Enhanced mirroring upon mutual gaze: Multimodal evidence from TMS-assessed corticospinal excitability and the EEG mu rhythm

Mapping Intimacies ◽

10.1101/2020.03.24.995696 ◽

2020 ◽

Author(s):

Jellina Prinsen ◽

Kaat Alaerts

Keyword(s):

Action Observation ◽

Hand Movement ◽

Stimulus Person ◽

Eye Contact ◽

Mirror System ◽

Mu Rhythm ◽

Mu Suppression ◽

Motor Cortex Excitability ◽

System Functioning ◽

Averted Gaze

AbstractEye-to-eye contact is a salient cue for regulating everyday social interaction and communication. Previous research has demonstrated that direct eye contact between actor and observer specifically enhances the ‘mirroring’ of others’ actions in the observer, as measured by transcranial magnetic stimulation (TMS)-induced motor evoked potentials (MEPs; an index of motor cortex excitability during action observation). However, it remains unknown whether other markers of mirror system activation, such as suppression of the EEG mu rhythm (i.e. attenuation of neural oscillations in the 8-13 Hz frequency band over the sensorimotor strip), are also susceptible to perceived eye contact. In the current study, a multimodal approach was adopted to assess both TMS-induced MEPs and EEG mu suppression (in separate sessions), while 32 participants (20 men; mean age: 24;8 years) observed a simple hand movement in combination with direct or averted gaze from the live stimulus person. Both indices of mirror system functioning were significantly modulated by perceived eye gaze; showing a significant increase in MEP amplitude and a significant attenuation of the mu rhythm when movement observation was accompanied with direct compared to averted gaze. Importantly, while inter-individual differences in absolute MEP and mu suppression scores were not significantly related, a significant association was identified between gaze-related changes in MEP responses and mu suppression. As such, it appears that while the neurophysiological substrates underlying mu suppression and TMS-induced MEP responses differ, both are similarly affected by the modulatory impact of gaze-related cues. In sum, our results suggest that both EEG mu rhythm and TMS-induced MEPs are sensitive to the social relevance of the observed actions, and that a similar neural substrate may drive gaze-related changes in these distinct markers of mirror system functioning.

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Enhanced mirroring upon mutual gaze: multimodal evidence from TMS-assessed corticospinal excitability and the EEG mu rhythm

Scientific Reports ◽

10.1038/s41598-020-77508-x ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Jellina Prinsen ◽

Kaat Alaerts

Keyword(s):

Motor Evoked Potentials ◽

Eye Gaze ◽

Action Observation ◽

Hand Movement ◽

Eye Contact ◽

Mu Rhythm ◽

Social Relevance ◽

Mu Suppression ◽

Gating Mechanism ◽

Averted Gaze

AbstractPrevious research has demonstrated that eye contact between actor and observer specifically enhances the ‘mirroring’ of others’ actions, as measured by transcranial magnetic stimulation (TMS)-induced motor evoked potentials (MEPs). However, it remains unknown whether other markers of mirror system activation, such as suppression of the EEG mu rhythm (8–13 Hz) over the sensorimotor strip, are also susceptible to perceived eye contact. Here, both TMS-induced MEPs and EEG mu suppression indices were assessed (in separate sessions) while 32 participants (mean age: 24y; 8m) observed a simple hand movement combined with direct or averted gaze from the actor. Both measures were significantly modulated by perceived eye gaze during action observation; showing an increase in MEP amplitude and an attenuation of the mu rhythm during direct vs. averted gaze. Importantly, while absolute MEP and mu suppression scores were not related, a significant association was identified between gaze-related changes in MEPs and mu suppression, indicating that both measures are similarly affected by the modulatory impact of gaze cues. Our results suggest that although the neural substrates underlying TMS-induced MEPs and the EEG mu rhythm may differ, both are sensitive to the social relevance of the observed actions, which might reflect a similar neural gating mechanism.

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EEG-Based Evidence of Mirror Neuron Activity from App-Mediated Stroke Patient Observation

Medicina ◽

10.3390/medicina57090979 ◽

2021 ◽

Vol 57 (9) ◽

pp. 979

Author(s):

Jin-Cheol Kim ◽

Hyun-Min Lee

Keyword(s):

Daily Life ◽

Mirror Neuron System ◽

Action Observation ◽

Mirror Neuron ◽

Neuron Activity ◽

Significant Activity ◽

Mu Rhythm ◽

Neuron System ◽

Mu Suppression ◽

Observation Training

Background and Objectives: The mirror neuron system in the sensorimotor region of the cerebral cortex is equally activated during both action observation and execution. Action observation training mimics the functioning of the mirror neuron system, requiring patients to watch and imitate the actions necessary to perform activities of daily living. StrokeCare is a user-friendly application based on the principles of action observation training, designed to assist people recovering from stroke. Therefore, when observing the daily life behavior provided in the StrokeCare app, whether the MNS is activated and mu inhibition appears. Materials and Methods: We performed electroencephalography (EEG) on 24 patients with chronic stroke (infarction: 11, hemorrhage: 13) during tasks closely related to daily activities, such as dressing, undressing, and walking. The StrokeCare app provided action videos for patients to watch. Landscape imagery observation facilitated comparison among tasks. We analyzed the mu rhythm from the C3, CZ, and C4 regions and calculated the mean log ratios for comparison of mu suppression values. Results: The EEG mu power log ratios were significantly suppressed during action observation in dressing, undressing, walking, and landscape conditions, in decreasing order. However, there were no significant activity differences in the C3, C4 and CZ regions. The dressing task showed maximum suppression after a color spectrum was used to map the relative power values of the mu rhythm for each task. Conclusions: These findings reveal that the human mirror neuron system was more strongly activated during observation of actions closely related to daily life activities than landscape images.

