Subject: Re: Cariani's question: "What is the visual analogue of pitch?" From: Eliot Handelman <eliot(at)GENERATION.NET> Date: Tue, 20 Jan 2004 18:32:41 -0500John Neuhoff wrote: >Stephen Handel once said that an analogy between vision and audition could >be "seductive, but misleading". In my opinion, Kubovy & Van Valkenburg's >"Pitch is to space as audition is to vision" idea has some serious >drawbacks. > I've been thinking recently about the relation of hearing to vision as it applies to the perception of music, eg the "construction" by the mind of a melody, such that when you listen there is a sense of a highly structured whole, or of a trend towards wholeness. In my work, which is about computational analysis of music, I've come to find that a useful approach is one that analogizes from computer vision -- ie, hierarchically builds up larger entities -- "objects" -- from low level features -- ie, things like orientational trends -- in a way that seems highly evocative of the patterns of computation that vision is known to imply. It's interesting to speculate that the procedures for listening to music might map rather gracefully from visual processes to hearing and perhaps even involve certain visual specializations. It would be useful to know, in this regard, whether we possess orientation-selective cells -- which doesn't seem implausible. If these existed, then almost certainly some sort of hierarchic computations would take advantage of these. I haven't seen any research that directly supports this, though. pitch::space = audition:vision strikes me as much too simple. If I'm right in thinking that music is a kind of auditory system analogue to vision, then there are very mny more factors that need to be accomodated. The most important of these, I think, are "parallelisms" -- ie, repetitions (in structure, for instance, and potentially at a very local level) that preserve a sense of "object constancy" -- eg the transposiion of a rhytmically-shaped interval or two. Even in very simple music -- like "happy birthday" -- these can be confoudedly complex for a program to work out. It gives an indication of the complexity of the brain the beast that regards this as a simple entertainment must posess. Ifr parallelism analysis corresponds to visual object constancy analysis, then surely the analogy would go something like this: relations-between-pitch::space = audition:vision. Just a few thoughts, but I'd be glad for any feedback. -- eliot ------- Eliot Handelman Ph.D Montreal, Canada > > > > > > >