Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Loudness Perception”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 649 records · Page 36Linked to original sources

The distinction between integral and separable dimensions: evidence for the integrality of pitch and loudness.

Six experiments are reported that investigated the reality and generality of dimensional integrality (Garner, 1974a) by evaluating whether the auditory dimensions of pitch and loudness are psychologically privileged and whether they combine in an integral fashion. In Experiment 1 we psychophysically scaled the dimensions to ensure that, within the stimulus range used, the perceived value on each dimension would remain constant in the face of variation on the other dimension. In Experiments 2 through 4 we assessed performance by using the converging operations by which Garner defined integrality and separability. Experiment 2 showed that in speeded classification, pitch and loudness lead to facilitation with redundant variation and interference with orthogonal variation. Experiment 3 showed that unspeeded classifications are guided predominantly by overall similarity. Experiment 4 established that the better-fitting metric by which multidimensional similarity is appreciated is Euclidean rather than city block. These results suggest that the dimensions of pitch and loudness combine in an integral fashion. In Experiments 5 and 6 we investigated whether the dimensions of pitch and loudness have a privileged status by assessing the impact of rotating the dimensional axes on performance in a speeded sorting task. Experiment 5 looked at six alternative dimensional orientations to pitch and loudness. If anything, rotating the dimensional axes increased the amount of interference in filtering. In Experiment 6 we assessed an alternative dimensional description of the stimuli based on the dimensions of volume and brightness. We found greater interference when the stimuli varied along the dimensions of volume and brightness than when they varied along the dimensions of pitch and loudness. The fact that the least interference is observed when the stimuli vary along the dimensions of pitch and loudness suggests that these dimensions are the more psychologically valid ones. These findings indicate that integrality is not a "myth," that is, merely a case of psychophysical mismatch. Instead, dimensions that are psychologically real are sometimes processed in a unitary fashion.

Acoustic Stimulation↗

Cross-modal additive conjoint structures and psychophysical scale convergence.

I investigated a variety of issues related to the measurement of the magnitude of psychological experience, especially the magnitude of sensations. Different groups of subjects made pair comparisons, magnitude estimations, and category judgments of the "total sensory magnitude" of light and sound stimuli presented conjointly. Another group judged the dissimilarity of pairs of conjoint stimuli. Various axioms, especially double cancellation, were tested on the resulting rank orders of conjoint stimuli. Judgements of the total magnitude of conjoint combinations of sound and light stimuli formed an additive conjoint structure. Dissimilarity judgments gave rise to a closely related lattice structure. Moreover, various scales of the individual attributes (loudness and brightness) calculated from the two types of judgments of the conjoint stimuli displayed substantial convergence, each scale for a given modality being linear with all other scales for that modality.

Adult↗

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.

Acoustic Stimulation↗

A matching-to-sample feedback technique for training self-control of tinnitus.

Thirty individuals with subjective tinnitus aurium of a variety of types and severity were treated with a matching-to-sample feedback procedure. Following initial evaluation measures, the participants' experienced tinnitus sounds were reproduced audiometrically on all characteristics and were presented to them in the noninvolved ear or in both ears when the tinnitus was binaural. This experimental sound was then reduced in 5 decibel (dB) steps within sessions, and participants had the task of concentrating on reducing the loudness of their tinnitus until a match was achieved between it and the experimental sound at each new dB level. Results showed an overall highly significant difference in dB levels from baseline to final training session. Nearly all participants demonstrated a marked reduction in tinnitus loudness, with 84% reducing it by 10 dB to 62 dB and several eliminating it completely. Individual and pathological variables played no role in training or outcome. Our approach appears to have major advantages over other tinnitus treatment strategies in that it provides direct, significant relief and gives the patient the psychological benefit of gaining control over the problem.

Adult↗

Dimensional interactions in language processing: investigating directions and levels of crosstalk.

