Mechanisms of auditory backward masking in the stimulus suffix effect.

Abstract

Four hypotheses are given for backward masking by a stimulus suffix of auditory information about the end of an immediate memory list. Masking by erasure (displacement), integration (overwriting), and attentional interruption (diversion of a readout process) was rejected by evidence that (a) multiple suffixes produce a smaller masking effect than single suffixes; (b) a suffix that occurs simultaneously with the last memory item on the list has a smaller effect than one that is delayed by a few hundred milliseconds; and (c) the size of the suffix effect depends on its delay, independent of the rate at which the list was presented. These pieces of evidence are consistent with a masking model based on the operation of lateral inhibition among memory representations of auditory sensory events that are classified by time of arrival and by sensory channel characteristics. A functional model for the suffix effect was constructed from three factors believed to depend on the delay between a memory list and a suffix: (a) integration at short list-suffix delays, (b) backward masking through lateral inhibition at longer delays, and (c) readout of target stimulus information at delays of as long as a second or more.

The TRACE model of speech perception

“…Several of these aspects of TRACE overlap with assumptions made in other models, as mentioned in previous sections; continuity between working memory and the perceptual processing structures has been suggested by a number of other authors (e.g., Conrad, 1962), and the notion that working memory is a dynamic processing structure rather than a passive data structure has previously been advocated by (Crowder, 1978(Crowder, , 1981 and Grossberg (1978).…”

“…Both feedback models and dual code models can accommodate the fact that vowels show less of a tendency toward categorical perception than consonants (Fry, Abramson, Eimas, and Liberman, 1962;Pisoni, 1973). It is simply necessary to assume that vowel features are more persistent than consonant features (Crowder, 1978(Crowder, , 1981Fujisaki and Kawashima, 1968;Pisoni, 1973Pisoni, , 1975. However, the two classes of interpretations do differ in one way.…”

“…The architecture of TRACE bears a strong resemblance to the 'neural spectrogram' proposed by Crowder (1978; to account for interference effects between successive items in short-term memory. Like our Trace, Crowder's neural spectrogram provides a dynamic working memory representation of a spoken input.…”

“…It used to be common to view these influences as resulting from fatigue of feature detectors, as suggested initially by Eimas and Corbit. However, these effects might also be attributed to other processes, such as judgement and decision mechanisms (Diehl, Elman, & McCusker, 1978;Elman, 1979), or lateral inhibitory interactions in the 'neural spectrogram ' of Crowder (1978' of Crowder ( , 1981. Recent evidence suggests that adaptation effects may be occurring at several different levels, with different mechanisms contributing to the effects at different levels (see Sawusch, in press, for a discussion).…”

Two-component theory of the suffix effect: Contrary evidence

“…The suffix effect has received numerous theoretical treatments (for recent reviews, see Neath & Surprenant, 2003), but the historically most influential is the first-namely, the theory of precategorical acoustic storage, or PAS (Crowder, 1978;Crowder & Morton, 1969; see also Greene & Crowder, 1984b;Morton, Marcus, & Ottley, 1981). This is an informationprocessing theory, with PAS conceived of as a peripheral structure that retains speech-related information in a relatively raw (precategorical) form for at least 2 sec.…”