Auditory decision-making deficits after permanent noise-induced hearing loss

Area of Science:

• Neuroscience
• Auditory Neuroscience
• Cognitive Neuroscience

Background:

• Loud noise exposure is a primary cause of permanent hearing loss.
• Noise-induced hearing loss (NIHL) is linked to deficits in speech comprehension and cognitive functions like attention and decision-making.

Purpose of the Study:

• To investigate if noise-induced hearing loss (NIHL) directly impairs auditory cognitive function.
• To assess the impact of NIHL on auditory decision-making performance in gerbils.

Main Methods:

• Gerbils were trained on an auditory decision-making task distinguishing between slow and fast amplitude-modulated (AM) noise presentation rates.
• Noise-induced hearing loss (NIHL) was induced via a single exposure to loud broadband noise (120 dB SPL).
• Decision-making task performance and auditory brainstem responses (ABRs) were evaluated pre- and post-NIHL.

Main Results:

• Noise-induced hearing loss (NIHL) resulted in permanent hearing loss, evidenced by elevated ABR threshold shifts.
• Following NIHL, gerbils exhibited diminished perceptual acuity, reduced attentional focus, altered choice bias, and slower evidence accumulation during auditory decision-making.
• NIHL also impacted sensory-guided, decision-based motor execution, as shown by video-tracking analysis.

Conclusions:

• Noise-induced hearing loss (NIHL) directly impairs auditory cognitive function.
• NIHL affects sensory, cognitive, and motor processes essential for auditory decision-making.
• These findings highlight the broad impact of hearing loss beyond auditory perception.