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Attention Modulates Motor Cortex Activation During Action Observation: An EEG Mu Rhythm Study

PsycEXTRA Dataset ◽

10.1037/e512682013-498 ◽

2007 ◽

Author(s):

Stefanie Schuch ◽

Andrew P. Bayliss ◽

Steven P. Tipper

Keyword(s):

Motor Cortex ◽

Action Observation ◽

Mu Rhythm

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Calculation and Analysis of Microstate Related to Variation in Executed and Imagined Movement of Force of Hand Clenching

Computational Intelligence and Neuroscience ◽

10.1155/2018/9270685 ◽

2018 ◽

Vol 2018 ◽

pp. 1-15 ◽

Cited By ~ 1

Author(s):

Yunfa Fu ◽

Jian Chen ◽

Xin Xiong

Keyword(s):

Grip Force ◽

Activity Patterns ◽

Hand Movement ◽

Local Maximum ◽

Topographic Map ◽

Mu Rhythm ◽

Global Field Power ◽

Frequency Bands ◽

Microstate Analysis ◽

Imagined Movement

Objective. In order to investigate electroencephalogram (EEG) instantaneous activity states related to executed and imagined movement of force of hand clenching (grip force: 4 kg, 10 kg, and 16 kg), we utilized a microstate analysis in which the spatial topographic map of EEG behaves in a certain number of discrete and stable global brain states. Approach. Twenty subjects participated in EEG collection; the global field power of EEG and its local maximum were calculated and then clustered using cross validation and statistics; the 4 parameters of each microstate (duration, occurrence, time coverage, and amplitude) were calculated from the clustering results and statistically analyzed by analysis of variance (ANOVA); finally, the relationship between the microstate and frequency band was analyzed. Main Results. The experimental results showed that all microstates related to executed and imagined grip force tasks were clustered into 3 microstate classes (A, B, and C); these microstates generally transitioned from A to B and then from B to C. With the increase of the target value of executed and imagined grip force, the duration and time coverage of microstate B gradually decreased, while these parameters of microstate C gradually increased. The occurrence times of microstate B and C related to executed grip force were significantly more than those related to imagined grip force; furthermore, the amplitudes of these 3 microstates related to executed grip force were significantly greater than those related to imagined grip force. The correlation coefficients between the microstates and the frequency bands indicated that the microstates were correlated to mu rhythm and beta frequency bands, which are consistent with event-related desynchronization/synchronization (ERD/ERS) phenomena of sensorimotor rhythm. Significance. It is expected that this microstate analysis may be used as a new method for observing EEG instantaneous activity patterns related to variation in executed and imagined grip force and also for extracting EEG features related to these tasks. This study may lay a foundation for the application of executed and imagined grip force training for rehabilitation of hand movement disorders in patients with stroke in the future.

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Mirror-neuron system recruitment by action observation: Effects of focal brain damage on mu suppression

NeuroImage ◽

10.1016/j.neuroimage.2013.10.019 ◽

2014 ◽

Vol 87 ◽

pp. 127-137 ◽

Cited By ~ 31

Author(s):

Silvi Frenkel-Toledo ◽

Shlomo Bentin ◽

Anat Perry ◽

Dario G. Liebermann ◽

Nachum Soroker

Keyword(s):

Brain Damage ◽

Mirror Neuron System ◽

Action Observation ◽

Mirror Neuron ◽

Neuron System ◽

Mu Suppression

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Motor system recruitment during action observation: No correlation between mu-rhythm desynchronization and corticospinal excitability

PLoS ONE ◽

10.1371/journal.pone.0207476 ◽

2018 ◽

Vol 13 (11) ◽

pp. e0207476 ◽

Cited By ~ 6

Author(s):

Olivia M. Lapenta ◽

Elisabetta Ferrari ◽

Paulo S. Boggio ◽

Luciano Fadiga ◽

Alessandro D’Ausilio

Keyword(s):

Motor System ◽

Action Observation ◽

Corticospinal Excitability ◽

Mu Rhythm

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Eye contact during joint attention with a humanoid robot modulates oscillatory brain activity

10.31234/osf.io/eam3d ◽

2021 ◽

Author(s):

Kyveli Kompatsiari ◽

Francesco Bossi ◽

Agnieszka Wykowska

Keyword(s):

Joint Attention ◽

Humanoid Robot ◽

Brain Activity ◽

Eye Contact ◽

Mu Rhythm ◽

Brain Response ◽

Functional Roles ◽

Gaze Cueing ◽

Human Partner ◽

Oscillatory Brain Activity

Eye contact established by a human partner has been shown to affect various cognitive processes of the receiver. However, little is known about humans’ responses to eye contact established by a humanoid robot. Here, we aimed at examining humans’ oscillatory brain response to eye contact with a humanoid robot. Eye contact (or lack thereof) was embedded in a gaze cueing task and preceded the phase of gaze-related attentional orienting. In addition to examining the effect of eye contact on the recipient, we also tested its impact on gaze cueing effects. Results showed that participants rated eye contact as more engaging and responded with higher desynchronization of alpha-band activity in left fronto-central and central electrode clusters when the robot established eye contact with them, compared to no eye contact condition. However, eye contact did not modulate gaze cueing effects. The results are interpreted in terms of the functional roles involved in alpha central rhythms (potentially interpretable also as mu rhythm), including joint attention and engagement in social interaction.

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