This study examines the feasibility of using electroencephalograms (EEGs) to rapidly detect the intent to open one’s hand in individuals with complete hand paralysis following a subcortical ischemic stroke. If detectable, this motor planning activity could be used in real time to trigger a motorized hand exoskeleton or an electrical stimulation device that opens/closes the hand. While EEG-triggered movement-assist devices could restore function, they may also promote recovery by reinfor-cing the use of remaining cortical circuits. EEGs were recorded while participants were cued to either relax or attempt to extend their fingers. Linear discriminant analysis was used to detect onset of finger extension from the EEGs in a leave-onetrial-out cross-validation process. In each testing trial, the classifier was applied in pseudo real time starting from an initial hand-relaxed phase, through movement planning, and into the initial attempted finger extension phase (finger extension phase estimated from typical time-to-movement-onset measured in the unaffected hand). The classifiers detected attempted finger-extension at a significantly higher rate during both motor planning and early attempted execution compared to rest.

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In order to realize haptic interaction (e.g., holding, pushing, and contacting the object) in virtual environment and mediated haptic communication with human beings (e.g., handshaking), the force feedback is required. Recently there has been a substantial need and interest in haptic displays, which can provide realistic and high fidelity physical interaction in virtual environment. The aim of our research is to implement wearable haptic displays for presentation of realistic feedback (kinesthetic stimulus) to the human arm. We developed wearable devices FlexTorque and FlexTensor that induce forces to the human arm and do not require holding any additional haptic interfaces in the human hand. It is a new technology for Virtual Reality that allows user to explore surroundings freely. The concept of Karate (empty hand) Haptics proposed by us is opposite to conventional interfaces (e.g., Wii Remote, SensAble’s PHANTOM, SPIDAR [1]) that require holding haptic interface in the hand, restricting thus the motion of the fingers in midair. The HapticEye interface allows the blind person to explore the unknown environment in a natural and effective manner. The wearer can literally see the environment by hand.

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