Effects of the build-up and resetting of auditory stream segregation on temporal discrimination.

[Correction Notice: An erratum for this article was reported in Vol 34(6) of Journal of Experimental Psychology: Human Perception and Performance (see record 2008-16831-007). The year listed is incorrect. The article should have been dated 2008.] The tendency to hear a tone sequence as 2 or more streams (segregated) builds up, but a sudden change in properties can reset the percept to 1 stream (integrated). This effect has not hitherto been explored using an objective measure of streaming. Stimuli comprised a 2.0-s fixed-frequency inducer followed by a 0.6-s test sequence of alternating pure tones (3 low [L]-high [H] cycles). Listeners compared intervals for which the test sequence was either isochronous or the H tones were slightly delayed. Resetting of segregation should make identifying the anisochronous interval easier. The HL frequency separation was varied (0-12 semitones), and properties of the inducer and test sequence were set to the same or different values. Inducer properties manipulated were frequency, number of onsets (several short bursts vs. one continuous tone), tone:silence ratio (short vs. extended bursts), level, and lateralization. All differences between the inducer and the L tones reduced temporal discrimination thresholds toward those for the no-inducer case, including properties shown previously not to affect segregation greatly. Overall, it is concluded that abrupt changes in a sequence cause resetting and improve subsequent temporal discrimination. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Correction to Roberts et al. (2008).

Reports an error in "Effects of the build-up and resetting of auditory stream segregation on temporal discrimination" by Brian Roberts, Brian R. Glasberg and Brian C. J. Moore (Journal of Experimental Psychology: Human Perception and Performance, 2008[Aug], Vol 34[4], 992-1006). The year listed is incorrect. The article should have been dated 2008. (The following abstract of the original article appeared in record 2008-09670-016.) The tendency to hear a tone sequence as 2 or more streams (segregated) builds up, but a sudden change in properties can reset the percept to 1 stream (integrated). This effect has not hitherto been explored using an objective measure of streaming. Stimuli comprised a 2.0-s fixed-frequency inducer followed by a 0.6-s test sequence of alternating pure tones (3 low [L]-high [H] cycles). Listeners compared intervals for which the test sequence was either isochronous or the H tones were slightly delayed. Resetting of segregation should make identifying the anisochronous interval easier. The HL frequency separation was varied (0-12 semitones), and properties of the inducer and test sequence were set to the same or different values. Inducer properties manipulated were frequency, number of onsets (several short bursts vs. one continuous tone), tone:silence ratio (short vs. extended bursts), level, and lateralization. All differences between the inducer and the L tones reduced temporal discrimination thresholds toward those for the no-inducer case, including properties shown previously not to affect segregation greatly. Overall, it is concluded that abrupt changes in a sequence cause resetting and improve subsequent temporal discrimination. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Auditory perception of position and speed.

2 experiments were carried out to test the ability of train drivers to use sounds for the recognition of position and speed. The procedure involved playing tape recordings of 2 steam locomotives leaving known points and traveling at known speeds to experienced train drivers in a laboratory situation. Results show that Ss were able to recognize the position recordings better than predicted by chance, and that they were able to rank the speed recordings relative to each other, but they were not able to assign accurate values to the latter in terms of miles per hour. There were no significant differences in respect of the 2 locomotives. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Toward a neurophysiological theory of auditory stream segregation.

Auditory stream segregation (or streaming) is a phenomenon in which 2 or more repeating sounds differing in at least 1 acoustic attribute are perceived as 2 or more separate sound sources (i.e., streams). This article selectively reviews psychophysical and computational studies of streaming and comprehensively reviews more recent neurophysiological studies that have provided important insights into the mechanisms of streaming. On the basis of these studies, segregation of sounds is likely to occur beginning in the auditory periphery and continuing at least to primary auditory cortex for simple cues such as pure-tone frequency but at stages as high as secondary auditory cortex for more complex cues such as periodicity pitch. Attention-dependent and perception-dependent processes are likely to take place in primary or secondary auditory cortex and may also involve higher level areas outside of auditory cortex. Topographic maps of acoustic attributes, stimulus-specific suppression, and competition between representations are among the neurophysiological mechanisms that likely contribute to streaming. A framework for future research is proposed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Auditory Scene Analysis and the Role of Phenomenology in Experimental Psychology.

