Pitch Feedback Research Articles

“Deafness” effects in detecting alterations to auditory feedback during sequence production

Past research has shown that when discrete responses are associated with a perceptual goal, performers may have difficulty detecting stimuli that are commensurate with that goal. Three experiments are reported here that test whether such effects extend to sequence production. In Experiment 1, participants performed 8-note melodies repeatedly, and on each trial a single tone could be altered with respect to its pitch and/or synchrony with actions. Results suggested a selective deficit of detection when feedback pitch was unchanged and the event was slightly delayed. Experiment 2 showed that this "deafness" to feedback is limited to rhythmic motor tasks that require sequencing, in that similar effects did not emerge when participants produced pitch sequences by tapping a single key repeatedly. A third experiment demonstrated similar results to Experiment 1 when the mapping of keys to pitches on the keyboard was reversed. Taken together, results suggest a selective deafness to response-congruent delayed feedback, consistent with the idea that performers suppress previously planned events during production.

Developmental sex-specific change in auditory–vocal integration: ERP evidence in children

ObjectiveThe present event-related potential (ERP) study examined the developmental mechanisms of auditory–vocal integration in normally developing children. Neurophysiological responses to altered auditory feedback were recorded to determine whether they are affected by age and sex. MethodForty-two children were pairwise matched for sex and were divided into a group of younger (10–12years) and a group of older (13–15years) children. Twenty healthy young adults (20–25years) also participated in the experiment. ERPs were recorded from the participants who heard their voice pitch feedback unexpectedly shifted −50, −100, or −200 cents during sustained vocalization. ResultsP1 amplitudes became smaller as subjects increased in age from childhood to adulthood, and males produced larger N1 amplitudes than females. An age-related decrease in the P1–N1 latencies was also found: latencies were shorter in young adults than in school children. A complex age-by-sex interaction was found for the P2 component, where an age-related increase in P2 amplitudes existed only in girls, and boys produced longer P2 latencies than girls but only in the older children. ConclusionsThese findings demonstrate that neurophysiological responses to pitch errors in voice auditory feedback depend on age and sex in normally developing children. SignificanceThe present study provides evidence that there is a sex-specific development of the neural mechanisms involved in auditory–vocal integration.

Opposing and following vocal responses to pitch-shifted auditory feedback: Evidence for different mechanisms of voice pitch control

The present study describes a technique for analysis of vocal responses to auditory feedback pitch perturbations in which individual trials are first sorted according to response direction and then separately averaged in groups of upward or downward responses. In experiment 1, the stimulus direction was predictable (all upward) but magnitude was randomized between +100, +200, or +500 cents (unpredictable). Results showed that pitch-shift stimuli (PSS) of +100 and +200 cents elicited significantly larger opposing (compensatory) responses than +500 cent stimuli, but no such effect was observed for "following" responses. In experiment 2, subjects were tested in three blocks of trials where for the first two, PSS magnitude and direction were predictable (block 1+100 and block 2-100 cents), and in block 3, the magnitude was predictable (±100 cents) but direction was randomized (upward or downward). Results showed there were slightly more opposing than following responses for predictable PSS direction, but randomized directions led to significantly more opposing than following responses. Results suggest that predictability of stimulus direction and magnitude can modulate vocal responses to feedback pitch perturbations. The function and causes of the opposing and following responses are unknown, but there may be two different neural mechanisms involved in their production.

ERP correlates of language-specific processing of auditory pitch feedback during self-vocalization

The present study investigated whether the neural correlates for auditory feedback control of vocal pitch can be shaped by tone language experience. Event-related potentials (P2/N1) were recorded from adult native speakers of Mandarin and Cantonese who heard their voice auditory feedback shifted in pitch by −50, −100, −200, or −500cents when they sustained the vowel sound /u/. Cantonese speakers produced larger P2 amplitudes to −200 or −500cents stimuli than Mandarin speakers, but this language effect failed to reach significance in the case of −50 or −100cents. Moreover, Mandarin speakers produced shorter N1 latencies over the left hemisphere than the right hemisphere, whereas Cantonese speakers did not. These findings demonstrate that neural processing of auditory pitch feedback in vocal motor control is subject to language-dependent neural plasticity, suggesting that cortical mechanisms of auditory–vocal integration can be shaped by tone language experience.

"The dynamics of disruption from altered auditory feedback: Further evidence for a dissociation of sequencing and timing": Correction to Pfordresher and Kulpa (2011).

