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Controlled assessment of functional cortical networks is an unmet need in the clinical research of noncooperative subjects, such as infants. We developed an automated, pneumatic stimulation method to actuate naturalistic movements of an infant’s hand, as well as an analysis pipeline for assessing the elicited electroencephalography (EEG) responses and related cortical networks. Twenty newborn infants with perinatal asphyxia were recruited, including 7 with mild-to-moderate hypoxic–ischemic encephalopathy (HIE). Statistically significant corticokinematic coherence (CKC) was observed between repetitive hand movements and EEG in all infants, peaking near the contralateral sensorimotor cortex. CKC was robust to common sources of recording artifacts and to changes in vigilance state. A wide recruitment of cortical networks was observed with directed phase transfer entropy, also including areas ipsilateral to the stimulation. The extent of such recruited cortical networks was quantified using a novel metric, Spreading Index, which showed a decrease in 4 (57%) of the infants with HIE. CKC measurement is noninvasive and easy to perform, even in noncooperative subjects. The stimulation and analysis pipeline can be fully automated, including the statistical evaluation of the cortical responses. Therefore, the CKC paradigm holds great promise as a scientific and clinical tool for controlled assessment of functional cortical networks.

The Rolandic beta rhythm, at ∼20 Hz, is generated in the somatosensory and motor cortices and is modulated by motor activity and sensory stimuli, causing a short lasting suppression that is followed by a rebound of the beta rhythm. The rebound reflects inhibitory changes in the primary sensorimotor (SMI) cortex, and thus it has been used as a biomarker to follow the recovery of patients with acute stroke. The longitudinal stability of beta rhythm modulation is a prerequisite for its use in long-term follow-ups. We quantified the reproducibility of beta rhythm modulation in healthy subjects in a 1-year-longitudinal study both for MEG and EEG at

Collaboration between disciplines is necessary when research questions cannot be answered within a single discipline. Joining of forces can produce results that neither discipline could provide alone. Here we exemplify collaboration between a ceramic craft researcher and three neuroscientists working in the field of human brain imaging. In our case study of clay throwing, the researcher–practitioner’s eye gaze, muscular activity and hand acceleration were recorded online, synchronized with video and thermal-camera recordings. We describe the experimental setting and discuss, besides the possible future interests in this kind of research, also the different levels of collaborative work between disciplines. We found that the monitoring methods worked well in the naturalistic setting in a ceramic studio, providing some new perspectives into the craft practice. For neuroscientists, clay throwing – involving accurate sensorimotor hand control, haptics and eye–hand coordination – provides an attractive setup to extend previous neuroscientific and behavioural findings in strictly controlled laboratory experiments into naturalistic situations. The applied monitoring devices might allow practitioner–researchers in crafts to become aware of unconscious steps in the making process. The applied methods could also help to accumulate general craft-making knowledge and build related theory.

Funding Information: Data and code are available on the Open Science Framework (OSF) at the following link: https://osf.io/4rmex/?view_only=7d17c2334ace4a0d83087bddf2a64a68. Scott Mongold, Thomas Legrand, and Mathieu Bourguignon were supported by the Fonds de la Recherche Scientifique (F.R.S.-FNRS, Brussels, Belgium; grant MIS F.4504.21). Harri Piitulainen was supported by the Academy of Finland (grants 266133, 296240, 326988, 327288 and 311877) including “Brain changes across the life-span” profiling funding to University of Jyväskylä. We thank Helge Kainulainen and Ronny Schreiber at Aalto NeuroImaging for providing technical help and the force sensor system for the study. We thank Riitta Hari for her participation in the initial study. Funding Information: Scott Mongold, Thomas Legrand, and Mathieu Bourguignon were supported by the Fonds de la Recherche Scientifique (F.R.S.-FNRS, Brussels, Belgium; grant MIS F.4504.21 ). Harri Piitulainen was supported by the Academy of Finland (grants 266133 , 296240, 326988 , 327288 and 311877 ) including “Brain changes across the life-span” profiling funding to University of Jyväskylä. Publisher Copyright: © 2022 As humans, we seamlessly hold objects in our hands, and may even lose consciousness of these objects. This phenomenon raises the unsettled question of the involvement of the cerebral cortex, the core area for voluntary motor control, in dynamically maintaining steady muscle force. To address this issue, we measured magnetoencephalographic brain activity from healthy adults who maintained a steady pinch grip. Using a novel analysis approach, we uncovered fine-grained temporal modulations in the beta sensorimotor brain rhythm and its coupling with muscle activity, with respect to several aspects of muscle force (rate of increase/decrease or plateauing high/low). These modulations preceded changes in force features by ∼40 ms and possessed behavioral relevance, as less salient or absent modulation predicted a more stable force output. These findings have consequences for the existing theories regarding the functional role of cortico-muscular coupling, and suggest that steady muscle contractions are characterized by a stable rather than fluttering involvement of the sensorimotor cortex.

