Detect Pitch Changes Research Articles

Development of music-specific pitch processing

Both music and speech contain meaningful variations in pitch, however discrete pitch intervals are more prominent in music than they are in speech. Most research has separately examined perception of pitch patterning in the musical and linguistic domains; however, less is known about how listeners flexibly recruit musical and linguistic knowledge to interpret similar pitch patterns across different contexts, nor how these abilities develop with age. We asked children and adults to detect pitch changes to vocal stimuli that were presented in separate blocks as music (part of a “musical”) or speech (part of a “play”). Stimuli were overtly sung (in the musical) or spoken (in the play) but matched in pitch range and contour, and across both contexts we occasionally presented ambiguous vocalizations (speech-to-song illusions). Pitch changes were created by subjecting stimuli to a pitch range expansion which preserved the pitch contour but distorted pitch interval relationships. Adults showed greater detection accuracy for overtly sung than spoken utterances; however, children showed comparable performance for speech and song. No difference was observed for ambiguous vocalizations at any age. Implications for the development of domain-specificity of pitch processing will be discussed.

Boosting pitch encoding with audiovisual interactions in congenital amusia

The combination of information across senses can enhance perception, as revealed for example by decreased reaction times or improved stimulus detection. Interestingly, these facilitatory effects have been shown to be maximal when responses to unisensory modalities are weak. The present study investigated whether audiovisual facilitation can be observed in congenital amusia, a music-specific disorder primarily ascribed to impairments of pitch processing. Amusic individuals and their matched controls performed two tasks. In Task 1, they were required to detect auditory, visual, or audiovisual stimuli as rapidly as possible. In Task 2, they were required to detect as accurately and as rapidly as possible a pitch change within an otherwise monotonic 5-tone sequence that was presented either only auditorily (A condition), or simultaneously with a temporally congruent, but otherwise uninformative visual stimulus (AV condition). Results of Task 1 showed that amusics exhibit typical auditory and visual detection, and typical audiovisual integration capacities: both amusics and controls exhibited shorter response times for audiovisual stimuli than for either auditory stimuli or visual stimuli. Results of Task 2 revealed that both groups benefited from simultaneous uninformative visual stimuli to detect pitch changes: accuracy was higher and response times shorter in the AV condition than in the A condition. The audiovisual improvements of response times were observed for different pitch interval sizes depending on the group. These results suggest that both typical listeners and amusic individuals can benefit from multisensory integration to improve their pitch processing abilities and that this benefit varies as a function of task difficulty. These findings constitute the first step towards the perspective to exploit multisensory paradigms to reduce pitch-related deficits in congenital amusia, notably by suggesting that audiovisual paradigms are effective in an appropriate range of unimodal performance.

Left-hemisphere activation is associated with enhanced vocal pitch error detection in musicians with absolute pitch

The ability to process auditory feedback for vocal pitch control is crucial during speaking and singing. Previous studies have suggested that musicians with absolute pitch (AP) develop specialized left-hemisphere mechanisms for pitch processing. The present study adopted an auditory feedback pitch perturbation paradigm combined with ERP recordings to test the hypothesis whether the neural mechanisms of the left-hemisphere enhance vocal pitch error detection and control in AP musicians compared with relative pitch (RP) musicians and non-musicians (NM). Results showed a stronger N1 response to pitch-shifted voice feedback in the right-hemisphere for both AP and RP musicians compared with the NM group. However, the left-hemisphere P2 component activation was greater in AP and RP musicians compared with NMs and also for the AP compared with RP musicians. The NM group was slower in generating compensatory vocal reactions to feedback pitch perturbation compared with musicians, and they failed to re-adjust their vocal pitch after the feedback perturbation was removed. These findings suggest that in the earlier stages of cortical neural processing, the right hemisphere is more active in musicians for detecting pitch changes in voice feedback. In the later stages, the left-hemisphere is more active during the processing of auditory feedback for vocal motor control and seems to involve specialized mechanisms that facilitate pitch processing in the AP compared with RP musicians. These findings indicate that the left hemisphere mechanisms of AP ability are associated with improved auditory feedback pitch processing during vocal pitch control in tasks such as speaking or singing.

Prediction, attention, and unconscious processing in hierarchical auditory perception

Prediction, attention, and unconscious processing in hierarchical auditory perception

Seeing with Sound? Exploring Different Characteristics of a Visual-to-Auditory Sensory Substitution Device

Sensory substitution devices convert live visual images into auditory signals, for example with a web camera (to record the images), a computer (to perform the conversion) and headphones (to listen to the sounds). In a series of three experiments, the performance of one such device ('The vOICe') was assessed under various conditions on blindfolded sighted participants. The main task that we used involved identifying and locating objects placed on a table by holding a webcam (like a flashlight) or wearing it on the head (like a miner's light). Identifying objects on a table was easier with a hand-held device, but locating the objects was easier with a head-mounted device. Brightness converted into loudness was less effective than the reverse contrast (dark being loud), suggesting that performance under these conditions (natural indoor lighting, novice users) is related more to the properties of the auditory signal (ie the amount of noise in it) than the cross-modal association between loudness and brightness. Individual differences in musical memory (detecting pitch changes in two sequences of notes) was related to the time taken to identify or recognise objects, but individual differences in self-reported vividness of visual imagery did not reliably predict performance across the experiments. In general, the results suggest that the auditory characteristics of the device may be more important for initial learning than visual associations.