Reports an error in dynamics of disruption from altered auditory feedback: Further evidence for a dissociation of sequencing and by Peter Q. Pfordresher and J. D. Kulpa (Journal of Experimental Psychology: Human Perception and Performance, 2011[Jun], Vol 37[3], 949-967). In Figure 8 the y-axes for panels A, B, C, and D should read Mean error instead of Mean IRI. In addition, in the caption for Figure 8 the sentence data point represents the mean error rate across participants beginning at that serial position, ending at the next serial position should read data point represents the mean error rate across participants at that serial position. (The following abstract of the original article appeared in record 2011-07484-001.) Three experiments were designed to test whether perception and action are coordinated in a way that distinguishes sequencing from timing (Pfordresher, 2003). Each experiment incorporated a trial design in which altered auditory feedback (AAF) was presented for varying lengths of time and then withdrawn. Experiments 1 and 2 included AAF that resulted in action-effect asynchronies (delayed auditory feedback) during simple tapping (Experiment 1) and melody production (Experiment 2). Asynchronous AAF immediately slowed production; this effect then diminished rapidly after removal of AAF. By contrast, sequential alterations of feedback pitch during melody production (Experiment 3) had an effect that varied over successive presentations of AAF (by increasing error rates) that lasted after its withdrawal. The presence of auditory feedback after withdrawal of asynchronous AAF (Experiments 1 and 2) led to overcompensation of timing, whereas the presence of auditory feedback did not influence performance after withdrawal of AAF in Experiment 3. Based on these results, we suggest that asynchronous AAF perturbs the phase of an internal timekeeper, whereas alterations to feedback pitch over time degrade the internal representation of sequence structure. (PsycINFO Database Record (c) 2011 APA, all rights reserved). Language: en

Effects of altered auditory feedback across effector systems: Production of melodies by keyboard and singing

We report an experiment that tested whether effects of altered auditory feedback (AAF) during piano performance differ from its effects during singing. These effector systems differ with respect to the mapping between motor gestures and pitch content of auditory feedback. Whereas this action-effect mapping is highly reliable during phonation in any vocal motor task (singing or speaking), mapping between finger movements and pitch occurs only in limited situations, such as piano playing. Effects of AAF in both tasks replicated results previously found for keyboard performance (Pfordresher, 2003), in that asynchronous (delayed) feedback slowed timing whereas alterations to feedback pitch increased error rates, and the effect of asynchronous feedback was similar in magnitude across tasks. However, manipulations of feedback pitch had larger effects on singing than on keyboard production, suggesting effector-specific differences in sensitivity to action-effect mapping with respect to feedback content. These results support the view that disruption from AAF is based on abstract, effector independent, response–effect associations but that the strength of associations differs across effector systems.

Auditory Feedback Control of Vocal Pitch during Sustained Vocalization: A Cross-Sectional Study of Adult Aging

BackgroundAuditory feedback has been demonstrated to play an important role in the control of voice fundamental frequency (F0), but the mechanisms underlying the processing of auditory feedback remain poorly understood. It has been well documented that young adults can use auditory feedback to stabilize their voice F0 by making compensatory responses to perturbations they hear in their vocal pitch feedback. However, little is known about the effects of aging on the processing of audio-vocal feedback during vocalization.Methodology/Principal FindingsIn the present study, we recruited adults who were between 19 and 75 years of age and divided them into five age groups. Using a pitch-shift paradigm, the pitch of their vocal feedback was unexpectedly shifted ±50 or ±100 cents during sustained vocalization of the vowel sound/u/. Compensatory vocal F0 response magnitudes and latencies to pitch feedback perturbations were examined. A significant effect of age was found such that response magnitudes increased with increasing age until maximal values were reached for adults 51–60 years of age and then decreased for adults 61–75 years of age. Adults 51–60 years of age were also more sensitive to the direction and magnitude of the pitch feedback perturbations compared to younger adults.ConclusionThese findings demonstrate that the pitch-shift reflex systematically changes across the adult lifespan. Understanding aging-related changes to the role of auditory feedback is critically important for our theoretical understanding of speech production and the clinical applications of that knowledge.

Re-examining the effects of perturbation magnitude, direction, and duration on the pitch-shift reflex.

