Contrast

Download files
Access & Terms of Use
open access
Copyright: Pursell, Finn
Altmetric
Abstract
This thesis engages the contrast phenomenon in its various manifestations across the different sense modalities in order to assess the plausibility of contrast as a general perceptual principle. There is some question as to whether contrast may spill over into modalities it is not commonly associated with. In particular, a number of researchers have argued that contrast occurs in audition and has similarities to the brightness contrast illusion in visual perception. For example, studies of noise pitch have noted similar psychophysical properties to brightness contrast and invoked the same underlying neural mechanism. Furthermore, there is some suggestion that contrast may come in a non-simultaneous form characterised by perceptual exaggerations arising from the contrasting spectral content of successive auditory stimuli. The speech perception literature on context effects are engaged as it is in this domain that there is some evidence for non-simultaneous contrast. A study was conducted in which 34 subjects were presented synthesized tokens of "da" and "ga" diotically and dichotically following the precursors "al" and "ar". Significantly more "da" identifications were observed (F=62.85, p=.000) following "ar" precursors when stimuli were presented diotically, whereas no significant effects were observed in identifications of the target for different precursors (F=.553, p=.457) when targets were presented to the ear contralateral to that of the precursor. Results fail to support an explanation of the context effect in the form of a causal mechanism with a central locus. Rather, the locus of the context effect can only be hypothesized to occur at the periphery of the nervous system. This suggests that auditory contrast may be a plausible explanation for the context effect, and which if correct, may be a universal phenomenon common to all people regardless of environment and acquired knowledge. Given these results, contrast is explored more broadly. As generic use of the term is often encountered in musical contexts, aspects of music perception relating to contrast are examined. Some theoretical ideas are put forward in this capacity, focusing on an interactive neural network approach to understanding hypothetical structural contrasts, including tonal contrasts. The thesis closes with a consideration of contrast-like effects that may be of some relevance towards understanding contrast more generally.
Persistent link to this record
Link to Publisher Version
Link to Open Access Version
Additional Link
Author(s)
Pursell, Finn
Supervisor(s)
Walker, Robert
Schubert, Emery
Creator(s)
Editor(s)
Translator(s)
Curator(s)
Designer(s)
Arranger(s)
Composer(s)
Recordist(s)
Conference Proceedings Editor(s)
Other Contributor(s)
Corporate/Industry Contributor(s)
Publication Year
2010
Resource Type
Thesis
Degree Type
PhD Doctorate
Files
download whole.pdf 4.9 MB Adobe Portable Document Format
Related dataset(s)