Changes in Prefrontal Cortex–Thalamic Circuitry after Acoustic Trauma

Barry, Kristin M. and Robertson, Donald and Mulders, Wilhelmina H. A. M. (2021) Changes in Prefrontal Cortex–Thalamic Circuitry after Acoustic Trauma. Biomedicines, 9 (1). p. 77. ISSN 2227-9059

[thumbnail of biomedicines-09-00077-v2.pdf] Text
biomedicines-09-00077-v2.pdf - Published Version

Download (847kB)

Abstract

In the adult auditory system, loss of input resulting from peripheral deafferentation is well known to lead to plasticity in the central nervous system, manifested as reorganization of cortical maps and altered activity throughout the central auditory pathways. The auditory system also has strong afferent and efferent connections with cortico-limbic circuitry including the prefrontal cortex and the question arises whether this circuitry is also affected by loss of peripheral input. Recent studies in our laboratory showed that PFC activation can modulate activity of the auditory thalamus or medial geniculate nucleus (MGN) in normal hearing rats. In addition, we have shown in rats that cochlear trauma resulted in altered spontaneous burst firing in MGN. However, whether the PFC influence on MGN is changed after cochlear trauma is unknown. We investigated the effects of electrical stimulation of PFC on single neuron activity in the MGN in anaesthetized Wistar rats 2 weeks after acoustic trauma or sham surgery. Electrical stimulation of PFC showed a variety of effects in MGN neurons both in sham and acoustic trauma groups but inhibitory responses were significantly larger in the acoustic trauma animals. These results suggest an alteration in functional connectivity between PFC and MGN after cochlear trauma. This change may be a compensatory mechanism increasing sensory gating after the development of altered spontaneous activity in MGN, to prevent altered activity reaching the cortex and conscious perception.

Item Type: Article
Uncontrolled Keywords: acoustic trauma; medial geniculate nucleus; prefrontal cortex; electrophysiology
Subjects: STM Repository > Biological Science
Depositing User: Managing Editor
Date Deposited: 24 Feb 2023 06:00
Last Modified: 02 Oct 2024 08:07
URI: http://classical.goforpromo.com/id/eprint/1010

Actions (login required)

View Item
View Item