Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

High-speed magnetic resonance (MR) imaging was used to detect activation in the human prefrontal cortex induced by a spatial working memory task modeled on those used to elucidate neuronal circuits in nonhuman primates. Subjects were required to judge whether the location occupied by the current stimulus had been occupied previously over a sequence of 14 or 15 stimuli presented in various locations. Control tasks were similar in all essential respects, except that the subject's task was to detect when one of the stimuli presented was colored red (color detection) or when a dot briefly appeared within the stimulus (dot detection). In all tasks, two to three target events occurred randomly. The MR signal increased in an area of the middle frontal gyrus corresponding to Brodmann's area 46 in all eight subjects performing the spatial working memory task. Right hemisphere activation was greater and more consistent than left. The MR signal change occurred within 6-9 sec of task onset and declined within a similar period after task completion. An increase in MR signal was also noted in the control tasks, but the magnitude of change was less than that recorded in the working memory task. These differences were replicated when testing was repeated in five of the original subjects. The localization of spatial working memory function in humans to a circumscribed area of the middle frontal gyrus supports the compartmentalization of working memory functions in the human prefrontal cortex and the localization of spatial memory processes to comparable areas in humans and nonhuman primates.

Original publication

DOI

10.1073/pnas.91.18.8690

Type

Journal article

Journal

Proc Natl Acad Sci U S A

Publication Date

30/08/1994

Volume

91

Pages

8690 - 8694

Keywords

Color Perception, Female, Humans, Magnetic Resonance Imaging, Male, Memory, Prefrontal Cortex, Space Perception