Altered resting-state functional connectivity of the anterior cingulate cortex in rats post noise exposure

Aims We aimed to find where and how noise-induced cochlear hearing loss affects the central nervous system during the early state and identify the neural substrate for aberrant patterns that mediating noise-related anxiety-/depression- like behaviors. Methods Broad band noise with 122 dB for 2 hours was conducted to induce hearing loss. We defined 0 day (N0D) and 10 days (N10D) post noise as the acute and sub-acute period. Behavioral tests (Open field test and light/dark test) and resting-state fMRI were computed to evaluate emotional conditions and aberrant neural activity. Functional connectivity analysis using the anterior cingulate cortex as a seed was computed to reveal the spatial distribution beyond auditory network during both periods. Results Anxiety-/depression-like behaviors were found in rats with noise exposure. Between-group analysis revealed that N0D rats displayed widespread reductions in functional connectivity, spanning primary somatosensory cortex, medial geniculate body, inferior colliculus, cingulate cortex, cerebellar lobule comparing with N10D rats and a similar pattern was also occurred in comparison with the control group. Conclusion Taken together, an acoustic-causing network accounting for distress and gating of noise exposure related anxiety/depression was proposed.

Automated summary

The study aimed to investigate the effects of noise-induced cochlear hearing loss on the central nervous system during the early stage and identify the neural substrate for aberrant patterns mediating noise-related anxiety/depression. Rats were exposed to broad band noise to induce hearing loss. Behavioral tests and resting-state fMRI were conducted to evaluate emotional conditions and aberrant neural activity. Functional connectivity analysis revealed widespread reductions in functional connectivity in rats with noise exposure compared to control groups, suggesting an acoustic-causing network for anxiety and depression related to noise exposure.