PT  - JOURNAL ARTICLE
AU  - Maurizio Mattia
AU  - Pierpaolo Pani
AU  - Giovanni Mirabella
AU  - Stefania Costa
AU  - Paolo Del Giudice
AU  - Stefano Ferraina
TI  - Heterogeneous Attractor Cell Assemblies for Motor Planning in Premotor Cortex
AID  - 10.1523/JNEUROSCI.4664-12.2013
DP  - 2013 Jul 03
TA  - The Journal of Neuroscience
PG  - 11155--11168
VI  - 33
IP  - 27
4099  - http://www.jneurosci.org/content/33/27/11155.short
4100  - http://www.jneurosci.org/content/33/27/11155.full
SO  - J. Neurosci.2013 Jul 03; 33
AB  - Cognitive functions like motor planning rely on the concerted activity of multiple neuronal assemblies underlying still elusive computational strategies. During reaching tasks, we observed stereotyped sudden transitions (STs) between low and high multiunit activity of monkey dorsal premotor cortex (PMd) predicting forthcoming actions on a single-trial basis. Occurrence of STs was observed even when movement was delayed or successfully canceled after a stop signal, excluding a mere substrate of the motor execution. An attractor model accounts for upward STs and high-frequency modulations of field potentials, indicative of local synaptic reverberation. We found in vivo compelling evidence that motor plans in PMd emerge from the coactivation of such attractor modules, heterogeneous in the strength of local synaptic self-excitation. Modules with strong coupling early reacted with variable times to weak inputs, priming a chain reaction of both upward and downward STs in other modules. Such web of “flip-flops” rapidly converged to a stereotyped distributed representation of the motor program, as prescribed by the long-standing theory of associative networks.