Abstract: Objective:Recent research by the authors has investigated alpha wave amplitude increases in response to reduced visual input as a system for controlling electrical devices, with application for the disabled. However, alpha wave changes contingent with visual input is poorly understood. Further research was conducted on this phenomenon in order to optimize our ability to harness it as a control device. Study Design:To address this lack, alpha wave reactivity was studied in 21 non-disabled and 16 neurologically disabled (spinal cord injured; SCI) persons in laboratory conditions. Results:Large increases in alpha wave reactivity occurred in the 8–12 Hz range in posterior, central and anterior regions of the brain for both groups. There were no significant differences between the two groups in terms of alpha wave increases in amplitude following eye closure (EC) in the posterior cortex. Not all subjects showed similar increases in all cortical areas. No significant differences in alpha wave amplitude increases following EC were found for sex, age, handedness or hemisphere. However, in the non disabled group, substantial negative associations occurred of body mass index with all cortical sites, while mild but consistent positive associations were found for diastolic blood pressure. Conclusion:SCI persons have sufficient amounts of alpha wave reactivity contingent with eye closure to operate a hands free control device. The information from this research will be used to optimize technology being designed to activate, quickly and remotely, electrical devices using brain signals.
