When the brain loses its self: prefrontal inactivation during sensorimotor processing.

Ilan I Goldberg; Michal Harel; Rafael Malach

doi:10.1016/j.neuron.2006.03.015

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When the brain loses its self: prefrontal inactivation during sensorimotor processing.

Ilan I Goldberg·Michal Harel·Rafael Malach

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Abstract

A common theme in theories of subjective awareness poses a self-related "observer" function, or a homunculus, as a critical element without which awareness can not emerge. Here, we examined this question using fMRI. In our study, we compared brain activity patterns produced by a demanding sensory categorization paradigm to those engaged during self-reflective introspection, using similar sensory stimuli. Our results show a complete segregation between the two patterns of activity. Furthermore, regions that showed enhanced activity during introspection underwent a robust inhibition during the demanding perceptual task. The results support the notion that self-related processes are not necessarily engaged during sensory perception and can be actually suppressed.

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Acoustic Stimulation Adult Brain Mapping Female Humans Magnetic Resonance Imaging Male Photic Stimulation Prefrontal Cortex Self Concept Comparative Study Journal Article Research Support, Non-U.S. Gov't

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Ilan I Goldberg, Michal Harel, Rafael Malach. 2006-04-20. When the brain loses its self: prefrontal inactivation during sensorimotor processing.. https://doi.org/10.1016/j.neuron.2006.03.015

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