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Motor-Imagery based BCI (MI-BCI) neurorehabilitation can improve locomotor ability and reduce the deficit symptoms in Parkinson's Disease patients. Advanced Motor-Imagery BCI methods are needed to overcome the accuracy and time-related MI BCI calibration challenges in such patients. In this study, we proposed a Multi-session FBCSP (msFBCSP) based on inter-session transfer learning and we investigated its performance compared to the single-session based FBSCP. The main result of this study is the significantly improved accuracy obtained by proposed msFBCSP compared to single-session FBCSP in PD patients (median 81.3%, range 41.2-100.0% vs median 61.1%, range 25.0-100.0%, respectively; p

Over the years motor deficit in Parkinson's Disease (PD) patients was largely studied, however, no consistent pattern of relations between quantitative electroencephalography (qEEG) and motor scales emerged. There is a general lack of information on the relation between EEG changes and scales related to specific motor deficits. Therefore, the study aimed to investigate the relation between brain oscillatory activity alterations (EEG power bands) and most used PD-related motor deficit scales. A positive correlation was found between the freezing of the gait questionnaire (FOGQ) and delta spectral power band (rho=0.67; p=0.008), while a negative correlation with the same scale was observed in the alpha spectral power band (rho=-0.59, p=0.027). Additionally, motor scores measure by motor part of Unified Parkinson's Disease Rating Scale (UPDRS) correlated directly with theta (rho=0.55, p=0.040) and inversely with beta EEG power band (rho=-0.77, p=0.001). No significant correlation was found between spectral powers and Hoehn and Yahr (H&Y), BERG (Berg K. et. al. 1995), Modified Parkinson Activity Scale (MPAS), Six-Minute Walk Test (6MWT) and Timed Up and Go Test (TUG). In conclusion, our study supports the earlier findings suggesting a link between EEG slowing and motor decline, providing more insight into the relation between EEG alteration and deficits in different motor domains. These findings indicate that EEG assessment may be a useful biomarker for objective monitoring of progression and neurophysiological effect of rehabilitation approaches in PD's.

The human central nervous system integrates different sensory modalities with the visual information to produce a coherent mental representation of our own body, making us capable not only to process sensory events but also to plan and executes movements in the surrounding space. The basis of Mirror Therapy (MT) is the use of a mirror to create a visual reflection of an affected limb to create an illusion of movement of the paretic part of the limb. One of the uses of the MT is in motor recovery in post-stroke hemiparesis and even thought that it is valuable rehabilitation tool, its underlying neurophysiological manifestations and interaction with Motor Imagery (MI) are still unknown. Our study aim is to assess the effect of the MT by applying Forearm Bisection Test (FBT) and EEG measurement of the Event-related (de)synchronisation (ERD/S). Our results show that FBT scores were significantly higher in experimental Mirror Box (MB) group compared to control (CN) group (median 13.54 vs 0.00, respectively; p = 0.003). Furthermore, ΔERD/S (post-pre) differed significantly between the hemispheres in the MB group in the Mu, betalow and betahigh EEG bands, whilst did not differ in the CN group in the Mu and betalow bands. The results demonstrate improvement in ERD/S MI and an update of the body representation caused by MT. Moreover, findings suggest that the reflection of the moving hand in the mirror created an illusion of concomitant movement in the opposite hand that modulate the arm length representation which is detectable even during MI at EEG level. Our findings of neural basis and link of the MT and MI supports MT as favourable neurorehabilitation tool for motor recovery affecting not only the areas governing the moving hand but also the corresponding regions of the other hemisphere.

The study reports the performance of Parkinson's disease (PD) patients to operate Motor-Imagery based Brain-Computer Interface (MI-BCI) and compares three selected pre-processing and classification approaches. The experiment was conducted on 7 PD patients who performed a total of 14 MI-BCI sessions targeting lower extremities. EEG was recorded during the initial calibration phase of each session, and the specific BCI models were produced by using Spectrally weighted Common Spatial Patterns (SpecCSP), Source Power Comodulation (SPoC) and Filter-Bank Common Spatial Patterns (FBCSP) methods. The results showed that FBCSP outperformed SPoC in terms of accuracy, and both SPoC and SpecCSP in terms of the false-positive ratio. The study also demonstrates that PD patients were capable of operating MI-BCI, although with lower accuracy.

In the present study, 30 right-handed participants randomly performed one of three motor neurorehabilitation paradigms: action observation (AO), motor imagery (MI) and combined action observation and motor imagery (AO+MI) of the right arm and hand movement. Resting state electroencephalography (EEG) was acquired for 5 min before and immediately after the motor paradigms session. EEG was recorded from 10 sites over sensorimotor areas, and the average power was calculated for left (FC3, C3, C1, C5, CP3) and right (FC4, C4, C2, C6, CP4) regions in the spectral bands: delta, theta, alpha, mu, low and high beta. Our main finding demonstrates that delta, theta and mu activity decreased significantly on the contralateral regions during MI, while low beta increased significantly. Except for the mu band, the same changes were observed on the ipsilateral side, where delta and theta decreased significantly, while low beta became significantly higher. No relevant effects were observed for AO or combined AO and MI. These findings demonstrate a rapid effect of MI on cortical modulation in sensorimotor areas which is revealed by changes in resting state oscillatory activity and suggest an interesting interplay between MI and AO. The presented findings may be relevant for choosing a proper protocol for clinical motor neurorehabilitation approaches.

