Learning in trance: functional brain imaging studies and neuropsychology

Area of Science:

• Neuroscience
• Cognitive Psychology

Background:

• Verbal memory encoding and retrieval involve complex neural systems.
• Hypnosis is a state of consciousness with altered perception and attention.
• The neural basis of memory processing during hypnosis remains incompletely understood.

Purpose of the Study:

• To investigate whether verbal memory processing in hypnosis and the waking state utilizes common or distinct neural systems.
• To explore the neural correlates of hypnotic susceptibility and its effect on memory.

Main Methods:

• Positron Emission Tomography (PET) scans using O-15 water to measure brain activity.
• Comparison of brain activation during encoding and retrieval of word associations in hypnosis versus the waking state.
• Assessment of memory recall for high-imagery and abstract words in highly hypnotizable individuals.

Main Results:

• Encoding under hypnosis showed increased bilateral activation in the occipital and prefrontal cortex compared to the waking state.
• Memory retrieval after hypnosis learning activated the occipital lobe and cerebellum.
• Consistent bilateral activation in the precuneus and prefrontal cortex was most pronounced during hypnosis-induced learning.
• Highly hypnotizable individuals demonstrated significantly better recall of high-imagery words under hypnosis.

Conclusions:

• Hypnosis modulates neural systems involved in verbal memory processing, particularly for imagery-based information.
• Distinct cortical areas are engaged during memory processing in hypnosis versus the waking state.
• Findings contribute to understanding the neuropsychological underpinnings of hypnosis and hypnotic susceptibility.