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Keeping patients from being distracted while performing motor rehabilitation is important. An EEG-based biofeedback strategy has been introduced to help encourage participants to focus their attention on rehabilitation tasks. Here, we suggest a BCI-based monitoring method using a flickering cursor and target that can evoke a steady-state visually evoked potential (SSVEP) using the fact that the SSVEP is modulated by a patient’s attention. Fifteen healthy individuals performed a tracking task where the target and cursor flickered. There were two tracking sessions, one with and one without flickering stimuli, and each session had four conditions in which each had no distractor (non-D), a visual (vis-D) or cognitive distractor (cog-D), and both distractors (both-D). An EEGNet was trained as a classifier using only non-D and both-D conditions to classify whether it was distracted and validated with a leave-one-subject-out scheme. The results reveal that the proposed classifier demonstrates superior performance when using data from the task with the flickering stimuli compared to the case without the flickering stimuli. Furthermore, the observed classification likelihood was between those corresponding to the non-D and both-D when using the trained EEGNet. This suggests that the classifier trained for the two conditions could also be used to measure the level of distraction by windowing and averaging the outcomes. Therefore, the proposed method is advantageous because it can reveal a robust and continuous level of patient distraction. This facilitates its successful application to the rehabilitation systems that use computerized technology, such as virtual reality to encourage patient engagement. [ABSTRACT FROM AUTHOR]

Action observation training based on the theory of activation of the mirror-neuron system has been used for the rehabilitation of patients with stroke. In this paper, we sought to assess whether a brain–computer interface (BCI)-based action observation rehabilitation game, using a flickering action video, could preferentially activate the mirror-neuron system. Feedback of stimulus observation, evoked by the flickering action video, was provided using steady state visually evoked potential and event-related desynchronization. Fifteen healthy subjects have experienced the game with BCI interaction (game and interaction), without BCI interaction (game without interaction), observed non-flickering stimuli, and flickering stimuli without the game background (stimuli only) in a counter-balanced order. The game and interface condition was resulted in significantly stronger activation of the mirror-neuron system than did the other three conditions. In addition, the amount of mirror-neuron system activation is gradually decreased in the game without interface, non-flickering stimuli, and stimuli only conditions in a time-dependent manner; however, in the game and interface condition, the amount of mirror-neuron system activation was maintained until the end of the training. Taken together, these data suggest that the proposed game paradigm, which integrates the action observation paradigm with BCI technology, could provide interactive responses for whether watching video clips can engage patients and enhance rehabilitation. [ABSTRACT FROM AUTHOR]

Goal: Micromagnetic stimulation using coils sufficiently small to be implanted has been suggested as a potential method to overcome the limitations of electrical stimulation. We investigated the temperature increases in the brain implanted with planar coils. Methods: We conducted computational simulations on the thermal effects of implantable magnetic stimulation in a brain model using finite-element analysis, by varying geometric parameters of planar spiral coils, and repetitive stimulation pulse patterns. Results: It was revealed that the temperature increase in the brain can be controlled by a careful design of coils to implant. The coil diameter greater than 8 mm was required to induce a temperature rise in the brain of less than 1 °C. If the coil diameter was larger than 10 mm, the subsequent temperature rises in the brain tissue was maintained consistently at about 0.24 °C or lower. Conclusion: Selection of the number of coil turns must rely on tradeoffs between the required current and voltage that the implanted source can generate, as the required voltage increases while the required current decreases with increasing number of coil turns. Additionally, the coil insulation with a thickness of a few micrometers was found to suppress the temperature rise in the brain effectively. Significance: Although these simulations employed only one threshold value of 10 V/m, which is rather on the lower end of stimulation threshold, the simulation results are expected to serve as guidelines for designing planar coils to be implanted in the brain for magnetic stimulation. [ABSTRACT FROM PUBLISHER]