Dynamic frequency change influences loudness perception: A central, analytic process.

Three experiments showed that dynamic frequency change influenced loudness. Listeners heard tones that had concurrent frequency and intensity change and tracked loudness while ignoring pitch. Dynamic frequency change significantly influenced loudness. A control experiment showed that the effect depended on dynamic change and was opposite that predicted by static equal loudness contours. In a 3rd experiment, listeners heard white noise intensity change in one ear and harmonic frequency change in the other and tracked the loudness of the noise while ignoring the harmonic tone. Findings suggest that the dynamic interaction of pitch and loudness occurs centrally in the auditory system; is an analytic process; has evolved to take advantage of naturally occurring covariation of frequency and intensity; and reflects a shortcoming of traditional static models of loudness perception in a dynamic natural setting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recalibrating the auditory system: A speed-accuracy analysis of intensity perception.

Recalibration in loudness perception refers to an adaptation-like change in relative responsiveness to auditory signals of different sound frequencies. Listening to relatively weak tones at one frequency and stronger tones at another makes the latter appear softer. The authors showed recalibration not only in magnitude estimates of loudness but also in simple response times (RTs) and choice RTs. RTs depend on sound intensity and may serve as surrogates for loudness. Most important, the speeded classification paradigm also provided measures of errors. RTs and errors can serve jointly to distinguish changes in sensitivity from changes in response criterion. The changes in choice RT under different recalibrating conditions were not accompanied by changes in error rates predicted by the speed-accuracy trade-off. These results lend support to the hypothesis that loudness recalibration does not result from shifting decisional criteria but instead reflects a change in the underlying representation of auditory intensity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Auditory continuity and loudness computation

Sequences composed of alternating bursts of different levels with no silences separating them can give rise to a perception of a continuous sound upon which is superimposed an intermittent stream. These experiments sought to determine how the perceived loudness of the intermittent stream depends on the level difference between higher-level and lower-level bursts in the sequence in cases in which continuity is either heard or not heard. In the main experiment, listeners were asked to adjust the level of continuous or intermittent comparison sequences to match the loudness of components that appeared to be either continuous or intermittent in an alternating-level reference sequence, thus urging them to focus on the two-stream percept. Loudness matches of continuous comparison stimulus were close to physical levels of the lower-level bursts, whereas matches of the intermittent comparison stimulus were well below the physical levels of higher-level bursts. These results are discussed in terms of Bregman's [Auditory Scene Analysis (MIT, Cambridge, MA, 1990)] "old-plus-new" hypothesis: The loudness of the intermittent stream should result from the subtraction of the lower level from the higher level under the assumption that the higher-level burst represents a simultaneous mixture of sounds including the continuation of the lower-level burst. Additional experiments verified that, in the absence of the continuity phenomenon, matched levels were very close to the physical levels and that matches to fixed-level continuous and intermittent sequences were precise. The matching results from the main experiment support predictions of neither classical loudness models that do not take auditory organization processes into account nor schema-based models that presume a selection of information from the higher-level burst that does not affect the perceptual content of this burst. The matched levels fell between predictions of models based on subtraction of acoustic pressure and acoustic power, but were very different from subtraction of loudness measured in sones, suggesting that loudness is computed subsequent to auditory organization processes.     

Intensity discrimination for precedence effect stimuli

When two identical stimuli are presented from two loudspeakers with a brief delay between them, a single image is heard near the source of the leading sound. The delayed sound or echo appears to be suppressed whereas the preceding sound determines perceived location, hence the name, the precedence effect. This study investigated normal-hearing listeners' sensitivity to changes in the intensity of the lagging sound. Pairs of 2-ms white noise bursts, with a 2-ms delay between the onsets of lead and lag, were presented from two loudspeakers 45 degrees left and right of midline in an anechoic chamber. A 2AFC procedure was used to test discrimination of intensity changes in the lead, lag, and both sounds together. The untreated results showed discrimination to be poorest for changes in the lag stimulus. However, when the intensity differences were transformed into predictions of equivalent monaural level based on KEMAR measurements and binaural loudness summation, discrimination for the lag was equal to the other two conditions. A follow-up experiment found that listeners were highly sensitive to the presence of the lag, more sensitive than would be predicted from loudness changes. It is concluded that the precedence effect does not consist of a general suppression or attenuation of the lagging sound, but rather that suppression may be limited to directionality cues.     

Contextual processing of multidimensional and unidimensional auditory stimuli.

