functions as a neuromodulator of olfactory-guided behavior in a circadian fashion. This hypothesis is examined in the following three studies: The first study questions whether basal levels of NO fluctuate with the light cycle. M. sexta are nocturnal animals that actively engage in odor-seeking behaviors at night. Using an NO sensor, NO concentrations were measured in the AL, optic lobe, and the remainder of the brain during subjective day and subjective night. NO concentrations are higher in the AL and optic lobes at night, suggesting that NO is likely involved in olfactory-guided behavior. The second inquiry focuses on developing a technique to manipulate NO levels in the AL and whether a specific behavior is affected. Using the proboscis extension reflex, olfactory conditioning is used to ask three questions: (1) does NO affect odor detection, (2) does NO affect discrimination between odorants, and (3) does NO affect learning and memory? Results indicate that NO affects short-term memory but does not affect odor detection, or discrimination between dissimilar odorants. The third inquiry examines the role of NO in memory and circadian time. It asks: (1) is there an optimal time of day for learning and memory, and (2) does the role of NO in memory change depending on the time of olfactory conditioning? Results indicate that NO in memory is modulated by circadian time. Taken together, these results suggest a unique functional role for NO in olfactory-guided behavior with two main conclusions: (1) NO modulates short-term memory in the AL, and (2) NO may be important for the circadian regulation of memory.

Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 174-189). Also available via the Internet.

Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains ix, 103 p. : ill. (some col.), col. maps. Includes abstract. Includes bibliographical references (p. 77-79).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1939. / Typescript. Includes abstract and vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 85-93).