Childhood Listening and Associated Cognitive Difficulties Persist Into Adolescence.

OBJECTIVE: Listening difficulty (LiD) refers to the challenges individuals face when trying to hear and comprehend speech and other sounds. LiD can arise from various sources, such as hearing sensitivity, language comprehension, cognitive function, or auditory processing. Although some children with LiD have hearing loss, many have clinically normal audiometric thresholds. To determine the impact of hearing and cognitive factors on LiD in children with a clinically normal audiogram, we conducted a longitudinal study. The Evaluation of Children's Listening & Processing Skills (ECLiPS), a validated and standardized caregiver evaluation tool, was used to group participants as either LiD or typically developing (TD). Our previous study aimed to characterize LiD in 6- to 13-year-old children during the project's baseline, cross-sectional phase. We found that children with LiD needed a higher signal-to-noise ratio during speech-in-speech tests and scored lower on all assessed components of the NIH Cognition Toolbox than TD children. The primary goal of this study was to examine if the differences between LiD and TD groups are temporary or enduring throughout childhood. DESIGN: This longitudinal study had three data collection waves for children with LiD and TD aged 6 to 13 years at Wave 1, followed by assessments at 2-year (Wave 2) and 4-year (Wave 3) intervals. Primary analysis focused on data from Waves 1 and 2. Secondary analysis encompassed all three waves despite high attrition at Wave 3. Caregivers completed the ECLiPS, while participants completed the Listening in Spatialized Noise-Sentences (LiSN-S) test and the NIH-Toolbox Cognition Battery during each wave. The analysis consisted of (1) examining longitudinal differences between TD and LiD groups in demographics, listening, auditory, and cognitive function; (2) identifying functional domains contributing to LiD; and (3) test-retest reliability of measures across waves. Mixed-effect models were employed to analyze longitudinal data. RESULTS: The study enrolled 169 participants, with 147, 100, and 31 children completing the required testing during Waves 1, 2, and 3, respectively. The mean ages at these waves were 9.5, 12.0, and 14.0 years. On average, children with LiD consistently underperformed TD children in auditory and cognitive tasks across all waves. Maternal education, auditory, and cognitive abilities independently predicted caregiver-reported listening skills. Significant correlations between Waves 1 and 2 confirmed high, long-term reliability. Secondary analysis of Wave 3 was consistent with the primary analyses of Waves 1 and 2, reinforcing the enduring nature of listening difficulties. CONCLUSION: Children with LiD and clinically normal audiograms experience persistent auditory, listening, and cognitive challenges through at least adolescence. The degree of LiD can be independently predicted by maternal education, cognitive processing, and spatial listening skills. This study underscores the importance of early detection and intervention for childhood LiD and highlights the role of socioeconomic factors as contributors to these challenges.

Auditory cortex and beyond: Deficits in congenital amusia.

Congenital amusia is a neuro-developmental disorder of music perception and production, with the observed deficits contrasting with the sophisticated music processing reported for the general population. Musical deficits within amusia have been hypothesized to arise from altered pitch processing, with impairments in pitch discrimination and, notably, short-term memory. We here review research investigating its behavioral and neural correlates, in particular the impairments at encoding, retention, and recollection of pitch information, as well as how these impairments extend to the processing of pitch cues in speech and emotion. The impairments have been related to altered brain responses in a distributed fronto-temporal network, which can be observed also at rest. Neuroimaging studies revealed changes in connectivity patterns within this network and beyond, shedding light on the brain dynamics underlying auditory cognition. Interestingly, some studies revealed spared implicit pitch processing in congenital amusia, showing the power of implicit cognition in the music domain. Building on these findings, together with audiovisual integration and other beneficial mechanisms, we outline perspectives for training and rehabilitation and the future directions of this research domain.

Individuals with congenital amusia remember music they like.

