Amplitude Modulation Detection in Children with a History of Temporary Conductive Hearing Loss Remains Impaired for Years After Restoration of Normal Hearing

Variability in auditory processing performance is associated with reading difficulties rather than with history of otitis media

The nature and cause of auditory processing deficits in dyslexic individuals have been debated for decades. Auditory processing deficits were argued to be the first step in a causal chain of difficulties, leading to difficulties in speech perception and thereby phonological processing and literacy difficulties. More recently, it has been argued that auditory processing difficulties may not be causally related to language and literacy difficulties. This study compares two groups who have phonological processing impairments for different reasons: dyslexia and a history of otitis media (OM). We compared their discrimination thresholds and response variability to chronological age- and reading age-matched controls, across three auditory processing tasks: frequency discrimination, rise-time discrimination and speech perception. Dyslexic children showed raised frequency discrimination thresholds in comparison with age-matched controls but did not differ from reading age-matched controls or individuals with a history of OM. There were no group differences on speech perception or rise-time tasks. For the dyslexic children, there was an association between phonological awareness and frequency discrimination response variability, but no association with thresholds. These findings are not consistent with a 'causal chain' explanation but could be accounted for within a multiple deficits view of literacy difficulties.

Early otitis media puts children at risk for later auditory and language deficits

BACKGROUND

Otitis media is a common disorder of early childhood suspected of hindering auditory and language development, but evidence regarding these effects has been contradictory. To examine potential sources of these contradictory past results and explore in more detail the effects of early otitis media on auditory and language development, three specific hypotheses were tested: (1) Variability in children's general attention could influence results, especially for measures of auditory functioning, leading to spurious findings of group differences; (2) Different language skills may be differentially affected, evoking different effects across studies depending on skills assessed; and (3) Different mechanisms might account for the effects of otitis media on acquisition of different language skills, a finding that would affect treatment choices.

METHOD

Children 5-10 years old participated: 49 with and 68 without significant histories of otitis media. The auditory function examined was temporal modulation detection, using games designed to maintain children's attention; two additional measures assessed that attention. Measures of lexical knowledge and phonological sensitivity served as the language measures.

RESULTS

Sustained attention was demonstrated equally across groups of children with and without histories of otitis media. Children with histories of otitis media performed more poorly than peers without those histories on the auditory measure and on both sets of language measures, but effects were stronger for phonological sensitivity than lexical knowledge. Deficits in temporal modulation detection accounted for variability in phonological sensitivity, but not in lexical knowledge.

CONCLUSION

When experimental factors are tightly controlled, evidence emerges showing effects of otitis media early in life on both auditory and language development. Mechanism of effects on language acquisition appear to involve both delayed auditory development and diminished access to the ambient language.

Results of a Novel, Nonsurgical Bone-Conduction Hearing Aid for the Treatment of Conductive Hearing Loss in Australian Children

OBJECTIVE

To determine and compare the benefits a novel adhesive bone-conduction system and a conventional bone-conduction hearing aid (BCHA) on a softband for children with conductive hearing loss.

STUDY DESIGN

Prospective, single-subject randomized, crossover trial.

SETTING

Tertiary referral center in Australia.

PARTICIPANTS

Eight children aged from 4 to 17 years with conductive hearing loss.

INTERVENTION

Rehabilitative with participants using the novel adhesive bone-conduction aid and a BCHA.

MAIN OUTCOME MEASURES

Aided thresholds, as well as speech perception in quiet, unaided and aided with the novel adhesive bone-conduction aid and BCHA on a softband. For the six older children, speech in noise testing was also conducted.

RESULTS

The mean unaided four frequency average hearing levels was 48 dB HL for air conduction, 10.5 dB HL for bone conduction, with a mean air-bone gap in the aided ear of 37.5 dB HL.Four-frequency average hearing level aided thresholds were 20.2 dB for the novel device and 19.8 dB for the BCHA, with no significant difference between the devices. Aided monosyllabic word scores improved from an average of 45% in the unaided condition to 81.6 and 85% for the novel adhesive and BCHA devices, respectively. Aided speech in noise performance improved, on average, by 1.6 dB SNR when wearing the BCHA and the novel adhesive device, with no significant difference in performance between the two devices.

CONCLUSIONS

The novel device provided equivalent performance to the BCHA on all measures and can be considered as an alternative device for pediatric patients with conductive hearing loss.

Tone in Noise Detection in Children with a History of Temporary Conductive Hearing Loss

Children with a history of temporary conductive hearing loss (CHL) during early development may show long-term impairments in auditory processes that persist after restoration of normal audiometric hearing thresholds. Tones in noise provide a simplified paradigm for studying hearing in noise. Prior research has shown that adults with sensorineural hearing loss may alter their listening strategy to use single-channel energy cues for tone-in-noise (TIN) detection rather than rove-resistant envelope or spectral profile cues. Our objective was to determine the effect of early CHL on TIN detection in healthy children compared to controls. Children ages 4-7 years, with and without a history of CHL due to otitis media with effusion (OME) before age 3 years, participated in a two-alternative forced choice TIN detection task. Audiometric thresholds were normal at the time of testing. Thresholds for detection of a 1000 Hz tone were measured in fixed-level noise and in roving-level noise that made single-channel energy cues unreliable. Participants included 23 controls and 23 with a history of OME-related CHL. TIN thresholds decreased with increasing age across participants. Children in both groups showed similar TIN sensitivity and little or no threshold elevation in the roving-level condition compared to fixed-level tracks, consistent with use of rove-resistant cues. In contrast to older listeners with sensorineural hearing loss, there was no detectable change in TIN sensitivity with roving level for children with a history of OME-related CHL.

