Exposure shapes the perception of affective touch

Area of Science:

• Psychology
• Neuroscience
• Somatosensation

Background:

• Interpersonal touch is crucial for well-being, influencing affective and social aspects.
• Tactile perception encompasses both discriminative (intensity, texture) and hedonic (pleasantness) qualities.
• Individual differences in touch exposure may modulate these perceptual qualities.

Purpose of the Study:

• To investigate the impact of touch exposure frequency on hedonic and discriminative tactile perception.
• To compare tactile pleasantness and intensity judgments between individuals with low and high interpersonal touch exposure.
• To explore the relationship between touch appreciation and perceived pleasantness of touch.

Main Methods:

• Assessed perceived pleasantness and intensity of gentle forearm stroking at various velocities.
• Recruited participants reporting infrequent interpersonal touch (low exposure) and frequent touch (controls).
• Utilized physiological and questionnaire measures alongside tactile assessments.

Main Results:

• No significant differences were found in tactile intensity judgments or discrimination sensitivity between groups.
• Individuals with low touch exposure exhibited altered pleasantness ratings for gentle stroking.
• The low touch exposure group showed a flatter pleasantness curve and rated 3cm/s stroking as less pleasant compared to controls.

Conclusions:

• Reduced interpersonal touch exposure significantly affects the hedonic evaluation of tactile stimuli.
• The association between familiar touch and perceived pleasantness may be dependent on the frequency of touch exposure.
• Findings highlight the role of experience in shaping the affective dimension of tactile perception.