In this article we evaluate current models of language processing by testing speeded classification of stimuli comprising one linguistic and one nonlinguistic dimension. Garner interference obtains if subjects are slower to classify attributes on one dimension when an irrelevant dimension is varied orthogonally than when the irrelevant dimension is held constant. With certain linguistic-nonlinguistic pairings (e.g., Experiment 1: the words high and low spoken either loudly or softly), significant Garner interference obtained when either dimension was classified; this indicated two-directional crosstalk. With other pairings (e.g., Experiment 3: spoken vowels and loudness), only the nonlinguistic dimension (e.g., loudness) displayed interference, suggesting unidirectional crosstalk downstream from a phonemic/graphemic level of analysis. Collectively, these results indicate the interaction can occur either within or across levels of information processing, being directed toward either more advanced or more primitive processes. Although poorly explained by all current models of language processing, our results are strikingly inconsistent with models that posit autonomy among levels of processing.

Adult↗

Reflex facilitation of the rabbit nictitating membrane response by an auditory stimulus as a function of interstimulus interval.

The ability of an auditory stimulus to facilitate the amplitude and latency of the unconditioned nictitating membrane (NM) response in rabbits was investigated over a wide range of interstimulus intervals (ISIs) for both delay (Experiments 1-4) and trace (Experiments 3 and 4) procedures. The auditory stimulus was a 1000-Hz tone (T) at either 85 or 95 dB, and the reflex-eliciting stimulus was a 2.0 psi (pounds per square inch) corneal air puff (AP). The results indicate that (a) robust facilitation of the NM response, as measured by an increased amplitude and a reduced latency, can be obtained at long ISIs (2,000-32,000 ms); (b) increasing the tone intensity can increase reflex facilitation of the peak amplitude; (c) at comparable ISIs, delay procedures produce more facilitation of both amplitude and latency than do trace procedures; and (d) when trace procedures are used, amplitude and latency facilitation by a 125-ms tone follows an inverted U-shaped ISI function in which facilitation peaks between 125 and 500 ms, rapidly decreases between 1,000 and 2,000 ms, and disappears by 4,000 ms.

Animals↗

Augmentation of the rat's acoustic startle reflex by nonreflexogenic stimuli.

The size of the rat's acoustic startle reflex was augmented by brief acoustic clicks (which did not themselves elicit startle) presented several milliseconds before the reflex-eliciting stimulus (RS). The same clicks presented after the RS gave relatively weak augmentation that was present in the 1st, but not the 2nd, testing session. Brief footshocks set to 75% of each animal's flinch threshold augmented startle when presented both before and after the RS in both testing sessions. Augmentation by a leading footshock increased with shock intensity and was unaffected by the intensity of the RS. Augmentation by a trailing footshock increased with shock intensity and also with the intensity of the RS. Reflex size is not fixed at the time of reflex elicitation but can be augmented by a later nonreflexogenic stimulus. Reflex augmentation may be caused by the 2nd member of a stimulus pair discharging elements of the reflex pathway that were partially activated by the 1st.

Acoustic Stimulation↗

Subcortical adaptive filtering in the auditory system: associative receptive field plasticity in the dorsal medial geniculate body.

Highly specific subcortical receptive field (RF) plasticity was found in the dorsal division of the guinea pig medial geniculate body during cardiac conditioning to a tonal frequency. There was increased response to the conditioned-stimulus (CS) frequency, and there were decreased responses to adjacent frequencies, especially at the pretraining best frequency (BF), which often resulted in a shift of tuning such that the CS became the new BF. Moreover, 1 hr later the effects were stronger, more sharply tuned, and centered on the CS frequency. A sensitization paradigm produced only broad, general increases of response across the RF. These findings reveal that the analysis of sensory RF dynamics is a valuable approach to understanding the neural mechanisms of information processing in learning and memory.

Animals↗

Receptive field plasticity in the auditory cortex during frequency discrimination training: selective retuning independent of task difficulty.

