Central Auditory Processing Research Articles

Practice Trends in (C)APD Assessment and Management: A Survey of Audiologists in Kerala.

Aims Present study investigates the current trends in (Central) Auditory Processing Disorder [(C)APD] assessment and management practices among Audiologists practicing in Kerala, India. Materials and Methods The questionnaire for the survey was developed based on the Knowledge, Attitude, and Practices(KAP) model and underwent validation by experts in Audiology. Online survey was conducted to collect data from Audiologists practicing in Kerala, with a valid RCI-CRR number. Descriptive statistics were used to analyze the responses. Results The majority of participants held bachelor's degrees and completed training modules on the assessment of (C)APD during their undergraduate studies. However, clinical exposure was very low. Even though 59.2% of participants reported that they were performing screening for (C)APD, the use of standardized screening tools was limited. Only 35% of participants reported that they were performing diagnostic evaluation. However, the rest of the participants used only speech-in-noise tests for (C)APD evaluation. The participants who performed management of (C)APD were even fewer, at only 13.4%. Lack of facilities, inadequate patient load, and lack of practical exposure were major obstacles to (C)APD assessment and management. The majority of participants strongly agreed that Audiologists are the most qualified persons to deal with (C)APD; however, the practice trends obtained from the study suggest that Audiologists have a really poor practice in this area. Conclusion The study highlights the need for standardized assessment tools, improved training opportunities, and increased awareness among Audiologists regarding (C)APD. Multidisciplinary collaboration and further research are essential for enhancing (C)APD assessment and management practices in Kerala.

Central Auditory Processing Abilities in Children with Non-Syndromic Cleft Lip/and Palate-a Behavioural Study.

The present study aimed to assess the central auditory processing abilities and working memory in children with non-syndromic cleft lip and palate (NSCLP) and to compare with the developed normative and craniofacially normal peers. Sixteen NSCLP children aged 7 to 12 years and fifteen craniofacially normal peers were recruited in this study. Speech perception in noise Kannada (SPIN-K), gap detection threshold (GDT), dichotic consonant-vowel (DCV), and masking level difference (MLD) tests were administered to assess various central auditory processing abilities. Working memory abilities were assessed by using forward-digit span and backward-digit span tests. The results showed significant differences in SPIN-K, dichotic CV, GDT, forward digit, and backward digit span scores between children with NSCLP and craniofacially normal peers. Thus, it can be concluded from the present study that children with NSCLP have a risk of developing auditory processing deficits. To conclude, assessment of central auditory processing abilities in children with NSCLP is recommended.

Exploring auditory temporal resolution and dichotic listening skills among individuals with type 2 diabetes mellitus

The study aimed to explore the auditory temporal resolution and dichotic listening skills in patients with type 2 diabetes mellitus (T2DM) and identify associated health-related factors. Using a cross-sectional design, 87 adults with T2DM and 48 non-diabetic controls, all with normal hearing, participated. The two central auditory processing (CAP) skills were assessed through the Gaps-In-Noise (GIN) and Dichotic-Digits Listening (DDL) tests. T2DM participants underwent blood tests to measure various health-related factors. In the GIN test, the shortest gap threshold (GapTh) obtained across both ears was significantly higher in the diabetic group (9.1 ± 2.4 ms) compared to the non-diabetic group (7.5 ± 1.5 ms), and the score of correctly identified gaps (GapSc) in the diabetic group (45±11 %) was significantly lower than GapSc in the non-diabetic group (52±9 %), p < 0.001. In the DDL test, the free-recall score (73.8 ± 18.5 %) across both ears and the right-ear advantage (-1.3 ± 20.6 %) in the diabetic group were significantly lower than the free-recall score (85.8 ± 11.9 %) and right-ear advantage (6.9 ± 11.9 %) in the non-diabetic group, p < 0.005. Furthermore, the duration of diabetes, eGFR level, retinopathy, carotid plaque, fasting blood glucose level, and HDL-C (good cholesterol) level were factors significantly associated with performances in the GIN and/or DDL tests for T2DM participants. In conclusion, individuals with T2DM are at risk of reduced auditory processing skills in temporal resolution and dichotic listening, impacting their speech understanding. Six health-related factors were identified as significantly associated with CAP skills in T2DM patients.