This paper is about two topics: a) the role of subjectivity in psychological research; and, b) my research on the perceptual organization of sound, in which subjectivity has played an important role. Audio demonstrations that appeal to the subjective experience of the reader are presented in lieu of objective research data to support the claims made about auditory organization. It is argued that all psychological research depends on an underlying framework of intuition (unformalized knowledge acquired through everyday experience), and that this intuition plays a role in the design of the experiment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Meaning dimensions and male-female voice perception in schizophrenics with good and poor premorbid adjustment.

This study explored certain aspects of perceptual distortion in schizophrenia. Among schizophrenics with a good premorbid adjustment, schizophrenics with a poor premorbid adjustment, and normals, auditory perception of spoken material was compared as a function of (a) sex of voice and (b) dimensions of meaning. The Ss listened to successive presentations of a recorded spoken word, mixed with decreasing amounts of masking noise, until their recognition threshold were established. Schizophrenics with poor premorbid adjustment responding to the female voice had significantly higher thresholds than those responding to the male voice. This finding did not occur in schizophrenics with good premorbid adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of context on auditory stream segregation.

The authors examined the effect of preceding context on auditory stream segregation. Low tones (A), high tones (B), and silences (-) were presented in an ABA- pattern. Participants indicated whether they perceived 1 or 2 streams of tones. The A tone frequency was fixed, and the B tone was the same as the A tone or had 1 of 3 higher frequencies. Perception of 2 streams in the current trial increased with greater frequency separation between the A and B tones (Δf). Larger Δf in previous trials modified this pattern, causing less streaming in the current trial. This occurred even when listeners were asked to bias their perception toward hearing 1 stream or 2 streams. The effect of previous Δf was not due to response bias because simply perceiving 2 streams in the previous trial did not cause less streaming in the current trial. Finally, the effect of previous Δf was diminished, though still present, when the silent duration between trials was increased to 5.76 s. The time course of this context effect on streaming implicates the involvement of auditory sensory memory or neural adaptation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Perceptual Integration of Auditory Stimulus Edges: An Illusory Short Tone in Stimulus Patterns Consisting of Two Partly Overlapping Glides.

Two partly overlapping frequency glides can be perceived as consisting of a long pitch trajectory accompanied by a short tone in the temporal middle. It was found that the appearance of this middle tone could not be related to peripheral processes concerned with spectral splatter or combination tones that could have emerged during the overlap of the glides. Furthermore, it was found that the middle tone was perceived even when components of the 2 glides were separated by more than an equivalent rectangular bandwidth at any time during the overlap. The appearance of the middle tone indicates that auditory events can result from the perceptual integration of component parts-that is, stimulus edges-of acoustically different sounds. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Inhibitory influences on asynchrony as a cue for auditory segregation.

A harmonic that begins before the other harmonics contributes less than they do to vowel quality. This reduction can be partly reversed by accompanying the leading portion with a captor tone. This effect is usually interpreted as reflecting perceptual grouping of the captor with the leading portion. Instead, it has recently been proposed that the captor effect depends on broadband inhibition within the central auditory system. A test of psychophysical predictions based on this proposal showed that captor efficacy is (a) maintained for noise-band captors, (b) absent when a captor accompanies a harmonic that continues after the vowel, and (c) maintained for 80 ms or more over a gap between captor offset and vowel onset. These findings support and refine the inhibitory account. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Infant perception of audio-visual speech synchrony.

Three experiments investigated perception of audio-visual (A-V) speech synchrony in 4- to 10-month-old infants. Experiments 1 and 2 used a convergent-operations approach by habituating infants to an audiovisually synchronous syllable (Experiment 1) and then testing for detection of increasing degrees of A-V asynchrony (366, 500, and 666 ms) or by habituating infants to a detectably asynchronous syllable (666 ms; Experiment 2) and then testing for detection of decreasing degrees of asynchrony (500, 366, and 0 ms). Following habituation to the synchronous syllable, infants detected only the largest A-V asynchrony (0 ms vs. 666 ms), whereas following habituation to the asynchronous syllable, infants detected the largest asynchrony (666 ms vs. 0 ms) as well as a smaller one (666 ms vs. 366 ms). Experiment 3 investigated the underlying mechanism of A-V asynchrony detection and indicated that responsiveness was based on a sensitivity to stimulus-energy onsets rather than the dynamic correlation between acoustic and visible utterance attributes. These findings demonstrated that infant perception of A-V speech synchrony is subject to the effects of short-term experience and that it is driven by a low-level, domain-general mechanism. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sonification design for complex work domains: Dimensions and distractors.

