Relaxation as a cognitive task.

Area of Science:

• Neuroscience
• Psychophysiology
• Cognitive Science

Background:

• Hypnotizability is a trait influencing cognitive and physiological responses.
• Understanding distinct brain activity patterns in relation to hypnotizability is crucial for cognitive neuroscience.

Purpose of the Study:

• To investigate the psychophysiological and electroencephalogram (EEG) differences between highly hypnotizable (Highs) and non-hypnotizable (Lows) subjects during a relaxation task.
• To explore the cognitive strategies employed by different hypnotizability groups.

Main Methods:

• Simultaneous recording of electroencephalogram (EEG), electrooculogram (EOG), corrugator electromyogram (EMG), heart rate (HR), respiratory frequency (RF), and skin resistance.
• Subjects included awake highly hypnotizable (Highs) and non-hypnotizable (Lows) individuals.
• Analysis of EEG power spectra (alpha, theta1, theta2, beta2, gamma) and heart rate variability (HRV) components.

Main Results:

• Initially, Highs showed higher EEG alpha and theta1 power than Lows, with no significant HR, RF, or HRV differences.
• During relaxation, both groups decreased HR, but significantly only in Lows, who also increased high frequency (HF) HRV.
• EEG changes included alpha, beta2, and theta2 power decrements in both groups; theta1 decreased only in Lows, while gamma power increased in Highs and decreased in Lows.

Conclusions:

• Highly hypnotizable and non-hypnotizable individuals employ different cognitive strategies when responding to relaxation instructions.
• High hypnotizability is associated with greater integrative brain activity during relaxation tasks.
• Distinct patterns of psychophysiological and neural responses differentiate individuals based on hypnotizability.