Pairing with Enriched Sound Exposure Restores Auditory Processing Degraded by an Antidepressant

Area of Science:

• Neuroscience
• Pharmacology
• Auditory Processing

Background:

• Antidepressants are crucial for treating depression and anxiety.
• However, they can negatively impact sensory processing, particularly hearing, potentially worsening psychiatric symptoms.
• The mechanisms behind these auditory deficits remain unclear.

Purpose of the Study:

• To investigate how antidepressants, specifically fluoxetine, affect auditory processing.
• To explore the underlying neurobiological changes associated with these deficits.
• To identify potential strategies for mitigating antidepressant-induced auditory impairments.

Main Methods:

• Adult female rats were treated with fluoxetine and assessed on a tone-frequency discrimination task.
• Cortical neuronal responses to sound frequencies were analyzed.
• Perineuronal net expression and plasticity in the auditory cortex were examined.
• Rats were exposed to an enriched acoustic environment post-treatment.

Main Results:

• Fluoxetine-treated rats showed impaired auditory discrimination and reduced cortical neuronal selectivity.
• Decreased perineuronal nets, especially around inhibitory interneurons, were observed.
• Fluoxetine induced plasticity in mature auditory cortices.
• Enriched acoustic environment exposure reversed behavioral and cortical processing deficits and normalized perineuronal net expression.

Conclusions:

• Antidepressants can degrade auditory processing by reducing intracortical inhibition.
• This degradation is linked to changes in perineuronal nets and induced cortical plasticity.
• Combining antidepressant treatment with enriched sound exposure can alleviate auditory processing deficits.
• These findings suggest new therapeutic avenues for psychiatric disorders.