Modulation of the ~20‐Hz motor‐cortex rhythm to passive movement and tactile stimulation. Issue 5 (31st March 2015)

• Record Type: Journal Article
• Authors: Parkkonen, Eeva; Laaksonen, Kristina; Piitulainen, Harri; Parkkonen, Lauri; Forss, Nina
• Is Part Of: Brain and behavior. Volume 5:Issue 5(2015:May)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2015-03-31
• Subjects: Neurology -- Periodicals; Neurosciences -- Periodicals; Psychology -- Periodicals; Psychiatry -- Periodicals; 616.8005
• DOI: 10.1002/brb3.328
• Languages: English
• ISSNs: 2162-3279

Abstract

<abstract abstract-type="main" id="brb3328-abs-0001"> <title>Abstract</title> <sec id="brb3328-sec-0001" sec-type="section"> <title>Background</title> <p>Integration of afferent somatosensory input with motor‐cortex output is essential for accurate movements. Prior studies have shown that tactile input modulates motor‐cortex excitability, which is reflected in the reactivity of the ~20‐Hz motor‐cortex rhythm. ~20‐Hz rebound is connected to inhibition or deactivation of motor cortex whereas suppression has been associated with increased motor cortex activity. Although tactile sense carries important information for controlling voluntary actions, proprioception likely provides the most essential feedback for motor control.</p> </sec> <sec id="brb3328-sec-0002" sec-type="section"> <title>Methods</title> <p>To clarify how passive movement modulates motor‐cortex excitability, we studied with magnetoencephalography (MEG) the amplitudes and peak latencies of suppression and rebound of the ~20‐Hz rhythm elicited by tactile stimulation and passive movement of right and left index fingers in 22 healthy volunteers.</p> </sec> <sec id="brb3328-sec-0003" sec-type="section"> <title>Results</title> <p>Passive movement elicited a stronger and more robust ~20‐Hz rebound than tactile stimulation. In contrast, the suppression amplitudes did not differ between the two stimulus types.</p> </sec> <sec id="brb3328-sec-0004" sec-type="section"> <title>Conclusion</title> <p>Our findings suggest that suppression and rebound represent activity of two functionally distinct neuronal populations. The ~20‐Hz rebound to passive movement could be a suitable tool to study the functional state of the motor cortex both in healthy subjects and in patients with motor disorders.</p> </sec> </abstract>