Wang TINS 2001 Wang et al PNAS 2004
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Transcript of Wang TINS 2001 Wang et al PNAS 2004
Wang TINS 2001Wang et al PNAS 2004 Wang Neuron 2002
400ms
Lorente de Nó’s reverberatory circuit
Levitt et al 1993Kritzer and Goldman-Rakic 1995Pucak et al 1996
Summary
• Working memory storage and decision-making computations: shared microcircuit mechanisms in a local cortical (e.g. prefrontal, parietal, premotor) area. Coherent fast oscillation may be a common signature of the engagement of strongly recurrent network dynamics.
• Detection of threshold-crossing: a mode of communication between brain areas, for gating information flow or selecting a motor action.
• Reward-gated Hebbian plasticity in a decision network: a cellular basis of flexible sensori-motor mapping.
Probabilistic decision-making in a visual motion two-alternative forced choice task
W Newsome
Roitman and Shadlen 2002
• 2-population excitatory and inhibitory neurons (integrate-and-fire or conductance-based Hodgkin-Huxley neurons)
• Biologically realistic synaptic kinetics (AMPA, NMDA and GABA
A)
• Structured network connectivity
Brunel & Wang JCNS2001
Wang Neuron 2002
Dynamical stability and NMDA/AMPA
ratio at the recurrent synapses
C D RWang J Neurosci 1999
Compte, Brunel, Goldman-Rakic,Wang Cereb Cortex 2000
Brunel and Wang J Neurophysiol 2003
• 2-population excitatory and inhibitory neurons (integrate-and-fire or conductance-based neurons)
• Biologically realistic synaptic kinetics (AMPA, NMDA and GABA
A)
• Structured network connectivity
Brunel & Wang JCNS2001
Wang Neuron 2002
MT output
Reaction Time Simulations
Model
Data
Data by J Roitman, J Ditterich and M Shadlen
Reaction time decreases with increasing coherence Weber's Law
Scale-invariance of the reaction time distributions
c’=51.2%c’=0%
Integrate-and-Decide (diffusion) Model
J Schall (Nature Rev Neurosci 2001)
But how is threshold-crossing readout by downstream neurons?
Flexible sensori-motor association
(with Stefano Fusi)
Flexible Sensori-motor Association
(Asaad, Rainer and Miller Neuron 1998, Wise and Murray TINS 2000)
Locus and biophysical basis of reward-gated synaptic plasticity?
Summary
• Working memory storage and decision-making computations: shared microcircuit mechanisms in a local cortical (e.g. prefrontal, parietal, premotor) area. Coherent fast oscillation may be a common signature of the engagement of strongly recurrent network dynamics.
• Detection of threshold-crossing: a mode of communication between brain areas, for gating information flow or selecting a motor action.
• Reward-gated Hebbian plasticity in a decision network: a cellular basis of flexible sensori-motor mapping.