The "Cyberlink" Brain-Body Interface as an Assistive Technology for Persons with Traumatic Brain Injury: Longitudinal Results from a Group of Case Studies

Abstract

A longitudinal study of traumatic brain-injured and comatose participants suggests that these individuals are able to learn to use a mental interface device to navigate a maze and perform some basic communication. The device, known as the "Cyberlink," uses electrooculargraphic, electromyographic, and electroencephlagraphic signals collected at the forehead to control cursor movement. Further details of the operation of the device and the set-up procedures are reported. Six adults, all of whom had traumatic brain injury or were believed to be comatose, participated in the study over a 7-month period. Initially, only one participant, who had previously used the device, could navigate the maze. At the end of the study all participants could navigate the maze, albeit with a high variability in success rate. Reasons for the variability obtained are postulated. The majority of participants could also use the device to type simple words. Positive behaviors and increases in attention span were also observed. The diagnosis of one participant was upgraded from coma to traumatic brain stem injury as a result of data collected during the study. Controls were built into the study in order to demonstrate intention. Further developments of the device and other applications where it may be useful are discussed. 249

Analysis of assets for virtual reality applications in neuropsychology

“…This strategy supported efficient use of training time. A more technically complex approach uses "biosignals", as seen in the use of the "Cyberlink" system (Doherty, Bloor, & Cockton, 1999). Initial results using this system suggested that persons with extreme motor and language impairments following stroke and traumatic brain injury were able to communicate using an EEG/EOG/EMG-driven cursor on a flatscreen computer.…”

The Emotiv EPOC neuroheadset: an inexpensive method of controlling assistive technologies using facial expressions and thoughts?

“…Like the Emotiv neuroheadset, the Brainfingers headband detects EMG, EOG and EEG activity. Doherty et al (1999Doherty et al ( , 2002 trialled the headband on six adults with brain injuries. Over a period of seven months, the participants learned to move a cursor left and right using eye movements, and up and down by controlling their EEG signals.…”

Gazing and frowning as a new human--computer interaction technique

“…A device called "Cyberlink" can be used to monitor eye movements with electrooculography (EOG), muscle activity with electromyography (EMG), and brain activity with electroencephalography (EEG) [Doherty et al 1999; see also Allanson et al 1999]. Barreto et al [2000] developed a method that combined the use of EOG (from cranial muscles) and EEG (from occipital lobe) signals for two-dimensional cursor movements by applying amplitude thresholds and power spectral density estimations.…”