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下次必胜！ 找到working memory的参考文章 Working memory is the process of maintaining a limited
amount of information in an active representation for a
brief period of time so that it is available for use. There-
fore, by definition, working memory includes those
processes that enable us to hold in our `mind's eye' the
contents of our conscious awareness, even in the absence
of sensory input. Thus, the study of working memory
provides a framework for investigating the neural system
underlying our awareness of stimuli, memories and
knowledge that are no longer tied to perceptual events.
Although the neural system responsible for working
memory is known to include a large number of brain
regions, there is abundant evidence from neurophysio-
logical and lesion studies in monkeys that prefrontal
cortex is a critical component (Fuster 1990; Goldman-
Rakic 1990). Recent brain-imaging studies, using
positron emission tomography (PET) and functional
magnetic resonance imaging (fMRI), have also impli-
cated the human prefrontal cortex in working memory
. However, there remain questions and some
dispute about the functional organization of the human
prefrontal cortex and its exact role in working memory.
Here we summarize the evidence for working memory-
related activity within human prefrontal cortex.We then
present evidence for domain speci¢city within frontal
cortex for object working memory as opposed to spatial
visual working memory. We also review evidence
suggesting an additional dimension of domain speci¢city
for object working memory based on whether the type of
representation is analytic or image-like. In addition, we
discuss evidence suggesting a third dimension for the
specialization of working memory function in prefrontal
cortex that distinguishes regions important for the main-
tenance of the contents held in working memory from
regions important for the manipulation of those contents.
Finally, we consider the relationship of prefrontal areas
important for working memory, both to posterior visual
processing areas and to prefrontal areas associated with
long-term memory.
Working memory is the process of maintaining a limited
amount of information in an active representation for a
brief period of time so that it is available for use. There-
fore, by definition, working memory includes those
processes that enable us to hold in our `mind's eye' the
contents of our conscious awareness, even in the absence
of sensory input. Thus, the study of working memory
provides a framework for investigating the neural system
underlying our awareness of stimuli, memories and
knowledge that are no longer tied to perceptual events.
Although the neural system responsible for working
memory is known to include a large number of brain
regions, there is abundant evidence from neurophysio-
logical and lesion studies in monkeys that prefrontal
cortex is a critical component (Fuster 1990; Goldman-
Rakic 1990). Recent brain-imaging studies, using
positron emission tomography (PET) and functional
magnetic resonance imaging (fMRI), have also impli-
cated the human prefrontal cortex in working memory
. However, there remain questions and some
dispute about the functional organization of the human
prefrontal cortex and its exact role in working memory.
Here we summarize the evidence for working memory-
related activity within human prefrontal cortex.We then
present evidence for domain speci¢city within frontal
cortex for object working memory as opposed to spatial
visual working memory. We also review evidence
suggesting an additional dimension of domain speci¢city
for object working memory based on whether the type of
representation is analytic or image-like. In addition, we
discuss evidence suggesting a third dimension for the
specialization of working memory function in prefrontal
cortex that distinguishes regions important for the main-
tenance of the contents held in working memory from
regions important for the manipulation of those contents.
Finally, we consider the relationship of prefrontal areas
important for working memory, both to posterior visual
processing areas and to prefrontal areas associated with
long-term memory.
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发表于 2008-1-10 16:54:00
