Whether or not brain activation during motor imagery (MI), the mental rehearsal of movement, is modulated by experience (i.e. skilled performance, achieved through long‐term practice) remains ...unclear. Specifically, MI is generally associated with diffuse activation patterns that closely resemble novice physical performance, which may be attributable to a lack of experience with the task being imagined vs. being a distinguishing feature of MI. We sought to examine how experience modulates brain activity driven via MI, implementing a within‐ and between‐group design to manipulate experience across tasks as well as expertise of the participants. Two groups of ‘experts’ (basketball/volleyball athletes) and ‘novices’ (recreational controls) underwent magnetoencephalography (MEG) while performing MI of four multi‐articular tasks, selected to ensure that the degree of experience that participants had with each task varied. Source‐level analysis was applied to MEG data and linear mixed effects modelling was conducted to examine task‐related changes in activity. Within‐ and between‐group comparisons were completed post hoc and difference maps were plotted. Brain activation patterns observed during MI of tasks for which participants had a low degree of experience were more widespread and bilateral (i.e. within‐groups), with limited differences observed during MI of tasks for which participants had similar experience (i.e. between‐groups). Thus, we show that brain activity during MI is modulated by experience; specifically, that novice performance is associated with the additional recruitment of regions across both hemispheres. Future investigations of the neural correlates of MI should consider prior experience when selecting the task to be performed.
Experience modulates motor imagery‐based brain activity, inclusive of experience with the task being imagined and the expertise of the participant. Imagery of a novel task recruits more widespread brain areas vs. that for which the participant had a high degree of expertise (A). Imagery of tasks of for which participants had similar experience across groups resulted in limited differences (B). Results indicate that experience with the task being imagined should be considered when studying MI.
•Motor area development was investigated by age related changes of contingent negative variation (CNV) using high density EEG.•Age-related improvement of motor control efficiency.•Maturational ...increase in the contribution of the supplementary motor area (SMA) to movement preparation.•Prolonged motor area maturation into late adolescence.
The motor system undergoes significant development throughout childhood and adolescence. The contingent negative variation (CNV), a brain response reflecting preparation for upcoming actions, offers valuable insights into these changes. However, previous CNV studies of motor preparation have primarily focused on adults, leaving a gap in our understanding of how cortical activity related to motor planning and execution matures in children and adolescents.
The study addresses this gap by investigating the maturation of motor preparation, pre-activation, and post-processing in 46 healthy, right-handed children and adolescents aged 5-16 years. To overcome the resolution limitations of previous studies, we combined 64-electrode high-density Electroencephalography (EEG) and advanced analysis techniques, such as event-related potentials (ERPs), mu-rhythm desynchronization as well as source localization approaches. The combined analyses provided an in-depth understanding of cortical activity during motor control.
Our data showed that children exhibited prolonged reaction times, increased errors, and a distinct pattern of cortical activation compared to adolescents. The findings suggest that the supplementary motor area (SMA) plays a progressively stronger role in motor planning and response evaluation as children age. Additionally, we observe a decrease in sensory processing and post-movement activity with development, potentially reflecting increased efficiency. Interestingly, adolescent subjects, unlike young adults in previous studies, did not yet show contralateral activation of motor areas during the motor preparation phase (late CNV).
The progressive increase in SMA activation and distinct cortical activation patterns in younger participants suggest immature motor areas. These immature regions might be a primary cause underlying the age-related increase in motor action control efficiency. Additionally, the study demonstrates a prolonged maturation of cortical motor areas, extending well into early adulthood, challenging the assumption that motor control is fully developed by late adolescence. This research, extending fundamental knowledge of motor control development, offers valuable insights that lay the foundation for understanding and treating motor control difficulties.
The purpose of the current study was to explore the immediate effect of motor imagery (MI) involving finger movement of a given limb on cortical response and muscle activity in healthy subjects.
...Twenty healthy right-handed adults (7 females and 13 males) with a mean + SD age of 22.05 + 6.08 years participated in the study. The beta-band event-related desynchronization (ERD) at the sensorimotor cortex and muscle activity during finger movement tasks using either the index, middle, or thumb digits on the non-dominant left hand were compared before and after an MI training session. Subjects underwent a pre-MI, MI training, and finally a post-MI session where they either performed or imagined performing a button-pushing action 50 times per session with each of the three digits.
The ERD power in the beta frequency band was lower in pre-MI compared to post-MI and was significantly different between the pre- and post-MI sessions for both the index and middle fingers, but not the thumb. A significant decrease was seen in the mean muscle activity during post-MI compared to pre-MI for all the digits except the thumb.
The results from the current study suggest that complex MI can result in motor learning and improvement in motor performance, thereby requiring less effort during motion.
