Single-session gamma sensory stimulation entrains real-time electroencephalography but does not enhance perception, attention, short-term memory, or long-term memory

Journal of Alzheimer s Disease Reports, Journal Year: 2025, Volume and Issue: 9

Published: Jan. 1, 2025

Studies have shown that gamma (40 Hz) audiovisual stimulation can enhance oscillations and improve cognitive functioning in patients with Alzheimer's disease. However, despite promising long-term results, the efficacy of short-duration or single-session 40 Hz entrainment humans has been questioned by behavioral studies fail to find observable aftereffects, for two possible reasons: 1) lack validated entrainment, as most lacked concurrent electroencephalography (EEG) data verify neural did take place, 2) diverse tests, not test a wide range factors. This study aimed increase sensitivity detecting entrainment. We employed mid- post-stimulation EEG monitoring ensure worked, comprehensive battery probes perception, attention, working memory, memory. Participants received 30 min synchronized light sound stimulation, followed visual perceptual task, attentional network change detection memory picture EEG. observed robust during but no significant oscillation after improvements. Despite online sensory requires consistent exposure induce neurological changes. Future research should determine optimal duration frequency maximize its therapeutic potential.

Language: Английский

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Re-evaluating the choice of gamma stimulation frequency for the potential treatment of Alzheimer’s disease: Novel invisible spectral flicker evokes gamma responses at various frequencies

PLoS ONE, Journal Year: 2025, Volume and Issue: 20(5), P. e0321633 - e0321633

Published: May 20, 2025

With recent advances in the potential usage of visual gamma stimulation at 40 Hz for treatment Alzheimer’s disease, there is motivation to evaluate adjacent frequencies ensure that specifically optimal. As with luminance flicker may affect adherence clinical trials due its inherent perceived flickering, invisible spectral (ISF) was proposed as a more comfortable alternative entraining Hz. Based on current understanding mechanism action stimulation, exact frequency debatable. This study investigates ability ISF evoke acute responses several range 36–44 Twenty healthy volunteers were included an electroencephalography (EEG) experiment nine different (36–44 Hz, 1 interval). Estimated signal-to-noise ratios (SNR) showed cortical power significantly increased all compared baseline, but no significant difference SNR between frequencies. There subject effect, suggesting higher variability subjects than alone. Our results indicate can steady-state potentials low Across population participants, preference or trend any specific tested found. While subject-stimulus interaction significant, it described little variance and patterns individual frequency.

Language: Английский

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Invisible multi-luminaire 40 Hz flicker does not entrain human electroencephalography

Journal of Alzheimer s Disease, Journal Year: 2025, Volume and Issue: unknown

Published: May 21, 2025

Background Multi-luminaire light stimulation is a novel technique based on luminance flicker with low modulation depth created by two spatially adjacent sources aimed to deliver 40 Hz neural while reducing discomfort, offering potential non-pharmacological, noninvasive, and in-home interventions for Alzheimer's disease dementia. However, these cognitive effects have never been validated electroencephalography (EEG). Objective In this study we aim assess the ability of multi-luminaire evoke EEG response under conditions: direct viewing indirect viewing. Methods The M + BrainCare Delta Electronics was used in study. Participants were stimulated either directly looking at (direct condition), or off reflection from piece paper mimic everyday reading (indirect condition). power conditions compared positive control 100% (stroboscopic flicker). Results both conditions, there no significant oscillations. contrast, stroboscopic elicited robust entrainment all participants, propagating frontal regions. Conclusions Our results question efficacy technology, specifically light, evoking responses. Future studies involving technology should pay special attention validation prior making claims about oscillation brain health.

Language: Английский

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Re-evaluating the choice of gamma stimulation frequency for the potential treatment of Alzheimer’s disease

Research Square (Research Square), Journal Year: 2024, Volume and Issue: unknown

Published: June 4, 2024

With recent advances in the potential usage of visual gamma stimulation at 40 Hz for treatment Alzheimer’s disease, there is motivation to evaluate adjacent frequencies ensure that specifically optimal.The choice based on studies over several decades describe "40 Hz" oscillations with considerable frequency variability.As luminance flicker may affect adherence clinical trials due its inherent perceived flickering, invisible spectral (ISF) was proposed as a more comfortable alternative entraining Hz. This study investigates ability ISF evoke acute responses range 36-44 Twenty healthy volunteers were included an electroencephalography (EEG) experiment initial eyes-open baseline recording followed by paradigm using nine different (36-44 Hz, 1 interval). The evaluated signal-to-noise ratio (SNR) averaged occipital electrodes and analysed mixed-effect models. Evoked compared between frequencies. estimated SNR values showed EEG power significantly increased all baseline, but no significant difference There subject effect, even when disregarding one who responded 1-2 orders magnitude higher than others. These results suggest variability subjects alone. Our indicate can induce steady-state visually evoked potentials low Across population participants, preference or trend any specific tested found. While subject-stimulus interaction significant, it described little variance patterns individual frequency.

Language: Английский

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