Stimulus context (the distribution of stimulus values) can strongly affect both perception and judgment. In 14 experiments, the method of magnitude estimation revealed 2 fundamentally different kinds of context effect in loudness. An assimilative effect dominated when stimuli varied unidimensionally (in intensity only). But a contrastive, or adaptationlike, effect dominated when stimuli varied multidimensionally (in frequency and intensity). In Exp 15, direct loudness comparison revealed a potent, adaptational process specific to the signal frequency. Taken together, these and other results are compatible with the view that loudness perception and judgment reflect the net outcome of 2 different contextual processes: a relatively early (though probably not peripheral) process of perceptual adaptation and a later process of response-dependent assimilation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Unmasking the magnitude estimation response.

Conducted a magnitude estimation of loudness experiment that manipulated the amount of stimulus information (STI) available to 25 university students, using a modified version of informational masking (IFM). A 2nd experiment assessed the effectiveness of IFM in reducing the amount of STI. As the amount of STI was decreased, the magnitude of sequential dependency on previous responses increased, while dependency on previous stimuli decreased. This difference is discussed in terms of L. M. Ward's (see record 1980-27015-001) prediction of an inverse relationship between the amount of STI available to Ss and the magnitude of sequential dependencies on previous stimuli and responses in psychophysical scaling tasks. (French abstract) (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

A longitudinal study of the development of anticipatory nausea and vomiting in cancer chemotherapy patients: The role of absorption and autonomic perception.

Interviewed 70 cancer patients (aged 20–74 yrs) receiving chemotherapy at home before their 2nd treatment session to obtain baseline measures of absorption, autonomic perception, depression, state–trait anxiety, and basic demographic information. Ss were then interviewed before each of their next 6 treatment sessions, at which time measures of depression, state anxiety, severity and duration of postchemotherapy nausea and/or vomiting (PCNV), and experience of anticipatory nausea and/or vomiting (ANV) were obtained. Ss with ANV scored significantly higher on measures of absorption and autonomic perception than Ss who did not develop ANV. Those variables hypothesized to mediate conditioning (i.e., toxicity of treatment drugs, severity of PCNV, levels of state anxiety) accurately predicted which patients developed ANV. Absorption and autonomic perception added significantly to the prediction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Auditory sensory storage in relation to the growth of sensation and acoustic information extraction.

A brief, vivid phase of auditory sensory storage that outlasts the stimulus could be used in perception in two ways: First, all of the neural activity resulting from the stimulus, including that of the sensory store, could contribute to a sensation of growing loudness; second, the sensory store could permit the continued extraction of information about the sound's acoustic properties. This study includes a task for which these two processes lead to different predictions; a third prediction is based on the two processes combined. The task required loudness judgments for two brief tones presented with a variable intertone interval. The results of Experiments 1–3 were as one would expect if both the growth of sensation and information extraction contributed to the pattern of loudness judgments. Experiment 4 strengthened the two-process account by demonstrating the separability of the two processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual primacy of dimensions: Support for a model of dimensional interaction.

Do Ss always process multidimensional stimuli according to psychologically primary dimensions? Our hypothesis is that they do: Primary dimensions provide one component of a new model of dimensional interaction, a model that distinguishes information processed at the level of attributes from information processed at the level of the stimulus. By using sound stimuli created from the dimensions pitch–loudness (Experiments 1 and 2), pitch–timbre (Experiment 3), and loudness–timbre (Experiment 4), we tested performance in selective- and divided-attention tasks at each of three orientations of axes: 0°, 22.5°, and 45°. Each experiment revealed strong evidence of primacy: As axes rotated from 0° to 45°, selective attention deteriorated, but divided attention improved, producing a distinct pattern of convergence. Each experiment also revealed effects of congruity: Attributes from corresponding poles of a dimension (e.g., high pitch and loud) were classified faster than those from noncorresponding poles. The results fit well with our new conception but are inconsistent with other current models of dimensional interaction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Disturbances of loudness perception

This article reviews information on some auditory disorders that have in common a disturbance in loudness perception. The perceptual disturbances in these disorders have interchangeably been labeled "hyperacusis," "dysacusis," or "phonophobia." Our question concerns whether the loudness disturbances associated with these auditory disorders are sufficiently different as not to justify the equivalence implied by the labelling. Emphasis is placed on those articles that have given clear accounts of the phenomenology of the disturbed perceptual experience and have offered testable hypotheses about the mechanisms underlying it. Hypotheses about the origins of disturbed loudness perception are compared with independent experimental and clinical evidence on those mechanisms. The disturbances of loudness perception that occur in cochlear hearing loss, facial nerve paralysis and stapedectomy, and in more "central" disorders are phenomenologically different, have different underlying mechanisms, and merit different labels that most of them do not currently receive.     

Determinants of the remembered utility of aversive sounds.

