Research article summary (published 11 Apr 2002):

Reduced intracortical inhibition and facilitation of corticospinal neurons in musicians.

Full Abstract

Interhemispheric inhibition between motor cortices is reduced in musicians. In the present study we have assessed intracortical inhibition (ICI) and facilitation (ICF) within ipsilateral motor cortex in 15 musicians and 15 non-musician controls. Transcranial magnetic stimulation (TMS) was used to elicit muscle evoked potentials (MEPs) from left first dorsal interosseous (FDI) muscle at rest, and during voluntary index finger abduction (0.5 N). Paired TMS with subthreshold conditioning was used to test early ICI with interstimulus intervals (ISIs) 1-5 ms, and ICF with ISIs 8-15 ms. Suprathreshold conditioning was used to test late ICI with ISIs 100-200 ms. TMS thresholds were similar in musicians and controls both at rest and with weak voluntary activation of FDI, indicating that postsynaptic excitability of corticospinal neurons was similar in both groups. ICI was less effective in musicians with FDI at rest and active, but only with an ISI of 3 ms. ICF was less effective in musicians under both rest and active conditions, and this was independent of ISI. There were no differences in late ICI between musicians and controls. We conclude that ICI and ICF circuits which are activated by weak TMS have less influence on corticospinal neuron excitability in musicians. Because of the dependence on ISI, the most likely explanation for the reduced ICI in musicians is an alteration of the interaction between the ICI circuit and neural elements responsible for the later I-waves evoked in corticospinal neurons by TMS. Excitability of the neural elements producing early and late ICI is not altered in musicians. Reduced ICF in musicians could be due to reduced excitability of neurons responsible for ICF, or an altered balance of excitatory inputs to corticospinal neurons which favours neurons that are not acted upon by the ICF circuit. The reduced influence of ICI and ICF circuits on corticospinal neuron excitability in musicians is likely to reflect a training-induced adaptation. It is not clear at present whether these differences represent an adaptive change related to their extraordinary control of finger movements, or alternatively a maladaptive change induced by "overuse" of the hands from extensive training.

Author information

Author/s: Nordstrom, Michael A (MA); Butler, Sophie L (SL);

Affiliation: Department of Physiology, University of Adelaide, Adelaide, SA 5005, Australia. michael.nordstrom(-atsign-)adelaide.edu.au

Journal and publication information

Publication Type: Journal Article; Research Support, Non-U.S. Gov't

Journal: Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale (Exp Brain Res), published in Germany. (Language: eng)

Reference: 2002-Jun; vol 144 (issue 3) : pp 336-42

Dates: Created 2002/05/21; Completed 2002/09/04; Revised 2009/11/11;

PMID: 12021815, status: MEDLINE (last retrieval date: 11/11/2009, IMS Date: )

Sourced from the National Library of Medicine. Abstract text and other information may be subject to copyright.

External Links for this article
(including full text providers, if available):

Click Electronic Full-text Provider Links to see options for finding the electronic full text links to this article. Note there may be a subscription or fee required for access to the full text. See our FAQ for information on finding FREE full text articles.

This article may also be located in paper journal collections available in many libraries. Use the Journal and Publication Information above to find the full article.

MeSH headings (categories)

This article was linked to the MESH Headings shown below.

Adolescent Adult Conditioning (Psychology) - physiology Electric Stimulation Evoked Potentials, Motor - physiology Excitatory Postsynaptic Potentials - physiology Female Functional Laterality - physiology Hand - innervation; physiology Humans Magnetics Male

Male Motor Cortex - physiology Motor Neurons - physiology Motor Skills - physiology Muscle Contraction - physiology Muscle, Skeletal - innervation; physiology Music Neural Inhibition - physiology Pyramidal Cells - physiology Pyramidal Tracts - physiology Reaction Time - physiology Spinal Cord - physiology

Related articles

These are the highest related articles currently in the database:

• Factors influencing cortical silent period: optimized stimulus location, intensity and muscle contraction. 21 Dec 2007
• Modulation of long-interval intracortical inhibition and the silent period by voluntary contraction. 16 May 2007
• Asymmetric facilitation from repeated paired magnetic stimulation of human motor cortex. 3 Mar 2008
• Muscle-specific variations in use-dependent crossed-facilitation of corticospinal pathways mediated by transcranial direct current (DC) stimulation. 17 Jun 2008
• Noninvasive stimulation of human corticospinal axons innervating leg muscles. 26 May 2008
• Trial-to-trial size variability of motor-evoked potentials. A study using the triple stimulation technique. 28 Jan 2008
• Modulation of corticospinal excitability during lengthening and shortening contractions in the first dorsal interosseus muscle of humans. 22 Oct 2006
• Transcallosal sensorimotor integration: effects of sensory input on cortical projections to the contralateral hand. 28 Jan 2006
• Repetitive paired-pulse TMS at I-wave periodicity markedly increases corticospinal excitability: a new technique for modulating synaptic plasticity. 30 Nov 2005
• Induction of plasticity in the dominant and non-dominant motor cortices of humans. 23 Feb 2006

See 100+ related articles.

Related Article Map

Legend: - FREE Full text Article. - Abstract only. - Title only. More help.

See a large map of 100+ related articles.