Music Perception in Bone-Anchored Hearing Implant Users.

OBJECTIVE: Music is a highly complex acoustic stimulus in both spectral and temporal contents. Accurate representation and delivery of high-fidelity information are essential for music perception. However, it is unclear how well bone-anchored hearing implants (BAHIs) transmit music. The study objective is to establish music perception performance baselines for BAHI users and normal hearing (NH) listeners and compare outcomes between the cohorts. METHODS: A case-controlled, cross-sectional study was conducted among 18 BAHI users and 11 NH controls. Music perception was assessed via performance on seven major musical element tasks: pitch discrimination, melodic contour identification, rhythmic clocking, basic tempo discrimination, timbre identification, polyphonic pitch detection, and harmonic chord discrimination. RESULTS: BAHI users performed comparably well on all music perception tasks with their device compared with the unilateral condition with their better-hearing ear. BAHI performance was not statistically significantly different from NH listeners' performance. BAHI users performed just as well, if not better than NH listeners when using their control contralateral ear; there was no significant difference between the two groups except for the rhythmic timing (BAHI non-implanted ear 69% [95% CI: 62%-75%], NH 56% [95% CI: 49%-63%], p = 0.02), and basic tempo tasks (BAHI non-implanted ear 80% [95% CI: 65%-95%]; NH 75% [95% CI: 68%-82%, p = 0.03]). CONCLUSIONS: This study represents the first comprehensive study of basic music perception performance in BAHI users. Our results demonstrate that BAHI users perform as well with their implanted ear as with their contralateral better-hearing ear and NH controls in the major elements of music perception. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:1381-1387, 2024.

The Impact of Vocal Boost Manipulations on Musical Sound Quality for Cochlear Implant Users.

OBJECTIVE: To evaluate the impact of vocal boost manipulations on cochlear implant (CI) musical sound quality appraisals. METHODS: An anonymous, online study was distributed to 33 CI users. Participants listened to auditory tokens and assessed the musical quality of acoustic stimuli with vocal boosting and attenuation using a validated sound quality rating scale. Four versions of real-world musical stimuli were created: a version with +9 dB vocal boost, a version with -9 dB vocal attenuation, a composite stimulus containing a 1,000 Hz low-pass filter and white noise ("anchor"), and an unaltered version ("hidden reference"). Subjects listened to all four versions and provided ratings based on a 100-point scale that reflected the perceived sound quality difference of the music clip relative to the reference excerpt. RESULTS: Vocal boost increased musical sound quality ratings relative to the reference clip (11.7; 95% CI, 1.62-21.8, p = 0.016) and vocal attenuation decreased musical sound quality ratings relative to the reference clip (28.5; 95% CI, 18.64-38.44, p < 0.001). When comparing the non-musical training group and musical training group, there was a significant difference in musical sound quality rating scores for the vocal boost condition (21.2; 95% CI: 1.76-40.7, p = 0.028). CONCLUSIONS: CI-mediated musical sound quality appraisals are impacted by vocal boost and attenuation. Musically trained CI users to report greater musical sound quality enhancement with a vocal boost with respect to CI users with no musical training background. Implementation of front-end vocal boost manipulations in music may improve sound quality and music appreciation among CI users. LEVEL OF EVIDENCE: 2 (Individual cohort study) Laryngoscope, 133:938-947, 2023.

Effect of Frequency Response Manipulations on Musical Sound Quality for Cochlear Implant Users.

Cochlear implant (CI) users commonly report degraded musical sound quality. To improve CI-mediated music perception and enjoyment, we must understand factors that affect sound quality. In the present study, we utilize frequency response manipulation (FRM), a process that adjusts the energies of frequency bands within an audio signal, to determine its impact on CI-user sound quality assessments of musical stimuli. Thirty-three adult CI users completed an online study and listened to FRM-altered clips derived from the top songs in Billboard magazine. Participants assessed sound quality using the MUltiple Stimulus with Hidden Reference and Anchor for CI users (CI-MUSHRA) rating scale. FRM affected sound quality ratings (SQR). Specifically, increasing the gain for low and mid-range frequencies led to higher quality ratings than reducing them. In contrast, manipulating the gain for high frequencies (those above 2 kHz) had no impact. Participants with musical training were more sensitive to FRM than non-musically trained participants and demonstrated preference for gain increases over reductions. These findings suggest that, even among CI users, past musical training provides listeners with subtleties in musical appraisal, even though their hearing is now mediated electrically and bears little resemblance to their musical experience prior to implantation. Increased gain below 2 kHz may lead to higher sound quality than for equivalent reductions, perhaps because it offers greater access to lyrics in songs or because it provides more salient beat sensations.

