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Children with auditory processing disorder (APD) experience hearing difficulties, particularly in the presence of competing sounds, despite having normal audiograms. There is considerable debate on whether APD symptoms originate from bottom-up (e.g., auditory sensory processing) and/or top-down processing (e.g., cognitive, language, memory). A related issue is that little is known about whether functional brain network topology is altered in APD. Therefore, we used resting-state functional magnetic resonance imaging data to investigate the functional brain network organization of 57 children from 8 to 14 years old, diagnosed with APD (n = 28) and without hearing difficulties (healthy control, HC; n = 29). We applied complex network analysis using graph theory to assess the whole-brain integration and segregation of functional networks and brain hub architecture. Our results showed children with APD and HC have similar global network properties -i.e., an average of all brain regions- and modular organization. Still, the APD group showed different hub architecture in default mode-ventral attention, somatomotor and frontoparietal-dorsal attention modules. At the nodal level -i.e., single-brain regions-, we observed decreased participation coefficient (PC - a measure quantifying the diversity of between-network connectivity) in auditory cortical regions in APD, including bilateral superior temporal gyrus and left middle temporal gyrus. Beyond auditory regions, PC was also decreased in APD in bilateral posterior temporo-occipital cortices, left intraparietal sulcus, and right posterior insular cortex. Correlation analysis suggested a positive association between PC in the left parahippocampal gyrus and the listening-in-spatialized-noise -sentences task where APD children were engaged in auditory perception. In conclusion, our findings provide evidence of altered brain network organization in children with APD, specific to auditory networks, and shed new light on the neural systems underlying children's listening difficulties., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Objective: To systematically assess the body of literature using N400 and P600 as they relate to people with aphasia. The primary aim was to reveal patterns in the literature which could be used to direct future research in the development of clinically relevant Event-Related Potentials (ERPs) for language assessment, while also identifying gaps in existing knowledge and highlight areas of further inquiry., Methods: A literature search was performed on studies published before May 2021. Relevant studies on aphasia and the two ERPs of interest were assessed for quality, and the relationship between aphasia and these ERPs was explored., Results: A total of 721 articles were identified, with 30 meeting inclusion criteria. Although there is significant variation in the literature, this scoping review revealed people with aphasia show reduced amplitude, delayed latency and different distribution compared to controls, and that ERPs are modulated by severity of aphasia., Conclusions: To develop a relevant clinical tool for the management of aphasia, future research must strive to improve consistency within ERP methodology, with a greater number of diverse aphasia subtypes included in research., Significance: This scoping review reveals N400 and P600 represent promising potential biomarkers for the diagnosis and ongoing management of aphasia., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Purpose: 'Affective prosody' defines the supra-segmental features of speech that, when manipulated, can change the type and intensity of emotion conveyed by the speaker. Although the right hemisphere is predominantly linked to the processing of affective prosodic cues, existing literature also suggests that damage to the left hemisphere can result in similar deficits. This study aims to demonstrate, and add to the evidence, that patients with left-hemisphere injury experience difficulties with affective prosodic perception and production, measured via a new combination of assessments and analyses. It is also hypothesised that aphasia severity will be correlated with impaired processing of affective prosody., Results: Stroke and control participants differed significantly on prosody perception tests of matching auditory affective cues to visual images. Prosodic production was measured by participants vocalising different affective expressions of words and monosyllables - from which significant differences were found in perceptual judgements of emotion accuracy and intensity, and acoustic analyses of pitch range and variance. There were significant correlations between participants' Western Aphasia Battery (WAB) scores, quality of life, and prosody production., Conclusion: Individuals with left-hemisphere damage after stroke have impaired affective prosodic perception and production that may be associated with reduced quality of life., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Objective: We sought to examine whether oscillatory EEG responses to a speech stimulus in both quiet and noise were different in children with listening problems than in children with normal hearing., Methods: We employed a high-resolution spectral-temporal analysis of the cortical auditory evoked potential in response to a 150 ms speech sound /da/ in quiet and 3 dB SNR in 21 typically developing children (mean age=10.7 years, standard deviation=1.7) and 44 children with reported listening problems (LP) with absence of hearing loss (mean age=10.3 years, standard deviation=1.6). Children with LP were assessed for auditory processing disorder (APD) by which 24 children had APD, and 20 children did not. Peak latencies, magnitudes, and frequencies were compared between these groups., Results: Children with LP had frequency shifts in the theta, and alpha bands (p<0.05), and children with LP+APD had additional frequency (p<0.01) and latency shifts (p<0.05) in the upper beta and in the lower gamma bands., Conclusions: These results provide evidence for differences in higher level modulatory processing in children with LP, and that APD is driven by differences in early auditory encoding., Significance: These findings may better guide future research toward improving the differential diagnosis and treatment of listening problems in this population of children., (Published by Elsevier Ireland Ltd.)