Music is better recognized when it is liked. Does this association remain evident when music perception and memory are severely impaired, as in congenital amusia? We tested 11 amusic and 11 matched control participants, asking whether liking of a musical excerpt influences subsequent recognition. In an initial exposure phase, participants-unaware that their recognition would be tested subsequently-listened to 24 musical excerpts and judged how much they liked each excerpt. In the test phase that followed, participants rated whether they recognized the previously heard excerpts, which were intermixed with an equal number of foils matched for mode, tempo, and musical genre. As expected, recognition was in general impaired for amusic participants compared with control participants. For both groups, however, recognition was better for excerpts that were liked, and the liking enhancement did not differ between groups. These results contribute to a growing body of research that examines the complex interplay between emotions and cognitive processes. More specifically, they extend previous findings related to amusics' impairments to a new memory paradigm and suggest that (1) amusic individuals are sensitive to an aesthetic and subjective dimension of the music-listening experience, and (2) emotions can support memory processes even in a population with impaired music perception and memory.

The relationship between acoustic and musical pitch processing in adolescents.

Amusia is defined as a difficulty processing the tonal pitch structure of music such that an individual cannot tell the difference between notes that are in-key and out-of-key. A fine-grained pitch discrimination deficit is often observed in people with amusia. It is possible that an intervention, early in development, could mitigate amusia; however, one challenge identifying amusia early in development is that identifying in- and out-of-key notes is a metacognitive task. Given the common co-occurrence of difficulties with pitch discrimination, it would be easier to identify amusia in developing children by using a pitch change detection task. The goal of this study was to explore the behavioural and neurophysiological profiles of adolescents with poor pitch processing (Poor PP) abilities compared with those with normal pitch processing (Normal PP) abilities. Neurophysiologically, the Poor PPs exhibited a similar event-related potential (ERP) profile to adult amusics during both acoustic and musical pitch discrimination tasks. That is, early ERPs (ERAN, MMN) were similar in Poor PPs compared with Normal PPs, whereas late positivities (P300, P600) were absent in Poor PPs, but present in Normal PPs. At the same time, behavioural data revealed a double dissociation between the abilities to detect a pitch deviant in acoustic and musical context, suggesting that about a third of the children would be missed by selecting a fine-grained acoustic pitch discrimination task to identify the presence of amusia in early childhood.

The impact of vocal tuning in the perceptual auditory judgment of normal and deviated voice qualities. / O impacto da afinação vocal na análise perceptivo-auditiva de vozes normais e alteradas.

PURPOSE: To evaluate the ability that in tune and out of tune individuals have to identify normal and deviated voice qualities and to compare it with their performance in auditory processing tests and perceptual judgment. METHOD: The study investigated 15 in tune and 15 out of tune individuals. Participants were matched for age and sex, were amateur choir singers, had normal hearing thresholds and normal vocal quality. All individuals underwent Pitch-matching scanning to be classified as in or out of tune. Next, they performed the Pitch Pattern Sequence (PPS) and the Duration Pattern Sequence (DPS) tests and the perceptual judgment of 36 voices plus 20% of repetition for reliability analysis. RESULTS: The out of tune individuals had worse performance in the PPS and DPS for both ears (p=0.002 RE; p=0.001 LE; p=0.009 DPS); no difference was observed in the perceptual judgment and the reliability (p=0.153). However, participants with normal PPS and DPS had better performance in the perceptual judgment and better reliability (p=0.033). Thus, individuals with disorders in temporal auditory processing skills have greater difficulty in the perceptual judgment and have lower intra-rater reliability, despite being in or out of tune. CONCLUSION: It can be observed that voice tone is not required to guarantee good perceptual judgment. However, temporal patterns and intra-rater reliability are essential to perceptually assess normal and altered voice qualities. Therefore, auditory training should be included in programs that aim to develop voice perceptual judgment abilities.

[Congenital amusia and its effects on non-musical skills]. / Amusia congénita y sus efectos en habilidades no musicales.

INTRODUCTION: Congenital amusia is a specific condition in which the individual is unable to recognise tonal variations in a piece of musical. This cannot be explained by a previous brain injury, hearing loss, cognitive deficit, socio-affective disorder or lack of environmental stimulation. The current estimated prevalence is 1.5% of the world population, with a significant genetic component among those who suffer from it. It has been claimed that certain cognitive abilities in the emotional, spatial and language fields may be affected in people with amusia. AIM: To review the literature describing the effects on non-musical skills that may coexist in individuals with congenital amusia. DEVELOPMENT: Several neuroimaging studies have observed morphological and functional changes in the temporal lobe, as well as in the white matter connections between the superior temporal gyrus and the inferior frontal gyrus. From these affected regions, there may be a deficit in cognitive skills related to adjacent areas. CONCLUSIONS: Congenital amusia has been associated with poor performance in different non-musical cognitive skills, such as visuospatial processing, language processing, reading difficulties, face recognition and emotional aspects.

