Temporal dynamics of brain activation during a working memory task
Jonathan D. Cohen,Jonathan D. Cohen,William M. Perlstein,Todd S. Braver,Leigh E. Nystrom,Douglas C. Noll,John Jonides,Edward E. Smith +7 more
TLDR
Functional magnetic resonance imaging is used to examine brain activation in human subjects during performance of a working memory task and to show that prefrontal cortex along with parietal cortex appears to play a role in active maintenance.Abstract:
Working memory is responsible for the short-term storage and online manipulation of information necessary for higher cognitive functions, such as language, planning and problem-solving. Traditionally, working memory has been divided into two types of processes: executive control (governing the encoding manipulation and retrieval of information in working memory) and active maintenance (keeping information available 'online'). It has also been proposed that these two types of processes may be subserved by distinct cortical structures, with the prefrontal cortex housing the executive control processes, and more posterior regions housing the content-specific buffers (for example verbal versus visuospatial) responsible for active maintenance. However, studies in non-human primates suggest that dorsolateral regions of the prefrontal cortex may also be involved in active maintenance. We have used functional magnetic resonance imaging to examine brain activation in human subjects during performance of a working memory task. We used the temporal resolution of this technique to examine the dynamics of regional activation, and to show that prefrontal cortex along with parietal cortex appears to play a role in active maintenance.read more
Citations
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Journal ArticleDOI
An integrative theory of prefrontal cortex function
Earl K. Miller,Jonathan D. Cohen +1 more
TL;DR: It is proposed that cognitive control stems from the active maintenance of patterns of activity in the prefrontal cortex that represent goals and the means to achieve them, which provide bias signals to other brain structures whose net effect is to guide the flow of activity along neural pathways that establish the proper mappings between inputs, internal states, and outputs needed to perform a given task.
Book ChapterDOI
Chapter 11 Working memory
TL;DR: This chapter demonstrates the functional importance of dopamine to working memory function in several ways and demonstrates that a network of brain regions, including the prefrontal cortex, is critical for the active maintenance of internal representations.
Journal ArticleDOI
The magical number 4 in short-term memory: a reconsideration of mental storage capacity.
TL;DR: A wide variety of data on capacity limits suggesting that the smaller capacity limit in short-term memory tasks is real is brought together and a capacity limit for the focus of attention is proposed.
Journal ArticleDOI
Working memory: looking back and looking forward
TL;DR: The concept of working memory proposes that a dedicated system maintains and stores information in the short term, and that this system underlies human thought processes.
Journal ArticleDOI
An fMRI Investigation of Emotional Engagement in Moral Judgment
Joshua D. Greene,R. Brian Sommerville,Leigh E. Nystrom,John M. Darley,Jonathan D. Cohen,Jonathan D. Cohen +5 more
TL;DR: It is argued that moral dilemmas vary systematically in the extent to which they engage emotional processing and that these variations in emotional engagement influence moral judgment.
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Improved assessment of significant activation in functional magnetic resonance imaging (fMRI) : use of a cluster-size threshold
Steven D. Forman,Jonathan D. Cohen,Mark Fitzgerald,William F. Eddy,Mark A. Mintun,Douglas C. Noll +5 more
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