Brain-computer interfacing and neurofeedback  

Neuper C.
Department of Psychology, Section of Neuropsychology, University of Graz, Graz, Austria

Brain-computer interfaces (BCI) connect the living human brain with an external system. Motivated by the idea of controlling machines not by manual operation, but by "mere thinking", researchers working at the crossroads of neurosciences, computer science, biomedical engineering and psychology have joined forces and started to develop first prototypes of BCIs over the last decade. Common goals are, for example, to develop novel communication devices, neural prostheses, and therapeutic tools to assist people with severe motor disabilities. Such a BCI system uses a person's brain activity, i.e. specific features automatically extracted from the recorded brain signals, to operate computer controlled devices. Herewith, the system translates particular intentions into actions – such as moving a wheelchair, selecting a letter from a virtual keyboard, or grasping with the aid of a neuroprostesis. The neuronal activity of the brain can be recorded non-invasively with electroencephalography, magnetoencephalography, and imaging technology as well as invasively with electrocorticography or intracortical recordings. Within a closed loop, users are provided with visual, auditory, or tactile feedback of a specific component of their brain activity which enables them, to some extent, to regulate this activity. In many studies it has been shown that patients with severe motor impairment can learn to communicate and control devices by means of a BCI. Moreover, newly developed BCIs offer promise for clinical therapy and rehabilitation to improve motor and cognitive function and to influence emotional reaction. There are still some technical problems to overcome to broaden the field of BCI application, but especially the influence of psychological variables on BCI performance remains to be elucidated in further research.