Early-Life Stress Impairs Perception and Neural Encoding of Rapid Signals in the Auditory Pathway

During developmental critical periods (CPs), early-life stress (ELS) induces cognitive deficits and alters neural circuitry in regions underlying learning, memory, and attention. Mechanisms underlying critical period plasticity are shared by sensory cortices and these higher neural regions, suggesting that sensory processing may also be vulnerable to ELS. In particular, the perception and auditory cortical (ACx) encoding of temporally-varying sounds both mature gradually, even into adolescence, providing an extended postnatal window of susceptibility. To examine the effects of ELS on temporal processing, we devel-oped a model of ELS in the Mongolian gerbil, a well-established model for auditory processing. In both male and female ani-mals, ELS induction impaired the behavioral detection of short gaps in sound, which are critical for speech perception. This was accompanied by reduced neural responses to gaps in auditory cortex, the auditory periphery, and auditory brainstem. ELS thus degrades the fidelity of sensory representations available to higher regions, and could contribute to well-known ELS-induced problems with cognition.

Automated summary

During developmental critical periods, early-life stress induces cognitive deficits and alters neural circuitry in regions underlying learning, memory, and attention. Sensory processing may also be vulnerable to early-life stress as mechanisms underlying critical period plasticity are shared by sensory cortices. In this study using Mongolian gerbils, early-life stress impaired the detection of short gaps in sound critical for speech perception, accompanied by reduced neural responses in auditory cortex, auditory periphery, and auditory brainstem. These findings suggest that early-life stress degrades sensory representations and could contribute to cognitive problems associated with early-life stress.