Pitch Of Pure Tones Research Articles

An Auditory Stroop Test to Implement in Cognitive Hearing Sciences: Development and Normative Data.

.Objective: This study developed and gained insight in an auditory Stroop test, implementable in cognitive hearing sciences. Methods: An auditory Stroop test was developed and performed in 178 participants, aged between 18 and 69 years. This Auditory Stroop test consisted of two tests: Stroop-tones and Stroop-words whereby the pitch of pure-tones and spoken words (i.e., the words high and low) had to be identified by high or low, respectively. An interference score was calculated as a measure of verbal executive functioning. Regression models were conducted to examine the effect of age, sex, education, awakeness, hearing, as well as visual and verbal working memory, and processing speed on the auditory Stroop scores. Normative data were obtained per age decade. Results: Compared to the visual counterparts, the auditory Stroop outcomes were better predicted by verbal working memory and processing speed. A trend was observed showing a decrease in performances with increasing age. No other participant-related variables had a significant relationship with the auditory Stroop test. Conclusion: This auditory Stroop test was considered a good test for measuring executive functioning using auditory stimuli. Implementing this auditory Stroop test within cognitive hearing sciences will contribute to unravel the auditory-cognitive perspective of speech understanding.

Learning for pitch and melody discrimination in congenital amusia

Congenital amusia is currently thought to be a life-long neurogenetic disorder in music perception, impervious to training in pitch or melody discrimination. This study provides an explicit test of whether amusic deficits can be reduced with training. Twenty amusics and 20 matched controls participated in four sessions of psychophysical training involving either pure-tone (500 Hz) pitch discrimination or a control task of lateralization (interaural level differences for bandpass white noise). Pure-tone pitch discrimination at low, medium, and high frequencies (500, 2000, and 8000 Hz) was measured before and after training (pretest and posttest) to determine the specificity of learning. Melody discrimination was also assessed before and after training using the full Montreal Battery of Evaluation of Amusia, the most widely used standardized test to diagnose amusia. Amusics performed more poorly than controls in pitch but not localization discrimination, but both groups improved with practice on the trained stimuli. Learning was broad, occurring across all three frequencies and melody discrimination for all groups, including those who trained on the non-pitch control task. Following training, 11 of 20 amusics no longer met the global diagnostic criteria for amusia. A separate group of untrained controls (n = 20), who also completed melody discrimination and pretest, improved by an equal amount as trained controls on all measures, suggesting that the bulk of learning for the control group occurred very rapidly from the pretest. Thirty-one trained participants (13 amusics) returned one year later to assess long-term maintenance of pitch and melody discrimination. On average, there was no change in performance between posttest and one-year follow-up, demonstrating that improvements on pitch- and melody-related tasks in amusics and controls can be maintained. The findings indicate that amusia is not always a life-long deficit when using the current standard diagnostic criteria.

Superoptimal Perceptual Integration Suggests a Place-Based Representation of Pitch at High Frequencies.

Pitch, the perceptual correlate of sound repetition rate or frequency, plays an important role in speech perception, music perception, and listening in complex acoustic environments. Despite the perceptual importance of pitch, the neural mechanisms that underlie it remain poorly understood. Although cortical regions responsive to pitch have been identified, little is known about how pitch information is extracted from the inner ear itself. The two primary theories of peripheral pitch coding involve stimulus-driven spike timing, or phase locking, in the auditory nerve (time code), and the spatial distribution of responses along the length of the cochlear partition (place code). To rule out the use of timing information, we tested pitch discrimination of very high-frequency tones (>8 kHz), well beyond the putative limit of phase locking. We found that high-frequency pure-tone discrimination was poor, but when the tones were combined into a harmonic complex, a dramatic improvement in discrimination ability was observed that exceeded performance predicted by the optimal integration of peripheral information from each of the component frequencies. The results are consistent with the existence of pitch-sensitive neurons that rely only on place-based information from multiple harmonically related components. The results also provide evidence against the common assumption that poor high-frequency pure-tone pitch perception is the result of peripheral neural-coding constraints. The finding that place-based spectral coding is sufficient to elicit complex pitch at high frequencies has important implications for the design of future neural prostheses to restore hearing to deaf individuals.SIGNIFICANCE STATEMENT The question of how pitch is represented in the ear has been debated for over a century. Two competing theories involve timing information from neural spikes in the auditory nerve (time code) and the spatial distribution of neural activity along the length of the cochlear partition (place code). By using very high-frequency tones unlikely to be coded via time information, we discovered that information from the individual harmonics is combined so efficiently that performance exceeds theoretical predictions based on the optimal integration of information from each harmonic. The findings have important implications for the design of auditory prostheses because they suggest that enhanced spatial resolution alone may be sufficient to restore pitch via such implants.

