Terhardt, E. (1987). Gestalt principles and music perception. In: Perception of Complex Auditory Stimuli (Yost, W.A., Watson, C.S., eds.), Erlbaum, Hillsdale, NJ, 157-166
Retracing the views of early Gestalt psychologists, a concept of Gestalt perception is suggested that is more stringent and coherent than approaches utilized to date. In particular, the contrast between "cognitive psychology" and "psychophysics" disappears in the concept, which is called Hierarchical Processing of Categories (HPC). Its main assumptions are: (1) that Gestalt perception is entirely depent on contourized and categorized sensory representations of external objects; and (2) that perception is organized in hierarchical layers in each of which basically one and the same type of processing goes on, i.e., categorization. With regard to auditory perception, it is pointed out that on the most peripheral level it is the spectral pitches which are analogous to primary visual contours, while virtual pitches are equivalent to "secondary", or "illusory" visual contours. Perception of musical tones, chords, and melodies is discussed in the light of the HPC concept.