Auditory processing remains sensitive to environmental experience during adolescence in a rodent model

Elevated neural plasticity during development contributes to dramatic improvements in perceptual, motor, and cognitive skills. However, malleable neural circuits are vulnerable to environmental influences that may disrupt behavioral maturation. While these risks are well-established prior to sexual maturity (i.e., critical periods), the degree of neural vulnerability during adolescence remains uncertain. Here, we induce transient hearing loss (HL) spanning adolescence in gerbils, and ask whether behavioral and neural maturation are disrupted. We find that adolescent HL causes a significant perceptual deficit that can be attributed to degraded auditory cortex processing, as assessed with wireless single neuron recordings and within-session population-level analyses. Finally, auditory cortex brain slices from adolescent HL animals reveal synaptic deficits that are distinct from those typically observed after critical period deprivation. Taken together, these results show that diminished adolescent sensory experience can cause long-lasting behavioral deficits that originate, in part, from a dysfunctional cortical circuit.

Clinical Practice Guideline: Tympanostomy Tubes in Children (Update)

OBJECTIVE

Insertion of tympanostomy tubes is the most common ambulatory surgery performed on children in the United States. Tympanostomy tubes are most often inserted because of persistent middle ear fluid, frequent ear infections, or ear infections that persist after antibiotic therapy. All these conditions are encompassed by the term otitis media (middle ear inflammation). This guideline update provides evidence-based recommendations for patient selection and surgical indications for managing tympanostomy tubes in children. The guideline is intended for any clinician involved in managing children aged 6 months to 12 years with tympanostomy tubes or children being considered for tympanostomy tubes in any care setting as an intervention for otitis media of any type. The target audience includes specialists, primary care clinicians, and allied health professionals.

PURPOSE

The purpose of this clinical practice guideline update is to reassess and update recommendations in the prior guideline from 2013 and to provide clinicians with trustworthy, evidence-based recommendations on patient selection and surgical indications for managing tympanostomy tubes in children. In planning the content of the updated guideline, the guideline update group (GUG) affirmed and included all the original key action statements (KASs), based on external review and GUG assessment of the original recommendations. The guideline update was supplemented with new research evidence and expanded profiles that addressed quality improvement and implementation issues. The group also discussed and prioritized the need for new recommendations based on gaps in the initial guideline or new evidence that would warrant and support KASs. The GUG further sought to bring greater coherence to the guideline recommendations by displaying relationships in a new flowchart to facilitate clinical decision making. Last, knowledge gaps were identified to guide future research.

METHODS

In developing this update, the methods outlined in the American Academy of Otolaryngology-Head and Neck Surgery Foundation's "Clinical Practice Guideline Development Manual, Third Edition: A Quality-Driven Approach for Translating Evidence Into Action" were followed explicitly. The GUG was convened with representation from the disciplines of otolaryngology-head and neck surgery, otology, pediatrics, audiology, anesthesiology, family medicine, advanced practice nursing, speech-language pathology, and consumer advocacy.

ACTION STATEMENTS

The GUG made strong recommendations for the following KASs: (14) clinicians should prescribe topical antibiotic ear drops only, without oral antibiotics, for children with uncomplicated acute tympanostomy tube otorrhea; (16) the surgeon or designee should examine the ears of a child within 3 months of tympanostomy tube insertion AND should educate families regarding the need for routine, periodic follow-up to examine the ears until the tubes extrude.The GUG made recommendations for the following KASs: (1) clinicians should not perform tympanostomy tube insertion in children with a single episode of otitis media with effusion (OME) of less than 3 months' duration, from the date of onset (if known) or from the date of diagnosis (if onset is unknown); (2) clinicians should obtain a hearing evaluation if OME persists for 3 months or longer OR prior to surgery when a child becomes a candidate for tympanostomy tube insertion; (3) clinicians should offer bilateral tympanostomy tube insertion to children with bilateral OME for 3 months or longer AND documented hearing difficulties; (5) clinicians should reevaluate, at 3- to 6-month intervals, children with chronic OME who do not receive tympanostomy tubes, until the effusion is no longer present, significant hearing loss is detected, or structural abnormalities of the tympanic membrane or middle ear are suspected; (6) clinicians should not perform tympanostomy tube insertion in children with recurrent acute otitis media who do not have middle ear effusion in either ear at the time of assessment for tube candidacy; (7) clinicians should offer bilateral tympanostomy tube insertion in children with recurrent acute otitis media who have unilateral or bilateral middle ear effusion at the time of assessment for tube candidacy; (8) clinicians should determine if a child with recurrent acute otitis media or with OME of any duration is at increased risk for speech, language, or learning problems from otitis media because of baseline sensory, physical, cognitive, or behavioral factors; (10) the clinician should not place long-term tubes as initial surgery for children who meet criteria for tube insertion unless there is a specific reason based on an anticipated need for prolonged middle ear ventilation beyond that of a short-term tube; (12) in the perioperative period, clinicians should educate caregivers of children with tympanostomy tubes regarding the expected duration of tube function, recommended follow-up schedule, and detection of complications; (13) clinicians should not routinely prescribe postoperative antibiotic ear drops after tympanostomy tube placement; (15) clinicians should not encourage routine, prophylactic water precautions (use of earplugs or headbands, avoidance of swimming or water sports) for children with tympanostomy tubes.The GUG offered the following KASs as options: (4) clinicians may perform tympanostomy tube insertion in children with unilateral or bilateral OME for 3 months or longer (chronic OME) AND symptoms that are likely attributable, all or in part, to OME that include, but are not limited to, balance (vestibular) problems, poor school performance, behavioral problems, ear discomfort, or reduced quality of life; (9) clinicians may perform tympanostomy tube insertion in at-risk children with unilateral or bilateral OME that is likely to persist as reflected by a type B (flat) tympanogram or a documented effusion for 3 months or longer; (11) clinicians may perform adenoidectomy as an adjunct to tympanostomy tube insertion for children with symptoms directly related to the adenoids (adenoid infection or nasal obstruction) OR in children aged 4 years or older to potentially reduce future incidence of recurrent otitis media or the need for repeat tube insertion.

