PT  - JOURNAL ARTICLE
AU  - Kelsey L. Anbuhl
AU  - Justin D. Yao
AU  - Robert A. Hotz
AU  - Todd M. Mowery
AU  - Dan H. Sanes
TI  - Auditory processing remains sensitive to environmental experience during adolescence
AID  - 10.1101/2021.04.12.439537
DP  - 2021 Jan 01
TA  - bioRxiv
PG  - 2021.04.12.439537
4099  - http://biorxiv.org/content/early/2021/04/14/2021.04.12.439537.short
4100  - http://biorxiv.org/content/early/2021/04/14/2021.04.12.439537.full
AB  - Development is a time of great opportunity. A heightened period of neural plasticity contributes to dramatic improvements in perceptual, motor, and cognitive skills. However, developmental plasticity poses a risk: greater malleability of neural circuits exposes them to environmental factors that may impede behavioral maturation. While these risks are well-established prior to sexual maturity (i.e., critical periods), the degree of neural vulnerability during adolescence remains uncertain. To address this question, we induced a transient period of hearing loss (HL) spanning adolescence in the gerbil, confirmed by assessment of circulating sex hormones, and asked whether behavioral and neural deficits are diminished. Wireless recordings were obtained from auditory cortex neurons during perceptual task performance, and within-session behavioral and neural sensitivity were compared. We found that a transient period of adolescent HL caused a significant perceptual deficit (i.e., amplitude modulation detection thresholds) that could be attributed to degraded auditory cortex processing, as confirmed with both single neuron and population-level analyses. To determine whether degraded auditory cortex encoding was attributable to an intrinsic change, we obtained auditory cortex brain slices from adolescent HL animals, and recorded synaptic and discharge properties from auditory cortex pyramidal neurons. There was a clear and novel phenotype, distinct from critical period HL: excitatory postsynaptic potential amplitudes were elevated in adolescent HL animals, whereas inhibitory postsynaptic potentials were unchanged. This is in contrast to critical period deprivation, where there are large changes to synaptic inhibition. Taken together, these results show that sensory perturbations suffered during adolescence can cause long-lasting behavioral deficits that originate, in part, with a dysfunctional cortical circuit.Summary of experimental design and main findings.Competing Interest StatementThe authors have declared no competing interest.(AC)auditory cortex(HL)hearing loss(AM)amplitude modulation(IPSP)inhibitory postsynaptic potential(EPSP)excitatory postsynaptic potential