Resting Neural Activity Patterns in Auditory Brain Areas following Conductive Hearing Loss

Conductive hearing loss (otitis media) in young children can effect speech and language development. However, little is known about the effects of conductive loss on neural activity in the auditory system. Hypothesis: Conductive hearing loss will change resting activity levels at the inner hair cell synapse, and lead to auditory deprivation of central auditory pathways. A conductive loss was produced by blocking the ear canals in mice. Resting neural activity patterns were quantified in brainstem and midbrain using c-fos immuno-labelling. Experimental subjects were compared to normal hearing controls and subjects with cochlear ablation. Conductive loss subjects showed a trend in reduction in c-fos labelled cells in cochlear nucleus and the central nucleus of inferior colliculus compared to normal controls. Results seen in this study may indicate the influence of conductive hearing loss on the developing auditory brain during early postnatal years when the system is highly plastic.MAS