Heterogeneous attractor cell assemblies for motor planning in premotor cortex.
J Neurosci
; 33(27): 11155-68, 2013 Jul 03.
Article
em En
| MEDLINE
| ID: mdl-23825419
ABSTRACT
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.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Desempenho Psicomotor
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Intenção
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Córtex Motor
/
Movimento
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
J Neurosci
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Itália