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

Auditory Processing Disorder: Protocols and Controversy

PURPOSE

This study examined current auditory processing disorder (APD) protocols and audiologists' perspectives on the active debate seen in the literature regarding the status of APD as a unique disorder.

METHOD

This study used a cross-sectional, nonexperimental survey design. The participants were 134 U.S. audiologists, representing diversity across experience level and work setting.

RESULTS

Popular APD tests from prior surveys remain popular, and a few new tests have emerged. Most audiologists use diverse strategies to identify potential comorbid disorders as part of their APD protocol, including multidisciplinary assessment and referral to other specialists. Most participants disagreed with the assertion that APD is not a unique disorder; however, many also pointed out that patients' struggles with listening need to be the primary focus of APD assessment and management, regardless of the label of the disorder. Qualitative analysis of participant comments on the controversy yielded six themes: Clinical Experience, Comorbidity, Listening Skills, Literature Support, Overdiagnosis, and More Information Needed.

CONCLUSION

Most participants consider APD to be a unique disorder, citing clinical experience and the literature for support; however, many also indicated APD is complicated by comorbidity and APD may be overdiagnosed.

Functional Hearing Difficulties in Veterans: Retrospective Chart Review of Auditory Processing Assessments in the VA Health Care System

PURPOSE

Approximately 23 million Americans might have functional hearing difficulties (FHDs) that are not well explained by their audiometric thresholds. Clinical management of patients with FHDs is the subject of considerable debate, with few evidence-based guidelines to direct patient care. A better understanding of the characteristics of patients who seek help for FHDs, as well as current audiological management practices, is needed to direct research efforts to the areas greatest opportunity for advancement of clinical care.

METHOD

A retrospective chart review was conducted examining the medical records of a random sample of 100 Veterans who underwent auditory processing assessments across the VA Health Care System between 2008 and 2020.

RESULTS

Patients were young to middle-age, often with previous traumatic brain injury or blast exposure. Mental health, sleep, and pain disorders were common. No consistent relationships emerged between specific patient factors and domains of auditory processing deficits. Low-gain hearing aids were provided to 35 patients, 69% of whom continued wearing their hearing aids for at least 2 years.

CONCLUSION

Future research should address the potential overlap in symptoms and treatment for comorbid health conditions and FHDs, as well as the conditions underlying successful hearing aid use in this patient population.

An analysis of Lilienfeld et al.'s (2015) problematic psychological terms

The language psychologists and other mental health professionals utilize impacts the formation of public perceptions concerning the practice of psychology. Psychologists from Warren, Calkins, Dunlap, Gardiner, and Ruckmich to Lilienfeld et al. have raised concerns about the clarity and use of problematic psychological terms. This study measured 309 mental health professionals' (1) recognition and use of 50 psychological terms identified as problematic by Lilienfeld et al., and (2) explored the jangle fallacy by providing potentially synonymous word-pairs for participants to rate for synonymity. Results of Part I indicated that 34 out of the 50 terms were not recognized as problematic by a significant majority of participants. Participants disagreed about whether or not six terms were problematic, and the remaining 10 terms were rated by a majority to be problematic. Results of Part II indicated a disagreement between participants regarding the synonymity of four word-pairs, and agreement regarding the synonymity (or lack thereof) of the remaining 16 word-pairs. These findings support the suggestion by Lilienfeld and colleagues that greater attention is needed in regard to problematic psychological terminology, including synonymous or jangling terminology.

Impaired Subcortical Processing of Amplitude-Modulated Tones in Mice Deficient for Cacna2d3, a Risk Gene for Autism Spectrum Disorders in Humans

Temporal processing of complex sounds is a fundamental and complex task in hearing and a prerequisite for processing and understanding vocalization, speech, and prosody. Here, we studied response properties of neurons in the inferior colliculus (IC) in mice lacking Cacna2d3, a risk gene for autism spectrum disorders (ASDs). The α₂δ3 auxiliary Ca²⁺ channel subunit encoded by Cacna2d3 is essential for proper function of glutamatergic synapses in the auditory brainstem. Recent evidence has shown that much of auditory feature extraction is performed in the auditory brainstem and IC, including processing of amplitude modulation (AM). We determined both spectral and temporal properties of single- and multi-unit responses in the IC of anesthetized mice. IC units of α₂δ3^−/− mice showed normal tuning properties yet increased spontaneous rates compared with α₂δ3^+/+. When stimulated with AM tones, α₂δ3^−/− units exhibited less precise temporal coding and reduced evoked rates to higher modulation frequencies (f_m). Whereas first spike latencies (FSLs) were increased for only few modulation frequencies, population peak latencies were increased for f_m ranging from 20 to 100 Hz in α₂δ3^−/− IC units. The loss of precision of temporal coding with increasing f_m from 70 to 160 Hz was characterized using a normalized offset-corrected (Pearson-like) correlation coefficient, which appeared more appropriate than the metrics of vector strength. The processing deficits of AM sounds analyzed at the level of the IC indicate that α₂δ3^−/− mice exhibit a subcortical auditory processing disorder (APD). Similar deficits may be present in other mouse models for ASDs.

