Specific and Nonuniform Brain States during Cold Perception in Mice

Area of Science:

• Neuroscience
• Sensory Processing
• Thermoregulation

Background:

• Supraspinal mechanisms integrating thermal information are complex and not fully understood.
• The dorsal horn of the spinal cord initiates thermal encoding, transmitting signals via spinothalamic and thalamocortical pathways.
• Limited knowledge exists on brain region interplay during thermal processing.

Purpose of the Study:

• To investigate the interplay between brain regions during thermal processing using advanced imaging techniques.
• To elucidate the central nervous system's response to varying thermal stimuli.
• To identify novel functional networks involved in temperature perception.

Main Methods:

• Functional ultrasound imaging was employed in adult awake male mice.
• Brain activity was recorded during plantar exposure to constant and varying temperatures.
• Resting-state brain imaging was performed to capture baseline neural activity.

Main Results:

• A novel dichotomy was observed between somatomotor-cingulate cortices and the hypothalamus in response to temperature.
• Colder temperatures (ramped down) induced a disconnection between somatomotor-cingulate and hypothalamus networks.
• Cingulate areas are inferred to play a role in affective responses to temperature.
• A brain mode with low cognitive strength was confirmed in mice, prevalent at neutral temperatures.

Conclusions:

• The study identifies a common neural hub between somatomotor and cingulate regions for thermal processing.
• Hypothalamus functions appear to be associated with a secondary network distinct from the primary somatomotor-cingulate hub.
• These findings provide new insights into the central processing of thermal information and its affective components.