An EEG index of sensorimotor interhemispheric coupling after unilateral stroke: clinical and neurophysiological study

Floriana Pichiorri, Manuela Petti, Stefano Caschera, Laura Astolfi, Febo Cincotti, Donatella Mattia

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Brain connectivity has been employed to investigate on post-stroke recovery mechanisms and assess the effect of specific rehabilitation interventions. Changes in interhemispheric coupling after stroke have been related to the extent of damage in the corticospinal tract (CST) and thus, to motor impairment. In this study, we aimed at defining an index of interhemispheric connectivity derived from electroencephalography (EEG), correlated with CST integrity and clinical impairment. Thirty sub-acute stroke patients underwent clinical and neurophysiological evaluation: CST integrity was assessed by Transcranial Magnetic Stimulation and high-density EEG was recorded at rest. Connectivity was assessed by means of Partial Directed Coherence and the normalized Inter-Hemispheric Strength (nIHS) was calculated for each patient and frequency band on the whole network and in three sub-networks relative to the frontal, central (sensorimotor) and occipital areas. Interhemipheric coupling as expressed by nIHS on the whole network was significantly higher in patients with preserved CST integrity in beta and gamma bands. The same index estimated for the three sub-networks showed significant differences only in the sensorimotor area in lower beta, with higher values in patients with preserved CST integrity. The sensorimotor lower beta nIHS showed a significant positive correlation with clinical impairment. We propose an EEG-based connectivity index which is a measure of the interhemispheric cross-talking and correlates with functional motor impairment in subacute stroke patients. Such index could be employed to evaluate the effects of training aimed at re-establishing interhemispheric balance and eventually drive the design of future connectivity-driven rehabilitation interventions.

Original languageEnglish
Pages (from-to)158-163
Number of pages6
JournalEuropean Journal of Neuroscience
Volume47
Issue number2
DOIs
Publication statusE-pub ahead of print - Dec 15 2017

Fingerprint

Pyramidal Tracts
Electroencephalography
Stroke
Rehabilitation
Transcranial Magnetic Stimulation
Clinical Studies
Brain

Keywords

  • corticospinal tract
  • effective connectivity
  • interhemispheric communication
  • transcranial magnetic stimulation

ASJC Scopus subject areas

  • Neuroscience(all)

Cite this

An EEG index of sensorimotor interhemispheric coupling after unilateral stroke : clinical and neurophysiological study. / Pichiorri, Floriana; Petti, Manuela; Caschera, Stefano; Astolfi, Laura; Cincotti, Febo; Mattia, Donatella.

In: European Journal of Neuroscience, Vol. 47, No. 2, 15.12.2017, p. 158-163.

Research output: Contribution to journalArticle

@article{fffdb92e547044a296cb3a66adb9f0d4,
title = "An EEG index of sensorimotor interhemispheric coupling after unilateral stroke: clinical and neurophysiological study",
abstract = "Brain connectivity has been employed to investigate on post-stroke recovery mechanisms and assess the effect of specific rehabilitation interventions. Changes in interhemispheric coupling after stroke have been related to the extent of damage in the corticospinal tract (CST) and thus, to motor impairment. In this study, we aimed at defining an index of interhemispheric connectivity derived from electroencephalography (EEG), correlated with CST integrity and clinical impairment. Thirty sub-acute stroke patients underwent clinical and neurophysiological evaluation: CST integrity was assessed by Transcranial Magnetic Stimulation and high-density EEG was recorded at rest. Connectivity was assessed by means of Partial Directed Coherence and the normalized Inter-Hemispheric Strength (nIHS) was calculated for each patient and frequency band on the whole network and in three sub-networks relative to the frontal, central (sensorimotor) and occipital areas. Interhemipheric coupling as expressed by nIHS on the whole network was significantly higher in patients with preserved CST integrity in beta and gamma bands. The same index estimated for the three sub-networks showed significant differences only in the sensorimotor area in lower beta, with higher values in patients with preserved CST integrity. The sensorimotor lower beta nIHS showed a significant positive correlation with clinical impairment. We propose an EEG-based connectivity index which is a measure of the interhemispheric cross-talking and correlates with functional motor impairment in subacute stroke patients. Such index could be employed to evaluate the effects of training aimed at re-establishing interhemispheric balance and eventually drive the design of future connectivity-driven rehabilitation interventions.",
keywords = "corticospinal tract, effective connectivity, interhemispheric communication, transcranial magnetic stimulation",
author = "Floriana Pichiorri and Manuela Petti and Stefano Caschera and Laura Astolfi and Febo Cincotti and Donatella Mattia",
year = "2017",
month = "12",
day = "15",
doi = "10.1111/ejn.13797",
language = "English",
volume = "47",
pages = "158--163",
journal = "European Journal of Neuroscience",
issn = "0953-816X",
publisher = "Wiley-Blackwell",
number = "2",

