Signals in tactile afferents from the fingers eliciting adaptive motor responses during precision grip

@article{Johansson2004SignalsIT,
  title={Signals in tactile afferents from the fingers eliciting adaptive motor responses during precision grip},
  author={Roland S. Johansson and G{\"o}ran Westling},
  journal={Experimental Brain Research},
  year={2004},
  volume={66},
  pages={141-154}
}
SummaryWhile human subjects lift small objects using the precision grip between the tips of the fingers and thumb the ratio between the grip force and the load force (i.e. the vertical lifting force) is adapted to the friction between the object and the skin. The present report provides direct evidence that signals in tactile afferent units are utilized in this adaptation. Tactile afferent units were readily excited by small but distinct slips between the object and the skin revealed as… Expand
Control of grip force during restraint of an object held between finger and thumb: responses of cutaneous afferents from the digits
TLDR
The high density of FA I receptors in the digits might place the FA I afferents in a unique position to convey the information required to initiate and scale the reactive gripforce responses to the imposed load forces. Expand
Tactile afferents encode grip safety before slip for different frictions
TLDR
This work was to investigate whether a population of human tactile afferents can provide information about the current tangential/normal force ratio expressed as the percentage of the critical load capacity - the tangential / normal force ratio at which the object would slip. Expand
Nondigital afferent input in reactive control of fingertip forces during precision grip
TLDR
Sensory inputs from the digits are dominant in reactive grip control, however, nondigital sensory input may be used for some grip control during impaired digital sensibility, which depends on the extent of movements evoked by the load in the distal, unanesthetized parts of the arm. Expand
Contribution of tactile afferent information to the control of isometric finger forces
TLDR
Findings suggest tactile afferent information at the fingertip is important for determining the voluntary force exerted by the finger and must be properly integrated with other peripheral information as well as with the central motor command, otherwise the perception of force is distorted. Expand
Contribution of tactile feedback from the hand to the perception of force
TLDR
The results suggest that the perception of force is influenced by tactile cues that convey information about the contact surface and that distributed spatial force cues are normally used in the Perception of forces generated by the hand. Expand
Role of Tactile Noise in the Control of Digit Normal Force
TLDR
The results suggest that, in each finger opposing thumb, digit normal force is controlled locally in response to the applied tactile perturbation. Expand
Influence of tactile afferents on the coordination of muscles during a simulated precision grip
TLDR
It is suggested that tactile input is not required to activate the divergent last-order inputs that couple together the activities of the index finger and thumb flexor muscles during the precision grip. Expand
Control of grip force during restraint of an object held between finger and thumb: responses of muscle and joint afferents from the digits
TLDR
Mechanoreceptors in the flexors of the digits and in the interphalangeal joints cannot be awarded a significant role in triggering the automatic changes in grip force, and it appears that tactile afferents of the skin in contact with the object are the only species of receptor in the hand capable of triggering and initially scaling an appropriate change in gripForce. Expand
Development of human precision grip
TLDR
The present finding suggests that young children use excessive grip force, a strategy to avoid frictional slips, to compensate for an immature tactile control of the precision grip. Expand
Somatosensory control of precision grip during unpredictable pulling loads
TLDR
The grip forceregulation was impaired under any condition of digital anesthesia, i.e., afferent input from both index finger and thumb was required for the adequate operation of the grip force regulation. Expand
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