Early emergence for thermal processing in the neonatal somatosensory cortex and its perturbation in ASD

Thermal perception is essential for neonatal adaptation and survival, yet the cortical processing during early development remains unknown. Here we show that non-painful cool, but not warm, orofacial stimulation evokes robust and lateralized activation in the whisker-related somatosensory cortex (wS1) of neonatal mice during the first postnatal week. These responses, revealed by mesoscopic in vivo imaging and electrophysiological recordings, partly overlap with tactile representations from the same region, indicating early regionalization of thermotactile maps. In a mouse model of autism spectrum disorder deficient for Magel2, we found altered spatial encoding of cool stimuli accompanied by increased local field potential activity, suggestive of cortical hyperexcitability. Our findings establish that the cortical processing of cool sensory information emerges from the first week of life and is disrupted in a genetic model of autism, highlighting early vulnerability of thermosensory circuits and their potential contributions to neurodevelopmental disorders.