Hearing Health Update - October 2019

AUDITORY PROCESSING DISORDER RESEARCH ACCOMPLISHMENTS

Thanks to the generosity of General Grand Chapter Royal Arch Masons International, Hearing Health Foundation (HHF) funds groundbreaking research to advance our scientific understanding of Auditory Processing Disorder (APD).

Grants focused on APD are awarded annually to promising scientific investigators through the Emerging Research Grants (ERG) program.

AUDITORY PROCESSING DISORDER RESEARCH

ACCOMPLISHMENTS BY HHF- FUNDED SCIENTISTS

Samira Anderson, Au.D., Ph.D., and her colleagues’ research found that amplification may improve neural representation of the speech signal in new hearing aid users. The improvement with amplification was also found in cortex, and, in particular, decreased P1 latencies and lower N1 amplitudes may indicate greater neural efficiency. Learn more.

Inyong Choi, Ph.D., and team found that how well you combine information across multiple frequencies is a critical factor for good speech-in-noise understanding. Dr. Choi and colleagues are now studying how to improve the sensitivity to this "naturalness" in listeners with hearing loss and is expecting to provide individualized therapeutic options to address the difficulties in speech-in- noise understanding. Learn more.

Beula Magimairaj, Ph.D., has presented a novel framework for conceptualizing auditory processing abilities in school-age children. According to her framework, cognitive and linguistic factors are included along with auditory factors as potential sources of deficits that may contribute individually or in combination to cause listening difficulties in children. Learn more.
Watch Dr. Magimairaj's recorded report to the South Central Conference. (Click Here)

Srikanta Mishra, Ph.D., and team successfully demonstrate the effectiveness of the automated noise rejection procedure of sweep-tone–evoked stimulus frequency otoacoustic emissions (SFOAEs )in adults. The results should be useful for developing tests for cochlear function that can be useful in the clinic and laboratory. Learn more.

Nirmal Kumar Srinivasan, Ph.D., and colleagues’ work suggests sharp binaural pitch fusion is necessary for maximal speech perception in noise when acoustic hearing is available to transmit voice pitch cues. Speech reception thresholds measured using male and female target talkers were compared with binaural pitch fusion results to complete the study. Learn more.

Richard A. Felix, II, Ph.D., produced evidence that lower-level subcortical areas may play a significant role in hearing disorders. Subcortical pathways represent early-stage processing on which sound perception is built; therefore problems with understanding complex sounds such as speech often have neural correlates of dysfunction in the auditory brainstem, midbrain, and thalamus. Learn more.

Yoojin Chung, Ph.D., looked at the neural mechanisms underlying the limitations of clinical bilateral CIs as they relate to understanding conversations in noise and suggested improvements, such as delivering ITD information in low- rate pulse trains. Learn more.

Elizabeth McCullagh, Ph.D., performed the first study that explored alterations in glycinergic inhibition in the auditory brainstem of FXS mice. Given the findings in this study, further knowledge of the alterations in the lower auditory areas, such as the tonotopic differences in inhibition to the MNTB, may be necessary to better understand the altered sound processing found in those with FXS. Learn more.

Andrew Dimitrijevic, Ph.D., was published for his study that measured alpha rhythms during attentive listening in a commonly used speech-in-noise task, known as digits-in-nose (DiN), to better understand the neural processes associated with speech hearing in noise. Dimitrijevic and his colleagues’ novel findings propel the field’s understanding of the neural activity related to speech-in-noise tasks. Learn more.