Sonification—representing data in sound—is a potential method for supporting human operators who have to monitor dynamic processes. Previous research has investigated a limited number of sound dimensions and has not systematically investigated the impact of dimensional interactions on sonification effectiveness. In three experiments the authors investigated accuracy for identifying changes in six target auditory dimensions of a continuous pulse stream under three conditions: no distractor, one distractor, and five distractors. In Experiment 1 amplitude, frequency, harmonics, speed, tremolo (cycles per pulse), and width were tested. Accuracy and patterns of interaction between the dimensions were mapped. In Experiment 2 the same dimensions were tested but tremolo was operationalized as cycles per second (Hz). The patterns of interaction between the temporal dimensions differed from Experiment 1. In Experiment 3 the amplitude contour of the pulse stream was changed. The dimensions tested were amplitude, frequency, formants, speed, tremolo (cycles per period), and width. Results showed low accuracy for formants and many interactions, both positive and negative between the dimensions. The authors interpret the results in terms of theories of perceptual interference in auditory dimensions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Perceptual Organization and Intelligence: A Further Study": Erratum.

Reports an error in the original article by De Soto and Liebowitz (Journal of Abnormal & Social Psychology, 1956[Nov], 53, 334-337). Some incorrectly calculated probabilities of Type II errors were given. Recalculated probabilities are given in Table 1. These are probabilities of Type II errors for 2-tail t tests of the difference between mean vocabulary scores of high and low perceivers in case of certain hypothetical true differences in various experimental conditions and groupings, as explained in the original article. The probabilities in Table 1 are substantially greater than those given earlier, but low enough that a complete absence of significant t's would be surprising if a large true difference existed. All t's obtained were nonsignificant, and the average difference was in fact in the wrong direction. It may be noted that 1-tail t tests might have been used, since the direction of the difference was hypothesized. One-tail t tests would have had lower probabilities of Type II errors than 2-tail t tests for the hypothetical true differences listed, and would also have yielded uniformly nonsignificant results. (The following abstract of this article originally appeared in record 1958-03650-001). This experiment was a replication of that of Krech and Calvin (Levels of perceptual organization and cognition. J. abnorm. soc. Psychol., 1953, 48, 394-400) using modified techniques. The correlation previously reported by Krech and Calvin between intelligence and perception, did not obtain upon replication. The data confirmed their finding that progression over trials was usually from low to high perceptual organization, but did not show a correlation between perception and stimulus-exposure time from 0.01 to 1.00 second. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sequential grouping of pure-tone percepts evoked by the segregation of components from a complex tone.

A sudden change applied to a single component can cause its segregation from an ongoing complex tone as a pure-tone-like percept. Three experiments examined whether such pure-tone-like percepts are organized into streams by extending the research of Bregman and Rudnicky (1975). Those authors found that listeners struggled to identify the presentation order of 2 pure-tone targets of different frequency when they were flanked by 2 lower frequency “distractors.” Adding a series of matched-frequency “captor” tones, however, improved performance by pulling the distractors into a separate stream from the targets. In the current study, sequences of discrete pure tones were substituted by sequences of brief changes applied to an otherwise constant 1.2-s complex tone. Pure-tone-like percepts were evoked by applying 6-dB increments to individual components of a complex comprising harmonics 1–7 of 300 Hz (Experiment 1) or 0.5-ms changes in interaural time difference to individual components of a log-spaced complex (range 160–905 Hz; Experiment 2). Results were consistent with the earlier study, providing clear evidence that pure-tone-like percepts are organized into streams. Experiment 3 adapted Experiment 1 by presenting a global amplitude increment either synchronous with, or just after, the last captor prior to the 1st distractor. In the former case, for which there was no pure-tone-like percept corresponding to that captor, the captor sequence did not aid performance to the same extent as previously. It is concluded that this change to the captor-tone stream partially resets the stream-formation process, and so the distractors and targets became likely to integrate once more. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Aging and perception of visual form from temporal structure.