TITLE: Amusia congénita y sus efectos en habilidades no musicales.Introducción. La amusia congénita es una condición específica en la que el individuo afectado es incapaz de reconocer variaciones tonales en las piezas musicales. Esto no puede explicarse por una lesión encefálica previa, una pérdida auditiva, un déficit cognitivo, un trastorno socioafectivo o una falta de estimulación ambiental. Actualmente se estima una prevalencia del 1,5% de la población mundial, con un importante componente genético entre los afectados. Se ha descrito que en las personas con amusia puede haber afectación de ciertas habilidades cognitivas en el campo emocional, espacial y del lenguaje. Objetivo. Revisar la bibliografía donde se describen los efectos en las habilidades no musicales que pueden coexistir en individuos con amusia congénita. Desarrollo. Varios estudios de neuroimagen han permitido observar cambios morfológicos y funcionales en el lóbulo temporal, así como en las conexiones de la sustancia blanca entre el giro temporal superior y el giro frontal inferior. Partiendo de estas regiones afectadas, podría existir un déficit en habilidades cognitivas relacionadas con áreas adyacentes. Conclusiones. La amusia congénita se ha relacionado con un pobre desempeño en diferentes habilidades cognitivas no musicales, como el procesamiento visuoespacial, el procesamiento del lenguaje, alteraciones de la lectura, el reconocimiento de rostros y aspectos emocionales.

Auditory processing disorder may be present in schizophrenia and it is highly correlated with formal thought disorder.

The present study investigates the presence of Auditory Processing Disorder (APD) in schizophrenia and its association with symptomatology, especially Formal Thought Disorder (FTD). 50 patients with schizophrenia and 25 matched healthy controls completed a battery of three auditory processing tests. Positive and Negative Syndrome Scale (PANSS) and Thought, Language and Communication (TLC) scale were used to assess clinical symptoms. The patient group was divided into two subgroups, according to FTD severity. Auditory processing performance of the control group and the patient group was evaluated. Correlations between auditory processing scores and TLC scores, as well as auditory processing scores and PANSS scores were examined. Most of the patients, especially those with FTD, had auditory deficits that can be classified as APD. Patients showed impaired performance compared to controls in all tests. Total severity and specific factors of FTD, as well as other clinical symptoms and symptom categories were correlated with auditory processing performance. We provided evidence that APD may be present in schizophrenia and that FTD, as well as other clinical symptoms are associated with auditory processing deficits. There are important clinical implications for non-pharmacological interventions and early diagnosis of schizophrenia.

Multi-level evidence of an allelic hierarchy of USH2A variants in hearing, auditory processing and speech/language outcomes.

Language development builds upon a complex network of interacting subservient systems. It therefore follows that variations in, and subclinical disruptions of, these systems may have secondary effects on emergent language. In this paper, we consider the relationship between genetic variants, hearing, auditory processing and language development. We employ whole genome sequencing in a discovery family to target association and gene x environment interaction analyses in two large population cohorts; the Avon Longitudinal Study of Parents and Children (ALSPAC) and UK10K. These investigations indicate that USH2A variants are associated with altered low-frequency sound perception which, in turn, increases the risk of developmental language disorder. We further show that Ush2a heterozygote mice have low-level hearing impairments, persistent higher-order acoustic processing deficits and altered vocalizations. These findings provide new insights into the complexity of genetic mechanisms serving language development and disorders and the relationships between developmental auditory and neural systems.

Perceptual and Objective Assessment of Envelope Enhancement for Children With Auditory Processing Disorder.

