Gamma sensory stimulation and effects on the brain

Abstract

Findings by the Tsai lab and others1–8demonstrate that 40 Hz frequency sensory stimulation induces electrophysiological responses and attenuates pathology in mouse models of Alzheimer’s disease (AD). A recent study inNature Neurosciene9concluded that the stimulation does not affect endogenous gamma oscillations or amyloid burden. We welcome research investigating 40 Hz sensory stimulation, and the article by Soula et al enhances our understanding of the brain’s electrophysiological response to 40Hz. However, we respectfully suggest that the data in Soula et al are consistent with a neuronal response to 40 Hz, which we further support with new data in humans. Moreover we contend the non-significant effects on amyloid are due to technical limitations of the study.

Audiovisual gamma stimulation for the treatment of neurodegeneration

“…In mice, visual stimulation evokes a strong intracranial 40 Hz LFP response in the visual cortex [7,9,59] and, according to one study, also in other cortical areas [9]. Interestingly, recent studies suggest that 40 Hz sensory stimulation may not engage the same circuitry that generates endogenous gamma oscillations but rather induce externally driven gamma activity [59,62,63]. In the hippocampus, three studies reported a significant increase in LFP 40 Hz power response [7,9,64], whereas one study did not [59].…”