Objectives: To examine behavioural and neural processing of pitch cues in adults with normal hearing (NH) and adults with sensorineural hearing loss (SNHL)., Methods: All participants completed a test of behavioural sensitivity to pitch cues using the TFS1 test (Moore and Sek, 2009a). Cortical potentials (N1, P2 and acoustic change complex) were recorded in response to frequency shifted (deltaF) tone complexes in an 'ABA' pattern., Results: The SNHL group performed more poorly than the NH group for the TFS1 test. P2 was more reflective of pitch differences between the complexes than N1. The presence of acoustic change complex in response to the TFS transitions in the ABA stimulus varied with deltaF. Acoustic change complex amplitudes were reduced for the group with SNHL compared to controls., Conclusion: Behavioural performance and cortical responses reflect pitch processing depending on the salience of pitch cues., Significance: These data support the use of cortical potentials and behavioural sensitivity tests to measure processing of complex acoustic cues in people with hearing loss. This approach has potential for evaluation of benefit from auditory training and hearing instrument digital signal processing strategies., (Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

Objective: Auditory evoked potentials (EP) were used to examine the neural processing of personal-emotional and neutral words, in a group of 14 people with post-stroke aphasia and an equal sized control group to determine whether the EP differed between groups and word types., Methods: Effects of the emotional value of the words and participant group were assessed on EP. Latencies and amplitudes of EP were analyzed for the two groups (aphasia and control) in response to word type (emotional and neutral)., Results: N1 amplitudes were smaller and P2 and P3 were delayed in the aphasia group, for both word types, indicating effects of stroke on processing of both neutral and emotional words. P3 amplitudes were larger for emotional words in both groups. These differences in late cortical responses between word types for both groups suggest distinct neural networks involved in the response to emotional and neutral words, even with post-stroke language impairment., Conclusions: The neurophysiological processing of affective speech in aphasia has been revealed. This opens up the interpretation of these results to the critical assessment and therapeutic identification of emotional language in people with aphasia., Significance: This study has implications not just for aphasia but allows for further exploration of other neurological conditions., (Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

Objective: To determine stimulus level effects on speech-evoked cortical auditory evoked potentials (CAEPs) in infants for a low (/m/) and high (/t/) frequency speech sound., Methods: CAEPs were recorded for two natural speech tokens, /m/ and /t/. Participants were 16 infants aged 3-8months with no risk factors for hearing impairment, no parental concern regarding hearing or development, and normal tympanograms and otoacoustic emissions. Infants were either tested at levels of 30, 50, and 70dB SPL or at 40, 60, and 80dB SPL, in counterbalanced order., Results: Input-output functions show different effects of increasing sound level between stimuli. There were minimal changes in latency with increase in level for /t/. For /m/, there were approximately 50-60ms latency increases at soft compared to loud levels. Amplitudes saturated at moderate-high levels (60-80dB SPL) for both stimuli., Conclusions: Infants' CAEP input-output functions differ for /t/ versus /m/ and differ from those previously reported for adults for other stimuli. Effects of stimulus and level on CAEPs should be considered when using CAEPs for hearing aid or cochlear implant evaluation in infants., Significance: Speech-evoked CAEPs provide an objective measure of central auditory processing. Possible differences in CAEP growth between infants and adults suggest developmental effects on intensity coding by the auditory cortex., (Copyright © 2012. Published by Elsevier Ireland Ltd.)

