Detecting Silent Vocalizations in a Locked-In Subject
Cross-correlations: data is from session 3 (day 1556, May 5, 2009) when loudness feedback (the speaker output volume increased in direct proportion to the firing frequency) was provided and synchronized single unit firing was optimal. Reference unit is Ch2_se_11 (top right panel). (a) The data segment shown in this figure was recorded 5 seconds after a local field potential spectral peak in the beta band. (b) This data segment was taken from a period of 5 seconds before the local field potential spectral peak in the lower beta band. (Lower beta band peak is @ 4346.55 seconds into file from day 1556.) Note the improved cross-correlations after the beta peak in panel (a). Data are selected from two channels, with 31 units in total.