Cochlear Implant Compression Optimization for Musical Sound Quality in MED-EL Users.

OBJECTIVES: Variations in loudness are a fundamental component of the music listening experience. Cochlear implant (CI) processing, including amplitude compression, and a degraded auditory system may further degrade these loudness cues and decrease the enjoyment of music listening. This study aimed to identify optimal CI sound processor compression settings to improve music sound quality for CI users. DESIGN: Fourteen adult MED-EL CI recipients participated (Experiment No. 1: n = 17 ears; Experiment No. 2: n = 11 ears) in the study. A software application using a modified comparison category rating (CCR) test method allowed participants to compare and rate the sound quality of various CI compression settings while listening to 25 real-world music clips. The two compression settings studied were (1) Maplaw, which informs audibility and compression of soft level sounds, and (2) automatic gain control (AGC), which applies compression to loud sounds. For each experiment, one compression setting (Maplaw or AGC) was held at the default, while the other was varied according to the values available in the clinical CI programming software. Experiment No. 1 compared Maplaw settings of 500, 1000 (default), and 2000. Experiment No. 2 compared AGC settings of 2.5:1, 3:1 (default), and 3.5:1. RESULTS: In Experiment No. 1, the group preferred a higher Maplaw setting of 2000 over the default Maplaw setting of 1000 (p = 0.003) for music listening. There was no significant difference in music sound quality between the Maplaw setting of 500 and the default setting (p = 0.278). In Experiment No. 2, a main effect of AGC setting was found; however, no significant difference in sound quality ratings for pairwise comparisons were found between the experimental settings and the default setting (2.5:1 versus 3:1 at p = 0.546; 3.5:1 versus 3:1 at p = 0.059). CONCLUSIONS: CI users reported improvements in music sound quality with higher than default Maplaw or AGC settings. Thus, participants preferred slightly higher compression for music listening, with results having clinical implications for improving music perception in CI users.

Computed Tomography-Based Measurements of the Cochlear Duct: Implications for Cochlear Implant Pitch Tuning.

OBJECTIVES: To determine the sources of variability for cochlear duct length (CDL) measurements for the purposes of fine-tuning cochlear implants (CI) and to propose a set of standardized landmarks for computed tomography (CT) pitch mapping. DESIGN: This was a retrospective cohort study involving 21 CI users at a tertiary referral center. The intervention involved flat-panel CT image acquisition and secondary reconstructions of CIs in vivo. The main outcome measures were CDL measurements, CI electrode localization measurements, and frequency calculations. RESULTS: Direct CT-based measurements of CI and intracochlear landmarks are methodologically valid, with a percentage of error of 1.0% ± 0.9%. Round window (RW) position markers (anterior edge, center, or posterior edge) and bony canal wall localization markers (medial edge, duct center, or lateral edge) significantly impact CDL calculations [F(2, 78) = 9.9, p < 0.001 and F(2, 78) = 1806, p < 0.001, respectively]. These pitch distortions could be as large as 11 semitones. When using predefined anatomical landmarks, there was still a difference between researchers [F(2, 78) = 12.5; p < 0.001], but the average variability of electrode location was reduced to differences of 1.6 semitones (from 11 semitones. CONCLUSIONS: A lack of standardization regarding RW and bony canal wall landmarks results in great CDL measurement variability and distorted pitch map calculations. We propose using the posterior edge of the RW and lateral bony wall as standardized anatomical parameters for CDL calculations in CI users to improve pitch map calculations. More accurate and precise pitch maps may improve CI-associated pitch outcomes.

Impact of Auditory-Motor Musical Training on Melodic Pattern Recognition in Cochlear Implant Users.

