Transcript Document

Reverberating activity in the brain
Single neuron stimulus selective sustained activity
Delayed matching to
sample task:
1s
Delay
Sample
stimulus
Test
stimulus
Yakovlev, Fusi, Berman, Zohary,
Nature Neuroscience 1998
Sustained reverberations as an expression
of the collective attractor’s dynamics
The landscape
metaphor:
•Each point
corresponds to a
collective state of
a population of
neurons
•The dynamical
process goes
downhill
Energy
30Hz
20Hz
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STIMULUS ‘A’
PRESENTATION
(before learning)
fa
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STIMULUS ‘B’
PRESENTATION
(before learning)
fa
Shaping landscapes: synaptic plasticity
Neurons activated by A
Neurons activated by B
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STIMULUS ‘A’
PRESENTATION
(after learning)
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STIMULUS
CLASSIFICATION
Presentation of
a degraded version of A
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Stimulus rate (Hz)
Amit, Fusi, Yakovlev, 1997