This paper evaluated the performance of an envelope enhancement (EE) algorithm subjectively by children with auditory processing disorder (APD), and objectively through computational models. Speech intelligibility data was collected from children with APD, for unprocessed and envelope-enhanced speech in the presence of stationary and non-stationary background noise at different signal to noise ratios (SNRs), both with and without noise reduction (NR) algorithms as a front-end to the EE algorithm. Furthermore, intrusive and non-intrusive objective speech intelligibility metrics were derived to predict the perceptual impact of this EE algorithm. Subjective data for stationary noise conditions revealed that the combination of NR and EE algorithms significantly improved the speech intelligibility scores at poor SNRs. In contrast, the same combination was ineffective in improving speech intelligibility in non-stationary noise conditions. Taken together, subjective results suggest that exaggerating the envelope cues improves speech identification scores for children with APD. However, the benefit obtained varies depending upon the type and level of the background noise. Both intrusive and non-intrusive objective speech intelligibility estimators exhibited good correlation with the subjective data, with the intrusive metric demonstrating better generalization capabilities. Implications of these results for hearing aid applications for children with APD is discussed.

Auditory processing disorders in incarcerated youth: A call for early detection and treatment.

BACKGROUND: Numerous reports have linked language impairment, academic underachievement, and attention disorder to misbehavior in adolescence. Recent studies have found an association between deficits in hearing and auditory processing and involvement in the juvenile justice system. In fact, the existence of an auditory processing disorder (APD) is a risk factor for adolescent delinquency even in the presence of normal hearing. The nexus between APD, low academic achievement and offending behavior in teens has prompted recommendation for early screening of school children for abnormalities in auditory processing. Using a variety of diagnostic tools, investigators have found an increase in the frequency of APD in cohorts of confined youthful offenders. The present investigation evaluates the prevalence of APD in a group of incarcerated youth residing in a detention center. METHODS: A total of 52 incarcerated adolescents (8 females and 44 males; age range 13-20 (M = 16.0), residing at a juvenile detention center in Pittsburgh, Pennsylvania and determined to have normal auditory acuity were included in the study. All participants were screened for APD using two dichotic listening tests, the Randomized Dichotic Digits Test (RDDT) and the Dichotic Words Test (DWT), evaluative modalities to identify deficits in auditory processing. The prevalence of APD in the study group was compared to previously published normative data for non-offending age-matched youth. RESULTS: On the RDDT, 23.1% of participants demonstrated normal auditory processing, while 77% had abnormal test results. On the DWT, 75% of subjects exhibited normal auditory processing, while the scores were abnormal for 24.9%. When the results of the RDDT and the DWT were combined to establish a pattern for the purpose of interpreting a deficit, 21.1% of the participants produced results that were within normal limits, while 17.3% qualified for a diagnosis of APD, with abnormal results on both tests. Previous studies have estimated the prevalence of auditory processing disorder in the general adolescent population as being between 2% and 7%. CONCLUSIONS: This study found a higher prevalence of auditory processing disorder in a cohort of incarcerated youth compared with age-matched controls. Diagnostic screening protocols that identify at-risk children have been developed, as have effective therapies to improve auditory processing function. Teachers, pediatricians and psychologists should consider APD in children and adolescents with behaviors that may increase their risk for juvenile justice involvement. Studies on optimal timing and strategies for assessing and treating APD in children and adolescents are needed, including youth caught up in the juvenile justice system.

O impacto da afinação vocal na análise perceptivo-auditiva de vozes normais e alteradas / The impact of vocal tuning in the perceptual auditory judgment of normal and deviated voice qualities

