A new study sheds light on how early life stress (ELS) can cause long-lasting damage to the brain’s ability to process sound—and how a timed acoustic intervention might reverse those effects. Published recently in the Journal of Neuroscience, the research studies how maternal separation (MS), a widely used model of ELS in rodents, alters both behavior and cortical processing related to auditory spatial perception.
In the study, institute faculty Professor Xiaoming Zhou and his team exposed newborn rats to daily MS during a critical developmental window. As adults, these rats showed significant impairments in sound-azimuth discrimination—the ability to locate where a sound is coming from. Neurophysiological recordings revealed that neurons in the auditory cortex of these rats had broadened azimuth tuning, meaning they responded less precisely to spatial cues in sound. Further analyses showed that these neurons had fewer dendritic branches and reduced spine density—structural features critical for processing complex sound inputs.
Crucially, the study found that exposing the MS rats to an enriched acoustic environment (EAE) during the early stress period protected them from these negative effects. Animals reared under EAE conditions not only performed normally in sound localization tasks but also retained intact cortical tuning and neuronal structure. This suggests that sensory enrichment can buffer the brain against the damaging consequences of early adversity.
These findings highlight the vulnerability of sensory systems to early stress and point to auditory enrichment as a promising, non-invasive intervention for mitigating sensory and cognitive deficits associated with ELS.
Journal Reference
An, O., Fang, Y., Cheng, Y., Liu, H., Yang, W., Shan, Y., de Villers-Sidani, E., Zhang, G.*, & Zhou, X.* (2025). Acoustic Enrichment Prevents Early Life Stress-Induced Disruptions in Sound Azimuth Processing. Journal of Neuroscience, 45 (18) e2287242025.
>> To read the article in Chinese at the School of Life Sciences, East China Normal University, click here.