OBJECTIVE: Cochlear implant (CI) users struggle with tasks of pitch-based prosody perception. Pitch pattern recognition is vital for both music comprehension and understanding the prosody of speech, which signals emotion and intent. Research in normal-hearing individuals shows that auditory-motor training, in which participants produce the auditory pattern they are learning, is more effective than passive auditory training. We investigated whether auditory-motor training of CI users improves complex sound perception, such as vocal emotion recognition and pitch pattern recognition, compared with purely auditory training. STUDY DESIGN: Prospective cohort study. SETTING: Tertiary academic center. PATIENTS: Fifteen postlingually deafened adults with CIs. INTERVENTION(S): Participants were divided into 3 one-month training groups: auditory-motor (intervention), auditory-only (active control), and no training (control). Auditory-motor training was conducted with the "Contours" software program and auditory-only training was completed with the "AngelSound" software program. MAIN OUTCOME MEASURE: Pre and posttest examinations included tests of speech perception (consonant-nucleus-consonant, hearing-in-noise test sentence recognition), speech prosody perception, pitch discrimination, and melodic contour identification. RESULTS: Participants in the auditory-motor training group performed better than those in the auditory-only and no-training (p < 0.05) for the melodic contour identification task. No significant training effect was noted on tasks of speech perception, speech prosody perception, or pitch discrimination. CONCLUSIONS: These data suggest that short-term auditory-motor music training of CI users impacts pitch pattern recognition. This study offers approaches for enriching the world of complex sound in the CI user.

Perception of Child-Directed Versus Adult-Directed Emotional Speech in Pediatric Cochlear Implant Users.

OBJECTIVES: Cochlear implants (CIs) are remarkable in allowing individuals with severe to profound hearing loss to perceive speech. Despite these gains in speech understanding, however, CI users often struggle to perceive elements such as vocal emotion and prosody, as CIs are unable to transmit the spectro-temporal detail needed to decode affective cues. This issue becomes particularly important for children with CIs, but little is known about their emotional development. In a previous study, pediatric CI users showed deficits in voice emotion recognition with child-directed stimuli featuring exaggerated prosody. However, the large intersubject variability and differential developmental trajectory known in this population incited us to question the extent to which exaggerated prosody would facilitate performance in this task. Thus, the authors revisited the question with both adult-directed and child-directed stimuli. DESIGN: Vocal emotion recognition was measured using both child-directed (CDS) and adult-directed (ADS) speech conditions. Pediatric CI users, aged 7-19 years old, with no cognitive or visual impairments and who communicated through oral communication with English as the primary language participated in the experiment (n = 27). Stimuli comprised 12 sentences selected from the HINT database. The sentences were spoken by male and female talkers in a CDS or ADS manner, in each of the five target emotions (happy, sad, neutral, scared, and angry). The chosen sentences were semantically emotion-neutral. Percent correct emotion recognition scores were analyzed for each participant in each condition (CDS vs. ADS). Children also completed cognitive tests of nonverbal IQ and receptive vocabulary, while parents completed questionnaires of CI and hearing history. It was predicted that the reduced prosodic variations found in the ADS condition would result in lower vocal emotion recognition scores compared with the CDS condition. Moreover, it was hypothesized that cognitive factors, perceptual sensitivity to complex pitch changes, and elements of each child's hearing history may serve as predictors of performance on vocal emotion recognition. RESULTS: Consistent with our hypothesis, pediatric CI users scored higher on CDS compared with ADS speech stimuli, suggesting that speaking with an exaggerated prosody-akin to "motherese"-may be a viable way to convey emotional content. Significant talker effects were also observed in that higher scores were found for the female talker for both conditions. Multiple regression analysis showed that nonverbal IQ was a significant predictor of CDS emotion recognition scores while Years using CI was a significant predictor of ADS scores. Confusion matrix analyses revealed a dependence of results on specific emotions; for the CDS condition's female talker, participants had high sensitivity (d' scores) to happy and low sensitivity to the neutral sentences while for the ADS condition, low sensitivity was found for the scared sentences. CONCLUSIONS: In general, participants had higher vocal emotion recognition to the CDS condition which also had more variability in pitch and intensity and thus more exaggerated prosody, in comparison to the ADS condition. Results suggest that pediatric CI users struggle with vocal emotion perception in general, particularly to adult-directed speech. The authors believe these results have broad implications for understanding how CI users perceive emotions both from an auditory communication standpoint and a socio-developmental perspective.

Classical creativity: A functional magnetic resonance imaging (fMRI) investigation of pianist and improviser Gabriela Montero.