RESUMO Objetivo: Avaliar a habilidade de identificação de vozes normais e alteradas por indivíduos afinados e desafinados, comparando seu desempenho nos testes de processamento auditivo e na avaliação perceptivo-auditiva. Método: Participaram 15 indivíduos afinados e 15 desafinados pareados quanto à idade e sexo, oriundos de um coral amador, com limiares auditivos e qualidade vocal dentro dos padrões de normalidade. Todos foram submetidos à Triagem da Afinação vocal para a alocação nos grupos de afinados e desafinados. Em seguida, realizaram o Teste Padrão de Frequência (TPF), Teste Padrão de Duração (TPD) e análise perceptivo-auditiva de 36 vozes, mais 20% de repetição para teste de confiabilidade. Resultados: Os indivíduos desafinados apresentaram resultados estatisticamente menores que os afinados no TPF e no TPD para ambas as orelhas (p=0,002 OD; p=0,001 OE; p=0,009 TPD). Resultados da análise perceptivo-auditiva e da confiabilidade não apresentaram diferença (p=0,153). Contudo, esses resultados foram melhores quando comparados os participantes com valores normais no TPF e TPD, em relação aos resultados alterados (p=0,033). Assim, participantes com testes temporais de processamento auditivo alterados apresentaram maiores dificuldades na análise perceptivo-auditiva e menor confiabilidade intrassujeito, independentemente de serem ou não afinados. Conclusão: Percebe-se que a afinação vocal não é um pré-requisito para a realização de uma boa avaliação perceptivo-auditiva da voz, mas os padrões temporais e a confiabilidade intrassujeito estão notavelmente associados à análise perceptivo-auditiva de vozes normais e alteradas. Assim, sugere-se que o treinamento auditivo seja contemplado em programas de desenvolvimento da habilidade de realizar avaliação perceptivo-auditiva da voz.

ABSTRACT Purpose: To evaluate the ability that in tune and out of tune individuals have to identify normal and deviated voice qualities and to compare it with their performance in auditory processing tests and perceptual judgment. Method: The study investigated 15 in tune and 15 out of tune individuals. Participants were matched for age and sex, were amateur choir singers, had normal hearing thresholds and normal vocal quality. All individuals underwent Pitch-matching scanning to be classified as in or out of tune. Next, they performed the Pitch Pattern Sequence (PPS) and the Duration Pattern Sequence (DPS) tests and the perceptual judgment of 36 voices plus 20% of repetition for reliability analysis. Results: The out of tune individuals had worse performance in the PPS and DPS for both ears (p=0.002 RE; p=0.001 LE; p=0.009 DPS); no difference was observed in the perceptual judgment and the reliability (p=0.153). However, participants with normal PPS and DPS had better performance in the perceptual judgment and better reliability (p=0.033). Thus, individuals with disorders in temporal auditory processing skills have greater difficulty in the perceptual judgment and have lower intra-rater reliability, despite being in or out of tune. Conclusion: It can be observed that voice tone is not required to guarantee good perceptual judgment. However, temporal patterns and intra-rater reliability are essential to perceptually assess normal and altered voice qualities. Therefore, auditory training should be included in programs that aim to develop voice perceptual judgment abilities.

Vowel and Tone Identification for Mandarin Congenital Amusics: Effects of Vowel Type and Semantic Content.

Purpose This study aimed to explore the effects of Mandarin congenital amusia with or without lexical tone deficit (i.e., tone agnosia and pure amusia) on Mandarin vowel and tone identification in different types of vowels (e.g., monophthong, diphthongs, and triphthongs) embedded in consonant-vowel contexts with and without semantic content. Method Thirteen pure amusics (i.e., amusics with normal lexical processing), 5 tone agnosics (i.e., with lexical tone deficit), and 12 controls were screened with Montreal Battery of Evaluation of Amusia and lexical tone tests (Nan et al., 2010; Peretz et al., 2003). Vowel-plus-tone identification tasks with the factors of vowel type and syllables with and without semantic content (e.g., real and nonsense words) were examined among the 3 groups, and identification scores were calculated in 3 formats: vowel-plus-tone identification, vowel identification, and tone identification. Results Tone agnosics showed significantly poorer performances on identifications of vowel, tone, and vowel plus tone across monophthongs, diphthongs, and triphthongs in both real and nonsense words compared to pure amusics and controls. Their deficits were similar across the 3 types of vowels, while the deficit on vowel-plus-tone identification was more severe in nonsense words than in real words. On the other hand, pure amusics performed similarly with controls across all these conditions. Conclusions Tone agnosia might affect both musical pitch and phonological processing, resulting in deficits in lexical tone and vowel perception. On the contrary, pure amusics's effect is primarily on musical pitch perception but not on lexical tone or phonemic deficit. Vowel type did not affect speech deficits for tone agnosics, while they relied more on semantic content as a compensation.