Auditory Processing Intervention Program for school-aged children - development and content validation

PURPOSE

The study aimed at the development and content validation of an Auditory Processing Intervention Program for school-aged European Portuguese speaking children with Auditory Processing Disorder.

METHODS

The first step was the program's development and its instructions manual, which includes objectives, activities, procedures, materials, reinforcement, instructions, and verbal stimuli used, for the following auditory skills: auditory discrimination, auditory attention; auditory memory; auditory closure; figure-ground; auditory separation; auditory integration; binaural fusion; content validation was performed next, with two expert panels analyzing the program, through the use of a questionnaire. Content validity was calculated using the content validity index.

RESULTS

Program evaluation shows an excellent content validity. Some items were modified after analyzing the experts' comments and suggestions (e.g. instructions, intensity differences, main character).

CONCLUSION

This work allowed the development and content validation of an auditory processing intervention program, with verbal stimuli, selected according to strict linguistic criteria. In the future, the acceptability and efficacy of this program with the target population should be analyzed.

Combination of Comorbidities as a Reference Standard for Evaluating Auditory Processing Disorder: Response to the Letter to the Editor From Schow et al. (2021)

PURPOSE

Concerns expressed by Schow et al. (2021) around the evidence-based diagnostic criteria suggested by Ahmmed (2021a) are addressed here. The use of combination of comorbidities as a reference standard for evaluating auditory processing tests is a valid strategy, consistent with the Research Domain Criteria framework from the National Institute of Mental Health as well as the Standards for Reporting of Diagnostic Accuracy Studies. The correlations between auditory processing tests and some comorbidities in Ahmmed (2021a) were significant at p < .01. The low sensitivity and specificity reported was not related to the principle of using comorbidities as a reference standard but due to the choice of comorbidities combined in the reference standard. Ahmmed (2021a) suggested the option of inclusion of other comorbidities in addition to language impairment and impaired manual dexterity in the reference standard. Visual processing impairment could be considered as the additional comorbidity to improve sensitivity and specificity of the approach suggested by Ahmmed (2021a).

AudBility: Effectiveness of an online central auditory processing screening program

Objective

To contribute to the validation of AudBility, an online central auditory processing screening program, considering the tasks for age between 6 and 8 years-old, from the investigation of sensitivity and specificity, as well as to suggest a minimum central auditory processing (CAP) screening protocol in this age group.

Method

In the first stage of the study, 154 schoolchildren were screened. Children were aged between 6 and 8 years old, native speakers of Brazilian Portuguese. The auditory tasks of AudBility analyzed in this study were: sound localization (SL), auditory closure (AC), figure-ground (FG), dichotic digits—binaural integration (DD), temporal resolution (TR) and temporal frequency ordering (TO-F). In the second stage, 112 children attended to CAP assessment in the institution’s laboratory. The calculation of efficacy (sensitivity/specificity) was obtained through the construction of the ROC curve for the tests with more than five children altered in the diagnosis.

Results

For the 6–7-year-old age group the accuracy values were: AC (76.9%); FG (61.6%); DD 78.8% for the right ear and 84.4% for the left ear in females and 63.2% for the left ear in males; TR (77.1%) and TO-F (74.4% for the right ear and 82.4% for the left ear). For the 8-year-old age group the values were: FF (76.5%); DD (71.7% for the left ear for females and 77% for the right ear for males); TR (56.5%) and TO-F (54.1% for the right ear and 70% for the left ear).

Conclusions

AudBility showed variations in sensitivity and specificity values between the auditory tasks and age groups, with better effectiveness in schoolchildren between the ages of 6 and 7 than eight-year-olds, except for the FG task. For screening purposes, the application of the protocol involving five tasks for the 6 to 7-year-olds group and with four tasks for the 8-year-olds group is suggested.

