Spontaneous symmetry breaking and the onset of chaos in a muscle model.
The Hill length-tension curve of a muscle fibre is not linear. This had led us to investigate the behaviour of a model muscle sarcomere. The muscle is modelled as an oscillator of mass m subject to a nonlinear restoring force, a periodic external driving force and friction. We have found that this simple, idealized model exhibits spontaneous symmetry breaking and transition to chaos via a period doubling sequence. This result suggests that the nonlinearity in the length-tension curve of a muscle fibre could be responsible for irregular temporal behaviour and muscle tremor.
Barenghi
C F
CF
Department of Mathematics and Statistics, The University, Newcastle upon Tyne, UK.
Lakshminarayanan
V
V
D000818:Animals; D006801:Humans; D008433:Mathematics; D008954:Models, Biological; D009068:Movement; D009119:Muscle Contraction; D009132:Muscles / Q000294:innervation / Q000502:physiology*; D009991:Oscillometry; D012518:Sarcomeres / Q000502:physiology