EFFECTS OF STIMULUS CONTEXT IN HUMAN AUDITORY MEMORY
Abstract
Observers were required to perform a two-alternative forced choice (2AFC) high-low frequency discrimination task. Pitch memory was studied as a function of the temporal gap between the standard tone and the next input, the frequency range of the tones preceding and following the standard, the uncertainty regarding the length of the preceding sequence, and the noisiness of the standard and comparison tones. The results are discussed within the framework of an internal-noise model derived from the theory of signal detectability. A mechanism is suggested which can respond to frequency and serial position uncertainty by adopting different coding modes. In trace-coding mode, the trace is subject to temporal decay and retroactive interference: in context coding mode, the memory representation is independent of temporal effects. These results are contrasted with the predictions of extant stage models which incorporate automatic erasure mechanisms; such models are unable to satisfactorily account for the obtained data.
Degree
Ph.D.
Subject Area
Psychology|Experiments
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