Pitch discrimination associated with phonological awareness: Evidence from congenital amusia

Research suggests that musical skills are associated with phonological abilities. To further investigate this association, we examined whether phonological impairments are evident in individuals with poor music abilities. Twenty individuals with congenital amusia and 20 matched controls were assessed on a pure-tone pitch discrimination task, a rhythm discrimination task, and four phonological tests. Amusic participants showed deficits in discriminating pitch and discriminating rhythmic patterns that involve a regular beat. At a group level, these individuals performed similarly to controls on all phonological tests. However, eight amusics with severe pitch impairment, as identified by the pitch discrimination task, exhibited significantly worse performance than all other participants in phonological awareness. A hierarchical regression analysis indicated that pitch discrimination thresholds predicted phonological awareness beyond that predicted by phonological short-term memory and rhythm discrimination. In contrast, our rhythm discrimination task did not predict phonological awareness beyond that predicted by pitch discrimination thresholds. These findings suggest that accurate pitch discrimination is critical for phonological processing. We propose that deficits in early-stage pitch discrimination may be associated with impaired phonological awareness and we discuss the shared role of pitch discrimination for processing music and speech.

Auditory and Visual Crossmodal Correspondences With Haptically Perceived Liquid Viscosity

Past research on crossmodal correspondences as they relate to tactile perception has largely been restricted to solid substances. We investigated the role of haptically explored liquid viscosity in crossmodal correspondences with visually presented luminance, saturation, roundedness, size, number and visual elevation, as well as pure-tone pitch and kiki–bouba-type letter strings. In Experiment 1, we presented two tactile and two visual or auditory stimuli simultaneously, and found significant inter-participant agreement () when pairing viscosity with luminance, saturation, roundedness, size, pitch and letter string type. To assess whether these crossmodal correspondences were relative or absolute, another 32 participants were presented, in Experiment 2, with two tactile stimuli but only one visual/auditory stimulus per trial. In this second experiment, we found that high viscosity was paired with low luminance, roundness, low saturation, and the bouba-type letter string, while low viscosity was paired with high pitch. However, the inverse associations (e.g. low viscosity with high luminance, high viscosity with low pitch) were not significant. These findings indicate that viscosity can be added to the list of dimensions that invoke crossmodal correspondences, and that the majority of crossmodal correspondences involving viscosity are absolute rather than relative, since they appear without explicit comparisons along the visual/auditory dimensions we measured.

INVESTIGATING AUTISTIC TRAITS AND SIMPLE SENSORY PROCESSING

<h3>Introduction</h3> The diagnoses of classic autism and Asperger9s syndrome are thought to represent various points on an ‘autistic spectrum’ that also extends into the neurotypical population. Indeed those with high levels of autistic traits perform more like those with Autism Spectrum Disorder (ASD), than those with low levels, in various psychological tests. There is evidence that those with ASD have enhanced simple sensory processing. Furthermore, there is evidence that the amount of autistic traits is correlated to self-reported sensory over-responsivity in the neurotypical population. A relationship between autistic traits and objective measures of sensory processing has not been investigated. <h3>Method</h3> ‘Vibrotactile frequency discrimination’ and ‘pure tone pitch discrimination’ were measured as objective markers of sensory processing in 23 students. These were compared with autistic traits measured using The Autism Quotient (AQ) Questionnaire. <h3>Results</h3> There were no significant correlations between AQ scores and markers of sensory processing. Therefore the level of autistic traits appears to be unrelated to simple sensory processing in the neurotypical population. <h3>Discussion</h3> The relationship between AQ score and sensory over-reponsiveness may not translate into one between AQ score and sensory processing. Larger sample sizes may be needed to detect this likely subtle correlation.

