Loop-Closure of the Visual-Cortical Response
Abstract
Results of a study designed to test the effectiveness of using feedback to consciously connect humans to their evoked response and thereby 'close the loop' around the brain are presented. A technique to achieve loop closure using a lock-in amplifier approach is presented. Findings indicate that conscious control of EEG is possible. Each of the eight subjects tested was able to achieve control. Comparisons are made between loop-closure results and the human steady-state evoked potential (SSEP). The SSEP is obtained by recording and analyzing the visual evoked response to a sum-of-ten sine waves. This approach provides simultaneous multiple frequency measurements of the human EEG to the evoking stimulus in terms of describing functions (gain and phase) and remnant spectra. A relationship between the SSEP and loop-closure ability is discussed. Ways in which the SSEP quantities vary with the addition of a decision making task are also presented. Implications of these results in terms of secondary tasks for mental-state estimation and brain actuated control are addressed. Keywords: Visual evoked response, Frequency response anlaysis, Loop- closure, Biofeedback.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1988
- Accession Number
- ADA198348
Entities
People
- Craig W. Downey
- David F. Ingle
- John H. Schnurer
Organizations
- Armstrong Laboratory