Working memory as an emergent property of the mind

Department of Psychology, University of Wisconsin-Madison, 1202 West Johnson Street, Madison, WI 53726, USA.
Neuroscience (Impact Factor: 3.36). 05/2006; 139(1):23-38. DOI: 10.1016/j.neuroscience.2005.06.005
Source: PubMed


Cognitive neuroscience research on working memory has been largely motivated by a standard model that arose from the melding of psychological theory with neuroscience data. Among the tenets of this standard model are that working memory functions arise from the operation of specialized systems that act as buffers for the storage and manipulation of information, and that frontal cortex (particularly prefrontal cortex) is a critical neural substrate for these specialized systems. However, the standard model has been a victim of its own success, and can no longer accommodate many of the empirical findings of studies that it has motivated. An alternative is proposed: Working memory functions arise through the coordinated recruitment, via attention, of brain systems that have evolved to accomplish sensory-, representation-, and action-related functions. Evidence from behavioral, neuropsychological, electrophysiological, and neuroimaging studies, from monkeys and humans, is considered, as is the question of how to interpret delay-period activity in the prefrontal cortex.

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    • "This is in contrast to the reductionist perspective that a complex system can be fully understood by gaining knowl - edge of its isolated parts ( Kitano , 2002 ) . Many types of sys - tems reveal that its patterns are greater than the sum of its parts , such as ant colonies ( Solé , Miramontes , & Goodwin , 1993 ) , traffic patterns ( Schreckenberg , Schadschneider , Nagel , & Ito , 1995 ) , and psychological constructs such as working memory ( Postle , 2006 ) . With regard to the effects of swishing glucose , a simplis - tic depletion model cannot account for these findings in exer - cise endurance or in self - regulatory persistence . "
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    • "Maintenance of a feature in VWM involves sustained activation of feature-specific neural populations in sensory cortex (Harrison & Tong, 2009; Postle, 2006; Serences et al., 2009), which is likely to interact with subsequent sensory processing, biasing competition for selection in favor of the remembered feature (Bundesen, 1990; Desimone & Duncan, 1995; Duncan & Humphreys, 1989; Wolfe, 1994). Thus, attention will be drawn to objects containing the to-be-avoided feature, a consequence of the demand to remember which feature to avoid. "
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    • "Present results are in line with findings regarding frontal–parietal coherence increase. Similar to Jonides et al. (2008), Postle (2006) describes STM as an emergent property of frontal– posterior interactions. Sarnthein et al. (1998) obtained an increase in frontal–posterior theta coherence. "
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