ABSTRACT
BLAST-INDUCED TINNITUS: A COMBINED BEHAVIORAL, MEMRE, AND ELECTROPHYSIOLOGY STUDY
by
JESSICA OUYANG
May 2014 Advisor: Drs. Steve Cala & Jinsheng Zhang
Major: Physiology
Degree: Doctor of Philosophy
Tinnitus and hearing loss are the frequent auditory-related co-morbidities of blast trauma. The etiology of blast-induced tinnitus is also muddled by brain mechanisms associated with emotional and cognitive problems such as anxiety, memory loss, and depression. We set out to develop a realistic and ecologically valid model to address changes of cognitive status and psychological state that are associated with blast- induced tinnitus. In this study, 19 adult rats were randomly divided into the sham group (n=6) and the blast group (n=13). Blast exposure (14 psi) was conducted via a shock wave tube to expose the left ears of the rats in the blast group, and a sham exposure was conducted to the rats in the sham group. Blast-induced tinnitus was evaluated with gap detection and pre-pulse inhibition (PPI) acoustic startle reflex paradigms; the changes of thresholds of the hearing was evaluated with auditory brainstem response (ABRs), the change in the level of anxiety was evaluated with elevated plus maze; and the change in the status of memory was evaluated with one-day Morris water maze. To investigate blast-induced neuronal changes in the limbic structures, we utilized MEMRI technique. Obtained with MRIcro, MR intensity signal-to-noise ratios (SNRs) of
83
selected limbic structures were measured to represent the level of synaptic activity. Of the 13 rats that were exposed to blast shock wave, 8 rats developed chronic tinnitus on post-exposure day 35 (PED35) and 5 rats did not. Our results showed that compared to rats in the sham group (n=6), (1) rats in the blast group with or without tinnitus demonstrated higher level of anxiety (p<0.05); (2) rats in the blast group that exhibited behavioral evidences of tinnitus (n=8) demonstrated neuronal hyperactivity in bilateral amygdaloidal complex, specifically bilateral basolateral groups and the left cortical-like group of the amygdala (p<0.05); and (3) rats in the blast group demonstrated neuronal hyperactivity in bilateral nucleus accumbens core (p<0.05). In conclusion, the elevated level of synaptic activity in the bilateral amygdala and nucleus accumbens core indicates central plasticity associated with blast-induced tinnitus.
","abstract_html":"<p>ABSTRACT</p> <p>BLAST-INDUCED TINNITUS: A COMBINED BEHAVIORAL, MEMRE, AND ELECTROPHYSIOLOGY STUDY</p> <p>by</p> <p>JESSICA OUYANG</p> <p>May 2014 Advisor: Drs. Steve Cala & Jinsheng Zhang</p> <p>Major: Physiology</p> <p>Degree: Doctor of Philosophy</p> <p>Tinnitus and hearing loss are the frequent auditory-related co-morbidities of blast trauma. The etiology of blast-induced tinnitus is also muddled by brain mechanisms associated with emotional and cognitive problems such as anxiety, memory loss, and depression. We set out to develop a realistic and ecologically valid model to address changes of cognitive status and psychological state that are associated with blast- induced tinnitus. In this study, 19 adult rats were randomly divided into the sham group (n=6) and the blast group (n=13). Blast exposure (14 psi) was conducted via a shock wave tube to expose the left ears of the rats in the blast group, and a sham exposure was conducted to the rats in the sham group. Blast-induced tinnitus was evaluated with gap detection and pre-pulse inhibition (PPI) acoustic startle reflex paradigms; the changes of thresholds of the hearing was evaluated with auditory brainstem response (ABRs), the change in the level of anxiety was evaluated with elevated plus maze; and the change in the status of memory was evaluated with one-day Morris water maze. To investigate blast-induced neuronal changes in the limbic structures, we utilized MEMRI technique. Obtained with MRIcro, MR intensity signal-to-noise ratios (SNRs) of</p> <p>83</p> <p>selected limbic structures were measured to represent the level of synaptic activity. Of the 13 rats that were exposed to blast shock wave, 8 rats developed chronic tinnitus on post-exposure day 35 (PED35) and 5 rats did not. Our results showed that compared to rats in the sham group (n=6), (1) rats in the blast group with or without tinnitus demonstrated higher level of anxiety (p<0.05); (2) rats in the blast group that exhibited behavioral evidences of tinnitus (n=8) demonstrated neuronal hyperactivity in bilateral amygdaloidal complex, specifically bilateral basolateral groups and the left cortical-like group of the amygdala (p<0.05); and (3) rats in the blast group demonstrated neuronal hyperactivity in bilateral nucleus accumbens core (p<0.05). In conclusion, the elevated level of synaptic activity in the bilateral amygdala and nucleus accumbens core indicates central plasticity associated with blast-induced tinnitus.</p>","abstract_has_math":false,"creators":["Ouyang, Jessica Pengyun"],"institution":null,"degree_name":"Ph.D.","degree_level":"Open Access Dissertation","degree_discipline":"Physiology","degree_department":null,"school":null,"contributors":["Jinsheng Zhang","Steven Cala"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014-01-01T08:00:00Z","date_published":"2014-01-01T08:00:00Z","updated_at":"2026-07-24T05:59:39Z","subjects":["Blast","coherence analysis","MEMRI","PTSD","Tinnitus","volatile anesthetics","Neurosciences","Physiology"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://digitalcommons.wayne.edu/oa_dissertations/910","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Jinsheng Zhang","Steven Cala"]},{"key":"dc:creator","label":"Author","values":["Ouyang, Jessica Pengyun"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2013-01-01T08:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Physiology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Open Access Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Blast","coherence analysis","MEMRI","PTSD","Tinnitus","volatile anesthetics","Neurosciences","Physiology"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://digitalcommons.wayne.edu/oa_dissertations/910"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["ABSTRACT
