An evolving view of duplex vision: Separate but interacting cortical pathways for perception and action

Current Opinion in Neurobiology

Volumn 14, Issue 2, 2004, Pages 203-211

  Goodale, Melvyn A ^a   Westwood, David A ^b  

^a UNIVERSITY OF WESTERN ONTARIO   (Canada)

^b DALHOUSIE UNIVERSITY   (Canada)

Author keywords

AIP; Anterior intraparietal sulcus; Area LO; fMRI; Functional magnetic resonance imaging; Lateral occipital area; Lateral occipital complex; LOC; Magnetic resonance imaging; MRI; RF; Rod and frame; Simultaneous tilt; ST; TMS; Transcranial magnetic stimulation

Indexed keywords

ANTICIPATION; ARM MOVEMENT; ATAXIA; BEHAVIOR; BRAIN CORTEX; BRAIN INJURY; BRAIN REGION; DECISION MAKING; HAND GRIP; HAND MOVEMENT; HUMAN; HYPOTHESIS; MONKEY; NERVE CELL NETWORK; NEUROIMAGING; NEUROPSYCHOLOGY; NONHUMAN; NUCLEAR MAGNETIC RESONANCE IMAGING; OCCIPITAL CORTEX; PERCEPTION; PRIORITY JOURNAL; RECOGNITION; REVIEW; SACCADIC EYE MOVEMENT; SPATIAL ORIENTATION; TEMPORAL CORTEX; VISUAL ILLUSION; VISUAL STIMULATION; VISUOMOTOR COORDINATION;

ANIMALS; HUMANS; ILLUSIONS; MODELS, NEUROLOGICAL; PARIETAL LOBE; PSYCHOMOTOR PERFORMANCE; TEMPORAL LOBE; VISUAL CORTEX; VISUAL PATHWAYS; VISUAL PERCEPTION;

EID: 1842684456     PISSN: 09594388     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.conb.2004.03.002     Document Type: Review

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80. ••] cited in this review, and add to a growing body of evidence suggesting that the segregation between vision-for-action and vision-for-perception occurs downstream of motion processing regions.
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82. Schwartz A.B., Moran D.W., Reina G.A. Differential representation of perception and action in the frontal cortex. Science. 303:2004;380-383 Using a virtual manual-tracking task in which the mapping between actual and displayed hand position was gradually altered, the authors created a dissociation between the perceived (elliptical) and the actual (circular) trajectory of the limb in both humans and monkeys. Humans reported no awareness of the illusion, suggesting that the visual feedback of their virtual limb dominated conscious perception of action. Using the same task, single-unit recordings in monkey ventral premotor cortex (PMv) and primary motor cortex (M1) were used to explore neural representations of the hand's trajectory. Activity in M1 reflected more closely the actual trajectory, whereas activity in PMv was more closely linked to the perceived trajectory. The authors suggested that a sub-population of neurons in PMv play a leading role in 'vision-for-perception', at least in the context of perceiving and monitoring one's own actions. Although it is not yet clear how these findings relate to the perception-action model (which focuses on the visual processing of objects rather than actions), this study is noteworthy for attempting to identify the neurobiological basis for differences between conscious perception and control of action.