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•Study explored the immediate effect of motor imagery (MI) on cortical response and muscle activity.•Complex MI involving finger movements.•Comparable ERD patterns in pre-MI and post-MI, indicating significant ERD decreases.•Complex MI lead to motor learning and improved motor performance with reduced effort during motion.•Notable decrease in mean muscle activity during post-MI compared to pre-MI.
Neural mechanisms of human standing are expected to be elucidated for preventing fallings. Postural response evoked by sudden external perturbation originates from various areas in the central ...nervous system. Recent studies have revealed that the corticospinal pathway is one of the key nodes for an appropriate postural response. The corticospinal pathway that mediates the early part of the electromyographic response is modulated with prediction before a perturbation occurs. Temporal prediction explicitly exhibiting an onset timing contributes to enhancing corticospinal excitability. However, how the cortical activities in the sensorimotor area with temporal prediction are processed before the corticospinal pathway enhancement remains unclear. In this study, using electroencephalography, we investigated how temporal prediction affects both neural oscillations and synchronization between sensorimotor and distal areas. Our results revealed that desynchronization of cortical oscillation at α‐ and β‐bands was observed in the sensorimotor and parietooccipital areas (Cz, CPz, Pz and POz), and those are nested in the phase at θ‐band frequency. Furthermore, a reduction in the interareal phase synchrony in the α‐band was induced after the timing cue for the perturbation onset. The phase synchrony at the low frequency can relay the temporal prediction among the distant areas and initiate the modulation of the local cortical activities. Such modulations contribute to the preparation for sensory processing and motor execution that are necessary for optimal responses.
Cortical involvement is fundamental neural mechanism for a postural response. We revealed that EEG oscillations and interareal synchronization, at θ‐, α‐ and β‐band frequency, are dynamically modulated during the preparatory period when perturbation can be predicted.
Cerebrospinal and structural‐molecular neuroimaging in‐vivo biomarkers are recommended for diagnostic purposes in Alzheimer’s disease (AD) and other dementias; however, they do not explain the ...effects of AD neuropathology on neurophysiological mechanisms underpinning cognitive processes. Here, an Expert Panel from the Electrophysiology Professional Interest Area of the Alzheimer’s Association reviewed the field literature and reached consensus on the event‐related electroencephalographic oscillations (EROs) that show consistent abnormalities in patients with significant cognitive deficits due to Alzheimer’s, Parkinson’s (PD), Lewy body (LBD), and cerebrovascular diseases. Converging evidence from oddball paradigms showed that, as compared to cognitively unimpaired (CU) older adults, AD patients had lower amplitude in widespread delta (>4 Hz) and theta (4–7 Hz) phase‐locked EROs as a function of disease severity. Similar effects were also observed in PD, LBD, and/or cerebrovascular cognitive impairment patients. Non‐phase‐locked alpha (8–12 Hz) and beta (13–30 Hz) oscillations were abnormally reduced (event‐related desynchronization, ERD) in AD patients relative to CU. However, studies on patients with other dementias remain lacking. Delta and theta phase‐locked EROs during oddball tasks may be useful neurophysiological biomarkers of cognitive systems at work in heuristic and intervention clinical trials performed in AD patients, but more research is needed regarding their potential role for other dementias.
A multidisciplinary Expert Panel reviewed the literature and reached a consensus on the event‐related electroencephalographic oscillations (EROs) showing consistent abnormalities in patients with significant cognitive deficits due to Alzheimer’s, Parkinson’s (PD), Lewy body (LBD), and cerebrovascular diseases. Delta and theta phase‐locked EROs during oddball tasks may be useful as neurophysiological biomarkers of cognitive systems at work in AD patients, although those EEG measures were unspecific in relation to the other dementing disorders mentioned above.
We examined β‐ (∼20 Hz) and γ‐ (∼40 Hz) band activity in auditory cortices by means of magnetoencephalography (MEG) during passive listening to a regular musical beat with occasional omission of ...single tones. The β activity decreased after each tone, followed by an increase, thus forming a periodic modulation synchronized with the stimulus. The β decrease was absent after omissions. In contrast, γ‐band activity showed a peak after tone and omission, suggesting underlying endogenous anticipatory processes. We propose that auditory β and γ oscillations have different roles in musical beat encoding and auditory–motor interaction.
