caa a22 4500 445353910 CHVBK 20180317142853.0 cr unu---uuuuu 170323e20110701xx s 000 0 eng 10.1007/s00221-011-2728-6 doi (NATIONALLICENCE)springer-10.1007/s00221-011-2728-6 The impact of light fingertip touch on haptic cortical processing during a standing balance task [Elektronische Daten] [David Bolton, William McIlroy, W. Richard Staines] Availability of fingertip touch onto a stable surface reduces body sway for subjects standing with eyes closed. This is largely associated with sensory feedback from the fingertip when mechanical load is limited. Here, it is possible that the central nervous system facilitates cortical sensory processing to augment feedback to control upright stance. To test this, we compared cortical sensory excitability between tasks with and without light finger touch while standing. Subjects stood in tandem on a force plate with eyes closed while lightly touching a stable surface with the index finger. This was, in two different studies, compared to: (1) no haptic contact or (2) light touch on an object not referenced to balance. Throughout testing, the median nerve was stimulated and electroencephalography was used to measure somatosensory evoked potentials (SEPs). As expected, availability of stable light touch reduced medial-lateral COP sway. Peak amplitudes for SEP components revealed reduced P100 (48%), but increased P50 (31%), N140 (80%), and P200 (20%) during stable touch versus no touch. The modulation of P50 and N140 was no longer present when comparing stable to control (touch), which suggested that attending to touch on either surface, regardless of stability reference, accounted for these changes. Conversely, P200 was increased (19%) when touching the stable surface. Our data show SEP modulation during a standing balance task related to hand contact. Facilitation of P200 in particular may indicate task-specific regulation of the cortical representation of fingertip afferent input when it is relevant to providing stable cues for static balance control. Springer-Verlag, 2011 Balance nationallicence Haptic nationallicence EEG nationallicence SEP nationallicence Somatosensation nationallicence EMG nationallicence Bolton David Department of Kinesiology, University of Waterloo, 200 University Avenue W, N2L 3G1, Waterloo, ON, Canada aut McIlroy William Department of Kinesiology, University of Waterloo, 200 University Avenue W, N2L 3G1, Waterloo, ON, Canada aut Richard Staines W. Department of Kinesiology, University of Waterloo, 200 University Avenue W, N2L 3G1, Waterloo, ON, Canada aut Experimental Brain Research Springer-Verlag 212/2(2011-07-01), 279-291 0014-4819 212:2<279 2011 212 221 https://doi.org/10.1007/s00221-011-2728-6 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00221-011-2728-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Bolton David Department of Kinesiology, University of Waterloo, 200 University Avenue W, N2L 3G1, Waterloo, ON, Canada aut NATIONALLICENCE 700 1- McIlroy William Department of Kinesiology, University of Waterloo, 200 University Avenue W, N2L 3G1, Waterloo, ON, Canada aut NATIONALLICENCE 700 1- Richard Staines W. Department of Kinesiology, University of Waterloo, 200 University Avenue W, N2L 3G1, Waterloo, ON, Canada aut NATIONALLICENCE 773 0- Experimental Brain Research Springer-Verlag 212/2(2011-07-01), 279-291 0014-4819 212:2<279 2011 212 221 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer