Pleasant Deep Pressure: Expanding the Social Touch Hypothesis

Area of Science:

• Neuroscience
• Somatosensation
• Social Psychology

Background:

• Research on pleasant touch primarily focused on the C-tactile pathway for gentle stroking.
• The C-tactile hypothesis suggests a privileged neural pathway for social/affective touch.
• Deep pressure touch, common in comforting interactions, has been less studied.

Purpose of the Study:

• To introduce a paradigm for studying pleasant deep pressure touch.
• To propose deep pressure as another significant form of social touch.
• To investigate the neural correlates of pleasant deep pressure.

Main Methods:

• Development of the oscillating compression sleeve (OCS) for administering controlled deep pressure.
• Functional magnetic resonance imaging (fMRI) to observe brain activity during deep pressure application.
• Comparison of brain activation patterns between deep pressure and C-tactile stroking.

Main Results:

• Deep pressure touch, delivered via OCS, was perceived as pleasant and calming.
• fMRI imaging demonstrated that deep pressure activates brain regions similar to those activated by C-tactile stroking.
• Deep pressure also activated distinct brain regions not engaged by gentle stroking.

Conclusions:

• Deep pressure represents a distinct and evolutionarily important social touch pathway.
• This pathway signals the close proximity of conspecifics, contributing to social bonding and regulation.
• Further research into deep pressure's neural basis is warranted.