Classical conditioning is known to induce frequency-specific receptive field (RF) plasticity in the auditory cortex (ACx). This study determined the effects of discrimination training on RFs at two levels of task difficulty. Single unit and cluster discharges were recorded in the ACx of adult guinea pigs trained in a tone-shock frequency discrimination paradigm (30 intermixed trials each of positive conditioned stimulus [CS+]-shock and negative CS [CS-] alone) with behavioral performance indexed by the cardiac deceleration conditioned response (CR). After training in an easy task in which subjects developed discriminative CRs, they were trained in a difficult task (reduced frequency distance between CS+ and CS-) in which they failed to discriminate. However, frequency-specific RF plasticity developed at both levels of task difficulty. Responses to the frequency of the CS+ were increased, whereas responses to other frequencies, including the CS- and the prepotent best frequency (BF) were reduced. In many cases, tuning was shifted such that the frequency of the CS+ became the new BF. The effects were present or stronger after a 1-hr retention interval. The role of RF plasticity in the ACx is discussed for behavioral performance and information storage.

Animals↗

Rapid development of learning-induced receptive field plasticity in the auditory cortex.

Classical conditioning induces frequency-specific receptive field (RF) plasticity in the auditory cortex after relatively brief training (30 trials), characterized by increased response to the frequency of the conditioned stimulus (CS) and decreased responses to other frequencies, including the pretraining best frequency (BF). This experiment determined the development of this CS-specific RF plasticity. Guinea pigs underwent classical conditioning to a tonal frequency, and receptive fields of neurons in the auditory cortex were determined before and after 5, 15, and 30 CS-US (unconditioned stimulus) pairings, as well as 1 hr posttraining. Highly selective RF changes were observed as early as the first 5 training trials. They culminated after 15 trials, then stabilized after 30 trials and 1 hr posttraining. The rapid development of RF plasticity satisfies a criterion for its involvement in the neural bases of a specific associative memory.

Animals↗

Hypoalgesia in response to sensitization during acute noise stress.

Three experiments examined the antinociceptive response shown by rats during exposure to loud noise. Noise exposure resulted in a time-dependent elevation of radiant heat tail flick latency that varied as a function of stimulus intensity. Noise stress hypoalgesia in response to a 90-dB stimulus was blocked by pretreatment with the opioid antagonist naltrexone (0.1-7.0 mg/kg). Systemic administration of midazolam (2 mg/kg) prior to exposure to the stressor attenuated the elevation in tail flick latency. Because topographically similar antinociceptive responses may be elicited with a low intensity noise stimulus that has served as a Pavlovian conditional stimulus for shock, the use of this paradigm may permit direct comparisons of associative and nonassociative fear responses using qualitatively similar auditory stimuli.

Acoustic Stimulation↗

Free-field binaural unmasking in ferrets.

Free-field detection by normal and monaural ferrets of a 500-Hz tone presented over 1 laterally placed loudspeaker and partially masked by narrow-band noise from 2 sources was studied at 2 angular separations of the noise sources (0 degree and 180 degrees). Monaural listening was achieved either by plugging 1 ear canal or removing 1 cochlea. Normal ferrets showed an improvement in detectability of the tone when there was a 180 degrees separation between the noise sources. This unmasking of the tone was abolished in both groups of monaural ferrets, suggesting that the unmasking was due to binaural processing. The development of an animal model demonstrating free-field binaural unmasking, in a species other than humans, will allow investigation into the functional consequences of experimental hearing loss.

Animals↗

Fear potentiation of acoustic startle stimulus-evoked heart rate changes in rats.

The present study examined the extent to which heart rate changes evoked by acoustic startle stimuli are affected by the development of fear during startle testing. The phasic heart rate responses of rats elicited by a 120-dB startle stimulus were characterized by decelerations that habituated across trials and accelerations that developed across trials in a manner that paralleled the development of freezing behavior. A 92-dB stimulus evoked little freezing or tachycardia, yet evoked decelerations of similar magnitude to the 120-dB stimulus. Pharmacological blockade of autonomic activity was used to uncouple freezing from the heart rate accelerations and to show that the accelerations were not an artifact of the habituating decelerations. These results indicate that heart rate responses to nonsignal stimuli depend critically on a rat's previous experience with those stimuli.

Acoustic Stimulation↗

Habituation of prepulse inhibition of the startle reflex using an auditory prepulse close to background noise.