Does migraine affect central auditory processing abilities?

ObjectiveMigraine is a neurological disease associated with an altered cortical excitability level. Several studies have investigated the relationship between migraine and central auditory processing (CAP), with deficits in CAP being common among migraine patients. However, studies on the factors affecting these CAP changes observed in migraine patients are still few and controversial. This study aims to investigate CAP changes in migraine patients with Duration Pattern Test (DPT) and Frequency Pattern Test (FPT), which have not been used in previous studies. MethodsSixty subjects were divided into two groups and one migraine subgroup: control group, twenty normal healthy subjects, fourty subjects diagnosed with migraine. They were evaluated using the CAP test including DPT and FPT. To identify the variables and possible effects of the variables, a questionnaire describing the characteristics of migraine features was administered to participants with migraine. ResultsNo significant difference was found the between the control and study group in CAP tests scores. No significant correlation was found between migraine characteristics and CAP tests scores. Males had significantly higher FPT scores in both ears than females (p<0.05). Significant statistical negative correlation was found between age and FPT scores for both ears and left DPT scores (p<0.05). ConclusionAlthough migraine patients generally showed lower CAP ability than the control group, no significant difference was observed between them. This was also valid for subgroups of migraine. However, as age increased in the migraine group, a significant decrease in CAP performance was observed. It was observed that male migraine patients had better CAP ability, especially FPT scores. Migraine may affect performance in CAP depending on gender and age factors.

Mismatch Negativity in Children with Deficits in Auditory Abilities.

Introduction Mismatch negativity (MMN) represents a negative component of event-related potentials, which is mentioned by guidelines as an important tool to provide measurable data regarding the functionality of the auditory system in acoustic processing. However, the literature still lacks reliable data that can support the clinical use of this potential in the complementary diagnosis of central auditory processing (CAP) disorder (CAPD). Objectives To analyze whether MMN assessment might be associated with the CAP behavioral test battery, as well as to assess the effects of auditory ability deficits on MMN responses in the pediatric population. Methods In total, 45 age-matched children participated in the study. They were submitted to the CAP behavior assessment and to MMN. The children were tested with a combination of speech contrast consisting of acoustic syllables [da] versus [ta], governed by the oddball paradigm. Results Mismatch negativity did not show a direct association with a single test but with the combination of the four tests used as a behavioral test battery to identify CAPD. The results also indicated that the auditory ability deficits influenced the measurement of MMN latency ( p = 0.003*), but not the amplitude ( p = 0.857) or the area ( p = 0.577). Conclusion Mismatch negativity was shown to be statistically associated with the battery of tests used to identify deficits in auditory abilities in the studied sample rather than with a single behavioral test. The deficits in auditory abilities were observed in the MMN latency. Mismatch negativity can be used to assess children with CAPD.

Hearing Loss and Cognitive Decline in the Aging Population: Emerging Perspectives in Audiology.

In this perspective article, the author explores the connections between hearing loss, central auditory processing, and cognitive decline, offering insights into the complex dynamics at play. Drawing upon a range of studies, the relationship between age-related central auditory processing disorders and Alzheimer's disease is discussed, with the aim of enhancing our understanding of these interconnected conditions. Highlighting the evolving significance of audiologists in the dual management of cognitive health and hearing impairments, the author focuses on their role in identifying early signs of cognitive impairment and evaluates various cognitive screening tools used in this context. The discussion extends to adaptations of hearing assessments for older adults, especially those diagnosed with dementia, and highlights the significance of objective auditory electrophysiological tests. These tests are presented as vital in assessing the influence of aging and Alzheimer's disease on auditory processing capabilities and to signal cognitive dysfunction. The article underscores the critical role of audiologists in addressing the challenges faced by the aging population. The perspective calls for further research to improve diagnostic and therapeutic strategies in audiology, and emphasizes the need for a multidisciplinary approach in tackling the nexus of hearing loss, auditory processing, and cognitive decline.

