Dichotic listening is associated with phonological awareness in Australian aboriginal children with otitis media: A remote community-based study

Phonological awareness and reading outcomes in children with a history of otitis media: a review

OBJECTIVE

A review was conducted to investigate the current evidence for effects of otitis media (OM) on phonological awareness and reading skills in children under 12 years old.

DESIGN

A review conducted in 2024 to identify articles between 1978 and 2024 related to OM and its impact on (pre-)reading skills.

STUDY SAMPLE

An initial search across six databases provided 6808 research outputs. After screening, 27 articles were retained. Screening of the references on the selected articles provided an additional 6, giving 33 articles in the final review.

RESULTS

The selected research papers did not all evaluate the same phonological awareness or reading skills. Of the studies, 20 identified that a history of OM impacted reading outcomes. Twelve studies found no significant impact while one study showed an impact which resolved with time.

CONCLUSION

The findings do not show a consistent association between a history of OM and phonological processing or reading skills. This is likely due to the wide range of methodologies employed and variability in the focus of the respective studies. Future research, including longitudinal studies, would be beneficial to infer the potential impacts of OM on phonological processing or reading skills.

Multiple Sevoflurane Exposures During the Neonatal Period Cause Hearing Impairment and Loss of Hair Cell Ribbon Synapses in Adult Mice

Objectives

This study aims to investigate the effects of multiple sevoflurane exposures in neonatal mice on hearing function in the later life and explores the underlying mechanisms and protective strategies.

Materials and Methods

Neonatal Kunming mice were exposed to sevoflurane for 3 days. Auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) tests, immunofluorescence, patch-clamp recording, and quantitative real-time PCR were performed to observe hearing function, hair cells, ribbon synapses, nerve fibers, spiral ganglion neurons, and oxidative stress.

Results

Compared to control group, multiple sevoflurane exposures during the neonatal time significantly elevated ABR thresholds at 8 kHz (35.42 ± 1.57 vs. 41.76 ± 1.97 dB, P = 0.0256), 16 kHz (23.33 ± 1.28 vs. 33.53 ± 2.523 dB, P = 0.0012), 24 kHz (30.00 ± 2.04 vs. 46.76 ± 3.93 dB, P = 0.0024), and 32 kHz (41.25 ± 2.31 vs. 54.41 ± 2.94 dB, P = 0.0028) on P30, caused ribbon synapse loss on P15 (13.10 ± 0.43 vs. 10.78 ± 0.52, P = 0.0039) and P30 (11.24 ± 0.56 vs. 8.50 ± 0.84, P = 0.0141), and degenerated spiral ganglion neuron (SGN) nerve fibers on P30 (110.40 ± 16.23 vs. 55.04 ± 8.13, P = 0.0073). In addition, the V_half of calcium current become more negative (−21.99 ± 0.70 vs. −27.17 ± 0.60 mV, P < 0.0001), exocytosis was reduced (105.40 ± 19.97 vs. 59.79 ± 10.60 fF, P < 0.0001), and Lpo was upregulated (P = 0.0219) in sevoflurane group than those in control group. N-acetylcysteine (NAC) reversed hearing impairment induced by sevoflurane.

Conclusion

The findings suggest that multiple sevoflurane exposures during neonatal time may cause hearing impairment in adult mice. The study also demonstrated that elevated oxidative stress led to ribbon synapses impairment and SGN nerve fibers degeneration, and the interventions of antioxidants alleviated the sevoflurane-induced hearing impairment.