'Peak preference' and waveform perception.

Because the perception of waveforms has been relatively neglected in vision research, one phenomenon of waveform perception, the parsing of waves into peak-shaped rather than trough-shaped segments, is examined. It is suggested that this so-called 'peak preference' is a grouping rule which can determine figure-background segregation in some circumstances. It appears to resist explanation in terms of the spatial-filtering properties of the visual system. For a complete explanation of peak preference, the ecological significance for actions that wave stimuli would normally have in the natural setting has to be considered.