Loss of haptic feedback impairs control of hand posture: a study in chronically deafferented individuals when grasping and lifting objects
Research output: Contribution to journal › Article
Colleges, School and Institutes
- School of Psychology, University of Birmingham, Birmingham, B15 2TT, UK. firstname.lastname@example.org.
- School of Psychology, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; Department of Psychology, Lancaster University, Lancaster LA1 4YF, UK.
- Department of Neurology, Oslo University Hospital, Oslo, Norway.
- Clinical Neurophysiology, Poole Hospital, and Centre of Postgraduate Research and Education, University of Bournemouth, Poole, United Kingdom.
- Aix Marseille University, CNRS, ISM, Marseille, France.
Previous work has highlighted the role of haptic feedback for manual dexterity, in particular for the control of precision grip forces between the index finger and thumb. It is unclear how fine motor skills involving more than just two digits might be affected, especially given that loss of sensation from the hand affects many neurological patients, and impacts on everyday actions. To assess the functional consequences of haptic deficits on multi-digit grasp of objects, we studied the ability of three rare individuals with permanent large-fibre sensory loss involving the entire upper limb. All three reported difficulties in everyday manual actions (ABILHAND questionnaire). Their performance in a reach-grasp-lift task was compared to that of healthy controls. Twenty objects of varying shape, mass, opacity and compliance were used. In the reach-to-grasp phase, we found slower movement, larger grip aperture and less dynamic modulation of grip aperture in deafferented participants compared to controls. Hand posture during the lift phase also differed; deafferented participants often adopted hand postures that may have facilitated visual guidance, and/or reduced control complexity. For example, they would extend fingers that were not in contact with the object, or fold these fingers into the palm of the hand. Variability in hand postures was increased in deafferented participants, particularly for smaller objects. Our findings provide new insights into how the complex control required for whole hand actions is compromised by loss of haptic feedback, whose contribution is, thus, highlighted.
|Journal||Experimental Brain Research|
|Early online date||17 Jun 2019|
|Publication status||E-pub ahead of print - 17 Jun 2019|
- Grasp, Haptics, Human, Manipulation, Proprioception, Somatosensation