Retrospective evaluations of aversive episodes were studied in the context of a general model of "judgment by prototype" that has been applied in other situations. Unpleasant sounds of variable loudness and duration were the stimuli. In Experiment 1, continuous reports of annoyance closely tracked variations of noise intensity. Hypotheses about the determinants of retrospective evaluation were examined in Experiment 2. Experiment 3 confirmed a prediction of judgment by prototype: The effects of sound duration and intensity are additive in multitrial experiments. Experiment 4 confirmed a robust preference for aversive episodes that are "improved" by adding a period of reduced aversiveness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Loudness change in response to dynamic acoustic intensity.

Three experiments investigate psychological, methodological, and domain-specific characteristics of loudness change in response to sounds that continuously increase in intensity (up-ramps), relative to sounds that decrease (down-ramps). Timbre (vowel, violin), layer (monotone, chord), and duration (1.8 s, 3.6 s) were manipulated in Experiment 1. Participants judged global loudness change between pairs of spectrally identical up-ramps and down-ramps. It was hypothesized that loudness change is overestimated in up-ramps, relative to down-ramps, using simple speech and musical stimuli. The hypothesis was supported and the proportion of up-ramp overestimation increased with stimulus duration. Experiment 2 investigated recency and a bias for end-levels by presenting paired dynamic stimuli with equivalent end-levels and steady-state controls. Experiment 3 used single stimulus presentations, removing artifacts associated with paired stimuli. Perceptual overestimation of loudness change is influenced by (1) intensity region of the dynamic stimulus; (2) differences in stimulus end-level; (3) order in which paired items are presented; and (4) duration of each item. When methodological artifacts are controlled, overestimation of loudness change in response to up-ramps remains. The relative influence of cognitive and sensory mechanisms is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Range and regression, loudness scales, and loudness processing: Toward a context-bound psychophysics.

How does context affect basic processes of sensory integration and the implicit psychophysical scales that underlie those processes? Five experiments examined how stimulus range and response regression determine characteristics of (1) psychophysical scales for loudness and (2) 3 kinds of intensity summation (binaural loudness summation, summation of loudness between tones widely spaced in frequency, and temporal loudness summation). Context affected the overt loudness scales in that smaller power-function exponents characterized larger vs smaller range of stimulation and characterized magnitude estimation vs magnitude production. More important, however, context simultaneously affected the degree of loudness integration as measured in terms of matching stimulus levels. Thus, stimulus range and scaling procedure influence not only overt response scales but measures of underlying intensity processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prediction of rehabilitation outcomes from psychometric parameters in left hemiplegics.

To test the proposition that an intake, multivariate battery of 42 psychometric predictors can predict duration of stay in rehabilitation and competence in ambulation and self-care, multiple-regression equations were computed for 54 Ss with left hemiplegia, and their retrospective outcome scores were highly accurately predicted. To reduce administration cost, redundant information was deleted. A compact battery of 27 variables was thus obtained, and the program was repeated. Resulting multiple correlations and predictive accuracy were only slightly less than those arrived at with the full battery. A cross-validation study on 15 new Ss yielded essentially identical results. It is concluded that the prediction of outcomes from psychometric measures, taken at the initiation of the rehabilitation program is highly feasible. (24 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Embodied auditory perception: The emotional impact of approaching and receding sound sources.

Research has shown the existence of perceptual and neural bias toward sounds perceived as sources approaching versus receding a listener. It has been suggested that a greater biological salience of approaching auditory sources may account for these effects. In addition, these effects may hold only for those sources critical for our survival. In the present study, we bring support to these hypotheses by quantifying the emotional responses to different sounds with changing intensity patterns. In 2 experiments, participants were exposed to artificial and natural sounds simulating approaching or receding sources. The auditory-induced emotional effect was reflected in the performance of participants in an emotion-related behavioral task, their self-reported emotional experience, and their physiology (electrodermal activity and facial electromyography). The results of this study suggest that approaching unpleasant sound sources evoke more intense emotional responses in listeners than receding ones, whereas such an effect of perceived sound motion does not exist for pleasant or neutral sound sources. The emotional significance attributed to the sound source itself, the loudness of the sound, and loudness change duration seem to be relevant factors in this disparity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Identification variability as a measure of loudness: An application to gender differences.

It is well known that discrimination response variability increases with stimulus intensity, closely related to Weber's Law. It is also an axiom that sensation magnitude increases with stimulus intensity. Following earlier researchers such as Thurstone, Garner, and Durlach and Braida, we explored a new method of exploiting these relationships to estimate the power function exponent relating sound pressure level to loudness, using the accuracy with which listeners could identify the intensity of pure tones. The log standard deviation of the normally distributed identification errors increases linearly with stimulus range in decibels, and the slope, a, of the regression is proportional to the loudness exponent, n. Interestingly, in a demonstration experiment, the loudness exponent estimated in this way is greater for females than for males. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual organization of acoustic stimuli by budgerigars (Melopsittacus undulatus): I. Pure tones.