Monaural and binaural phase sensitivity in school-age children with early-childhood otitis media

OBJECTIVE

Previous research has linked recurrent otitis media (OM) during early childhood to reduced binaural masking level differences (BMLDs) in school-age children. How this finding relates to monaural processing abilities and the individual otologic history has not been investigated systematically. The current study, therefore, addressed these issues.

DESIGN

Sensitivity to monaural and binaural phase information was assessed using a common test paradigm. To evaluate the influence of the otologic history, overall OM duration, OM onset age, and the time since the last OM episode were considered in the analyses.

STUDY SAMPLE

Children aged 6-13 years with a history of recurrent OM (N = 42) or without any previous ear diseases (N = 20).

RESULTS

Compared to the controls, the OM children showed smaller BMLDs (p < 0.05) whereas their monaural and binaural detection thresholds were comparable (p > 0.05). After controlling for age, the otologic history factors failed to predict the BMLDs of the OM children. Their monaural detection thresholds were correlated with the binaural detection thresholds (r = ∼0.5, p < 0.05) but not the BMLDs.

CONCLUSIONS

The current study suggests that early-childhood OM can impair binaural processing abilities in school-age children.

Preserving Inhibition during Developmental Hearing Loss Rescues Auditory Learning and Perception

Transient periods of childhood hearing loss can induce deficits in aural communication that persist long after auditory thresholds have returned to normal, reflecting long-lasting impairments to the auditory CNS. Here, we asked whether these behavioral deficits could be reversed by treating one of the central impairments: reduction of inhibitory strength. Male and female gerbils received bilateral earplugs to induce a mild, reversible hearing loss during the critical period of auditory cortex development. After earplug removal and the return of normal auditory thresholds, we trained and tested animals on an amplitude modulation detection task. Transient developmental hearing loss induced both learning and perceptual deficits, which were entirely corrected by treatment with a selective GABA reuptake inhibitor (SGRI). To explore the mechanistic basis for these behavioral findings, we recorded the amplitudes of GABA_A and GABA_B receptor-mediated IPSPs in auditory cortical and thalamic brain slices. In hearing loss-reared animals, cortical IPSP amplitudes were significantly reduced within a few days of hearing loss onset, and this reduction persisted into adulthood. SGRI treatment during the critical period prevented the hearing loss-induced reduction of IPSP amplitudes; but when administered after the critical period, it only restored GABA_B receptor-mediated IPSP amplitudes. These effects were driven, in part, by the ability of SGRI to upregulate α1 subunit-dependent GABA_A responses. Similarly, SGRI prevented the hearing loss-induced reduction of GABA_A and GABA_B IPSPs in the ventral nucleus of the medial geniculate body. Thus, by maintaining, or subsequently rescuing, GABAergic transmission in the central auditory thalamocortical pathway, some perceptual and cognitive deficits induced by developmental hearing loss can be prevented.SIGNIFICANCE STATEMENT Even a temporary period of childhood hearing loss can induce communication deficits that persist long after auditory thresholds return to normal. These deficits may arise from long-lasting central impairments, including the loss of synaptic inhibition. Here, we asked whether hearing loss-induced behavioral deficits could be reversed by reinstating normal inhibitory strength. Gerbils reared with transient hearing loss displayed both learning and perceptual deficits. However, when animals were treated with a selective GABA reuptake inhibitor during or after hearing loss, behavioral deficits were entirely corrected. This behavioral recovery was correlated with the return of normal thalamic and cortical inhibitory function. Thus, some perceptual and cognitive deficits induced by developmental hearing loss were prevented with a treatment that rescues a central synaptic property.