The temporal coding of pitch: Insights from human electrophysiology

Brian Moore and Roy Patterson have made seminal contributions to our understanding of pitch perception, and in particular the use of temporal pitch information by the auditory brain. The pitch of sounds may be encoded, at least in part, by the tendency of neurons to phase lock to the temporal fine structure and/or envelope of basilar membrane vibration. Direct physiological measures of this mechanism are difficult in humans. However, the gross activity of neurons in the brainstem can be measured using electrophysiological techniques. The frequency-following response (FFR) is an electrophysiological measure of phase locking in the rostral brainstem. The FFR differs between musicians and non-musicians, and across linguistic groups, and is sensitive to short-term pitch discrimination training. These findings suggest that the FFR may reflect neural activity relevant to the encoding of pitch, although other results suggest that it may reflect basic peripheral encoding, rather than the output of a pitch extraction process. Recent results from our laboratory show that combining behavioral and FFR measures can provide insights into the coding of the pitch of pure tones and the coding of musical consonance. The FFR may be a blunt tool, but it provides information that cannot be obtained using other techniques, and this may be particularly useful in investigations of the effects of age and hearing loss on the neural coding of pitch.

Across-Channel Timing Differences as a Potential Code for the Frequency of Pure Tones

When a pure tone or low-numbered harmonic is presented to a listener, the resulting travelling wave in the cochlea slows down at the portion of the basilar membrane (BM) tuned to the input frequency due to the filtering properties of the BM. This slowing is reflected in the phase of the response of neurons across the auditory nerve (AN) array. It has been suggested that the auditory system exploits these across-channel timing differences to encode the pitch of both pure tones and resolved harmonics in complex tones. Here, we report a quantitative analysis of previously published data on the response of guinea pig AN fibres, of a range of characteristic frequencies, to pure tones of different frequencies and levels. We conclude that although the use of across-channel timing cues provides an a priori attractive and plausible means of encoding pitch, many of the most obvious metrics for using that cue produce pitch estimates that are strongly influenced by the overall level and therefore are unlikely to provide a straightforward means for encoding the pitch of pure tones.

Enhanced pure-tone pitch discrimination among persons with autism but not Asperger syndrome

Persons with Autism spectrum disorders (ASD) display atypical perceptual processing in visual and auditory tasks. In vision, Bertone, Mottron, Jelenic, and Faubert (2005) found that enhanced and diminished visual processing is linked to the level of neural complexity required to process stimuli, as proposed in the neural complexity hypothesis. Based on these findings, Samson, Mottron, Jemel, Belin, and Ciocca (2006) proposed to extend the neural complexity hypothesis to the auditory modality. They hypothesized that persons with ASD should display enhanced performance for simple tones that are processed in primary auditory cortical regions, but diminished performance for complex tones that require additional processing in associative auditory regions, in comparison to typically developing individuals. To assess this hypothesis, we designed four auditory discrimination experiments targeting pitch, non-vocal and vocal timbre, and loudness. Stimuli consisted of spectro-temporally simple and complex tones. The participants were adolescents and young adults with autism, Asperger syndrome, and typical developmental histories, all with IQs in the normal range. Consistent with the neural complexity hypothesis and enhanced perceptual functioning model of ASD ( Mottron, Dawson, Soulières, Hubert, & Burack, 2006), the participants with autism, but not with Asperger syndrome, displayed enhanced pitch discrimination for simple tones. However, no discrimination-thresholds differences were found between the participants with ASD and the typically developing persons across spectrally and temporally complex conditions. These findings indicate that enhanced pure-tone pitch discrimination may be a cognitive correlate of speech-delay among persons with ASD. However, auditory discrimination among this group does not appear to be directly contingent on the spectro-temporal complexity of the stimuli.