This study examined whether prepulse inhibition habituates with repeated presentation of the prepulse alone. Prepulse inhibition was determined by measuring the decrement in the startle response when the acoustic startle-eliciting stimulus was preceded by an auditory prepulse. Rats received repetitive exposures of the same auditory prepulse alone (experimental condition) and of a visual prepulse alone (control condition). To reduce habituation of startle itself and the possible dishabituating influence the startle stimulus might have on habituation of prepulse inhibition, startle stimulus presentations were infrequently interspersed among a much larger number of prepulse-alone presentations. Stimulus-specific habituation of prepulse inhibition occurred using an auditory prepulse 2.5 dB, but not 13 dB, above background noise. Implications are discussed for the role of prepulse inhibition in sensory gating.

Animals↗

Relationship between auditory intensity discrimination in noise and olivocochlear efferent system activity in humans.

Recent physiological data in animals suggest a role of the medial olivocochlear system (MOCS) in auditory intensity discrimination in noise. In this study, the existence of statistical relationships between intensity difference limens (IDLs) and MOCS functioning was tested in humans. IDLs were measured in conditions of quiet and of ipsilateral, contralateral, and dichotic noise. MOCS functioning was assessed through the contralateral evoked otoacoustic emission (EOAE) amplitude attenuation effect. A first finding was that IDLs measured in the presence of ipsilateral noise were reduced when contralateral noise was added. Furthermore, the observed shift in IDL appeared to be significantly correlated to the contralateral EOAE amplitude attenuation effect. These results support the hypothesis that MOCS functioning plays a role in intensity discrimination in dichotic noise in humans.

Adolescent↗

Intensity discrimination and auditory brainstem responses in cochlear implant and normal-hearing listeners.

Intensity-discrimination limens (IDLs) and auditory brainstem responses (ABRs) were measured as a function of stimulus intensity in 6 cochlear implant (CI) and 8 normal-hearing (NH) listeners. Pulse-train stimuli were delivered electrically to the auditory nerve in CI listeners and acoustically in NH listeners. In CI listeners, the IDLs expressed as Weber fractions decreased monotonically with increasing intensity. In NH listeners, a nonmonotonic IDL function showing a peak a midintensities was observed. ABR wave amplitudes increased regularly with intensity only in CI listeners. Results support the notion that the slight decrease in Weber's fractions with increasing sound intensity--generally referred to as "the near-miss to Weber's law"--is subtended by retrocochlear processes, whereas the increase in Weber's fractions at midlevels--known as "the severe departure from Weber's law"--originates in cochlear mechanisms.

Acoustic Stimulation↗

Loudness scaling and masking in rats.

Two groups of rats were trained on operant discriminations in which the discriminanda were two different sound pressure levels of a 4-kHz tone. The discriminanda were chosen so that the loudness difference between stimuli was equivalent for each group when calculated from a power function with an exponent of .35. Half of each group learned the discrimination in quiet, and the other half learned it in a background of white noise. Within the quiet and the noise conditions, the asymptotic discriminability of stimuli separated by equal loudness differences was equivalent, and discriminability was lower in noise. This is consistent with both the human literature on masked loudness and a model of psychophysical scaling (Pierrel-Sorrentino & Raslear, 1980) in which animals judge perceived differences between stimuli.

Animals↗

Pitch and loudness interact in auditory displays: can the data get lost in the map?

Many auditory displays use acoustic attributes such as frequency, intensity, and spectral content to represent different characteristics of multidimensional data. This study demonstrated a perceptual interaction between dynamic changes in pitch and loudness, as well as perceived asymmetries in directional acoustic change, that distorted the data relations represented in an auditory display. Three experiments showed that changes in loudness can influence pitch change, that changes in pitch can influence loudness change, and that increases in acoustic intensity are judged to change more than equivalent decreases. Within a sonification of stock market data, these characteristics created perceptual distortions in the data set. The results suggest that great care should be exercised when using lower level acoustic dimensions to represent multidimensional data.

Adult↗