Visual Mental Imagery Activates Topographically Organized Visual Cortex: PET Investigations

DSpace/Manakin Repository

Visual Mental Imagery Activates Topographically Organized Visual Cortex: PET Investigations

Citable link to this page

. . . . . .

Title: Visual Mental Imagery Activates Topographically Organized Visual Cortex: PET Investigations
Author: Kosslyn, Stephen Michael; Alpert, Nathaniel Moritz; Thompson, William L.; Maljkovic, Vera; Weise, Steven B.; Chabris, Christopher F; Hamilton, Sania E.; Rauch, Scott Laurence; Buonanno, Ferdinando Stelio

Note: Order does not necessarily reflect citation order of authors.

Citation: Kosslyn, Stephen Michael, Nathaniel M. Alpert, William L. Thompson, Vera Maljkovic, Steven B. Weise, Christopher F. Chabris, Sania E. Hamilton, Scott L. Rauch, and Ferdinando S. Buonanno. 1993. Visual mental imagery activates topographically organized visual cortex: PET investigations. Journal of Cognitive Neuroscience 5(3): 263-287.
Full Text & Related Files:
Abstract: Cerebral blood flow was measured using positron emission tomography (PET) in three experiments while subjects performed mental imagery or analogous perceptual tasks. In Experiment 1, the subjects either visualized letters in grids and decided whether an X mark would have fallen on each letter if it were actually in the grid, or they saw letters in grids and decided whether an X mark fell on each letter. A region identified as part of area 17 by the Talairach and Tournoux (1988) atlas, in addition to other areas involved in vision, was activated more in the mental imagery task than in the perception task. In Experiment 2, the identical stimuli were presented in imagery and baseline conditions, but subjects were asked to form images only in the imagery condition; the portion of area 17 that was more active in the imagery condition of Experiment 1 was also more activated in imagery than in the baseline condition, as was part of area 18. Subjects also were tested with degraded perceptual stimuli, which caused visual cortex to be activated to the same degree in imagery and perception. In both Experiments 1 and 2, however, imagery selectively activated the extreme anterior part of what was identified as area 17, which is inconsistent with the relatively small size of the imaged stimuli. These results, then, suggest that imagery may have activated another region just anterior to area 17. In Experiment 3, subjects were instructed to close their eyes and evaluate visual mental images of upper case letters that were formed at a small size or large size. The small mental images engendered more activation in the posterior portion of visual cortex, and the large mental images engendered more activation in anterior portions of visual cortex. This finding is strong evidence that imagery activates topographically mapped cortex. The activated regions were also consistent with their being localized in area 17. Finally, additional results were consistent with the existence of two types of imagery, one that rests on allocating attention to form a pattern and one that rests on activating stored visual memories.
Published Version: doi:10.1162/jocn.1993.5.3.263
Terms of Use: This article is made available under the terms and conditions applicable to Other Posted Material, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#LAA
Citable link to this page: http://nrs.harvard.edu/urn-3:HUL.InstRepos:3626276

Show full Dublin Core record

This item appears in the following Collection(s)

  • FAS Scholarly Articles [7219]
    Peer reviewed scholarly articles from the Faculty of Arts and Sciences of Harvard University
 
 

Search DASH


Advanced Search
 
 

Submitters