University of Strathclyde website
Digital Collections - University of Strathclyde Library
Search Results Previous Searches E-Shelf
Login End Session
Search 'System Number= 000004022' in 'General Silo' Collection [ Sorted by: Name/Title ] Refine search
Table view Full view
Record 1 of 1 1
Add to E-Shelf
e-item icon
PDF of thesis T14065 PDF of thesis T14065 - (7 M)
Title Functional laminar architecture of rat primary auditory cortex following acoustic trauma / Tansi Jamshed Khodai.
Name Khodai, Tansi Jamshed. .
Abstract Exposure to loud sound can cause a series of hearing problems, the most common being tinnitus or hearing loss (temporary or permanent). Furthermore, tinnitus caused due to acoustic trauma may be observed with or without hearing loss, making it harder for tinnitus researchers to understand the pathology of this condition. Despite extensive studies in both animal and human subjects, it is still not fully understood how acoustic trauma can change neuronal activity in the auditory cortex. Several animal studies suggest changes in auditory tuning properties and increase in spontaneous activity after exposure to acoustic trauma. However, there are several discrepancies in observed changes. One possible explanation for this could be that these findings represent an average response across cortical depths which could mask the layer specific alteration in neural activity following acoustic trauma because previous studies have shown laminar specific evoked and spontaneous activity. In this study we tested the hypothesis that acoustic trauma alters neural activity in a layer-specific manner. Rats were anesthetised with urethane anaesthesia and recordings were obtained using multichannel linear silicon probes inserted vertically into the primary auditory cortex. The animals were exposed (bilaterally) to one octave white noise centred at 16 kHz, at 110 dB SPL for 1 hour. Spontaneous and auditory-evoked activity was measured before trauma and then one and two hour time-points after the acoustic trauma. We quantified laminar specific and average changes in different tuning curve parameters such as threshold, characteristic frequency, bandwidth, sparseness, spontaneous firing rate and burst like activity after trauma exposure in three different frequency regions of primary auditory cortex.
Abstract We observed laminar-specific changes in auditory tuning properties such as increase in threshold and spontaneous activity mainly in layer V of the primary auditory cortex following acoustic trauma. Furthermore, we also observed increase in burst-like spiking in the superficial layers. These findings support the hypothesis that acute effects of acoustic trauma on auditory cortical population activity is laminar-specific. These findings provide essential information regarding the changes in circuit mechanisms that develop following acoustic trauma which are critical for enhancing our knowledge about the pathology of these conditions and also to identify new potential targets to treat them.
Publication date 2014.
Name University of Strathclyde. Strathclyde Institute of Pharmacy and Biomedical Sciences.
Thesis note Thesis Ph. D University of Strathclyde 2014 T14065

Powered by Digitool Contact us Electronic Library Services Library Home