http://www.arthurs-clipart.org/medical/senseorgans/cochlea%20diagram.gif
Lipscomb and Hodges provide a concise yet thorough overview of hearing and perception of sound and music. The chapter is organized by essentially tracing a soundwave from outside of the body, to inside the ear, to the brain and then to psychological attributes of sound.
The outer ear (pinna), middle ear (between the ear drum and cochlea; air-filled), and inner ear (semicircular canals and cochlea) are described. In particular, the cochlea is discussed fairly thoroughly; the vestibular canal, tympanic canal, helicotrema, round window, tectorial membrane, basiliar membrane (responsible in part for pitch recognition), outer and inner hair cells are described and their respective functions delineated.
The hair cells in the cochlea transfer mechanical energy of the waves in the cochlear fluid to electrochemical energy which then travels to the brain via the auditory nerve. Within the brain, multiple cites are responsible for the processing of the information received from the auditory nerve, and these are discussed.
The authors then proceed to correlate physical and perceptual (psychological) variables of sound according to the theories set forth by Carl Seashore. Seashore adds a third variable to the physical and perceptual levels: what he called “trunklines of musicality.” The correspondences are as follows (physical/perceptual/trunkline): frequency/pitch/tonal, amplitude/loudness/dynamic, signal shape/timbre/qualitative, and time/duration/temporal. Each of these points is the discussed, after an explanation of the critical band.
Consonance, dissonance, simultaneous tones, hearing loss, masking, overtones/harmonics, and psychological constructs of the “present” in terms of time are all explained in this chapter as well, though the required brevity of this summary does not permit a further exploration of these here.
Finally, the authors discuss anomalies in Seashore’s model, noting research indicating that the relationship between the acoustical and psychoacoustical phenomena delineated by Seashore are not entirely accurate (though they still provide a good functional model).
Personally, if I had to choose one chapter to summarize hearing and perception, this would be it. The writing is clear and the required content is covered without too much superfluous material or too elementary of a treatment.
I strongly recommend that this chapter appear as one of the first readings for this class as it provides the necessary groundwork for the progression from ‘simple’ hearing to actual audiation. I found it particularly interesting that research has begun to support the concept that ‘learning can cause modifications in sensory processing’ (p.93). We (you and I, Todd) seem to be throwing in the ‘nature versus nurture’ concept sporadically. This is certainly another finding that supports nurture.
ReplyDeleteSeashore discusses the trunklines of musicality almost immediately in his first chapter of ‘Psychology of Music’, a welcome addition to Hodges’s chapter. But I have to sincerely say that the between the headings ‘perception of pitch’ and ‘perception of loudness’ I was lost in a sea of jargon. Hopefully we can clear some things up in our skype call today.