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2 Potts units with dilute connectivity
S+1 Potts states Sparse Potts patterns Reduced to a Potts model (Kropff & Treves, 2005) Structured long-range connectivity “0” state included Sparse global patterns updated to remove the ‘memory glass’ problem (Fulvi Mari & Treves, 1998) Cortical modules Local attractor states Global activity patterns A simple semantic network (O’Kane & Treves, 1992) ..but all cortical modules share the same organization… pc  C S 2 !! pc  S ?!?!

3 Simulations which include a model of neuronal fatigue Simulations
show that the Potts semantic network can hop from global attractor to global attractor: Latching dynamics

4 Hauser, Chomsky & Fitch

5 if transition probabilities are structured,
Latching dynamics, if transition probabilities are structured, might be a neural model for infinite recursion

6 Monkey recordings by Moshe Abeles et al

7 How might have a capacity for indefinite latching evolved?
semantics  semantics  AM AM C S long-range conn  (local conn ) Storage capacity (max p to allow cued retrieval) pc  C S 2 Latching onset (min p to ensure recursive process) pl  S ? a spontaneous transition to infinite recursion?

8 G Elston et al

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10 Latching may be a neural basis for infinite recursion only if
transition probabilities are structured, so that dynamics are neither random not deterministic determ rand pl  S ? pc  C S 2 ? + we need to confirm the crucial quantitative relationships, e.g. that in a multi-factor coding model (with correlated patterns) Emilio Kropff has taken care of that (J Nat Comput, 2006)

11 Computer simulations of
Frontal Latching Networks with N = 300 Potts units a = 0.25 sparse coding S = 3,4,5,7, states C = 12,17,25,50,100 connections p = patterns generated by 20 relevant factors How to quantify retrieval ? and latching ?

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16 Retrieval and latching appear to coexist
only above critical values of both C and S Is that to FLNs a percolation phase transition?


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