In this study, we examined the effect of neurofeedback on EEG changes due to immobilization of the dominant hand. Desynchronization of the sensorimotor rhythms during motor imagery was used as a tool to investigate brain activity. The study is based on 8 healthy subjects who underwent immobilization of the dominant hand for 24 hours. The electrical activity of the sensorimotor region of the cerebral cortex was registered during mental imagery of hand movements before the immobilization, soon after its removal and after a single session of neurofeedback. The control of the feedback stimuli was based on changes in sensorimotor rhythms produced by imagination of movement. Preliminary results show that immobilization caused changes in alpha and beta rhythms that were rapidly reversed after a single session of neurofeedback. At the end of the full study, if the here presented observations will still hold, the neurofeedback protocol will be proposed for routine rehabilitation sessions in patients suffering partial or total limb disability.

a b s t r a c t Humans perceive continuous speech through interruptions or brief noise bursts cancelling entire phonemes. This robust phenomenon has been classically associated with mechanisms of perceptual restoration. In parallel, recent experimental evidence suggests that the motor system may actively par- ticipate in speech perception, even contributing to phoneme discrimination. In the present study we intended to verify if the motor system has a specific role in speech perceptual restoration as well. To this aim we recorded tongue corticospinal excitability during phoneme expectation induced by contextual information. Results showed that phoneme expectation determines an involvement of the individual's motor system specifically implicated in the production of the attended phoneme, exactly as it happens during actual listening of that phoneme, suggesting the presence of a speech imagery-like process. Very interestingly, this motoric phoneme expectation is also modulated by subtle coarticulation cues of which the listener is not consciously aware. Present data indicate that the rehearsal of a specific phoneme requires the contribution of the motor system exactly as it happens during the rehearsal of actions exe- cuted by the limbs, and that this process is abolished when an incongruent phonemic cue is presented, as similarly occurs during observation of anomalous hand actions. We propose that altogether these effects indicate that during speech listening an attentional-like mechanism driven by the motor system, based on a feed-forward anticipatory mechanism constantly verifying incoming information, is working allowing perceptual restoration. © 2011 Elsevier Ltd. All rights reserved.

The present study investigates a Brain-Computer Interface (BCI) spelling procedure based on the P300 evoked potential. It uses a small matrix of words arranged in a tree-shaped organization (“multimenu”), and allows the user to build phrases one word at a time, instead of letter by letter. Experiments were performed in two sessions on a group of seven healthy volunteers. In the former, the “multimenu” was tested with a total of 60 choices: 30 “externally-imposed” selections and 30 “free-choice” selections. In the latter, 3 × 3 matrices were compared with 6 × 6 matrices. Each matrix was composed of letters or words, for a total of four matrices. Differences in classifier accuracy, bit rate and amplitude of the evoked P300 were evaluated. Average accuracy in all subjects was 87% with no differences between the selection methods. The 3 × 3 “multimenu” obtained the same level of classifier accuracy as the 6 × 6 matrices, even with a significantly lower amplitude of the P300. Bit rate was increased when using the 3 × 3 matrices compared to the 6 × 6 ones. The “multimenu” system was equally effective, but faster than conventional, letter-based matrices. By improving the speed of communication, this method can be of help to patients with severe difficulties in communication.

The premotor cortex is one of the fundamental structures composing the neural networks of the human brain. It is implicated in many behaviors and cognitive tasks, ranging from movement to attention and eye-related activity. Therefore, neural circuits that are related to premotor cortex have been studied to clarify their connectivity and/or role in different tasks. In the present work, we aimed to investigate the propagation of the neural activity evoked in the dorsal premotor cortex using transcranial magnetic stimulation/electroencephalography (TMS/EEG). Towards this end, interest was focused on the neural dynamics elicited in long-ranging temporal and spatial networks. Twelve healthy volunteers underwent a single-pulse TMS protocol in a resting condition with eyes closed, and the evoked activity, measured by EEG, was compared to a sham condition in a time window ranging from 45 msec to about 200 msec after TMS. Spatial and temporal investigations were carried out with sLORETA. TMS was found to induce propagation of neural activity mainly in the contralateral sensorimotor and frontal cortices, at about 130 msec after delivery of the stimulus. Different types of analyses showed propagated activity also in posterior, mainly visual, regions, in a time window between 70 and 130 msec. Finally, a likely “rebounding” activation of the sensorimotor and frontal regions, was observed in various time ranges. Taken together, the present findings further characterize the neural circuits that are driven by dorsal premotor cortex activation in healthy humans.

Involvement of the ipsilateral hemisphere during planning of reaching movements is still matter of debate. While it has been demonstrated that the contralateral hemisphere is dominant in visuo-motor integration, involvement of the ipsilateral hemisphere has also been proposed. Furthermore, a dominant role for left posterior parietal cortex has been shown in this process, independently of the hand and visual field involved. In this study, the possible involvement of ipsilateral parieto-occipital cortex in planning of reaching movements was investigated by transcranial magnetic stimulation (TMS). TMS was applied on four points of the parietal and occipital cortex at 50% (Time 1), 75% (Time 2) and 90% (Time 3) of reaction time from a go-signal to hand movement. The only effect observed was an increase in reaction time when a region around the parieto-occipital junction was stimulated at Time 2. These results provide further support to the hypothesis that, in the posterior parietal cortex, planning of reaching movements also relies on the ipsilateral hemisphere, in addition to the contralateral or dominant one.