Detection of pulse signals in noise: trace-to-trace correlation in visual displays

Available experimental data (some previously published, some new) are reviewed, and some theoretical considerations discussed, with a view to establishing the nature of the phenomena whereby side-by-side presentation of traces, or serial presentation of p.p.i. pictures at intervals great enough to eliminate electrical or visual integration, gives much superior detection to that obtained by true integration. Although no complete explanation has been achieved, nevertheless a number of definite conclusions are arrived at.