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Stochastic and synchronous neural circuit dynamics underlying feature-similarity gain modulation. Xiao-Jing Wang With Salvador Ardid and Albert Compte. A recurrent network mechanism for working memory. Compte, Brunel, Goldman-Rakic and Wang 2000. A network model of PFC/PPC-MT loop.
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Stochastic and synchronous neural circuit dynamics underlying feature-similarity gain modulation Xiao-Jing Wang With Salvador Ardid and Albert Compte
A recurrent network mechanism for working memory Compte, Brunel, Goldman-Rakic and Wang 2000
A network model of PFC/PPC-MT loop Compte et al Cereb Cortex 2000 Ardid et al J Neurosci 2007
Calibrate MT network:normalization by strong recurrent inhibition Input coming from V1 MT model output Snowden, Treue, Erickson, Andersen 1991; Heeger 1992
no-attention + + + A Att S No-Att 2sec attention + t + + 55Hz Neural label PFC MT
Att no Att Network activity pattern shows selective enhancement Neural label
Multiplicative gain modulation of tuning curve MT model neuron response scaled responses Att: pref Att: nonpref Att: at 90
Network pattern in a single trial MT activity when A=S are covaried Att no Att Neural label Martinez-Trujillo and Treue, 2004 R(,S,A)=G(A-) R0(-S)
example MT cell Population data Martinez-Trujillo and Treue, 2004 Modulation ratio
Feature-similarity R(-S,-A)=G(A-) R0(-S) G(A-)= 1+g0 cos(A-) R(,S,A)=R(-S,-A,A-S) Multiplicative scaling of single cell’s tuning curve But selective enhancement of population activity profile in single trials
+ + + 2sec Transparent motion with attention Without attention + + + 55Hz PFC MT
Att no Att Neural label Network Activity pattern R(,S,A)=G(A-) R0(-S)
Att no Att prediction Neural label Feature-similarity gain principle holds for transparent motion R(-S,-A)=G(A-) R0(-S)
Biased competition 45Hz