Hearing Impairment in the Extended High Frequencies in Children Despite Clinically Normal Hearing

Abstract

Objectives: Pediatric hearing impairment, regardless of degree and type, has a detrimental effect on speech perception, cognition, oral language development, academic outcomes, and literacy. Hearing assessment in the clinic is limited to 8 kHz although humans can hear up to 20 kHz. Hearing impairment in the extended high frequencies (EHFs > 8 kHz) can occur despite clinically normal hearing. However, to date, the nature and effects of EHF hearing impairment in children remain unknown. The goals of the present study were to determine the effects of EHF hearing impairment on speech-in-noise recognition in children and to examine whether hearing impairment in the EHFs is associated with altered cochlear functioning in the standard frequencies.Design: A volunteer sample of 542 participants (4 to 19 years) with clinically normal audiograms were tested. Participants identified with EHF impairment were assigned as cases in a subsequent case-control study. EHF loss was defined as hearing thresholds greater than 20 dB in at least one EHFs (10, 12.5, or 16 kHz). Speech recognition thresholds in multi-talker babble were measured using the digit triplet test. Distortion product otoacoustic emissions (f 2 = 2, 3, 4, and 5 kHz) were measured to assess cochlear functioning.Results: Thresholds in the EHFs were as reliable as those in the standard frequency range. Thirty-eight children had EHF hearing impairment regardless of a clinically normal audiogram. A linear mixed-effects model revealed that children with EHF hearing impairment had higher (poorer) mean speech recognition threshold than children with normal EHF sensitivity (estimate = 2.14 dB, 95% CI: 1.36 to 3.92; effect size = small). The overall magnitude of distortion product otoacoustic emissions was lower for children with EHF impairment (estimate = -2.47 dB, 95% CI: -4.60 to -0.73; effect size = medium). In addition, the pure-tone average for standard audiometric frequencies was relatively higher for EHF-impaired children (estimate = 3.68 dB, 95% CI: 2.56 to 4.80; effect size = small).Conclusions: Hearing impairment in the EHFs is common in children despite clinically normal hearing and can occur without a history of otitis media. EHF impairment is associated with poorer speech-in-noise recognition and preclinical cochlear deficits in the lower frequencies where hearing thresholds are normal. This study highlights the clinical need to identify EHF impairments in children.

Effects of Stimulus Type on 16-kHz Detection Thresholds

“…For young adults with no evidence of hearing loss, we expected thresholds to cluster around 0 dB HL, and that is approximately the case at 16 kHz for adults. Median thresholds defining 0 dB HL may not be appropriate for children, however, as significant effects of age on EHF sensitivity begin at or below 10 years of age (Trehub et al 1988; Buren et al 1992; Hemmingsen et al 2021; Mishra et al 2022b). This has prompted some researchers to suggest development of a separate set of HL values for younger listeners (Hemmingsen et al 2021).…”

“…Thresholds obtained at the edge of a steeply sloping hearing loss can be lower for FM tones than pulsed tones or steady tones, and this effect may be more common at EHFs than the standard audiometric range, due to the greater prevalence of hearing loss at EHFs. While EHF sensitivity is typically better in younger than older listeners, as many as 7% of school-age children and 18% of young adults with hearing thresholds ≤20 dB HL between 250 and 8000 Hz have at least one threshold >20 dB HL between 10 and 16 kHz (Mishra et al 2022a,b). The a priori prediction was that children might have an easier time attending to dynamic stimuli (pulsed and FM tones) and therefore might have lower thresholds for dynamic stimuli than for steady tones at both 8 and 16 kHz.…”

“…Differential effects of age across frequency have been documented in previous studies (Trehub et al 1988; Rodriguez Valiente et al 2014). Whereas maturation of attention tends to improve a listener’s ability to make use of sensory input (Haapaniemi 1996), aging effects that are evident by 10 years of age (Buren et al 1992; Hemmingsen et al 2021; Mishra et al 2022b) reduce the quality of sensory cues available at EHFs. Also consistent with previous literature (Frank 2001; Rodriguez Valiente et al 2014), thresholds were more variable across participants at 16 kHz than 8 kHz.…”

“…More recently, however, several groups have shown that hearing loss at EHFs significantly reduces masked speech recognition (Monson et al 2019; Trine & Monson 2020; Saxena et al 2022). For example, Mishra et al (2022a,b) reported that recognition of digits in a six-talker babble is poorer for children and adults with elevated thresholds at one or more EHFs between 10 and 16 kHz than for listeners with normal EHF sensitivity. Effects of EHF audibility may be most evident when the masker is low-pass filtered at 8 kHz (Motlagh-Zadeh et al 2019; Polspoel et al 2022) or when EHF content of the masker is reduced by rotating the masker talker’s head away from the listener (Monson et al 2019; Flaherty et al 2021).…”

Brainstem Auditory Physiology in Children with Listening Difficulties

“…Evidence has accumulated from recent reports that EHF hearing is related to speech in noise SRT (Flaherty, Libert, & Monson, 2021; Motlagh Zadeh et al, 2019; Polspoel, Kramer, van Dijk, & Smits, 2021) and to a range of physiologic measures in the standard frequency range. EHF is also an important early marker of peripheral auditory damage (Blankenship et al, 2021; Hunter, Monson, et al, 2020; Mishra, Saxena, & Rodrigo, 2022; Motlagh Zadeh et al, 2019).…”