Simon C. Gandevia

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Muscle fatigue is an exercise-induced reduction in maximal voluntary muscle force. It may arise not only because of peripheral changes at the level of the muscle, but also because the central nervous system fails to drive the motoneurons adequately. Evidence for "central" fatigue and the neural mechanisms underlying it are reviewed, together with its(More)
Recently, transcranial magnetic stimulation of the motor cortex (TMS) revealed impaired voluntary activation of muscles during maximal efforts. Hence, we evaluated its use as a measure of voluntary activation over a range of contraction strengths in both fresh and fatigued muscles, and compared it with standard twitch interpolation using nerve stimulation.(More)
1. To identify the vestibular contribution to human standing, responses in leg muscles evoked by galvanic vestibular stimulation were studied. Step impulses of current were applied between the mastoid processes of normal subjects and the effects on the soleus and tibialis anterior electromyograms (EMGs), ankle torque, and body sway were identified by(More)
1. Voluntary activation of elbow flexor muscles can be optimal during brief maximal voluntary contractions (MVCs), although central fatigue, a progressive decline in the ability to drive the muscle maximally, develops during sustained or repeated efforts. We stimulated the motor cortex and motor point in human subjects to investigate motor output during(More)
If exercises are performed to increase muscle strength on one side of the body, voluntary strength can increase on the contralateral side. This effect, termed the contralateral strength training effect, is usually measured in homologous muscles. Although known for over a century, most studies have not been designed well enough to show a definitive transfer(More)
The most obvious impairments associated with spinal cord injury (SCI) are loss of sensation and motor control. However, many subjects with SCI also develop persistent neuropathic pain below the injury which is often severe, debilitating and refractory to treatment. The underlying mechanisms of persistent neuropathic SCI pain remain poorly understood.(More)
1. In this study we measured the loop gain of postural reflexes in standing human subjects. Reflex activity is conventionally described in terms of the muscle activation arising from a perturbation, but in this study the ability of the evoked muscle activity to correct the perturbation was also measured, and the behavior of the entire feedback loop is(More)
1. Knowledge of the size and orientation of the hand is essential if it is to be moved accurately in space. We used two psychophysical methods to determine whether the perceived size of a body part changes when its sensory input is changed: first, the selection of scaled drawings which matched the apparent size of a body part, and second, a motor task in(More)
This is a review of the proprioceptive senses generated as a result of our own actions. They include the senses of position and movement of our limbs and trunk, the sense of effort, the sense of force, and the sense of heaviness. Receptors involved in proprioception are located in skin, muscles, and joints. Information about limb position and movement is(More)
Many studies have identified changes in trunk muscle recruitment in clinical low back pain (LBP). However, due to the heterogeneity of the LBP population these changes have been variable and it has been impossible to identify a cause-effect relationship. Several studies have identified a consistent change in the feedforward postural response of transversus(More)