Central Auditory Processing Disorder Screening Inventory LIFE-R: Turkish Adaptation, Validity and Reliability Study

Amaç: Bu çalışmanın amacı, orijinal adı LIFE-R (Listening Inventory For Education-Revised) olan envanterin Türkçe çeviri, adaptasyon ve geçerlilik-güvenirlik çalışmasını yaparak, ülkemize (Santral) İşitsel İşlemleme Bozukluğu’nun taramasında kullanılabilecek bir değerlendirme materyalini kazandırmaktır. Gereç ve Yöntem: Çalışmaya 9-18 yaşları arasında, bilinen/tanısı konmuş işitme, konuşma ya da öğrenme bozukluğu olmayan 115 ilköğretim ve lise öğrencisi ve öğretmenleri dahil edilmiştir. Envanterin dil geçerliliği çalışması yapılmış, gerekli düzenlemeler yapıldıktan sonra dilsel eşdeğerliliğe sahip olduğu saptanarak güvenirlik ve geçerlilik analizleri tamamlanmıştır. Bulgular: Envanterin güvenilirliğinin belirlenmesi amacıyla ölçek ve alt boyutları için Cronbach-alfa iç tutarlılık katsayıları hesaplanmıştır. Bu değerlerin yüksek çıkması, ölçeğin güvenilir bir ölçme aracı olduğunu göstermiştir. Yapı geçerliliğine ilişkin kanıtların elde edilmesi sonucunda özgün formun beş faktörlü yapısına uygun olduğu ve faktör analizi sonucunda yüksek yük değerlerine sahip olunduğu görülmüştür. Ölçeklerdeki maddelerin anlamlarındaki tutarlılığa bakıldığında orijinal ve Türkçe formundan elde edilen maddelerin toplam puanları arasında (p&lt;0.01) pozitif yönde anlamlı bir ilişki bulunmuştur ve ölçeğin orijinal kültürdeki anlamları ile eşdeğerlik sağlanmıştır. Sonuçlar: Türkçe LIFE-R (TLIFE-R), özellikle okul çağındaki çocukların SİİB taramasında geçerli ve güvenilir bir ölçek olarak kullanılabilir. SİİB tarama programları, risk altındaki çocukların erken tespiti ve gerekli önleyici ve eğitici/rehabilite edici yaklaşımların başlatılması açısından son derece önemlidir.

Background and Rationale for a Transitional Intervention for Debilitating Hyperacusis.

This report provides the experimental, clinical, theoretical, and historical background that motivated a patented transitional intervention and its implementation and evaluation in a field trial for mitigation of debilitating loudness-based hyperacusis (LH). Barriers for ameliorating LH, which is differentiated here from other forms of hyperacusis, are delineated, including counterproductive management and treatment strategies that may exacerbate the condition. Evidence for hyper-gain central auditory processes as the bases for LH and the associated LH-induced distress and stress responses are presented. This presentation is followed by an overview of prior efforts to use counseling and therapeutic sound as interventional tools for recalibrating the hyper-gain LH response. We also consider previous efforts to use output-limiting sound-protection devices in the management of LH. This historical background lays the foundation for our transitional intervention protocol and its implementation and evaluation in a field trial. The successful implementation and evaluation of a transitional intervention, which we document in the outcomes of a companion proof-of-concept field trial in this issue, build on our prior efforts and those of others to understand, manage, and treat hyperacusis. These efforts to overcome significant barriers and vexing long-standing challenges in the management and treatment of LH, as reviewed here, are the pillars of the transitional intervention and its primary components, namely, counseling combined with protective sound management and therapeutic sound, which we detail in separate reports in this issue.

Central Auditory Processing Deficit in Children Diagnosed with Autism Spectrum Disorder

Purpose: The study aims to check the presence of auditory processing deficit in children diagnosed with autism spectrum disorder.Methods: A total of 10 subjects within the age range of 6-10 years diagnosed with autism spectrum disorder were recruited for the study. Buffalo model questionnaire (child form) for CAPD was given to the parents of the children with autism and scores were noted. Auditory cognition which is a sub category of auditory processing was assessed for each subject with the help of Angel sound software version 5.08.03 by Emily Shannon Fu Foundation. Forward digit test was done and the auditory memory of the participant was checked. The result obtained from the subjective perception of parents and objective evaluation was compared and the correlation was checked.Results: The questionnaire given to the parents had different subsections and questions included in the category of memory revealed poor scores. Similarly, the scores obtained for forward digit test was reduced for the children diagnosed with autistic spectrum disorder when compared to the normative given by the software. The children were able to memorize maximum of only 3 digits.Conclusions: It can be concluded that there is a relation between and subjective perception of parents of children with autism and objective evaluation of auditory processing. In our study, the scores for auditory cognition test are reduced for children with autism. Autistic people with auditory processing disorders can hear, but they have difficulty understanding what they hear. Auditory processing disorder is a crucial pathology of the autistic disorder.