The effect of top-down attention on stimulus-evoked responses and alpha oscillations and the association between arousal and pupil diameter are well established. However, the relationship between these indices, and their contribution to the subjective experience of attention, remains largely unknown. Participants performed a sustained (10-30 s) attention task in which rare (10%) targets were detected within continuous tactile stimulation (16 Hz). Trials were followed by attention ratings on an 8-point visual scale. Attention ratings correlated negatively with contralateral somatosensory alpha power and positively with pupil diameter. The effect of pupil diameter on attention ratings extended into the following trial, reflecting a sustained aspect of attention related to vigilance. The effect of alpha power did not carry over to the next trial and furthermore mediated the association between pupil diameter and attention ratings. Variations in steady-state amplitude reflected stimulus processing under the influence of alpha oscillations but were only weakly related to subjective ratings of attention. Together, our results show that both alpha power and pupil diameter are reflected in the subjective experience of attention, albeit on different time spans, while continuous stimulus processing might not contribute to the experience of attention.

In this article, we present the clinical indications and advances in the use of magnetoencephalography to map the primary sensorimotor (SM1) cortex in neurosurgical patients noninvasively. We emphasize the advantages of magnetoencephalography over sensorimotor mapping using functional magnetic resonance imaging. Recommendations to the referring physicians and the clinical magnetoencephalographers to achieve appropriate sensorimotor cortex mapping using magnetoencephalography are proposed. We finally provide some practical advice for the use of corticomuscular coherence, cortico-kinematic coherence, and mu rhythm suppression in this indication. Magnetoencephalography should now be considered as a method of reference for presurgical functional mapping of the sensorimotor cortex.

Haptic devices can bring a sense of touch to virtual interactions, with substantial benefits for communication and health. Mid-air ultrasound can generate acoustic radiation forces for tailored tactile sensations - 'touch without touching'. To study the neuroscience of haptics, devices must be compatible with neural monitors. In this study, electromagnetic shielding with a Faraday was created. Our device creates a palpable focus of ultrasound with sufficient spatial resolution (5 mm diameter) and radiation pressure (1.56 or 1.76 Pa without or with Faraday cage lid, respectively) to stimulate small areas of skin. Magnetometer measurements showed minimal field strength variability around the system. Therefore, the proposed system could be compatible with neurological monitoring for neuroscience studies.

This chapter reviews the historical contribution of magnetoencephalography (MEG) to the understanding of the functioning of the somatosensory system and how some achievements have been transferred to clinical research or routine to be integrated in clinical guidelines. Considering the vast literature and the existence of comprehensive MEG review papers on the topic, the chapter focuses on pioneering or specific studies in a historical framework. Thanks to its noninvasiveness and excellent temporal and good spatial resolutions, MEG has substantially contributed in the past 50 years to the characterization of the spatial, temporal, and spectral dynamics of somatosensory system activity. It has brought a tremendous amount of novel insights into the neural mechanisms at the basis of body perception. The methods developed for this purpose appeared useful in clinical routine and also in clinical research to investigate the pathophysiology of various brain disorders.