Comparing average voice fundamental frequency (F0) responses to pitch-shifted auditory feedback has revealed effects of some stimulus parameters, but not of others. We hypothesize that some stimulus effects on pitch-shift reflex characteristics are spurious, the result of differences in the incidence of the pitch-shift reflex rather than its inherent characteristics. Using a template correlation analysis technique that allows the pitch-shift reflex to be identified in individual trials, the effects of stimulus magnitude, direction, and duration were re-examined. We presented 30 healthy adults with auditory feedback pitch shifts during sustained phonation of the vowel /u/. Pitch shifts were all combinations of magnitude (50, 300, and 600 cents), Direction (up and down) and duration (100 and 500 ms) for a total of 12 conditions. Results indicate significant effects of pitch perturbation magnitude and direction on the incidence of the pitch-shift reflex. Implications for our understanding of voice F0 responses to changes in auditory feedback are discussed.

The dynamics of disruption from altered auditory feedback: Further evidence for a dissociation of sequencing and timing.

Three experiments were designed to test whether perception and action are coordinated in a way that distinguishes sequencing from timing (Pfordresher, 2003). Each experiment incorporated a trial design in which altered auditory feedback (AAF) was presented for varying lengths of time and then withdrawn. Experiments 1 and 2 included AAF that resulted in action-effect asynchronies (delayed auditory feedback) during simple tapping (Experiment 1) and melody production (Experiment 2). Asynchronous AAF immediately slowed production; this effect then diminished rapidly after removal of AAF. By contrast, sequential alterations of feedback pitch during melody production (Experiment 3) had an effect that varied over successive presentations of AAF (by increasing error rates) that lasted after its withdrawal. The presence of auditory feedback after withdrawal of asynchronous AAF (Experiments 1 and 2) led to overcompensation of timing, whereas the presence of auditory feedback did not influence performance after withdrawal of AAF in Experiment 3. Based on these results, we suggest that asynchronous AAF perturbs the phase of an internal timekeeper, whereas alterations to feedback pitch over time degrade the internal representation of sequence structure.

Sex-related differences in vocal responses to pitch feedback perturbations during sustained vocalization

The present study assessed the effect of sex on voice fundamental frequency (F(0)) responses to pitch feedback perturbations during sustained vocalization. Sixty-four native-Mandarin speakers heard their voice pitch feedback shifted at ± 50, ± 100, or ± 200 cents for 200 ms, five times during each vocalization. The results showed that, as compared to female speakers, male speakers produced significantly larger but slower vocal responses to the pitch-shifted stimuli. These findings reveal a modulation of vocal response as a function of sex, and suggest that there may be a differential processing of vocal pitch feedback perturbations between men and women.

Differential effects of perturbation direction and magnitude on the neural processing of voice pitch feedback

Objective The present study examined the differential effects of voice auditory feedback perturbation direction and magnitude on voice fundamental frequency (F 0) responses and event-related potentials (ERPs) from EEG electrodes on the scalp. Methods The voice F 0 responses and N1 and P2 components of ERPs were examined from 12 right-handed speakers when they sustained a vowel phonation and their mid-utterance voice pitch feedback was shifted ±100, ±200, and ±500 cents with 200 ms duration. Results Downward voice pitch feedback perturbations led to larger voice F 0 responses than upward perturbations. The amplitudes of N1 and P2 components were larger for downward compared with upward pitch-shifts for 200 and 500 cents stimulus magnitudes. Shorter N1 and P2 latencies were also associated with larger magnitudes of pitch feedback perturbations. Conclusions Corresponding changes in vocal and neural responses to upward and downward voice pitch feedback perturbations suggest that the N1 and P2 components of ERPs reflect neural concomitants of the vocal responses. Significance The findings of interactive effects between the magnitude and direction of voice feedback pitch perturbation on N1 and P2 ERP components indicate that the neural mechanisms underlying error detection and correction in voice pitch auditory feedback are differentially sensitive to both the magnitude and direction of pitch perturbations.

Auditory feedback control of voice fundamental frequency in school children

The present study was intended to address how the online control of voice fundamental frequency (F(0)) during vocalization develops from school children to young adults. Nineteen school children (7-12 years old) and twenty-one young adults (19-27 years old) participated in this experiment. They were asked to sustain a vowel sound /u/ while their voice pitch feedback was randomly shifted (+/-50, +/-100, +/-200, and +/-500 cents) and fed back to them instantaneously over headphones. Results showed that school children produced significantly larger but slower compensatory responses to voice pitch feedback perturbations than young adults. Response latencies became longer with the increase in pitch perturbation magnitude, but no systematic changes were found as a function of stimulus direction. In addition, the number of responses "following" the stimulus direction across different stimulus magnitudes for school children was greater than for young adults. These findings demonstrate developmental changes of vocal responses to pitch feedback perturbations during vocalization from school children to young adults, and suggest that vocal responses can serve as an objective index of the maturation of the audio-vocal system.

