Open AccessUnderstanding the link between somatosensory temporal discrimination and movement execution in healthy subjects
Author(s) -
Conte Antonella,
Belvisi Daniele,
Manzo Nicoletta,
Bologna Matteo,
Barone Francesca,
Tartaglia Matteo,
Upadhyay Neeraj,
Berardelli Alfredo
Publication year - 2016
Publication title -
physiological reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.918
H-Index - 39
ISSN - 2051-817X
DOI - 10.14814/phy2.12899
Subject(s) - somatosensory system , index finger , transcranial magnetic stimulation , neuroscience , movement (music) , psychology , primary motor cortex , stimulation , ctbs , physical medicine and rehabilitation , motor cortex , medicine , audiology , anatomy , philosophy , aesthetics
The somatosensory temporal discrimination threshold ( STDT ) is the shortest interval at which an individual recognizes paired stimuli as separate in time. We investigated whether and how voluntary movement modulates STDT in healthy subjects. In 17 healthy participants, we tested STDT during voluntary index‐finger abductions at several time‐points after movement onset and during motor preparation. We then tested whether voluntary movement‐induced STDT changes were specific for the body segment moved, depended on movement kinematics, on the type of movement or on the intensity for delivering paired electrical stimuli for STDT . To understand the mechanisms underlying STDT modulation, we also tested STDT during motor imagery and after delivering repetitive transcranial magnetic stimulation to elicit excitability changes in the primary somatosensory cortex (S1). When tested on the moving hand at movement onset and up to 200 msec thereafter, STDT values increased from baseline, but during motor preparation remained unchanged. STDT values changed significantly during fast and slow index‐finger movements and also, though less, during passive index‐finger abductions, whereas during tonic index‐finger abductions they remained unchanged. STDT also remained unchanged when tested in body parts other than those engaged in movement and during imagined movement. Nor did testing STDT at increased intensity influence movement‐induced STDT changes. The cTBS ‐induced S1 cortical changes left movement‐induced STDT changes unaffected. Our findings suggest that movement execution in healthy subjects may alter STDT processing.