Improvisation is sometimes described as instant composition and offers a glimpse into real-time musical creativity. Over the last decade, researchers have built up our understanding of the core neural activity patterns associated with musical improvisation by investigating cohorts of professional musicians. However, since creative behavior calls on the unique individuality of an artist, averaging data across musicians may dilute important aspects of the creative process. By performing case study investigations of world-class artists, we may gain insight into their unique creative abilities and achieve a deeper understanding of the biological basis of musical creativity. In this experiment, functional magnetic resonance imaging and functional connectivity were used to study the neural correlates of improvisation in famed Classical music performer and improviser, Gabriela Montero. GM completed two control tasks of varying musical complexity; for the Scale condition she repeatedly played a chromatic scale and for the Memory condition she performed a given composition by memory. For the experimental improvisation condition, she performed improvisations. Thus, we were able to compare the neural activity that underlies a generative musical task like improvisation to 'rote' musical tasks of playing pre-learned and pre-memorized music. In GM, improvisation was largely associated with activation of auditory, frontal/cognitive, motor, parietal, occipital, and limbic areas, suggesting that improvisation is a multimodal activity for her. Functional connectivity analysis suggests that the visual network, default mode network, and subcortical networks are involved in improvisation as well. While these findings should not be generalized to other samples or populations, results here shed insight into the brain activity that underlies GM's unique abilities to perform Classical-style musical improvisations.

Effect of Compression on Musical Sound Quality in Cochlear Implant Users.

OBJECTIVES: Cochlear implant (CI) users frequently report poor sound quality while listening to music, although the specific parameters responsible for this loss of sound quality remain poorly understood. Audio compression, which reduces the dynamic range (DR) for a given sound, is a ubiquitous component of signal processing used by both CI and hearing aid technology. However, the relative impact of compression for acoustic and electric hearing on music perception has not been well studied, an important consideration especially given that most compression algorithms in CIs were developed to optimize speech perception. The authors hypothesized that normal-hearing (NH) listeners would detect increased levels of compression more easily than CI users, but that both groups would perceive a loss of sound quality with increasing compression levels. DESIGN: The present study utilizes the Cochlear Implant-MUltiple Stimulus with Hidden Reference and Anchor to evaluate the listener sensitivity to increasing levels of compression applied to music stimuli. The Cochlear Implant-MUltiple Stimulus with Hidden Reference and Anchor is a tool used to assess relative changes in the perceived sound quality of music across increasingly degraded listening conditions, in both CI and NH subjects. In this study, the authors applied multiple iterations of an aggressive compression algorithm to the music clips using Adobe Audition. The test conditions included 1, 3, 5, and 20 iterations sound tokens, with the 20-iteration samples serving as the Anchor stimuli. The compressed excerpts were 5 sec in length, with five clips for each of the five common musical genres (i.e., Classical, Jazz, Country, Rock, and Hip-Hop). Subjects were also presented with a Reference excerpt, which was the original music clip without any additional compression applied. CI recipients (n = 7, 11 ears) and NH listeners (n = 10) were asked to rate the sound quality of additionally compressed music as compared to the Reference. RESULTS: Although both NH and CI groups could detect sound quality differences as a function of compression level, the discriminatory ability of the CI group was blunted compared to the NH group. The CI group had less variability in their responses and overall demonstrated reduced sensitivity to deterioration caused by excessive levels of compression. On average, the CI group rated the Anchor condition as only "Slightly worse" than the Reference. The music clips that were most affected by the compression were from Jazz and Hip-Hop genres and less so for Rock and Country clips. Corollary to this was a small but statistically significant impact of DR of the music clips on sound quality ratings, with narrower DR showing an association with poorer ratings. CONCLUSIONS: These results indicate that CI users exhibit less sensitivity to sound quality changes in music attributable to high levels of compression. These findings may account for another contributing factor to the generally poor music perception observed in CI users, particularly when listening to commercially recorded music.

A Randomized Controlled Crossover Study of the Impact of Online Music Training on Pitch and Timbre Perception in Cochlear Implant Users.