Emotional prosody in congenital amusia: Impaired and spared processes.

Congenital amusia is a lifelong deficit of music processing, in particular of pitch processing. Most research investigating this neurodevelopmental disorder has focused on music perception, but pitch also has a critical role for intentional and emotional prosody in speech. Two previous studies investigating amusics' emotional prosody recognition have shown either some deficit or no deficit (compared to controls). However, these previous studies have used only long sentence stimuli, which allow for limited control over acoustic content. Here, we tested amusic individuals for emotional prosody perception in sentences and vowels. For each type of material, participants performed an emotion categorization task, followed by intensity ratings of the recognized emotion. Compared to controls, amusic individuals had similar recognition of emotion in sentences, but poorer performance in vowels, especially when distinguishing sad and neutral stimuli. These lower performances in amusics were linked with difficulties in processing pitch and spectro-temporal parameters of the vowel stimuli. For emotion intensity, neither sentence nor vowel ratings differed between participant groups, suggesting preserved implicit processing of emotional prosody in amusia. These findings can be integrated into previous data showing preserved implicit processing of pitch and emotion in amusia alongside deficits in explicit recognition tasks. They are thus further supporting the hypothesis of impaired conscious analysis of pitch and timbre in this neurodevelopmental disorder.

Short- and long-term memory for pitch and non-pitch contours: Insights from congenital amusia.

Congenital amusia is a neurodevelopmental disorder characterized by deficits in music perception, including discriminating and remembering melodies and melodic contours. As non-amusic listeners can perceive contours in dimensions other than pitch, such as loudness and brightness, our present study investigated whether amusics' pitch contour deficits also extend to these other auditory dimensions. Amusic and control participants performed an identification task for ten familiar melodies and a short-term memory task requiring the discrimination of changes in the contour of novel four-tone melodies. For both tasks, melodic contour was defined by pitch, brightness, or loudness. Amusic participants showed some ability to extract contours in all three dimensions. For familiar melodies, amusic participants showed impairment in all conditions, perhaps reflecting the fact that the long-term memory representations of the familiar melodies were defined in pitch. In the contour discrimination task with novel melodies, amusic participants exhibited less impairment for loudness-based melodies than for pitch- or brightness-based melodies, suggesting some specificity of the deficit for spectral changes, if not for pitch alone. The results suggest pitch and brightness may not be processed by the same mechanisms as loudness, and that short-term memory for loudness contours may be spared to some degree in congenital amusia.

Impaired emotional processing of chords in congenital amusia: Electrophysiological and behavioral evidence.

This study investigated whether individuals with congenital amusia, a neurogenetic disorder of musical pitch perception, were able to process musical emotions in single chords either automatically or consciously. In Experiments 1 and 2, we used a cross-modal affective priming paradigm to elicit automatic emotional processing through ERPs, in which target facial expressions were preceded by either affectively congruent or incongruent chords with a stimulus onset asynchrony (SOA) of 200 msec. Results revealed automatic emotional processing of major/minor triads (Experiment 1) and consonant/dissonant chords (Experiment 2) in controls, who showed longer reaction times and increased N400 for incongruent than congruent trials, while amusics failed to exhibit such a priming effect at both behavioral and electrophysiological levels. In Experiment 3, we further examined conscious emotional evaluation of the same chords in amusia. Results showed that amusics were unable to consciously differentiate the emotions conveyed by major and minor chords and by consonant and dissonant chords, as compared with controls. These findings suggest the impairment in automatic and conscious emotional processing of music in amusia. The implications of these findings in relation to musical emotional processing are discussed.

Auditory localization accuracy and auditory spatial discrimination in children with auditory processing disorders.

The present study investigated spatial hearing in children aged 6-12 years diagnosed with Auditory Processing Disorders (APD) and compared their results to those of a group of control children matched in age. Sound source localization accuracy was quantified using an absolute localization task and sound source discrimination by measuring the minimum audible angle. Low- and high-frequency noise bursts were presented from eight loudspeaker positions in the left and right hemifields (0°, 30, 60°, and 90° azimuth). Median absolute localization accuracy did not differ between children with APD and control children. However, the intra-individual variability of pointing behavior was higher for children with APD. In contrast, children with APD had significantly higher minimum audible angle thresholds than control children. These findings show that APD impairs sound source discrimination, but does not affect the median relationship between actual and judged sound source locations.

