Figure 1.
Persistent activity during working memory may be generated through a balanced
increase in recurrent excitation and inhibition within a subgroup of cortical
neurons. A. In one classical paradigm of working memory, the animal
is required to fixate a center point and to remember for a few seconds the
location of a target that is briefly flashed on screen. After the delay
(memory) period, the animal performs a saccade to the target. Neurons
in the prefrontal cortex maintain activity at 5-40 Hz during the delay period
and this activity is specific for the location of the target to be remembered.
B. Models of persistent activity in networks of cortical cells
depend on recurrent excitation that is balanced by local inhibition. The
cessation of the activity is hypothesized to occur through a strong activition
of inhibitory neurons.
For more information see:
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