Format

Send to

Choose Destination
Eur J Neurosci. 2017 May;45(9):1200-1211. doi: 10.1111/ejn.13429. Epub 2016 Oct 31.

The rhythm of the executive gate of speech: subthalamic low-frequency oscillations increase during verbal generation.

Author information

1
Institute of Clinical Neuroscience and Medical Psychology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Moorenstr. 5, 40225, Duesseldorf, Germany.
2
Department of Neurology, Center for Movement Disorders and Neuromodulation, Medical Faculty, Heinrich-Heine-University Düsseldorf, Moorenstr. 5, 40225, Duesseldorf, Germany.
3
Department of Stereotactic and Functional Neurosurgery, Center for Movement Disorders and Neuromodulation, Medical Faculty, Heinrich-Heine-University Düsseldorf, Duesseldorf, Germany.

Abstract

We investigated neurophysiological mechanisms of subthalamic nucleus involvement in verbal fluency through a verbal generation task. The subthalamic nucleus is thought to act as a behavioural go/no-go instance by means of oscillatory communication in the theta band with the prefrontal cortex. Because subthalamic alpha-theta frequency stimulation has been shown to exert beneficial effects on verbal fluency in Parkinson's disease, we hypothesized that an alpha-theta oscillatory network involving the subthalamic nucleus underlies verbal generation task performance as a gating instance for speech execution. Postoperative subthalamic local field potential recordings were performed during a verbal generation compared to a control task. Time-frequency analysis revealed a significant alpha-theta power increase and enhanced alpha-theta coherence between the subthalamic nucleus and the frontal surface EEG during the verbal generation task. Beta and gamma oscillations were not significantly modulated by the task. Power increase significantly correlated with verbal generation performance. Our results provide experimental evidence for local alpha-theta oscillatory activity in the subthalamic nucleus and coherence to frontal associative areas as a neurophysiological mechanism underlying a verbal generation task. Thus, verbal fluency improvement during subthalamic alpha-theta stimulation in Parkinson's disease is likely due to an enhancement of alpha-theta oscillatory network activity. Alpha-theta oscillations can be interpreted as the rhythmic gating signature in a speech executing subthalamic-prefrontal network.

KEYWORDS:

executive function; local field potentials; subthalamic nucleus; verbal fluency

PMID:
27718535
DOI:
10.1111/ejn.13429
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center