BLAST-INDUCED TINNITUS: A COMBINED BEHAVIORAL, MEMRE, AND ELECTROPHYSIOLOGY STUDY
by
JESSICA OUYANG
May 2014 Advisor: Drs. Steve Cala & Jinsheng Zhang
Major: Physiology
Degree: Doctor of Philosophy
Tinnitus and hearing loss are the frequent auditory-related co-morbidities of blast trauma. The etiology of blast-induced tinnitus is also muddled by brain mechanisms associated with emotional and cognitive problems such as anxiety, memory loss, and depression. We set out to develop a realistic and ecologically valid model to address changes of cognitive status and psychological state that are associated with blast- induced tinnitus. In this study, 19 adult rats were randomly divided into the sham group (n=6) and the blast group (n=13). Blast exposure (14 psi) was conducted via a shock wave tube to expose the left ears of the rats in the blast group, and a sham exposure was conducted to the rats in the sham group. Blast-induced tinnitus was evaluated with gap detection and pre-pulse inhibition (PPI) acoustic startle reflex paradigms; the changes of thresholds of the hearing was evaluated with auditory brainstem response (ABRs), the change in the level of anxiety was evaluated with elevated plus maze; and the change in the status of memory was evaluated with one-day Morris water maze. To investigate blast-induced neuronal changes in the limbic structures, we utilized MEMRI technique. Obtained with MRIcro, MR intensity signal-to-noise ratios (SNRs) of
83
selected limbic structures were measured to represent the level of synaptic activity. Of the 13 rats that were exposed to blast shock wave, 8 rats developed chronic tinnitus on post-exposure day 35 (PED35) and 5 rats did not. Our results showed that compared to rats in the sham group (n=6), (1) rats in the blast group with or without tinnitus demonstrated higher level of anxiety (p<0.05); (2) rats in the blast group that exhibited behavioral evidences of tinnitus (n=8) demonstrated neuronal hyperactivity in bilateral amygdaloidal complex, specifically bilateral basolateral groups and the left cortical-like group of the amygdala (p<0.05); and (3) rats in the blast group demonstrated neuronal hyperactivity in bilateral nucleus accumbens core (p<0.05). In conclusion, the elevated level of synaptic activity in the bilateral amygdala and nucleus accumbens core indicates central plasticity associated with blast-induced tinnitus.
"]},{"key":"dc:title","label":"Title","values":["Blast-Induced Tinnitus: A Combined Behavioral, Memri, And Electrophysiology Study"]}]}],"canonical_facts":{"dc:contributor":["Jinsheng Zhang","Steven Cala"],"dc:creator":["Ouyang, Jessica Pengyun"],"dc:date.available":["2013-01-01T08:00:00Z"],"dc:description.abstract":["ABSTRACT
BLAST-INDUCED TINNITUS: A COMBINED BEHAVIORAL, MEMRE, AND ELECTROPHYSIOLOGY STUDY
by
JESSICA OUYANG
May 2014 Advisor: Drs. Steve Cala & Jinsheng Zhang
Major: Physiology
Degree: Doctor of Philosophy
Tinnitus and hearing loss are the frequent auditory-related co-morbidities of blast trauma. The etiology of blast-induced tinnitus is also muddled by brain mechanisms associated with emotional and cognitive problems such as anxiety, memory loss, and depression. We set out to develop a realistic and ecologically valid model to address changes of cognitive status and psychological state that are associated with blast- induced tinnitus. In this study, 19 adult rats were randomly divided into the sham group (n=6) and the blast group (n=13). Blast exposure (14 psi) was conducted via a shock wave tube to expose the left ears of the rats in the blast group, and a sham exposure was conducted to the rats in the sham group. Blast-induced tinnitus was evaluated with gap detection and pre-pulse inhibition (PPI) acoustic startle reflex paradigms; the changes of thresholds of the hearing was evaluated with auditory brainstem response (ABRs), the change in the level of anxiety was evaluated with elevated plus maze; and the change in the status of memory was evaluated with one-day Morris water maze. To investigate blast-induced neuronal changes in the limbic structures, we utilized MEMRI technique. Obtained with MRIcro, MR intensity signal-to-noise ratios (SNRs) of
83
selected limbic structures were measured to represent the level of synaptic activity. Of the 13 rats that were exposed to blast shock wave, 8 rats developed chronic tinnitus on post-exposure day 35 (PED35) and 5 rats did not. Our results showed that compared to rats in the sham group (n=6), (1) rats in the blast group with or without tinnitus demonstrated higher level of anxiety (p<0.05); (2) rats in the blast group that exhibited behavioral evidences of tinnitus (n=8) demonstrated neuronal hyperactivity in bilateral amygdaloidal complex, specifically bilateral basolateral groups and the left cortical-like group of the amygdala (p<0.05); and (3) rats in the blast group demonstrated neuronal hyperactivity in bilateral nucleus accumbens core (p<0.05). In conclusion, the elevated level of synaptic activity in the bilateral amygdala and nucleus accumbens core indicates central plasticity associated with blast-induced tinnitus.
"],"dc:identifier":["https://digitalcommons.wayne.edu/oa_dissertations/910"],"dc:subject":["Blast","coherence analysis","MEMRI","PTSD","Tinnitus","volatile anesthetics","Neurosciences","Physiology"],"dc:title":["Blast-Induced Tinnitus: A Combined Behavioral, Memri, And Electrophysiology Study"],"thesis:degree_discipline":["Physiology"],"thesis:degree_level":["Open Access Dissertation"],"thesis:degree_name":["Ph.D."]},"updated_at":"2026-07-24T05:59:39Z"}