Verbal memory retrieval engages visual cortex in musicians

As one major line of research on brain plasticity, many imaging studies have been conducted to identify the functional and structural reorganization associated with musical expertise. Based on previous behavioral research, the present study used functional magnetic resonance imaging to identify the neural correlates of superior verbal memory performance in musicians. Participants with and without musical training performed a verbal memory task to first encode a list of words auditorily delivered and then silently recall as many words as possible. They performed in separate blocks a control task involving pure tone pitch judgment. Post-scan recognition test showed better memory performance in musicians than non-musicians. During memory retrieval, the musicians showed significantly greater activations in bilateral though left-lateralized visual cortex relative to the pitch judgment baseline. In comparison, no such visual cortical activations were found in the non-musicians. No group differences were observed during the encoding stage. The results echo a previous report of visual cortical activation during verbal memory retrieval in the absence of any visual sensory stimulation in the blind population, who are also known to possess superior verbal memory. It is suggested that the visual cortex can be recruited to serve as extra memory resources and contributes to the superior verbal memory in special situations. While in the blind population, such cross-modal functional reorganization may be induced by sensory deprivation; in the musicians it may be induced by the long-term and demanding nature of musical training to use as much available neural resources as possible.

A novel physiological mechanism for pitch encoding in monkey primary auditory cortex.

Pitch is a fundamental perceptual attribute of hearing. While auditory cortex is implicated in pitch perception, how pitch is represented at the cortical level remains unclear. The present study examines a novel hypothesis for how the pitch of pure tones and of harmonic complex tones, with or without the fundamental frequency, is encoded in primary auditory cortex (A1): pitch is represented non‐topographically by the temporal distribution of population activity in A1. Sounds of lower pitch evoke a greater proportion of sustained multiunit activity (MUA), relative to initial onset MUA, than sounds of higher pitch, such that the temporal distribution of MUA systematically varies with pitch. Pure tones and harmonic complexes with the same pitch evoke a similar proportion of sustained MUA. The temporal distribution of MUA is largely invariant to changes in stimulus parameters (e.g., level and relative phase) that leave the perceived pitch unchanged. Timing of AEP components recorded in superficial layers of A1 parallels similar pitch‐related changes in AEPs recorded in humans. Coding of perceptual qualities based on the time course of neural activity has been proposed in other sensory modalities (e.g., olfaction) and offers a novel alternative to topographic representations of pitch at the cortical level.

Vocal Analysis Related to Changes in Frequency of Pure Tone Auditory Feedback

PurposeMany studies have shown that subjects show a change of vocal fundamental frequency (F0) when phonating subjects hear their vocal pitch feedback shifted upward or downward. This study was performed to demonstrate whether vocal parameters [F0, intensity, jitter, shimmer, and noise to harmonic ratio (NHR)] in normal males respond to changes in frequency of pure tone masking.Materials and MethodsTwenty healthy male subjects participated in this study. Subjects vocalized /a/ vowel sounds while listening to a pitch-shift pure tone through headphones (upward pitch-shift in succession: 1kHz to 2 kHz and 1 kHz to 4 kHz at 50 dB or 80 dB, respectively, downward pitch-shift in succession: 1 kHz to 250 Hz and 1 kH to 500 Hz at 50 dB or 80 dB, respectively).ResultsVocal intensity, F0, was increased, whereas jitter was decreased as the pitch of pure tone was shifted upward. However, there was no correlation between shimmer and NHR with pitch-shift feedback for pure tones. Unlike vocal pitch-shift feedback in other studies, upward pitch-shift feedback of pure tones caused the vocal F0 and intensity to change in the same direction as pitch-shift.ConclusionThe results of this study demonstrated that auditory kinesthetic feedback is affected by pitch-shift in pure tone.

Temporal integration in absolute identification of musical pitch

The effect of stimulus duration on absolute identification of musical pitch was measured in a single-interval 12-alternative forced-choice task. Stimuli consisted of pure tones selected randomly on each trial from a set of 60 logarithmically spaced musical note frequencies from 65.4 to 1975.5 Hz (C2–B6). Stimulus durations were 5, 10, 25, 50, 100, and 1000 ms. Six absolute-pitch musicians identified the pitch of pure tones without feedback, reference sounds, or practice trials. Results showed that a 5 ms stimulus is sufficient for producing statistically significant above chance performance. Performance monotonically increased up to the longest duration tested (1000 ms). Higher octave stimuli produced better performance, though the rate of improvement declined with increasing octave number. Normalization by the number of waveform cycles showed that 4 cycles are sufficient for absolute-pitch identification. Restricting stimuli to a fixed-cycle waveform instead of a fixed-duration still produced monotonic improvements in performance as a function of stimulus octave, demonstrating that better performance at higher frequencies does not exclusively result from a larger number of waveform cycles. Several trends in the data were well predicted by an autocorrelation model of pitch extraction, though the model outperformed observed performance at short durations suggesting an inability to make optimal use of available periodicity information in very brief tones.