Cochlear implant (CI) biomechanical constraints result in impoverished spectral cues and poor frequency resolution, making it difficult for users to perceive pitch and timbre. There is emerging evidence that music training may improve CI-mediated music perception; however, much of the existing studies involve time-intensive and less readily accessible in-person music training paradigms, without rigorous experimental control paradigms. Online resources for auditory rehabilitation remain an untapped potential resource for CI users. Furthermore, establishing immediate value from an acute music training program may encourage CI users to adhere to post-implantation rehabilitation exercises. In this study, we evaluated the impact of an acute online music training program on pitch discrimination and timbre identification. Via a randomized controlled crossover study design, 20 CI users and 21 normal hearing (NH) adults were assigned to one of two arms. Arm-A underwent 1 month of online self-paced music training (intervention) followed by 1 month of audiobook listening (control). Arm-B underwent 1 month of audiobook listening followed by 1 month of music training. Pitch and timbre sensitivity scores were taken across three visits: (1) baseline, (2) after 1 month of intervention, and (3) after 1 month of control. We found that performance improved in pitch discrimination among CI users and NH listeners, with both online music training and audiobook listening. Music training, however, provided slightly greater benefit for instrument identification than audiobook listening. For both tasks, this improvement appears to be related to both fast stimulus learning as well as procedural learning. In conclusion, auditory training (with either acute participation in an online music training program or audiobook listening) may improve performance on untrained tasks of pitch discrimination and timbre identification. These findings demonstrate a potential role for music training in perceptual auditory appraisal of complex stimuli. Furthermore, this study highlights the importance and the need for more tightly controlled training studies in order to accurately evaluate the impact of rehabilitation training protocols on auditory processing.

Automated Smartphone Audiometry: A Preliminary Validation of a Bone-Conduction Threshold Test App.

OBJECTIVE: To develop and validate an automated smartphone app that determines bone-conduction pure-tone thresholds. METHODS: A novel app, called EarBone, was developed as an automated test to determine best-cochlea pure-tone bone-conduction thresholds using a smartphone driving a professional-grade bone oscillator. Adult, English-speaking patients who were undergoing audiometric assessment by audiologists at an academic health system as part of their prescribed care were invited to use the EarBone app. Best-ear bone-conduction thresholds determined by the app and the gold standard audiologist were compared. RESULTS: Forty subjects with varied hearing thresholds were tested. Sixty-one percent of app-determined thresholds were within 5 dB of audiologist-determined thresholds, and 79% were within 10 dB. Nearly all subjects required assistance with placing the bone oscillator on their mastoid. CONCLUSION: Best-cochlea bone-conduction thresholds determined by the EarBone automated smartphone audiometry app approximate those determined by an audiologist. This serves as a proof of concept for automated smartphone-based bone-conduction threshold testing. Further improvements, such as the addition of contralateral ear masking, are needed to make the app clinically useful.

Effects of Phantom Electrode Stimulation on Vocal Production in Cochlear Implant Users.

OBJECTIVES: Cochlear implant (CI) users suffer from a range of speech impairments, such as stuttering and vocal control of pitch and intensity. Though little research has focused on the role of auditory feedback in the speech of CI users, these speech impairments could be due in part to limited access to low-frequency cues inherent in CI-mediated listening. Phantom electrode stimulation (PES) represents a novel application of current steering that extends access to low frequencies for CI recipients. It is important to note that PES transmits frequencies below 300 Hz, whereas Baseline does not. The objective of this study was to explore the effects of PES on multiple frequency-related characteristics of voice production. DESIGN: Eight postlingually deafened, adult Advanced Bionics CI users underwent a series of vocal production tests including Tone Repetition, Vowel Sound Production, Passage Reading, and Picture Description. Participants completed all of these tests twice: once with PES and once using their program used for everyday listening (Baseline). An additional test, Automatic Modulation, was included to measure acute effects of PES and was completed only once. This test involved switching between PES and Baseline at specific time intervals in real time as participants read a series of short sentences. Finally, a subjective Vocal Effort measurement was also included. RESULTS: In Tone Repetition, the fundamental frequencies (F0) of tones produced using PES and the size of musical intervals produced using PES were significantly more accurate (closer to the target) compared with Baseline in specific gender, target tone range, and target tone type testing conditions. In the Vowel Sound Production task, vowel formant profiles produced using PES were closer to that of the general population compared with those produced using Baseline. The Passage Reading and Picture Description task results suggest that PES reduces measures of pitch variability (F0 standard deviation and range) in natural speech production. No significant results were found in comparisons of PES and Baseline in the Automatic Modulation task nor in the Vocal Effort task. CONCLUSIONS: The findings of this study suggest that usage of PES increases accuracy of pitch matching in repeated sung tones and frequency intervals, possibly due to more accurate F0 representation. The results also suggest that PES partially normalizes the vowel formant profiles of select vowel sounds. PES seems to decrease pitch variability of natural speech and appears to have limited acute effects on natural speech production, though this finding may be due in part to paradigm limitations. On average, subjective ratings of vocal effort were unaffected by the usage of PES versus Baseline.