}

TY - JOUR

T1 - An EEG index of sensorimotor interhemispheric coupling after unilateral stroke

T2 - clinical and neurophysiological study

AU - Pichiorri, Floriana

AU - Petti, Manuela

AU - Caschera, Stefano

AU - Astolfi, Laura

AU - Cincotti, Febo

AU - Mattia, Donatella

PY - 2017/12/15

Y1 - 2017/12/15

N2 - Brain connectivity has been employed to investigate on post-stroke recovery mechanisms and assess the effect of specific rehabilitation interventions. Changes in interhemispheric coupling after stroke have been related to the extent of damage in the corticospinal tract (CST) and thus, to motor impairment. In this study, we aimed at defining an index of interhemispheric connectivity derived from electroencephalography (EEG), correlated with CST integrity and clinical impairment. Thirty sub-acute stroke patients underwent clinical and neurophysiological evaluation: CST integrity was assessed by Transcranial Magnetic Stimulation and high-density EEG was recorded at rest. Connectivity was assessed by means of Partial Directed Coherence and the normalized Inter-Hemispheric Strength (nIHS) was calculated for each patient and frequency band on the whole network and in three sub-networks relative to the frontal, central (sensorimotor) and occipital areas. Interhemipheric coupling as expressed by nIHS on the whole network was significantly higher in patients with preserved CST integrity in beta and gamma bands. The same index estimated for the three sub-networks showed significant differences only in the sensorimotor area in lower beta, with higher values in patients with preserved CST integrity. The sensorimotor lower beta nIHS showed a significant positive correlation with clinical impairment. We propose an EEG-based connectivity index which is a measure of the interhemispheric cross-talking and correlates with functional motor impairment in subacute stroke patients. Such index could be employed to evaluate the effects of training aimed at re-establishing interhemispheric balance and eventually drive the design of future connectivity-driven rehabilitation interventions.

AB - Brain connectivity has been employed to investigate on post-stroke recovery mechanisms and assess the effect of specific rehabilitation interventions. Changes in interhemispheric coupling after stroke have been related to the extent of damage in the corticospinal tract (CST) and thus, to motor impairment. In this study, we aimed at defining an index of interhemispheric connectivity derived from electroencephalography (EEG), correlated with CST integrity and clinical impairment. Thirty sub-acute stroke patients underwent clinical and neurophysiological evaluation: CST integrity was assessed by Transcranial Magnetic Stimulation and high-density EEG was recorded at rest. Connectivity was assessed by means of Partial Directed Coherence and the normalized Inter-Hemispheric Strength (nIHS) was calculated for each patient and frequency band on the whole network and in three sub-networks relative to the frontal, central (sensorimotor) and occipital areas. Interhemipheric coupling as expressed by nIHS on the whole network was significantly higher in patients with preserved CST integrity in beta and gamma bands. The same index estimated for the three sub-networks showed significant differences only in the sensorimotor area in lower beta, with higher values in patients with preserved CST integrity. The sensorimotor lower beta nIHS showed a significant positive correlation with clinical impairment. We propose an EEG-based connectivity index which is a measure of the interhemispheric cross-talking and correlates with functional motor impairment in subacute stroke patients. Such index could be employed to evaluate the effects of training aimed at re-establishing interhemispheric balance and eventually drive the design of future connectivity-driven rehabilitation interventions.

KW - corticospinal tract

KW - effective connectivity

KW - interhemispheric communication

KW - transcranial magnetic stimulation

UR - http://www.scopus.com/inward/record.url?scp=85040605093&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85040605093&partnerID=8YFLogxK

U2 - 10.1111/ejn.13797

DO - 10.1111/ejn.13797

M3 - Article

AN - SCOPUS:85040605093

VL - 47

SP - 158

EP - 163

JO - European Journal of Neuroscience

JF - European Journal of Neuroscience

SN - 0953-816X

IS - 2

ER -