Changing pitch induced visual motion illusion

We often associate moving objects and changing pitch, e.g., falling stones with descending, and launching rockets with ascending pitch, even when these sounds do not happen in the real-world. The reason for this is unknown. Here we report an illusion in which auditory stimuli with no apparent spatial and motion information [[1–3]] alter human visual motion perception. Subjects made a two alternative forced choice (upward (Vup) or downward (Vdown) visual motion perception) while presented with two superimposed, oppositely moving gratings (experiment 1), accompanied by either an ascending or a descending pitch of pure tone, or broad-band noise (Figure 1A). Gratings with ambiguous motion accompanied by ascending pitch were more likely to be perceived as an upward motion, those accompanied by descending pitch as a downward motion, whereas noise caused no directional bias.

Does static ear canal pressure influence pure tone pitch perception?

ObjectiveThat static ear canal air pressure (ECP) influences the frequency of spontaneous otoacoustic emissions (SOAEs) suggests that it may influence intracochlear, in addition to middle ear, processes. A previous study suggested that ECP influences pure tone pitch perception at 1,000 Hz, which was interpreted as indicating an effect on the cochlear place-frequency map. The present study extended investigations of this effect to 500 and 4,000 Hz.Materials and MethodsNine normal-hearing listeners performed interaural pitch matching with monaural ECPs of 0 and -300 daPa.ResultsSome indications of a small downward pitch shift (mean 0.2%) at 500 Hz were observed, which were marginally statistically significant at the 5% level. No pitch shifts were observed at 4,000 Hz.ConclusionsECP does not influence pitch to the extent suggested previously or by SOAE frequency shifts. No evidence was found to support the notion that ECP influences the place-frequency map.

Complex sound source determination: Behavioral studies on goldfish

A series of experiments is reported on complex sound perception in goldfish using classical respiratory conditioning and a stimulus generalization paradigm. In general, animals are initially conditioned to a simple or complex sound, and then tested for generalization to novel sounds that differ systematically from the conditioning sound along one or more stimulus dimensions. Generalization gradients to the novel sound set indicate what sounds are perceived as similar or dissimilar, and what features of sounds are analyzed or attended to during conditioning and generalization testing. So far, these kinds of experiments have demonstrated perceptual dimensions in goldfish that resemble the dimensions of pure tone pitch, complex pitch, timbre, and roughness as perceived by humans. In addition, several experiments have revealed auditory stream segregation in goldfish that resembles that demonstrated for human listeners. It is concluded that goldfish share with humans a sense of hearing that is primitive for vertebrates, and is likely shared with most other vertebrate species. At a qualitative level, at least, goldfish know what we know about sounds and their sources. [Work supported by the NIH, NIDCD.]

Non-impaired auditory phase locking in dyslexic adults.

Dyslexic adults have profound difficulties in discriminating rapidly presented sound sequences. To test whether these deficits might be caused by impaired neuronal phase locking to the envelopes of the sound stimuli, 20 normal-reading and 13 dyslexic adults discriminated pitches of pure tones at approximately 1 kHz (producing spectral pitch due to place coding in the cochlea) and of approximately 80 Hz amplitude modulations of white noise (producing periodicity pitch based on temporal information only). We proposed that a specific deficit in phase locking would result in a worse ability to discriminate periodicity than spectral pitch. The dyslexics were significantly less accurate than the control subjects in discriminating both spectral and periodicity pitch stimuli but their performance was not disproportionally worse in the periodicity pitch task. Thus it seems that impaired neuronal phase-locking cannot explain the problems dyslexics face in processing of rapid sound sequences.