Association Between Flat-Panel Computed Tomographic Imaging-Guided Place-Pitch Mapping and Speech and Pitch Perception in Cochlear Implant Users.

Importance: Cochlear implant users generally display poor pitch perception. Flat-panel computed tomography (FPCT) has recently emerged as a modality capable of localizing individual electrode contacts within the cochlea in vivo. Significant place-pitch mismatch between the clinical implant processing settings given to patients and the theoretical maps based on FPCT imaging has previously been noted. Objective: To assess whether place-pitch mismatch is associated with poor cochlear implant-mediated pitch perception through evaluation of an individualized, image-guided approach toward cochlear implant programming on speech and music perception among cochlear implant users. Design, Setting, and Participants: A prospective cohort study of 17 cochlear implant users with MED-EL electrode arrays was performed at a tertiary referral center. The study was conducted from June 2016 to July 2017. Interventions: Theoretical place-pitch maps using FPCT secondary reconstructions and 3-dimensional curved planar re-formation software were developed. The clinical map settings (eg, strategy, rate, volume, frequency band range) were modified to keep factors constant between the 2 maps and minimize confounding. The acclimation period to the maps was 30 minutes. Main Outcomes and Measures: Participants performed speech perception tasks (eg, consonant-nucleus-consonant, Bamford-Kowal-Bench Speech-in-Noise, vowel identification) and a pitch-scaling task while using the image-guided place-pitch map (intervention) and the modified clinical map (control). Performance scores between the 2 interventions were measured. Results: Of the 17 participants, 10 (58.8%) were women; mean (SD) was 59 (11.3) years. A significant median increase in pitch scaling accuracy was noted when using the experimental map compared with the control map (4 more correct answers; 95% CI, 0-8). Specifically, the number of pitch-scaling reversals for notes spaced at 1.65 semitones or greater decreased when an image-based approach to cochlear implant programming was used vs the modified clinical map (4 mistakes; 95% CI, 0.5-7). Although there was no observable median improvement in speech perception during use of an image-based map, the acute changes in frequency allocation and electrode channel deactivations used with the image-guided maps did not worsen consonant-nucleus-consonant (-1% correct phonemes, 95% CI, -2.5% to 6%) and Bamford-Kowal-Bench Speech-in-Noise (0.5-dB difference; 95% CI, -0.75 to 2.25 dB) median performance results relative to the clinical maps used by the patients. Conclusions and Relevance: An image-based approach toward ochlear implant mapping may improve pitch perception outcomes by reducing place-pitch mismatch. Studies using a longer acclimation period with chronic stimulation over months may help assess the full range of the benefits associated with personalized image-guided cochlear implant mapping.

Tripolar Stimulation Improves Polyphonic Pitch Detection in Cochlear Implant Users.

OBJECTIVE: Cochlear implant (CI) users struggle with pitch perception, particularly for polyphonic stimuli. Tripolar (TP) stimulation has been proposed as a way to mitigate the broad spread of neural excitation observed in traditional monopolar (MP) stimulation, thereby potentially improving perception of polyphony. STUDY DESIGN: Prospective cohort study. SETTING: Tertiary academic center. PATIENTS: Eleven postlingually deafened adults with Advanced Bionics HiRes 90K CIs. INTERVENTION(S): We performed pitch ranking and polyphonic pitch detection testing under MP and TP configurations. To assess pitch ranking, users were asked to identify the higher pitch between two notes. In polyphonic pitch detection, users were asked to distinguish between single-pitch tones and two-pitch tones. Two-pitch stimuli consisted of one pitch of three base frequencies (392, 523, 740 Hz) and a second pitch between 1 and 12 semitones above the base frequency. MAIN OUTCOME MEASURE: Pitch performance was analyzed as a function of current delivery mode (tripolar vs. monopolar), with smaller semitone interval pitch resolution indicating better performance. RESULTS: In pitch ranking tasks, TP configuration did not confer an advantage over MP stimulation. In polyphonic perception, however, tripolar stimulation improved performance in lower frequencies and resulted in statistically significant (p < 0.05) improvement at the highest base frequency, 740 Hz. CONCLUSIONS: These data suggest that TP configuration may confer an advantage in the perception of polyphonic pitch, which may not be observed in monophonic pitch ranking tasks. Since music is typically polyphonic, such data offer approaches toward improving perception of real-world musical stimuli.

Automated smartphone audiometry: Validation of a word recognition test app.