Unlabelled: The present study investigated the immediate effects of eight altered auditory feedback (AAF) parameters on stuttering frequency during monologue speech production on two occasions. One of the modern commercially available portable anti-stuttering devices, "The Pocket Speech Lab" (Casa Futura Technologies) was used in the study to produce the auditory feedback alterations. Six types of combined delayed auditory feedback (DAF) and frequency shifted auditory feedback (FAF) and two types of DAF alone were tested for eight participants aged 16-55 years, with stuttering severity ranging from mild to severe. The present study found that AAF is an effective means to reduce stuttering frequency during monologue speech production. All eight AAF experimental conditions reduced stuttering frequency, however, there was substantial variability in the stuttering reduction effect across experimental conditions and across participants. There was also instability in stuttering reduction across the two testing sessions. On average, a 75 ms time delay on its own and a combination of the 75 ms time delay and a half octave downward frequency shift were found to be more effective than other combinations of AAF parameters that were investigated., Educational Objectives: After reading this paper, the reader should be able to (1) summarize the research investigating the effect of altered auditory feedback on stuttering frequency during monologue speech production; (2) describe the stuttering reduction effect of the eight parameters of AAF tested during monologue speech production; and (3) discuss the possible clinical implications of the use of AAF for stuttering treatment.

Objective: The aim of the research was to investigate auditory processing abilities in children with reading disorders using electrophysiological and behavioral tasks., Methods: Differences in auditory processing between control, compensated (age appropriate reading skills with a history of reading disorder), and reading disordered groups were systematically investigated., Results: The reading disorder group had significantly lower results than control and compensated reader groups for most tests in the reading and auditory processing test battery. All children with a reading disorder did not pass at least one behavioral test of auditory processing, and hence would be diagnosed clinically as having an auditory processing disorder (APD). The reading disorder group also had significantly smaller /ga/-evoked mismatch negativity (MMN) area than the control group. Compensated and control groups had similar results for the electrophysiological and behavioral auditory processing tests. Correlation analyses showed that reading fluency and accuracy and nonword scores (measured using Castle and Coltheart's word/nonword test) correlated significantly with most APD measures., Conclusions: The general profile of auditory processing deficits in children with reading disorder was a combination of deficits on frequency patterns (i.e. frequency pattern test) and absent or small /ga/-evoked MMN. Significant results from the correlation analyses support the co-morbidity of reading and auditory processing disorders., Significance: Children with reading disorders are likely to have auditory processing disorders.

Objective: This study determined the relationship between auditory evoked potential measures and speech perception in experienced adult cochlear implant (CI) users and compared the CI evoked potential results to those of a group of age- and sex-matched control subjects., Methods: CI subjects all used the Nucleus CI-22 implant. Middle latency response (MLR), obligatory cortical potentials (CAEP), mismatch negativity (MMN) and P3a auditory evoked potentials were recorded. Speech perception was evaluated using word and sentence tests., Results: Duration of deafness correlated with speech scores with poor scores reflecting greater years of deafness. Na amplitude correlated negatively with duration of deafness, with small amplitudes reflecting greater duration of deafness. Overall, N1 amplitude was smaller in CI than control subjects. Earlier P2 latencies were associated with shorter durations of deafness and higher speech scores. In general, MMN was absent or degraded in CI subjects with poor speech scores., Conclusions: Auditory evoked potentials are related to speech perception ability and provide objective evidence of central auditory processing differences across experienced CI users., Significance: Since auditory evoked potentials relate to CI performance, they may be a useful tool for objectively evaluating the efficacy of speech processing strategies and/or auditory training approaches in both adults and children with cochlear implants.