The Mel Scale's disqualifying bias and a consistency of pitch-difference equisections in 1956 with equal cochlear distances and equal frequency ratios

In 1956, Stevens ‘commissioned’ an experiment to equisect a pitch difference between two tones. Results appear to reveal a methodological flaw that would invalidate the Mel Scale (Stevens and Volkmann, 1940). Stevens sought to distinguish sensory continua, e.g., loudness and pitch, on various criteria. He expected that the pitch continuum would not exhibit ‘hysteresis’; i.e., that subjects dividing a pitch difference (Δf) into equal-appearing parts would not set dividing frequencies higher when listening to notes in ascending order than in descending order. Seven subjects equisected a pitch difference, between tones of 400 and 7000 Hz, into equal-seeming parts by adjusting the frequencies of three intermediate tones. All seven exhibited hysteresis, contrary to expectation. This outcome bears on other issues. Years prior, Stevens suggested that equal pitch differences might correspond to equal cochlear distances, but not to equal frequency ratios nor to equal musical intervals (Stevens and Davis, 1938; Stevens and Volkmann, 1940). In 1960 (reported now), both the 1940 Mel Scale and the equal pitch differences of 1956 were compared to equal cochlear distances, using a frequency-position function that fitted Békésy's cochlear map (Greenwood 1961, 1990). When ascending and descending settings were combined to contra-pose biases, equal pitch differences did coincide with equal distances — which the Mel Scale did not. Further, the biased ascending-order data coincided with the Mel Scale, suggesting the Mel Scale was similarly biased. Thus, the combined-order equal pitch differences of 1956 — but not the Mel Scale — are consistent with equal cochlear distances. However, since the map between 400 and 7000 Hz is nearly logarithmic, equal frequency ratios also approximate equal distances. Ironically, above 400 Hz, Békésy's map and Stevens' equal-distance hypothesis jointly imply that musical intervals will nearly agree with equal pitch differences, which Stevens thought he had disconfirmed. However, given Békésy's map, only near the cochlear apex will equal distances not approximate equal frequency ratios; and Pratt's (Pratt, 1928) bisections of Δfs greater than an octave indicated that equal pitch differences, on average, did agree with equal distances. However, they did so for only two of four subjects and coincided instead with equal frequency ratios for one musical subject. Historical distinctions suggest that between the parts of equisected Δfs subjective equivalence may be of two kinds — one linked to musical intervals, leading to equal frequency ratios; a second linked to ‘tone-height’ and ‘distance’, leading to deviations from equal frequency ratios near the apex, though not appreciably if equisected Δfs are less than an octave (or if perhaps subjects are musicians). Data of other kinds suggest that, if pure-tone pitch height were a function of place, the place could be the apical excitation-pattern edge, in any case not a maximum, which in neural data shifts and disappears with tone level.

Sparing of short-term memory in an amnesic patient: implications for strength theory of memory

Abstract Short-term recognition memory for single-digit numbers, three-digit numbers, and the pitch of pure tones was studied in a subject (H.M.) who appears to possess normal short- term memory, but to be almost completely lacking in the ability to form new long-term memory traces. The primary purpose was to test the short-term memory component of a dual-trace strength theory developed for normal subjects. To a first approximation, H.M.'s trace-strength decay curves are exponential, as postulated by strength theory for short-term memory. Furthermore, the rate of decay of this trace for H.M. is well within the range of normal subjects. These findings agree with previous findings on H.M. in support of a dual-trace theory of memory. More particularly, the present findings support the strength theory of memory proposed by WICKELGREN and NORMAN [15].

Auditory factors in obscure auditory dysfunction

Obscure auditory dysfunction (OAD), defined as a self-reported difficulty in understanding speech in noise by persons with normal audiograms and no other obvious causes, is commonly seen in clinical settings [G. H. Saunders and M. P. Haggard, Ear Hear. 10, 200–208]. In an attempt to characterize the hearing difficulties experienced by this population, measures of frequency selectivity, complex and pure-tone discrimination and gap detection were obtained, as well as speech, audiometric, and case history data. Results indicated impaired frequency selectivity at low frequencies, especially at 100 Hz and higher than normal thresholds for complex- and pure-tone pitch and gap detection also at the lower frequencies. Speech reception thresholds in noise were not consistently higher than for normal listeners. [Research supported by the American Speech-Language-Hearing Foundation, NC Regional Chapter of the Acoustical Society of America, and the Andrus Foundation.]