Central auditory functions in post-COVID-19 adults; a case control study

BackgroundThis study aimed to evaluate the central auditory abilities in post-coronavirus disease 2019 (COVID-19) adults by using Central Auditory Tests (CATs). This study included a complaining group (GI), a non-complaining group (GII), and a control healthy group (GIII). All subjects were evaluated using CATsResultsResults demonstrated statistically significant differences across groups as regards Speech Perception in Noise Test (SPIN), Duration Pattern Sequence Test (DPT), Gap in Noise Test (GIN), and Memory Test (ANOVA, p-value ≤ 0.05). The post-hoc test revealed that, except for recognition memory, both study groups showed statistically significant differences from the control group. Also, significant differences were detected between both GI and GII groups regarding SPIN−10 signal-to-noise ratio (S/N), DPT, GIN threshold, memory for content, and memory for sequenceConclusionsCOVID-19 led to central auditory processing disorders (c)APD.

Development and Evaluation of the Italian Version of the Dichotic Digit Test: Insights from 39 Normal-Hearing Children Aged 11 to 13 years.

BACKGROUND The dichotic digit test (DDT) is one of the tests for the behavioral assessment of central auditory processing. Dichotic listening tests are sensitive ways of assessing cortical structures, the corpus callossum, and binaural integration mechanisms, showing strong correlations with learning difficulties. The DDT is presently available in a number of languages, each appropriate for the subject's native language. However, there is presently no test in the Italian language. The goal of this study was to develop an Italian version of the one-pair dichotic digit test (DDT-IT) and analyze results in 39 normal-hearing Italian children 11 to 13 years old. We used 2 conditions of presentation: free recall and directed attention (left or right ear), and looked at possible effects of sex and ear side. MATERIAL AND METHODS This study involved 3 steps: creation of the stimuli, checking their quality with Italian speakers, and assessment of the DDT-IT in our subject pool. The study involved 39 children (26 girls and 13 boys), aged 11-13 years. All participants underwent basic audiological assessment, auditory brainstem response, and then DDT-IT. RESULTS Results under free recall and directed attention conditions were similar for right and left ears, and there were no sex or age effects. CONCLUSIONS The Italian version of DDT (DDT-IT) has been developed and its performance on 39 normal-hearing Italian children was assessed. We found there were no age or sex effects for either the free recall condition or the directed attention condition.

Two-year Prevalence of Central Auditory Processing Disorders in Children.

Central auditory processing disorder (CAPD) refers to difficulties in processing audible signals not attributable to impaired hearing sensitivity or mental impairment. The demographic characteristics of pediatric CAPD and its prevalence are still debatable. Due to varied definitions and differences in the diagnostic criteria for CAPD, the approximate prevalence measure varies from 0.5 to 7% of the population. Thus, a retrospective study on prevalence in individuals with CAPD was conducted. A total of 3537 cases with ear-related problems were reported to Audiology OPD at All India Institute of Speech and Hearing from June 2017 to July 2019 between the age range of 6-18 years. Of these, 32 cases were diagnosed with CAPD, and this data was available for review. The prevalence of individuals with CAPD reported in this duration was 0.7%. The results also revealed that the prevalence was higher among males and individuals of lower socio-economic status. Their significant symptoms were poor academic performance and difficulty following commands or instructions. The data also revealed that speech perception in noise was the most affected process, followed by binaural integration in these individuals. The study provides insight into the vulnerable population who can get CAPD (e.g., children and males or people from lower socio-economic backgrounds).