Enhanced neural responses to self-triggered voice pitch feedback perturbations

This study investigated the effect of self-triggered voice fundamental frequency (F0) feedback perturbation on auditory event-related potentials (ERPs) during vocalization and listening. Auditory ERPs were examined in response to self-triggered and computer-triggered -200 cents pitch-shift stimuli while participants vocalized or listened to the playback of their self-vocalizations. The stimuli were either presented with a delay of 500-1000 ms after the participants pressed a button or delivered by a computer with an interstimulus interval of 500-1000 ms. Results showed that self-triggered stimuli elicited larger ERPs compared with computer-triggered stimuli during both vocalization and listening conditions. These findings suggest that self-triggered perturbation of self-vocalization auditory feedback may enhance auditory responses to voice feedback pitch perturbation during vocalization and listening.

Vocal pitch regulation depends on the baseline voice F0 feedback: An ERP study for investigating the role of auditory feedback for voice pitch error correction.

Voice production and control require neural interactions between the vocal motor and auditory mechanisms. The comparison between the incoming auditory feedback and the predicted sensory input (efference copies) from a self-produced vocalization allows the detection of feedback mismatches for voice error detection and correction. However, the sensitivity of the audio-vocal system for feedback mismatch detection seems to depend on the extent of feedback deviation from the predicted vocal output. The present study investigated this effect by examining event-related potentials (ERPs) in response to a +100-cent voice feedback pitch perturbation stimulus while the extent of pre-stimulus (baseline) feedback pitch deviation was randomly manipulated at 0, 50, 100, 200, and 400 cents. Results showed that the neural responses to +100-cent pitch-shift stimuli grew systematically larger as the extent of pre-stimulus baseline pitch deviation became smaller. This finding suggests that the extent of disparity between the predicted and incoming sensory feedback of self-produced voice can affect the neural tuning processes that adjust the sensitivity of the audio-vocal mechanisms for voice pitch error detection and correction. Lower sensitivity to larger feedback mismatches may imply robustness against the disruptive effect of highly deviant or externally generated sounds during vocal production and control.

Online monitoring of auditory feedback is sensitive to language experience.

It has been demonstrated that vocal responses to pitch perturbations vary as a function of stimulus parameter and can be modulated according to the specific demands of vocal task. The purpose of this cross-language study was to examine whether the online monitoring of auditory feedback is sensitive to language experience during vowel phonation. Native speakers of Cantonese and Mandarin participated in the experiments. They were asked to vocalize a vowel sound /u/ at their conversational pitch, during which their voice pitch feedback was unexpectedly shifted (±50, ±100, ±200, or ±500 cents, 200 ms duration) and fed back to them over headphones. The results showed that, as compared to previous findings in English speakers [Chen et al. (2007)], both Mandarin and Cantonese speakers produced smaller but faster responses to pitch perturbations. In addition, Mandarin speakers produced larger response magnitudes than Cantonese speakers, and the modulation of response magnitudes as a function of stimulus magnitude was observed in Cantonese but not in Mandarin speakers. These findings demonstrate that voice F0 control is language dependent. Further, the different patterns of vocal responses between Mandarin and Cantonese speakers indicate that this highly automatic feedback mechanism works within the specific tonal system of each language.

2008 Zemlin Award in Speech Sciences Memorial Lecture: The Role of Auditory Feedback for the Control of Voice Fundamental Frequency and Amplitude

Abstract Previous research has failed to identify precise neural mechanisms involved in auditory feedback regulation of vocalization. The goal of this research project was to improve our understanding of neural mechanisms controlling the voice. Participants were instructed to sustain a vowel or repeat phrases during which perturbations in voice pitch or loudness feedback were presented. Voice signal averaging, neuroimaging, laryngeal electromyography, and cortical event-related potential techniques were used to measure vocal and neural responses to perturbed feedback. Pitch- and loudness-shifted voice feedback triggers small automatic corrective responses in voice fundamental frequency and amplitude during vowel or speech production. Larger responses during speech suggest task modulation of these responses. Larger responses were also recorded in individuals with Parkinson's disease and children with autism than in normal controls. Neural recording techniques revealed cortical activation during these responses. Cortical mechanisms are involved in generating corrective vocal responses to perturbations in voice auditory feedback. This system helps control the voice during speech and dynamically adjusts responses to meet vocal goals. Abnormally large responses in individuals with Parkinson's disease and autism suggest that the audio-vocal mechanisms just described may be involved in the speech and vocalizations of these individuals as well.

