Activity inhibition: a predictor of lateralized brain function during stress?

Area of Science:

• Cognitive Neuroscience
• Psycholinguistics
• Hemispheric Specialization

Background:

• Activity inhibition (AI) is a linguistic measure reflecting the use of negation, such as the word 'not'.
• Previous research suggests a link between AI and physiological stress responses, immune function, and behavior.
• The current study investigates AI's relationship with hemispheric engagement, particularly under stress.

Purpose of the Study:

• To test the hypothesis that high AI indicates a propensity to engage right hemisphere (RH) functions and disengage left hemisphere (LH) functions.
• To examine the influence of mood and affective stimuli on the AI-laterality effect.
• To explore the role of situational stress in modulating the AI-laterality effect.

Main Methods:

• Four studies were conducted, involving behavioral tasks measuring stimulus detection and attentional laterality.
• Participants' AI was assessed based on written material.
• Mood states and affective stimuli were manipulated to examine their interaction with AI and hemispheric processing.

Main Results:

• Higher AI predicted faster detection of stimuli presented to the RH compared to the LH.
• This AI-laterality effect was specific to perceptual tasks and modulated by mood, being stronger in low mood.
• Negative affective stimuli and situational frustration amplified the AI-laterality effect.

Conclusions:

• The findings support AI as a valid measure of hemispheric engagement patterns, particularly under stress.
• AI is linked to perceptual laterality, mood, and responses to negative affect.
• This research deepens the understanding of AI's connection to stress, physiology, and behavior.