Functional brain networks associated with the urge for action: Implications for pathological urge

Area of Science:

• Neuroscience
• Psychiatry
• Human Physiology

Background:

• Tourette syndrome (TS) is characterized by tics often preceded by sensory urges.
• Understanding the neural basis of these urges is crucial for TS research.
• Physiological urges offer a model to study the urge-to-act pathway.

Purpose of the Study:

• Identify a shared brain network underlying distinct physiological urges in healthy individuals.
• Compare this 'urge network' with a previously identified network in TS.
• Investigate the role of specific brain regions in the urge to tic.

Main Methods:

• Systematic literature search for functional neuroimaging studies on urges (micturition, swallowing, blinking, coughing).
• Activation Likelihood Estimation (ALE) meta-analysis to identify common brain networks.
• Coordinate network mapping to compare urge and TS networks.

Main Results:

• An 'urge network' was identified, involving bilateral insula/claustrum/inferior frontal gyrus/supplementary motor area, mid-/anterior- cingulate cortex (ACC), right postcentral gyrus, and left thalamus/precentral gyrus.
• Significant overlap was found between the general urge network and the TS network in the bilateral insula, ACC, and left thalamus/claustrum.
• These overlapping regions are implicated in processing bodily sensations and urges.

Conclusions:

• A common neural network underlies various physiological urges.
• The insula and ACC are potential key nodes in the neural circuitry of the urge to tic in TS.
• Further research into these brain regions may reveal therapeutic targets for tic reduction.