Vocalization-induced enhancement of the auditory cortex responsiveness during voice F0 feedback perturbation

The present study investigated whether self-vocalization enhances auditory neural responsiveness to voice pitch feedback perturbation and how this vocalization-induced neural modulation can be affected by the extent of the feedback deviation. Event-related potentials (ERPs) were recorded in 15 subjects in response to +100, +200 and +500 cents pitch-shifted voice auditory feedback during active vocalization and passive listening to the playback of the self-produced vocalizations. The amplitude of the evoked P(1) (latency: 73.51 ms) and P(2) (latency: 199.55 ms) ERP components in response to feedback perturbation were significantly larger during vocalization than listening. The difference between P(2) peak amplitudes during vocalization vs. listening was shown to be significantly larger for +100 than +500 cents stimulus. Results indicate that the human auditory cortex is more responsive to voice F(0) feedback perturbations during vocalization than passive listening. Greater vocalization-induced enhancement of the auditory responsiveness to smaller feedback perturbations may imply that the audio-vocal system detects and corrects for errors in vocal production that closely match the expected vocal output. Findings of this study support previous suggestions regarding the enhanced auditory sensitivity to feedback alterations during self-vocalization, which may serve the purpose of feedback-based monitoring of one's voice.

Effect of stimulus onset delay on auditory cortex neural responses to voice pitch feedback perturbation.

It has previously been shown that the auditory neural responses to voice F0 feedback perturbation are suppressed during active vocalization compared to passive listening to the playback. However, a study in primates showed that the vocalization‐induced suppression enhances auditory sensitivity to feedback perturbation. This evidence suggests that the cortical neural responses to self‐vocalization reflect suppression to vocal onset and excitation in response to perturbations in voice pitch feedback. In this study, we investigated the effect of stimulus onset delay on cortical neural responses to voice F0 feedback perturbation. Event‐related potentials (ERPs) were recorded in human subjects in response to simultaneous (0 ms) and delayed (500 ms) PSS (+200 cents) during active vocalization and passive listening conditions. Results showed that, for the delayed PSS, the P200 peak magnitude was larger during vocalization compared with passive listening. This finding suggests that vocalization enhances auditory ...

Attenuation of vocal responses to pitch perturbations during Mandarin speech

The effect of stimulus timing on vocal responses to pitch-shifted feedback was investigated in different intonation patterns during Mandarin speech production. While speaking a four-word sentence consisting of the high-level tone, where the fundamental frequency (F(0)) of the final word was either increased (question intonation) or slightly falling (statement intonation), pitch-shift stimuli (+/-100 cents, 200 ms duration) were presented at three different times (160, 240, or 340 ms) after vocal onset. Results showed that in the question intonation, response magnitudes (16 cents) were significantly reduced for the 340 ms condition compared to the 160 (26 cents) or 240 (23 cents) ms conditions. No significant differences were found, however, as a function of stimulus timing in the statement intonation. These findings demonstrate that a planned change in F(0) can cause a modulation in the reflexive response to a perturbation in voice pitch feedback and that there is a critical time period during which the response mechanisms are most sensitive to the planning process. These findings suggest an approach for the study of mechanisms involved in the timing of successive words during speech.

Hemisphere lateralization underlying auditory feedback control of voice F0.

Reflexive compensation for unexpected pitch changes in auditory feedback for stabilization of voice fundamental frequency (F0) has been demonstrated using the frequency perturbation technique. However, neural mechanisms of the pitch‐shift reflex are still unclear. This study investigated hemisphere lateralization in the auditory processing of pitch changes by using event‐related potentials. During vocalization of sustained vowels, subject's voice pitch feedback was randomly shifted upward or downward 100, 200, or 500 cents with 200 ms duration. Simultaneously, brain activity was recorded through surface electrodes located on the scalp bilaterally referenced to linked earlobes. The results showed larger brain potentials (peak difference between P200 and N100) in the C3 (left) than in the C4 (right) site, indicating left hemisphere dominance in the central motor area, while right hemisphere dominance was found in the lateral frontal area with larger potentials in the F8 (right) than in the F7 (left) site. Furthermore, these patterns were maintained regardless of stimulus magnitude and stimulus direction. This preliminary study suggests that, although both left and right hemispheres are involved in voice production, functional lateralization of the brain may exist for voice F0 control. Results also suggest that lateralization varies along the anterior‐posterior dimension of the neural axis.