Tactile gating in a reaching and grasping task reveals sensory and motor interactions affecting tactile sensitivity of the moving upper limb
department or school: Graduate Studies, College of (Okanagan)
data provider: DSpace
degree campus: UBCO
creator: Colino, Francisco
issued: 2015-04-28T15:46:43Z
issued: 2015
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: A multitude of events bombard our sensory systems at every moment of our lives. Thus, it is important for the sensory cortex to gate unimportant events. Tactile suppression is a well-known phenomenon defined as a reduced ability to detect tactile events on the skin before and during movement. Previous experiments (e.g., Chapman et al., 1987) found detection rates decrease just prior to and during finger abduction, and decrease according to the proximity of the tactile event to the moving effector. However, there is no consensus regarding the cause of tactile gating. Previous work debated between centrally- vs. peripherally generated mechanisms causing tactile gating under different circumstances resulting in a reasonably good understanding of contributing neural networks. The present dissertation examined how tactile detection changes during a reach to grasp task. In a series of experiments, participants were asked to reach and grasp a cylinder. Tactors were attached to the index finger, the fifth digit and the forearm of both the right and left arm and vibrated at various epochs relative to an imperative “go” tone. These stimulation times were then renormalized post-hoc relative to movement onset. Movement performance was recorded using an infrared camera system tracking infrared emitting diodes. Results showed that detection rates at the forearm decreased before movement onset; whereas at the right index finger, right fifth digit and at the left index finger, left fifth digit and forearm sites no such reduction was observed (participants only moved the right upper limb). These results indicate that the task affects gating dynamics in a temporally- and contextually-dependent manner and implies that feedforward motor planning processes can modify sensory signals shifting the response criterion so that the likeliest response is negative.
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/52975
note: TACTILE GATING IN A REACHING AND GRASPING TASK REVEALS SENSORY AND MOTOR INTERACTIONS AFFECTING TACTILE SENSITIVITY OF THE MOVING UPPER LIMB by Francisco Colino B.P.H.E., The University of Toronto, 2008 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE COLLEGE OF GRADUATE STUDIES (Interdisciplinary Studies) THE UNIVERSITY OF BRITISH COLUMBIA (Okanagan) April 2015 © Francisco Colino, 2015 ii Abstract A multitude of events bombard our sensory systems at every moment of our lives. Thus, it is important for the sensory cortex to gate unimportant events. Tactile suppression is a well-known phenomenon defined as a reduced ability to detect tactile events on the skin before and during movement. Previous experiments (e.g., Chapman et al., 1987) found detection rates decrease just prior to and during finger abduction, and decrease according to the proximity of the tactile event to the moving effector. However, there is no consensus regarding the cause of tactile gating. Previous work debated between centrally- vs. peripherally generated mechanisms causing tactile gating under different circumstances resulting in a reasonably good understanding of contributing neural networks. The present dissertation examined how tactile detection changes during a reach to grasp task. In a series of experiments, participants were asked to reach and grasp a cylinder. Tactors were attached to the index finger, the fifth digit and the forearm of both the right and left arm and vibrated at various epochs relative to an imperative “go” tone. These stimulation times were then renormalized post-hoc relative to movement onset. Movement performance was recorded using an infrared camera system tracking infrared emitting diodes. Results showed that detection rates at the forearm decreased before movement onset; whereas at the right index finger, right fifth digit and at the left index finger, left fifth digit and forearm sites no such reduction …
has type: Thesis/Dissertation
date issued: 2015-05
is shown at: 10.14288/1.0074435
language: eng
degree discipline: Interdisciplinary Studies
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivs 2.5 Canada
rights URI: http://creativecommons.org/licenses/by-nc-nd/2.5/ca/
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/52975