Talker normalization in typical Cantonese-speaking listeners and congenital amusics: Evidence from event-related potentials.

Despite the lack of invariance in the mapping between the acoustic signal and phonological representation, typical listeners are capable of using information of a talker's vocal characteristics to recognize phonemes, a process known as "talker normalization". The current study investigated the time course of talker normalization in typical listeners and individuals with congenital amusia, a neurodevelopmental disorder of refined pitch processing. We examined the event-related potentials (ERPs) underling lexical tone processing in 24 Cantonese-speaking amusics and 24 typical listeners (controls) in two conditions: blocked-talker and mixed-talker conditions. The results demonstrated that for typical listeners, effects of talker variability can be observed as early as in the N1 time-window (100-150 ms), with the N1 amplitude reduced in the mixed-talker condition. Significant effects were also found in later components: the N2b/c peaked significantly earlier and the P3a and P3b amplitude was enhanced in the blocked-talker condition relative to the mixed-talker condition, especially for the tone pair that is more difficult to discriminate. These results suggest that the blocked-talker mode of stimulus presentation probably facilitates auditory processing and requires less attentional effort with easier speech categorization than the mixed-talker condition, providing neural evidence for the "active control theory". On the other hand, amusics exhibited comparable N1 amplitude to controls in both conditions, but deviated from controls in later components. They demonstrated overall later N2b/c peak latency significantly reduced P3a amplitude in the blocked-talker condition and reduced P3b amplitude irrespective of talker conditions. These results suggest that the amusic brain was intact in the auditory processing of talker normalization processes, as reflected by the comparable N1 amplitude, but exhibited reduced automatic attentional switch to tone changes in the blocked-talker condition, as captured by the reduced P3a amplitude, which presumably underlies a previously reported perceptual "anchoring" deficit in amusics. Altogether, these findings revealed the time course of talker normalization processes in typical listeners and extended the finding that conscious pitch processing is impaired in the amusic brain.

On the definition of APD and the need for a conceptual model of terminology.

Objective: To consider the definition of auditory processing disorder (APD). Design: Narrative review and opinion piece. Study sample: Considerations of definition drawn primarily from the fields of philosophy, audition, learning and language. Results: The problem of defining APD appears genuine. Current and previous definitions of APD are nominal in nature, being both stipulative (offering explicit and arbitrary adoptions of meaning relation between words) and operational (creating rules that stipulate how the terms might apply to particular cases). Such definitions survive by consensus and perceived heuristic value in a manner that fails to achieve closure as arguments about their validity remain relative. Conclusion: A conceptual model of APD terminology is needed that considers nominal, conceptual and real definitions as well as different purposes for defining APD within professional and public domains. A framework for such a conceptual model of APD terminology is offered.

Efficacy of a deficit specific auditory training program for remediation of temporal patterning deficits.

Objective: To determine the efficacy of a targeted auditory training programme as a remediation approach for children diagnosed with a temporal patterning disorder. Design: Temporal Patterning scores were determined at two-time points pre-intervention and again post-training. Measures were then repeated in half of the participants after a further non-training period to determine the sustainability of effects. Cognitive skills and outcome measures were assessed at all time-points. Study Sample: Ten children aged between 7 and 12 years of age, diagnosed with a temporal patterning processing disorder, were enrolled in the training programme. Results: A group mean of 9.2 hours training was completed. Conclusion: Significant, sustainable improvements on the Frequency Pattern Test were found (2.5 SD increase in score relative to mean of age matched-peers) at the completion of training. Duration of training did not predict the degree of improvement. Cognitive skills did not show significant changes in ability. Significant, sustainable improvements in temporal patterning ability were seen after completion of the training programme. No associated changes in cognitive skills were seen, suggesting independence of the skills. Deficit-specific approaches are available across the traditional test battery, however, determining the appropriate management plan for a child diagnosed with an auditory processing disorder requires a patient-centric approach.