Alzheimer’s patients can present with impairments in brain waves, specifically in gamma-frequency oscillations in the range of 25–80 Hz, that are important for attention, perception, and memory.
In 2016, Iaccarino et al demonstrated that visual stimuli presented at 40 Hz, but not other frequencies reduced levels of beta-amyloid plaques in mice; beta-amyloid plaques are a pathogenic marker for Alzheimer Disease. However, the results were limited to the visual cortex.
In their new study published in Cell, the researchers (Martorell et al, 2019) examined the application of a 10 kHz tone presented at 40 Hz rate for 1 hour per day for 7 days in mice. They found that the treatment drove gamma frequency neural activation not only in the auditory cortex but also in the hippocampus. This also resulted in reduced beta-amyloid plaques and improved spatial and recognition memory. Further, combined auditory and visual stimulation decreased amyloid in the medial prefrontal cortex, which was not observed in single stimuli conditions.
Though in an early study, the application of sound therapies for Alzheimer Disease represents an intriguing treatment pathway. For more information see the full article.
Iaccarino et al. (2016) Gamma frequency entrainment attenuates amyloid load and modifies microglia. Nature 540 (7632):230–235.
Martorell et al. (2019) Multi-sensory gamma stimulation ameliorates Alzheimer’s-Associated Pathology and Improves Cognition. Cell 177:1–16.
In a recent study, Mahendran and colleagues (2021) sought to compare the rates of cochlear implant (CI) referral and implantation across different races and to compare audiometric profiles of the patients via retrospective analysis. Demographic and audiometric data were collected for 504 patients between 2010–2020 who underwent CI evaluation or implantation. Of those, 388 met…
Should we provide cochlear implants earlier for children with large vestibular aqueduct syndrome? Patterson and colleagues (2021) examined outcomes of nine pediatric patients with Pendred syndrome who received cochlear implants between 2003–2017. Pendred syndrome is an autosomal recessive disorder defined by the combination of sensorineural hearing loss, goiter and an enlarged vestibular aqueduct (EVA). All…
Cochlear implantation is generally considered a safe and effective recommendation for healthy adults who have bilateral, moderate-to-severe or moderate-to-profound sensorineural hearing loss and do not benefit from acoustic amplification (i.e., poor speech recognition). However, given the large elderly population and the importance of timely hearing intervention, there is a need to more closely examine the…