OBJECTIVES/HYPOTHESIS: Develop and validate an automated smartphone word recognition test. STUDY DESIGN: Cross-sectional case-control diagnostic test comparison. METHODS: An automated word recognition test was developed as an app for a smartphone with earphones. English-speaking adults with recent audiograms and various levels of hearing loss were recruited from an audiology clinic and were administered the smartphone word recognition test. Word recognition scores determined by the smartphone app and the gold standard speech audiometry test performed by an audiologist were compared. RESULTS: Test scores for 37 ears were analyzed. Word recognition scores determined by the smartphone app and audiologist testing were in agreement, with 86% of the data points within a clinically acceptable margin of error and a linear correlation value between test scores of 0.89. CONCLUSIONS: The WordRec automated smartphone app accurately determines word recognition scores. LEVEL OF EVIDENCE: 3b. Laryngoscope, 128:707-712, 2018.

The Effect of Round Window vs Cochleostomy Surgical Approaches on Cochlear Implant Electrode Position: A Flat-Panel Computed Tomography Study.

IMPORTANCE: The round window insertion (RWI) and cochleostomy approaches are the 2 most common surgical techniques used in cochlear implantation (CI). However, there is no consensus on which approach is ideal for electrode array insertion, in part because visualization of intracochlear electrode position is challenging, so postoperative assessment of intracochlear electrode contact is lacking. OBJECTIVE: To measure and compare electrode array position between RWI and cochleostomy approaches for CI insertion. DESIGN, SETTING, AND PARTICIPANTS: Retrospective case-comparison study of 17 CI users with Med-El standard-length electrode arrays who underwent flat-panel computed tomography scans after CI surgery at a tertiary referral center. The data was analyzed in October 2015. EXPOSURES: Flat-panel computed tomography scans were collected between January 1 and August 31, 2013, for 22 electrode arrays. The surgical technique was identified by a combination of operative notes and imaging. Eight cochleae underwent RWI and 14 cochleae underwent cochleostomy approaches anterior and inferior to the round window. MAIN OUTCOMES AND MEASURES: Interscalar electrode position and electrode centroid distance to the osseous spiral lamina, lateral bony wall, and central axis of the modiolus. RESULTS: Nine participants were men, and 8, women; the mean age was 54.4 (range, 21-64) years. Electrode position was significantly closer to cochlear neural elements with RWI than cochleostomy approaches. Between the 2 surgical approaches, the RWI technique produced shorter distances between the electrode and the modiolus (mean difference, -0.33 [95% CI, -0.29 to -0.39] mm in the apical electrode; -1.42 [95% CI, -1.24 to -1.57] mm in the basal electrode). This difference, which was most prominent in the first third and latter third of the basal turn, decreased after the basal turn. CONCLUSIONS AND RELEVANCE: The RWI approach was associated with an increased likelihood of perimodiolar placement. Opting to use RWI over cochleostomy approaches in CI candidates may position electrodes closer to cochlear neural substrates and minimize current spread. These findings need to be interpreted in light of the increased potential for osseous spiral lamina trauma with reduced distances between the electrode array and modiolus.

Mandarin Tone Identification in Cochlear Implant Users Using Exaggerated Pitch Contours.

OBJECTIVE: To determine whether exaggerating the variations in fundamental frequency (F0) contours of Mandarin-based pitch fluctuations could improve tone identification by cochlear implant (CI) users. METHODS: Twelve normal-hearing (NH) listeners and 11 CI users were tested for their ability to recognize F0 contours modeled after Mandarin tones, in 4- or 5-alternatives forced-choice paradigms. Two types of stimuli were used: computer-generated complex tones and voice recordings. Four contours were tested with voice recordings: flat, rise, fall, and dip. A fifth contour, peak, was added for complex tones. The F0 range of each contour was varied in an adaptive manner. A maximum-likelihood technique was used to fit a psychometric function to the performance data and extract threshold at 70% accuracy. RESULTS: As F0 range increased, performance in tone identification improved but did not reach 100% for some CI users, suggesting that confusions between contours could always be made even with extremely exaggerated contours. Compared with NH participants, CI users required substantially larger F0 ranges to identify tones, on the order of 9.3 versus 0.4 semitones. CI users achieved better performance for complex tones than for voice recordings, whereas the reverse was true for NH participants. Confusion matrices showed that the "flat" tone was often a default option when the tone contour's F0 range presented was too narrow for participants to respond correctly. CONCLUSION: These results demonstrate markedly impaired ability for CI users to identify tonal contours, but suggest that the use of exaggerated pitch contours may be helpful for tonal language perception.