In this study, the authors examined age-related changes in participants' ability to perceive global spatial structure defined by temporal fine structure among elements undergoing rapid, irregular change. Participants were also tested on a task involving form recognition from luminance contrast and on a task dependent on perception of 3-dimensional shape from motion. Compared with young adults, older individuals were less sensitive to spatial form defined by temporal structure. In contrast, older observers performed as well as young adults on the other two tasks that were not dependent on temporal sensitivity, ruling out nonsensory factors as the cause of the deficits on the temporal structure task. This selective deficit may reveal reduced sensitivity within the temporal impulse response of the aging visual system, a deficit that could be related to reduced effectiveness of neural inhibition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

What does visual agnosia tell us about perceptual organization and its relationship to object perception?

The authors studied 2 patients, S.M. and R.N., to examine perceptual organization and its relationship to object recognition. Both patients had normal, low-level vision and performed simple grouping operations normally but were unable to apprehend a multielement stimulus as a whole. R.N. failed to derive global structure even under optimal stimulus conditions, was less sensitive to grouping by closure, and was more impaired in object recognition than S.M. These findings suggest that perceptual organization involves a multiplicity of processes, some of which are simpler and are instantiated in lower order areas of visual cortex (e.g., collinearity). Other processes are more complex and rely on higher order visual areas (e.g., closure and shape formation). The failure to exploit these latter configural processes adversely affects object recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Integration of acoustical information in the perception of impacted sound sources: The role of information accuracy and exploitability.

Sound sources are perceived by integrating information from multiple acoustical features. The factors influencing the integration of information are largely unknown. We measured how the perceptual weighting of different features varies with the accuracy of information and with a listener’s ability to exploit it. Participants judged the hardness of two objects whose interaction generates an impact sound: a hammer and a sounding object. In a first discrimination experiment, trained listeners focused on the most accurate information, although with greater difficulty when perceiving the hammer. We inferred a limited exploitability for the most accurate hammer-hardness information. In a second rating experiment, listeners focused on the most accurate information only when estimating sounding-object hardness. In a third rating experiment, we synthesized sounds by independently manipulating source properties that covaried in Experiments 1 and 2: sounding-object hardness and impact properties. Sounding-object hardness perception relied on the most accurate acoustical information, whereas impact-properties influenced more strongly hammer hardness perception. Overall, perceptual weight increased with the accuracy of acoustical information, although information that was not easily exploited was perceptually secondary, even if accurate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The bounds on flexibility in speech perception.

Dutch listeners were exposed to the English theta sound (as in bath), which replaced [f] in /f/-final Dutch words or, for another group, [s] in /s/-final words. A subsequent identity-priming task showed that participants had learned to interpret theta as, respectively, /f/ or /s/. Priming effects were equally strong when the exposure sound was an ambiguous [fs]-mixture and when primes contained unambiguous fricatives. When the exposure sound was signal-correlated noise, listeners interpreted it as the spectrally similar /f/, irrespective of lexical bias during exposure. Perceptual learning about speech is thus constrained by spectral similarity between the input and established phonological categories, but within those limits, adjustments are thorough enough that even nonnative sounds can be treated fully as native sounds. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dependence on external influence: Correlates in perception, attitudes, and judgment.

The hypothesis that people have a generalized tendency to accept or reject external influence is tested in perceptual and conformity situations, using 53 college males as S's. The results show that S's who are highly influenced by the field in one perceptual test perform similarly in other perceptual tests, conformity measures are not significantly interrelated, and field dependent perceptual behavior is associated with high conformity in other tests, particularly autokinetic and attitude change measures. It is suggested that while perceptual performance reflects central tendencies of the person, his performance in specific conformity situations is subject to greater fluctuation as a result of more peripheral factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Selection difficulty and interitem competition are independent factors in rapid visual stream perception.

When observers try to identify successive targets in a visual stream at a rate of 100 ms per item, accuracy for the 2nd target is impaired for intertarget lags of 100-500 ms. Yet, when the same stream is presented more rapidly (e.g., 50 ms per item), this pattern reverses and a 1st-target deficit is obtained. M. C. Potter, A. Staub, and D. H. O'Connor (2002) accounted for these findings with a 2-stage competition theory (detection followed by identification) in which each stage is limited by its own pool of resources. In 5 experiments we varied the items that preceded the 1st target. The results show strong influences of these leading items on the 1st-target deficit, with almost no influence on 2nd-target accuracy. This is interpreted as strong support for multiple factors influencing target accuracy in rapid visual streams (J. Kawahara, J. T. Enns, & V. Di Lollo, 2006). (PsycINFO Database Record (c) 2010 APA, all rights reserved)