A SYSTEM FOR ALIGNING VIDEO-RECORDED VISUAL DATA AND HIGH-QUALITY MULTICHANNEL RECORDINGS OF SIMULTANEOUSLY OCCURRING SIGNALS

An electronic circuit is described which provides a unique number for each video frame, and which is superimposed on the frame as a 4-digit light-emitting diode display using a second camera and videomixer. The number is also encoded as a simple voltage waveform which is recorded separately together with electrical signals giving information about events related to; and coincident with, the visual data, for example n erve spike trains. Sophisticated computer analysis of signals can thus be related accurately to microscopical visual information processed b y video analysis.