Losses usually have greater subjective value (SV) than gains of equal nominal value but often cause a relative deterioration in effortful performance. Since losses and gains induce differing ...approach/avoidance behavioral tendencies, we explored whether incentive type interacted with approach/avoidance motor‐sets. Alpha‐ and beta‐band event‐related desynchronization (ERD) was hypothesized to be weakest when participants expected a loss and prepared an inhibitory motor‐set, and strongest when participants expected a gain and prepared an active motor‐set. It was also hypothesized that effort would modulate reward and motor‐set–related cortical activation patterns. Participants completed a cued Go/NoGo task while expecting a reward (+10p), avoiding a loss (−10p), or receiving no incentive (0p); and while expecting a NoGo cue with a probability of either .75 or .25. Pre‐movement alpha‐ and beta‐band EEG power was analyzed using the ERD method, and the SV of effort was evaluated using a cognitive effort discounting task. Gains incentivized faster RTs and stronger preparatory alpha band ERD compared to loss and no incentive conditions, while inhibitory motor‐sets resulted in significantly weaker alpha‐band ERD. However, there was no interaction between incentive and motor‐sets. Participants were more willing to expend effort in losses compared to gain trials, although the SV of effort was not associated with ERD patterns or RTs. Results suggest that incentive and approach/avoidance motor tendencies modulate cortical activations prior to a speeded RT movement independently, and are not associated with the economic value of effort. The present results favor attentional explanations of the effect of incentive modality on effort.
This study investigates the effect of gains and losses on cognitive effort using pre‐movement event‐related desynchronization to measure attention and approach/avoidance motor tendencies. The results showed, for the first time, that approach/avoidance motor tendencies act independently of incentive modality, and that monetary gains contributed to improved effortful performance through increased attentional engagement.
Tau rhythms are largely defined by sound responsive alpha band (~8–13 Hz) oscillations generated largely within auditory areas of the superior temporal gyri. Studies of tau have mostly employed ...magnetoencephalography or intracranial recording because of tau's elusiveness in the electroencephalogram. Here, we demonstrate that independent component analysis (ICA) decomposition can be an effective way to identify tau sources and study tau source activities in EEG recordings. Subjects (N = 18) were passively exposed to complex acoustic stimuli while the EEG was recorded from 68 electrodes across the scalp. Subjects' data were split into 60 parallel processing pipelines entailing use of five levels of high‐pass filtering (passbands of 0.1, 0.5, 1, 2, and 4 Hz), three levels of low‐pass filtering (25, 50, and 100 Hz), and four different ICA algorithms (fastICA, infomax, adaptive mixture ICA AMICA, and multi‐model AMICA mAMICA). Tau‐related independent component (IC) processes were identified from this data as being localized near the superior temporal gyri with a spectral peak in the 8–13 Hz alpha band. These “tau ICs” showed alpha suppression during sound presentations that was not seen for other commonly observed IC clusters with spectral peaks in the alpha range (e.g., those associated with somatomotor mu, and parietal or occipital alpha). The choice of analysis parameters impacted the likelihood of obtaining tau ICs from an ICA decomposition. Lower cutoff frequencies for high‐pass filtering resulted in significantly fewer subjects showing a tau IC than more aggressive high‐pass filtering. Decomposition using the fastICA algorithm performed the poorest in this regard, while mAMICA performed best. The best combination of filters and ICA model choice was able to identify at least one tau IC in the data of ~94% of the sample. Altogether, the data reveal close similarities between tau EEG IC dynamics and tau dynamics observed in MEG and intracranial data. Use of relatively aggressive high‐pass filters and mAMICA decomposition should allow researchers to identify and characterize tau rhythms in a majority of their subjects. We believe adopting the ICA decomposition approach to EEG analysis can increase the rate and range of discoveries related to auditory responsive tau rhythms.
Auditory related alpha rhythms (i.e., tau rhythms) have historically been difficult to examine with the electroencephalogram (EEG). Here, we show that independent components analysis, combined with the right preprocessing routines, can be an effective way to examine tau rhythms in the EEG.
Motor impairments are common after stroke, but efficacious therapies for these dysfunctions are scarce. By extending an earlier study on the effects of music‐supported therapy, behavioral indices of ...motor function as well as electrophysiological measures were obtained before and after a series of therapy sessions to assess whether this new treatment leads to neural reorganization and motor recovery in patients after stroke. The study group comprised 32 stroke patients in a large rehabilitation hospital; they had moderately impaired motor function and no previous musical experience. Over a period of 3 weeks, these patients received 15 sessions of music‐supported therapy using a manualized step‐by‐step approach. For comparison 30 additional patients received standard rehabilitation procedures. Fine as well as gross motor skills were trained by using either a MIDI‐piano or electronic drum pads programmed to emit piano tones. Motor functions were assessed by an extensive test battery. In addition, we studied event‐related desynchronization/synchronization and coherences from all 62 patients performing self‐paced movements of the index finger (MIDI‐piano) and of the whole arm (drum pads). Results showed that music‐supported therapy yielded significant improvement in fine as well as gross motor skills with respect to speed, precision, and smoothness of movements. Neurophysiological data showed a more pronounced event‐related desynchronization before movement onset and a more pronounced coherence in the music‐supported therapy group in the post‐training assessment, whereas almost no differences were observed in the control group. Thus we see that music‐supported therapy leads to marked improvements of motor function after stroke and that these are accompanied by electrophysiological changes indicative of a better cortical connectivity and improved activation of the motor cortex.
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