How the human brain uses self-generated auditory information during speech production is rather unsettled. Current theories of language production consider a feedback monitoring system that monitors the auditory consequences of speech output and an internal monitoring system, which makes predictions about the auditory consequences of speech before its production. To gain novel insights into underlying neural processes, we investigated the coupling between neuromagnetic activity and the temporal envelope of the heard speech sounds (i.e. cortical tracking of speech) in a group of adults who 1) read a text aloud, 2) listened to a recording of their own speech (i.e. playback), and 3) listened to another speech recording. Reading aloud was here used as a particular form of speech production that shares various processes with natural speech. During reading aloud, the reader's brain tracked the slow temporal fluctuations of the speech output. Specifically, auditory cortices tracked phrases (, SCOPUS: ar.j, info:eu-repo/semantics/published

In multitalker backgrounds, the auditory cortex of adult humans tracks the attended speech stream rather than the global auditory scene. Still, it is unknown whether such preferential tracking also occurs in children whose speech-in-noise (SiN) abilities are typically lower compared with adults. We used magnetoencephalography (MEG) to investigate the frequency-specific cortical tracking of different elements of a cocktail party auditory scene in 20 children (age range, 6-9 years; 8 females) and 20 adults (age range, 21-40 years; 10 females). During MEG recordings, subjects attended to four different 5 min stories, mixed with different levels of multitalker background at four signal-to-noise ratios (SNRs; noiseless, +5, 0, and -5 dB). Coherence analysis quantified the coupling between the time courses of the MEG activity and attended speech stream, multitalker background, or global auditory scene, respectively. In adults, statistically significant coherence was observed between MEG signals originating from the auditory system and the attended stream at, info:eu-repo/semantics/published

Attention is subjectively experienced as a unified cognitive effort. This unitary experience of attention contrasts with the diversity of neural and peripheral correlates of attention. While the effects of attention on stimulus-evoked responses, alpha oscillations and pupil diameter, are well-known the relationship between these indices and the subjective experience of attention, has not yet been assessed. Participants performed a sustained (10 s to 30 s) attention task in which rare (10%) targets were detected within continuous tactile stimulation (16 Hz). Trials were followed by attention ratings on an 8-point Likert scale. Steady-state evoked fields (SSEFs) in response to tactile stimulation, as measured by magnetoencephalography, provided an objective measure of sensory processing. Beamformer source analysis of somatosensory alpha power was used as a measure of cortical excitability, while pupillometry provided a peripheral index of arousal. Attention ratings correlated negatively with contralateral somatosensory alpha power, and positively with pupil diameter. The effect of pupil diameter on attention ratings extended into the following trial, reflecting a sustained aspect of attention related to vigilance. The effect of alpha power did not carry over to the next trial, and furthermore mediated the effect of pupil diameter on attention ratings. Variation in SSEF power reflected stimulus processing under the influence of alpha oscillations, but were not readily expressed through subjective ratings of attention. Together, our results show that both alpha power and pupil diameter are reflected in the subjective experience of attention, albeit on different time spans, while continuous stimulus processing might not be metacognitively accessible.1Significance StatementAttention is subjectively experienced as a unified cognitive effort, in contrast with a diversity of neural and peripheral measures shown to correlate with attention. We present the first comprehensive study on the complex inter-relationship between the most common bio-physiological indices of attention, and their association with the subjective experience of attention. We show that the subjective experience of attention correlates negatively with cortical alpha oscillations, and positively with pupil diameter. The latter reflected a sustained aspect of attention, spanning several tens of seconds, related to vigilance. Alpha power, representing cortical control, fluctuated faster and mediated the effect of pupil diameter on attention. Tactile steady-state power reflected stimulus processing, also under the influence of alpha oscillations, but did not contribute much to subjective ratings of attention.

