Time and direction preparation of the long latency stretch reflex |
| |
| Affiliation: | 1. Balance and Neurodegeneration Laboratory, Bosch Institute, Discipline of Physiology, The University of Sydney, Sydney, NSW, Australia;2. Sainsbury Wellcome Centre for Neural Circuits and Behaviour, University College London, London, United Kingdom;3. Department of Clinical and Experimental Medicine; Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden;1. Department of Neurological Science, Nippon Medical School Hospital, Tokyo, Japan;2. Department of Neurological Science, Nippon Medical School Tama Nagayama Hospital, Tokyo, Japan;1. Department of Physical Therapy, Faculty of Physical Therapy, University of Valencia, Gascó Oliag street, 5, 46010, Valencia, Spain;2. Biomechanics Institute of Valencia, Universitat Politécnica de Valéncia, Camí de Vera s/n, edificio 9C, 46022, Valencia, Spain;3. Hospital Universitari i Politècnic La Fe, Avinguda de Fernando Abril Martorell, 106, 46026, Valencia, Spain |
| |
| Abstract: | This study investigated time and direction preparation of motor response to force load while intending to maintain the finger at the initial neutral position. Force load extending or flexing the index finger was given while healthy humans intended to maintain the index finger at the initial neutral position. Electromyographic activity was recorded from the first dorsal interosseous muscle. A precue with or without advanced information regarding the direction of the forthcoming force load was given 1000 ms before force load. Trials without the precue were inserted between the precued trials. A long latency stretch reflex was elicited by force load regardless of its direction, indicating that the long latency stretch reflex is elicited not only by muscle stretch afferents, but also by direction-insensitive sensations. Time preparation of motor response to either direction of force load enhanced the long latency stretch reflex, indicating that time preparation is not mediated by afferent discharge of muscle stretch. Direction preparation enhanced the long latency stretch reflex and increased corticospinal excitability 0–20 ms after force load when force load was given in the direction stretching the muscle. These enhancements must be induced by preset of the afferent pathway mediating segmental stretch reflex. |
| |
| Keywords: | Perturbation Force load Long latency stretch reflex First dorsal interosseous muscle Prediction |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
