A chronometric study of the posterior cerebellum's function in emotional processing.

Area of Science:

• Neuroscience
• Social Neuroscience
• Cognitive Neuroscience

Background:

• The posterior cerebellum is an emerging hub for social and affective brain functions.
• The precise timing of cerebellar involvement in social processing remains largely unknown.
• Studying cerebellar chronometry is challenging due to its anatomical location.

Purpose of the Study:

• To investigate the causal, time-sensitive role of the posterior cerebellum in social processing.
• To elucidate the functional connectivity between the cerebellum and key social brain regions.
• To determine the temporal dynamics of cerebellar engagement during emotional tasks.

Main Methods:

• Utilized chronometric transcranial magnetic stimulation (TMS) to probe cerebellar function.
• Employed a condition-and-perturb TMS approach to assess causal dependencies.
• Measured the timing of neural recruitment in the posterior cerebellum and pSTS.

Main Results:

• The posterior cerebellum is activated early in emotional processing, beginning around 100 ms post-stimulus onset.
• Cerebellar activation occurs concurrently with the posterior superior temporal sulcus (pSTS), a known social brain region.
• pSTS recruitment for emotional processing causally depends on posterior cerebellar activation.

Conclusions:

• This study provides the first chronometric insights into posterior cerebellar function in social cognition.
• Demonstrates a causal and time-dependent functional connection between the cerebellum and the pSTS.
• Highlights the cerebellum's critical early role in the social brain network.