The need for expedient detection of and response to signals of danger compels the development of sophisticated neural circuits for
threat processing. This threat neural circuitry should support not only identification of and response to innately threatening stimuli, but
also learning and memory of sensory cues predictive of such threats. While extensive rodent and human research has established an essential
role of the amygdala in processing innate and learned threats, increasing evidence suggests the existence of extra-amygdala neural circuits
that are capable of independent threat processing. The sensory cortex emerges as an important part of the threat circuitry, demonstrating
heightened neural response to innately threatening stimuli and persistent neural plasticity as a result of threat learning. In three separate
yet conceptually-integrated experiments, employing a combination of electrophysiological and functional magnetic resonance imaging (fMRI)
methods, this dissertation examines threat processing in the human sensory cortex, and importantly, disentangles its unique contribution from
that of the amygdala. Study 1 (Chapter 2) indicated that the ventral visual cortex was capable of fast, refined processing of threat scenes,
relatively independent of the amygdala. Studies 2 and 3 (Chapters 3 and 4) further applied threat conditioning to examine possible learning
and memory mechanisms by which the sensory cortex contributes to the processing of threat. Study 2 demonstrated immediate and long-term
plastic changes in the olfactory cortex to learned threat odors, combining fMRI, olfactory aversive conditioning, and a long-term memory
retention test (on Day 9). Lastly, Study 3 revealed visual cortical and amygdala contributions to immediate and lasting plastic changes to
learned visual threats, respectively, combining brain electrophysiology, visual aversive conditioning, and a long-term memory retention test
(on Day 16). Together, these three experiments demonstrate the critical role the sensory cortex plays in threat encoding and the origin of
such sensory cortical threat codes via associative learning. / A Dissertation submitted to the Department of Psychology in partial fulfillment of the requirements for the
degree of Doctor of Philosophy. / Fall Semester 2017. / September 20, 2017. / Fear conditioning, Long-term memory, Olfaction, Sensory cortex, Threat, Visual perception / Includes bibliographical references. / Wen Li, Professor Directing Dissertation; Mohamed Kabbaj, University Representative; Colleen M. Kelley,
Committee Member; Zuoxin Wang, Committee Member; Jian Feng, Committee Member.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_605040 |
| Contributors | You, Yuqi (author), Li, Wen (professor directing dissertation), Kabbaj, Mohamed (university representative), Kelley, Colleen M. (committee member), Wang, Zhi (committee member), Wang, Zuoxin (committee member), Feng, Jian (committee member), Florida State University (degree granting institution), College of Arts and Sciences (degree granting college), Department of Psychology (degree granting departmentdgg) |
| Publisher | Florida State University |
| Source Sets | Florida State University |
| Language | English, English |
| Detected Language | English |
| Type | Text, text, doctoral thesis |
| Format | 1 online resource (127 pages), computer, application/pdf |
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