Stochastic and synchronous neural circuit dynamics

1
Stochastic and synchronous neural circuit
dynamics underlying feature-similarity gain
modulation
Xiao-Jing Wang With Salvador Ardid and Albert
Compte
2
A recurrent network mechanism for working memory
Compte, Brunel, Goldman-Rakic and Wang 2000
3
A network model of PFC/PPC-MT loop
Compte et al Cereb Cortex 2000
Ardid et al J Neurosci 2007
4
Calibrate MT networknormalization by strong
recurrent inhibition
Input coming from V1
MT model output
Snowden, Treue, Erickson, Andersen 1991 Heeger
1992
5
attention

t


55Hz
Neural label ?
PFC
MT
6
Network activity pattern shows selective
enhancement
Neural label ?
7
Multiplicative gain modulation of tuning curve
scaled responses
MT model neuron response
Att pref
Att nonpref
Att at 90
8
Martinez-Trujillo and Treue (Current Biol 2004)
9
R(?,?S,?A)G(?A-?) R0(?-?S)
10
Modulation ratio
11
R(?,?S,?A)R(?-?S,?-?A,?A-?S)
Multiplicative scaling of single cells tuning
curve But selective enhancement of population
activity profile in single trials
12
Transparent motion with attention
Without attention



55Hz
PFC
MT
13
Network Activity pattern
R(?,?S,?A)G(?A-?) R0(?-?S)
14
Feature-similarity gain principle holds for
transparent motion
R(?-?S,?-?A)G(?A-?) R0(?-?S)
15
Biased competition
45Hz