Corticokinematic coherence (CKC) is the phase coupling between limb kinematics and cortical neurophysiological signals, reflecting cortical processing of proprioceptive afference, and it is reproducible when estimated with magnetoencephalography (MEG). However, feasibility and reproducibility of CKC based on electroencephalography (EEG) is still unclear and is the primary object of the present report. Thirteen healthy right-handed volunteers (seven females, 21.7 ± 4.3 yr) participated in two combined MEG/EEG sessions 12.6 ± 1.3 mo apart. Participants' dominant and nondominant index finger was continuously moved at 3 Hz for 4 min separately using a pneumatic-movement actuator. Coherence was computed between finger acceleration and three derivations of EEG signals: 1) average reference, 2) bipolar derivations, and 3) surface Laplacian. CKC strength was defined as the peak coherence value at movement frequency. Intraclass-correlation coefficient values (0.74-0.93) indicated excellent intersession reproducibility for CKC strength for all derivations and moved fingers. CKC strength obtained with EEG was approximately two times lower compared with MEG, but the values were positively correlated across the participants. CKC strength was significantly (P < 0.01) higher for bipolar (session 1: 0.19 ± 0.09; session 2: 0.20 ± 0.10) and surface Laplacian (session 1: 0.22 ± 0.09; session 2: 0.21 ± 0.09) derivations than for the average reference (session 1: 0.10 ± 0.04; session 2: 0.11 ± 0.05). We demonstrated that CKC is a feasible and reproducible tool to monitor proprioception using EEG recordings, although the strength of CKC was twice lower for EEG compared with MEG. Laplacian and bipolar (CP3-C1/CP3-C3 and CP4-C2/C4-FC2) EEG derivation(s) are recommended for future research and clinical use of CKC method. NEW & NOTEWORTHY The most important message in this report is that the corticokinematic coherence (CKC) method is a feasible and reproducible tool to quantify, map, and follow cortical proprioceptive ("the movement sense") processing using EEG that is more widely available for CKC recordings than previously used magnetoencephalography designs, in basic research, but especially in clinical environments. We provide useful recommendations for optimal EEG derivations for cost-effective experimental designs, making it possible to scale up in sample size in future studies., info:eu-repo/semantics/published

In this article, we present the clinical indications and advances in the use of magnetoencephalography to map the primary sensorimotor (SM1) cortex in neurosurgical patients noninvasively. We emphasize the advantages of magnetoencephalography over sensorimotor mapping using functional magnetic resonance imaging. Recommendations to the referring physicians and the clinical magnetoencephalographers to achieve appropriate sensorimotor cortex mapping using magnetoencephalography are proposed. We finally provide some practical advice for the use of corticomuscular coherence, cortico-kinematic coherence, and mu rhythm suppression in this indication. Magnetoencephalography should now be considered as a method of reference for presurgical functional mapping of the sensorimotor cortex., SCOPUS: ar.j, info:eu-repo/semantics/published

SCOPUS: le.j, info:eu-repo/semantics/published

To gain novel insights into how the human brain processes self-produced auditory information during reading aloud, we investigated the coupling between neuromagnetic activity and the temporal envelope of the heard speech sounds (i.e., speech brain tracking) in a group of adults who 1) read a text aloud, 2) listened to a recording of their own speech (i.e., playback), and 3) listened to another speech recording. Coherence analyses revealed that, during reading aloud, the reader’s brain tracked the slow temporal fluctuations of the speech output. Specifically, auditory cortices tracked phrasal structure (HighlightsThe brain tracks phrasal and syllabic rhythmicity of self-produced (read) speech.Tracking of phrasal structures is attenuated during reading compared with listening.Speech rhythmicity mainly drives brain activity during reading and listening.Brain activity drives syllabic rhythmicity more during reading than listening.

To assess with magnetoencephalography the developmental vs progressive character of the impairment of spinocortical proprioceptive pathways in Friedreich ataxia (FRDA)., info:eu-repo/semantics/published