Speech dynamics are coded in the left motor cortex in fluent speakers but not in adults who stutter. Published in BRAIN
Speaking fluently can be challenging even for a political or mathematical genius such as Winston Churchill and Alan Turing, as recently illustrated for the latter in the movie „The Imitation Game“. It demonstrates obvious but temporary breakdowns in speech flow. New research has now shown that the way how speech motor areas of the brain prepare for intended speech is abnormal in adults suffering from persistent developmental stuttering, as reported in this month in Brain.
Original publication: Speech dynamics are coded in the left motor cortex in fluent speakers but not in adults who stutter. Neef NE, Hoang TN, Neef A, Paulus W, Sommer M. Brain. 2015 Mar;138 (Pt 3):712-25. PMID: 25595146
Moving the right leg or arm requires the activation of the motor area in the left hemisphere of the brain. Conversely, orofacial midline muscles such as tongue, lips, jaw, and vocal folds are bilaterally controlled – both hemispheres innervate both sides of the articulatory apparatus. For this reason it would be plausible to expect that operating neurons are similarly excited in both hemispheres during speaking. But this is not the case.
Drs. Nicole Neef and Martin Sommer from the University Medical Center Göttingen, together with Dr. Andreas Neef from the Max Planck Institute for Dynamics and Self-Organization, Göttingen, used a technique with high temporal resolution and a direct functional read-out: they stimulated the cortical area that controls the tongue with brief electromagnetical pulses while participating subjects were speaking. The stimulation efficiency was monitored with electrodes on the tongue.
This allowed them, for the first time, to track changes in the local cortical excitability that accompanied the transition between speech gestures. In control subjects, excitability in the left hemisphere motor area increased during this transition, indicating a speech motor preparation confined to the left brain hemisphere. In adults who stutter, this pattern was lacking on the left side. The more severe individuals stuttered the more impaired was the speech motor preparation in the left hemisphere.
These results integrate structural and neurophysiological findings into a plausible model of speech pathophysiology in persistent developmental stuttering. They pinpoint the left primary motor cortex and its interconnected areas as key players in the generation of fluent speech, and will pave the way to directly modulating the excitability of these areas to influence speech fluency.
Universitätsmedizin Göttingen, Georg-August-Universität
Klinik für Klinische Neurophysiologie
Prof. Dr. Martin Sommer
Phone: +49 (0) 551 / 39-8463
Robert-Koch-Straße 40, 37075 Göttingen
Stefan Weller | idw - Informationsdienst Wissenschaft
First time-lapse footage of cell activity during limb regeneration
25.10.2016 | eLife
Phenotype at the push of a button
25.10.2016 | Institut für Pflanzenbiochemie
Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.
This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
25.10.2016 | Earth Sciences
25.10.2016 | Power and Electrical Engineering
25.10.2016 | Process Engineering