A new combination of operant conditioning and psychophysical scaling procedures was used to study auditory perception in a small bird. In a same–different discrimination task, budgerigars learned to discriminate among pure tones that varied along one or more acoustic dimensions. Response latencies were used to generate a matrix of interstimulus similarities. Multidimensional scaling procedures were used to arrange these acoustic stimuli in a multidimensional space that supposedly reflects the bird's perceptual organization. For tones that varied in intensity, duration and frequency simultaneously, budgerigars were much more sensitive to frequency changes. From a set of tones that varied only in intensity, it was possible to calculate the growth of loudness with intensity for the budgerigar. For tones that varied only in frequency, budgerigars showed evidence of an "acoustic fovea" for frequency change in the spectral region of 2–4 kHz. Budgerigars and humans also differed in their perceptual grouping of tone sequences that rise, fall, or remain constant in pitch. Surprisingly, budgerigars were much less responsive to pitch contour than were humans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory influences subjective experience: Noise judgments.

The influence of memory on the subjective experience of later events was investigated in two experiments. In one experiment, previously heard sentences and new sentences were presented against a background of white noise that varied in intensity. In a second experiment, a cue set of words was presented either before or after a target set that was embedded in noise. The cue set was either the same as or different from the target set. In both experiments, one of the tasks was to judge the loudness of the noise. The data show that subjects were unable to discount the contribution of memory to perception when judging the noise level. Subjects appeared to base their noise judgments on ease of interpretation of the message presented through noise, with differences in ease being misattributed to a difference in noise level. The advantages of subjective experience as a measure of memory, and the role of subjective experience and misattribution in confusions between cognitive and physical deficits are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Just noticeable differences for intensity and their relation to loudness

The present study examines the relation between the form of the loudness function and the size of the intensity just noticeable difference (jnd). The hypothesis that equal loudnesses at any given sound frequency yield equal-intensity jnd's was examined. In addition, Hellman et al.'s [J. Acoust. Soc. Am. 82, 448-453 (1987)] experiment, which showed that jnd's are independent of the slope of the loudness function was replicated. Threshold shifts and altered loudness-balance functions for 1-kHz tones were produced by using backgrounds of narrow- or wideband noise. The two types of background noise produced intersecting points on loudness-balance functions at which intensity jnd's were obtained. Intensity jnd's were also obtained at equal-loudness levels (corresponding to 30, 40, 50, and 60 dB SL in the unmasked ear) under each of the two noise conditions and in quiet. The results indicate that tones of equal loudness produce approximately equal jnd's and that there is no apparent relation between the slope of the loudness-balance functions and the size of the intensity jnd.     

Basilar membrane nonlinearity and loudness

Loudness matching functions for tones for persons with one shifted-threshold ear (hearing loss and noise-shifted thresholds) and one ear within normal limits were used to derive the presumed basilar membrane (BM) input-output (I/O) function in a normal ear. The comparison was made by assuming that the BM I/O function for the ear with the cochlear threshold shift has a slope of one (a linearized cochlea). The function for the normal ear was derived from the loudness matching function based on this assumption. Comparisons were made for archival basilar membrane data [M. A. Ruggero, N. C. Rich, A. Recio, S. S. Narayan, and L. Robles, J. Acoust. Soc. Am. 101, 2151-2163 (1997)] for chinchilla and archival loudness matches for long-duration tones for persons with various degrees of cochlear hearing loss [F. Miskolczy-Fodor, J. Acoust Soc. Am. 32, 486-492 (1960)]. Comparisons were made also between BM I/O functions and ones derived from loudness matches for persons with unilateral hearing loss simulated by broadband noise. The results show a close resemblance between the basilar membrane I/O function and the function derived from loudness matches for long-duration tones, even though the comparison was between human and chinchilla data. As the degree of threshold shift increases from 40 to 80 dB, the derived BM I/O functions become shallower, with slopes for losses of 60 dB or more falling in the range of values reported for physiological data. Additional measures with short-duration tones in noise show that the slope of the loudness function and the slope of the derived basilar membrane I/O function are associated with the behavioral threshold for the tone. The results for long-duration tones suggest a correspondence between BM displacement and loudness perception in cases of recruitment, but the relation between the degree of loss and the amount of BM compression and the relation between signal duration and compression suggests that other factors, such as the neural population response, may play a role.