Factor Analysis on Multiple Auditory Processing Assessment-2 and Listening in Spatialized Noise-Sentences Test in Children

Introduction There is need for greater understanding of tests used in assessing all aspects of auditory processing disorder (APD). This is important so that specific deficits can be identified and later remediated with the smallest possible test battery. The American Speech-Language-Hearing Association (ASHA) recommends five areas/domains for behavioral assessment: (a) temporal, (b) binaural (dichotic) separation/integration, (c) monaural low redundancy, (d) binaural interaction/localization/lateralization, and (e) auditory discrimination. Multiple-factor studies support the first three domains, which are most often used for APD assessment and which can be measured in a test battery normed within the United States (Multiple Auditory Processing Assessment-2 [MAPA-2]). This study was designed to determine if factored results from children would clarify whether a behavioral test (Listening in Spatialized Noise-Sentences Test [LiSN-S]) would factor within one of the first three domains or be separate, possibly within the fourth domain, binaural interaction. Method Fifty-one 8- and 9-year-olds with normal development and normal otoscopy and hearing responses bilaterally from 500 to 4000 Hz at 20 dB HL were recruited. Two sets of APD tests were administered: MAPA-2 and LiSN-S. Results Results verified the expected three-factor structure for MAPA-2. LiSN-S did not factor within one of those three, suggesting that some processes involved in the LiSN-S tasks require interactions between the two ears different from those involved in dichotic perception and thus better belong in the ASHA binaural interaction/lateralization domain. Conclusions Auditory processing abilities are sufficiently independent of each other that test batteries spanning the first three ASHA domains are not sensitive to at least some abilities in the fourth domain. This additional factor evidence is helpful. Future research should examine the utility of measuring additional factors within APD in order to achieve the most efficient and comprehensive test battery.

Validity of the Multiple Auditory Processing Assessment-2: A Test of Auditory Processing Disorder

Purpose A normative study using the Multiple Auditory Processing Assessment-2 (MAPA-2; Schow et al., 2018) was recently completed. With access to these data, the authors extend that work and support a definite construct for auditory processing disorder (APD). The goal here is to examine MAPA-2 reliability and validity (construct, content, and concurrent). Evidence for the APD construct is further buttressed by measures of sensitivity and specificity. Results of MAPA-2 testing on children diagnosed with learning disability (LD), attention-deficit/hyperactivity disorder (ADHD), and specific language impairment (SLI) are included. Method Normative data (previously published as the MAPA-2) allowing derivation of these findings included a representative sample of 748 children (53% girls) ages 7-14 years tested by 54 speech-language pathologists and audiologists in 27 U.S. states. The authors examined diagnostic accuracy based on the American Speech-Language-Hearing Association (2005) criteria (index test) for confirmed cases of APD. The index was also used to identify listening problems for three other diagnostic categories (LD, ADHD, and SLI). Validated questionnaire responses from parents and school personnel allowed incorporation of functional measures widely supported in APD diagnosis but unavailable with other normative and sensitivity/specificity studies. Results Reliability and validity were both satisfactory, and diagnostic accuracy for an APD group of 18 (28% female) compared to the remaining typical group of 625 yielded 89% sensitivity and 82% specificity. The remaining three groups (LD, ADHD, and SLI), where comorbidity was expected to be about 50%, had APD-type listening problems with a prevalence ranging from 52% to 65%. Conclusions Current results provide important evidence for the construct of APD. The MAPA-2 can be administered by an audiologist or speech-language pathologist. A similar diagnostic protocol in Australia yielded positive therapeutic gains. Further study is encouraged to determine if the present positive findings will be found in future research.

On differentiating auditory processing disorder (APD) from attention deficit disorder (ADD): an illustrative example using the Cattell-Horn-Carroll (CHC) model of cognitive abilities

Objective: To clarify the distinction between Auditory Processing Disorder (APD) and Attention Deficit Disorder (ADD) using the CHC Model.Design: A cross-sectional study compared responses of caregivers about their children's behaviour to identify characteristics of APD (CHC Model) and ADD (DSM-5).Study Sample: Caregivers, mostly mothers (92%), of 149 children (M 61%; F 39%) aged from 6 to 16 years, referred for "Auditory Processing Assessment" of their child, were shown an A4 card displaying the characteristics of AP from the CHC Model on one side, and of ADD from DSM-5 on the other. Both sides were untitled. For each side, caregivers were asked if the characteristics were true of their child using a Conners-type four-point scale.Results: The majority of children were rated by caregivers as displaying characteristics of ADD, rather than an APD problem. Comparing problems with AP vs. problems with ADD gave: Wilcoxon T = 9.71; z = 4.86, p < 0.001.Conclusion: The finding that most children referred for an AP Assessment showed characteristics of ADD was surprising. Given the continuing audiological controversies about the nature of AP and about differentiating AP disorders from ADD, the CHC Model offers a different and informative perspective.