Cortical encoding of pitch: Recent results and open questions

It is widely appreciated that the key predictor of the pitch of a sound is its periodicity. Neural structures which support pitch perception must therefore be able to reflect the repetition rate of a sound, but this alone is not sufficient. Since pitch is a psychoacoustic property, a putative cortical code for pitch must also be able to account for the relationship between the amount to which a sound is periodic (i.e. its temporal regularity) and the perceived pitch salience, as well as limits in our ability to detect pitch changes or to discriminate rising from falling pitch. Pitch codes must also be robust in the presence of nuisance variables such as loudness or timbre. Here, we review a large body of work on the cortical basis of pitch perception, which illustrates that the distribution of cortical processes that give rise to pitch perception is likely to depend on both the acoustical features and functional relevance of a sound. While previous studies have greatly advanced our understanding, we highlight several open questions regarding the neural basis of pitch perception. These questions can begin to be addressed through a cooperation of investigative efforts across species and experimental techniques, and, critically, by examining the responses of single neurons in behaving animals.

Song Recognition by Children and Adolescents With Cochlear Implants

To assess song recognition and pitch perception in prelingually deaf individuals with cochlear implants (CIs). Fifteen hearing children (5-8 years) and 15 adults heard different versions of familiar popular songs-original (vocal + instrumental), original instrumental, and synthesized melody versions-and identified the song in a closed-set task (Experiment 1). Ten CI users (8-18 years) and age-matched hearing listeners performed the same task (Experiment 2). Ten CI users (8-19 years) and 10 hearing 8-years-olds were required to detect pitch changes in repeating-tone contexts (Experiment 3). Finally, 8 CI users (6-19 years) and 13 hearing 5-year-olds were required to detect subtle pitch changes in a more challenging melodic context (Experiment 4). CI users performed more poorly than hearing listeners in all conditions. They succeeded in identifying the original and instrumental versions of familiar recorded songs, and they evaluated them favorably, but they could not identify the melody versions. Although CI users could detect a 0.5-semitone change in the simple context, they failed to detect a 1-semitone change in the more difficult melodic context. Current implant processors provide insufficient spectral detail for some aspects of music perception, but they do not preclude young implant users' enjoyment of music.

Musical training and language‐related brain electrical activity in children

This experiment aimed at testing whether 8 weeks of musical training affect the ability of 8-year-old children to detect pitch changes in language. Twenty nonmusician children listened to linguistic phrases that ended with prosodically congruous words or with weak or strong pitch incongruities. We recorded reaction times, error rates, and event-related brain potentials to the final words. Half of the children followed music training and the other half painting training, and all children were retested following training. For both groups, the weak incongruity was the most difficult to detect, but performance was not significantly different between groups. However, the amplitude of a late positive component was largest to strong incongruities and was reduced after training only in the music group. These results suggest that a relatively short exposure to pitch processing in music exerts some influence on pitch processing in language.

Musically tone-deaf individuals have difficulty discriminating intonation contours extracted from speech

Musically tone-deaf individuals have psychophysical deficits in detecting pitch changes, yet their discrimination of intonation contours in speech appears to be normal. One hypothesis for this dissociation is that intonation contours use coarse pitch contrasts which exceed the pitch-change detection thresholds of tone-deaf individuals ( Peretz & Hyde, 2003). We test this idea by presenting intonation contours for discrimination, both in the context of the original sentences in which they occur and in a “pure” form dissociated from any phonetic context. The pure form consists of gliding-pitch analogs of the original intonation contours which exactly follow their pattern of pitch and timing. If the spared intonation perception of tone-deaf individuals is due to the coarse pitch contrasts of intonation, then such individuals should discriminate the original sentences and the gliding-pitch analogs equally well. In contrast, we find that discrimination of the gliding-pitch analogs is severely degraded. Thus it appears that the dissociation between spoken and musical pitch perception in tone-deaf individuals is due to a deficit at a higher level than simple pitch-change detection.

Top-down effects can modify the initially stimulus-driven auditory organization

We recorded event-related potentials (ERPs) and magnetic fields (ERFs) of the human brain to determine whether top-down control could modulate the initial organization of sound representations in the auditory cortex. We presented identical sound stimulation and manipulated top-down processes by instructing participants to either ignore the sounds (Ignore condition), to detect pitch changes (Attend-pitch condition), or to detect violations of a repeating tone pattern (Attend-pattern condition). The ERP results obtained in the Attend-pattern condition dramatically differed from those obtained with the other two task instructions. The magnetoencephalogram (MEG) findings were fully compatible, showing that the neural populations involved in detecting pattern violations differed from those involved in detecting pitch changes. The results demonstrate a top-down effect on the sound representation maintained in auditory cortex.

Congenital Amusia: A Disorder of Fine-Grained Pitch Discrimination

We report the first documented case of congenital amusia. This disorder refers to a musical disability that cannot be explained by prior brain lesion, hearing loss, cognitive deficits, socioaffective disturbance, or lack of environmental stimulation. This musical impairment is diagnosed in a middle-aged woman, hereafter referred to as Monica, who lacks most basic musical abilities, including melodic discrimination and recognition, despite normal audiometry and above-average intellectual, memory, and language skills. The results of psychophysical tests show that Monica has severe difficulties with detecting pitch changes. The data suggest that music-processing difficulties may result from problems in fine-grained discrimination of pitch, much in the same way as many language-processing difficulties arise from deficiencies in auditory temporal resolution.