A Modeling Approach on Why Simple Central Pattern Generators Are Built of Irregular Neurons

Autor(es)

Reyes, Marcelo Bussotti ^{[1, 2]} ; Carelli, Pedro Valadao ^{[1, 3]} ; Sartorelli, Jose Carlos ^[1] ; Pinto, Reynaldo Daniel ^{[1, 4]}

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Fis, BR-01498 Sao Paulo - Brazil

^[2] Univ Fed ABC, Ctr Matemat Comp & Cognicao, Santo Andre - Brazil

^[3] Univ Fed Pernambuco, Dept Fis, BR-50739 Recife, PE - Brazil

^[4] Univ Sao Paulo, Inst Fis Sao Carlos, Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PLoS One; v. 10, n. 3 MAR 23 2015.
• Citações Web of Science: 4

Resumo

The crustacean pyloric Central Pattern Generator (CPG) is a nervous circuit that endogenously provides periodic motor patterns. Even after about 40 years of intensive studies, the rhythm genesis is still not rigorously understood in this CPG, mainly because it is made of neurons with irregular intrinsic activity. Using mathematical models we addressed the question of using a network of irregularly behaving elements to generate periodic oscillations, and we show some advantages of using non-periodic neurons with intrinsic behavior in the transition from bursting to tonic spiking (as found in biological pyloric CPGs) as building components. We studied two-and three-neuron model CPGs built either with HindmarshRose or with conductance-based Hodgkin-Huxley-like model neurons. By changing a model's parameter we could span the neuron's intrinsic dynamical behavior from slow periodic bursting to fast tonic spiking, passing through a transition where irregular bursting was observed. Two-neuron CPG, half center oscillator (HCO), was obtained for each intrinsic behavior of the neurons by coupling them with mutual symmetric synaptic inhibition. Most of these HCOs presented regular antiphasic bursting activity and the changes of the bursting frequencies was studied as a function of the inhibitory synaptic strength. Among all HCOs, those made of intrinsic irregular neurons presented a wider burst frequency range while keeping a reliable regular oscillatory (bursting) behavior. HCOs of periodic neurons tended to be either hard to change their behavior with synaptic strength variations (slow periodic burster neurons) or unable to perform a physiologically meaningful rhythm (fast tonic spiking neurons). Moreover, 3-neuron CPGs with connectivity and output similar to those of the pyloric CPG presented the same results. (AU)

• Processo FAPESP: 98/15902-8 - Espaco de parametros na dinamica de formacao de gotas d'agua.
• Beneficiário: Marcelo Bussotti Reyes
• Linha de fomento: Bolsas no Brasil - Mestrado