Normative values for tests of central auditory processing disorder in children aged from 6 to 12 years old

IntroductionCentral auditory processing disorders (CAPD) can significantly affect the daily functioning of a child, and the first step in determining whether rehabilitation procedures are required is a proper diagnosis. Different guidelines for making diagnoses have been published in the literature, and in various centers normative values for psychoacoustic tests of CAPD have been used internally. The material presented in this paper is based on more than 1000 children and is the largest collection so far published. The aim of this study is to present normative values for tests assessing CAPD in children aged 6 to 12 years, divided by age at last birthday. MethodWe tested 1037 children aged 6 to 12 years who were attending primary schools and kindergartens. The criteria for inclusion were a normal audiogram, intellectually normal, no developmental problems, and no difficulties in auditory processing. To evaluate auditory processing all children were given three tests on the Senses Examination Platform: the Frequency Pattern Test (FPT), Duration Pattern Test (DPT), and Dichotic Digit Test (DDT). ResultsThe results from 1,037 children allowed us to determine normative values for FPT, DPT, and DDT in seven different age groups (6 through to 12 years). We developed a newapproach, based on quantile-based norms, to determine normative values in each group. Three categories – average, below-average, and above-average – allow for a broader but more realistic interpretation than those used previously. We compare our results with published standards. ConclusionsOur study is the largest normative database published to date for CAPD testing, setting a standard for each child by age in years. We used the Senses Examination Platform, a universal tool, to unify standards for the classification of CAPD. Our study can serve as a basis for the development of a Polish model for the diagnosis of CAPD.

Blast Exposure Alters Synaptic Connectivity in the Mouse Auditory Cortex.

Blast exposure can cause auditory deficits that have a lasting, significant impact on patients. Although the effects of blast on auditory functions localized to the ear have been well documented, the impact of blast on central auditory processing is largely undefined. Understanding the structural and functional alterations in the central nervous system (CNS) associated with blast injuries is crucial for unraveling blast-induced pathophysiological pathways and advancing development of therapeutic interventions. In this study, we used electrophysiology in combination with optogenetics assay, proteomic analysis, and morphological evaluation to investigate the impairment of synaptic connectivity in the auditory cortex (AC) of mice following blast exposure. Our results show that the long-range functional connectivity between the medial geniculate nucleus (MGN) and AC was impaired in the acute phase of blast injury. We also identified impaired synaptic transmission and dendritic spine alterations within 7 days of blast exposure, which recovered at 28 days post-blast. Additionally, proteomic analysis identified a few differentially expressed proteins in the cortex that are involved in synaptic signaling and plasticity. These findings collectively suggest that blast-induced alterations in the sound signaling network in the auditory cortex may underlie hearing deficits in the acute and sub-acute phases after exposure to shockwaves. This study may shed light on the perturbations underlying blast-induced auditory dysfunction and provide insights into the potential therapeutic windows for improving auditory outcomes in blast-exposed individuals.

Ośrodkowe zaburzenia przetwarzania słuchowego w świetle specjal- nych potrzeb edukacyjnych – luka w systemie orzeczniczym

This paper aims to present a niche in issuing certificates of special education for children with central auditory processing disorders. Central auditory processing disorders (CAPD) – one type of neurodi- versity – are more commonly diagnosed among school-aged children, but they are also present in adults. Auditory processing disorders cause many learning difficulties in children, including those in understanding questions and instructions, reading and writing, remembering new information, foreign language learning difficulties, and more. Recommendations and guidelines for the whole diagnostic process, therapy, and reha- bilitation, as well as supporting children with central auditory processing disorders need to be introduced as up to now children with CAPD are not guaranteed any help by the system.

Assessment of Peripheral and Central Auditory Processing after Treatment for Idiopathic Sudden Sensorineural Hearing Loss.

Introduction When cases of idiopathic sudden sensorineural hearing loss (SSNHL) are treated successfully, most clinicians assume the normality and symmetry of the auditory processing. This assumption is based on the recovery of the detection ability on the part of the patients, but the auditory processing involves much more than detection alone. Since certain studies have suggested a possible involvement of the central auditory system during the acute phase of sudden hearing loss, the present study hypothesized that auditory processing would be asymmetric in people who have experienced sudden hearing loss. Objective To assess the physiologic and electrophysiological conditions of the cochlea and central auditory system, as well as behavioral discrimination, of three primary aspects of sound (intensity, frequency, and time) in subjects with normal ears and ears treated successfully for SSNHL. Methods The study included 19 SSNHL patients whose normal and treated ears were assessed for otoacoustic emissions, speech auditory brainstem response, intensity and pitch discrimination, and temporal resolution in a within-subject design. Results The otoacoustic emissions were poorer in the treated ears compared to the normal ears. Ear- and sex-dependent differences were observed regarding otoacoustic emissions and pitch discrimination. Conclusion The asymmetrical processing observed in the present study was not consistent with the hearing threshold values, which might suggest that the central auditory system would be affected regardless of the status of the peripheral hearing. Further experiments with larger samples, different recovery scenarios after treatment, and other assessments are required.

