It probably can’t have taken long after the first spectrum waterfall display was created, before somebody had a go at creating a waveform that would create an image in the waterfall. We don’t know who ...

The sleep EEG multitaper spectrogram reveals patterns of continuous changes in brain oscillation activity during sleep. Characteristic patterns clearly differentiate waking (left) from nonREM (center) ...

An example of a spectrogram, which scientists use to highlight sound sources based on their visual signatures. Credit must be given to the creator. Only noncommercial uses of the work are permitted.