Brain mechanisms for loss of awareness of thought and movement.
Loss or reduction of awareness is common in neuropsychiatric disorders and culturally influenced dissociative phenomena but the underlying brain mechanisms are poorly understood. fMRI was combined with suggestions for automatic writing in 18 healthy highly hypnotically suggestible individuals in a within-subjects design to determine whether clinical alterations in awareness of thought and movement can be experimentally modelled and studied independently of illness. Subjective ratings of control, ownership, and awareness of thought and movement, and fMRI data were collected following suggestions for thought insertion and alien control of writing movement, with and without loss of awareness. Subjective ratings confirmed that suggestions were effective. At the neural level, our main findings indicated that loss of awareness for both thought and movement during automatic writing was associated with reduced activation in a predominantly left-sided posterior cortical network including BA 7 (superior parietal lobule and precuneus), and posterior cingulate cortex, involved in self-related processing and awareness of the body in space. Reduced activity in posterior parietal cortices may underlie specific clinical and cultural alterations in awareness of thought and movement. Clinically, these findings may assist development of imaging assessments for loss of awareness of psychological origin, and interventions such as neurofeedback.
Cultural and Social Neuroscience Group, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, UK.|Department of Psychological Sciences, Birkbeck, University of London, UK.
Eamonn
E
Walsh
Division of Psychology and Language Sciences, University College London, UK.
David A
DA
Oakley
School of Psychology, Cardiff University, UK.
Peter W
PW
Halligan
Cultural and Social Neuroscience Group, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, UK.|Centre for Neuroimaging Sciences, King's College London, UK.
Mitul A
MA
Mehta
Cultural and Social Neuroscience Group, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, UK.
Quinton
Q
Deeley
D000328:Adult; D001364:Awareness / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D004213:Dissociative Disorders / Q000523:psychology; D007839:Functional Laterality / Q000502:physiology; D064368:Healthy Volunteers; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009068:Movement / Q000502:physiology*; D010296:Parietal Lobe / Q000502:physiology; D013404:Suggestion; D013850:Thinking / Q000502:physiology*; D055815:Young Adult
automatic writing; cultural neuroscience; dissociation; fMRI; hypnosis; non-epileptic seizures