A Systematic Review on Hearing and Balance in Patients with Chronic Kidney Disease with and Without Hemodialysis.

Exploring the auditory and vestibular manifestations associated with chronic kidney disease (CKD) has been growing in recent years. Understanding these complaints in CKD patients is crucial for comprehensive patient care. This review aimed to investigate the audiological findings and profiles across various stages of CKD and guide for informed decision-making in their management. Relevant articles from PubMed, ScienceDirect, EBSCO Medline, SCOPUS, Google Scholar, and Clinical Key were identified for review. The selected articles were published from 2008 to 2023 and written in English language. A total of 41 articles on auditory and vestibular assessments in CKD were eligible for review. Pure tone audiometry (PTA), immittance audiometry (IA) and otoacoustic emissions (OAEs) were the most commonly employed hearing tests respectively, with a higher frequency of utilization in hemodialysis cases compared to non-hemodialysis ones. Also, vestibular evoked myogenic potentials (VEMPs) emerged as the most popular vestibular test among hemodialysis patients while questionnaires were frequently employed in CKD patients. Moreover, our analysis suggests a potential association between the duration of hemodialysis and the development of tinnitus and vertigo. Abnormalities were also observed in auditory brainstem response (ABR), speech audiometry, central auditory processing tests and videonystagmography (VNG) assessment in hemodialysis and non-hemodialysis patients. CKD patients, particularly those undergoing hemodialysis, face a higher risk of hearing loss, tinnitus, and vestibular complaints. Performing otoacoustic emissions and vestibular-evoked myogenic potentials along with PTA on CKD patients, regardless of the disease stage is recommended to more effective management of audiovestibular complaints in these population.

The Directional Effects of Marker Frequencies on Across-Channel Temporal Gap Detection Tasks: An Experimental Study

Plain Language SummaryGap detection tests are essential while performing hearing assessments that are aimed to tap central auditory processing abilities. Different varieties of gap detection tests are evaluated for their sensitivity, and across-channel gap detection is noted to have high potential to detect central auditory processing disorders. However, any variations in the stimulus frequencies would impact the results of gap detection thresholds. Present study would enlighten the reader with the impact of such variations in stimuli on the outcome gap detection measures. The result of the study indicates when the two marker frequencies are close in nature (one-octave difference), then the order of their presentation did not change the outcome measures significantly. But, when the two marker frequencies are wide in nature (two-octave difference), then the order of their presentation changed the outcome measures significantly. The measured gap detection thresholds are better if high-frequency segment presented initially followed by the low frequency. Further, the study also provides valuable discussions on the results obtained. The study would add necessary understanding and precautions about the stimulus while using gap detection measures.

Treatment approaches of central auditory processing deficit

Treatment approaches of central auditory processing deficit

Portable automated rapid testing: Validation of automated testing on older listeners from India

Portable automated rapid testing (PART) is an iPad application (https://braingamecenter.ucr.edu/games/p-a-r-t/) capable of measuring various psychoacoustic thresholds in an automated and rapid format using commercially available headphones. The app has been validated previously in native speakers of English and an adapted version of the app has been validated in young normal hearing listeners from Mexico. Previous research from our labs indicated that the thresholds obtained using non-speech tasks did not differ significantly between the native and the non-native speakers of English while the native speakers of English had significantly better thresholds in the speech task. However, there was no significant difference in the amount of spatial release from masking between the groups. Here, we present psychoacoustic threshold data for a large cohort of older listeners from India with various English proficiencies. The thresholds obtained from this group will be compared against previously published thresholds based on native speakers of English. It is hypothesized that the results would be similar to what was found earlier with younger listeners from India. These results will give us the evidence to start using this app to measure thresholds of various central auditory processing measures in non-native speakers of English.