Impaired Perception of Sensory Consonance and Dissonance in Cochlear Implant Users.

HYPOTHESIS: In light of previous research demonstrating poor pitch perception in cochlear implant (CI) users, we hypothesized that the presence of consonant versus dissonant chord accompaniment in real-world musical stimuli would not impact subjective assessment of degree of pleasantness in CI users. BACKGROUND: Consonance/dissonance are perceptual features of harmony resulting from pitch relationships between simultaneously presented musical notes. Generally, consonant sounds are perceived as pleasant and dissonant ones as unpleasant. CI users exhibit impairments in pitch perception, making music listening difficult and often unenjoyable. To our knowledge, consonance/dissonance perception has not been studied in the CI population. METHODS: Twelve novel melodies were created for this study. By altering the harmonic structures of the accompanying chords, we created three permutations of varying dissonance for each melody (36 stimuli in all). Ten CI users and 12 NH listeners provided Likert scale ratings from -5 (very unpleasant) to +5 (very pleasant) for each of the stimuli. RESULTS: A two-way ANOVA showed main effects for Dissonance Level and Subject Type as well as a two-way interaction between the two. Pairwise comparisons indicated that NH stimuli pleasantness ratings decreased with increasing dissonance, whereas CI ratings did not. NH pleasantness ratings were consistently lower than CI ratings. CONCLUSION: For CI users, consonant versus dissonant chord accompaniment had no significant impact on whether a melody was considered pleasant or unpleasant. This finding may be partially responsible for the decreased enjoyment of many CI users during music perception and is another manifestation of impaired pitch perception in CI users.

Emotional Intent Modulates The Neural Substrates Of Creativity: An fMRI Study of Emotionally Targeted Improvisation in Jazz Musicians.

Emotion is a primary motivator for creative behaviors, yet the interaction between the neural systems involved in creativity and those involved in emotion has not been studied. In the current study, we addressed this gap by using fMRI to examine piano improvisation in response to emotional cues. We showed twelve professional jazz pianists photographs of an actress representing a positive, negative or ambiguous emotion. Using a non-ferromagnetic thirty-five key keyboard, the pianists improvised music that they felt represented the emotion expressed in the photographs. Here we show that activity in prefrontal and other brain networks involved in creativity is highly modulated by emotional context. Furthermore, emotional intent directly modulated functional connectivity of limbic and paralimbic areas such as the amygdala and insula. These findings suggest that emotion and creativity are tightly linked, and that the neural mechanisms underlying creativity may depend on emotional state.

Deeper Cochlear Implant Electrode Insertion Angle Improves Detection of Musical Sound Quality Deterioration Related to Bass Frequency Removal.

BACKGROUND: Cochlear implant (CI) electrode arrays typically do not reach the most apical regions of the cochlea that intrinsically encode low frequencies. This may contribute to diminished implant-mediated musical sound quality perception. The objective of this study was to assess the effect of varying degrees of apical cochlear stimulation (measured by angular insertion depth) on musical sound quality discrimination. HYPOTHESIS: Increased apical cochlear stimulation will improve low-frequency perception and musical sound quality discrimination. METHODS: Standard (31.5 mm, n = 17) and medium (24 mm, n = 8) array Med-EL CI users, and normal hearing (NH) listeners (n = 16) participated. Imaging confirmed angular insertion depth. Participants completed a musical discrimination task in which they listened to a real-world musical stimulus (labeled reference) and provided sound quality ratings to versions of the reference, which included a hidden reference and test stimuli with increasing amounts of low-frequency removal. Scores for each CI users were calculated on the basis of how much their ratings differed from NH listeners for each stimulus version. RESULTS: Medium array and standard users had significantly different insertion depths (389.4 ± 64.5 and 583.9 ± 78.5 degrees, respectively; p <  .001). A significant Pearson's correlation was observed between angular insertion depth and the hidden reference scores (p < 0.05). CONCLUSION: CI users with greater apical stimulation made sound quality discriminations that more closely resembled those of NH controls for stimuli that contained low frequencies (< 200 Hz of information). These findings suggest that increased apical cochlear stimulation improves musical low-frequency perception, which may provide a more satisfactory music listening experience for CI users.