Currently I am experimenting with 40 Hz cranial photobiomodulation using an 880 nm wavelength, which can penetrate the skull and into a few cm into the brain.
I have modified a commercial red light therapy cap by adding my own waveform-modulated power supply. This enables me to increase the power to the LEDs and modulate them with various waveforms and frequencies. Currently I am pulsing the LEDs with a 40 Hz square wave with a 20% duty cycle. The 20% duty cycle lets me apply more power to the LEDs without burning them up.
I have been using the cap every other night for 30 minutes. There is definitely a subjective result. I feel this has put the finishing touches on my quest to eliminate age-related brain fog.
It also is improving my short-term working memory, which is another thing we lose as we age.
(These caps and helmets are typically sold to reverse hair loss.)
One way that I see benefits is in my ability to complete crosswords and sudoku puzzles. The percentage of NYT crosswords I can complete has risen since I have started the 880 nm photobiomodulation.
I plan to try other frequencies, but I don’t see much room for improvement.
“transcranial photobiomodulation with an 808 nm pulsed NIR laser (transcranial: 100 mW/cm2; intranasal: 25 mW/cm2: 40 Hz for 20 min) was recently reported to reduce neuronal damage in the prefrontal cortex and γ-aminobutyrinergic (GABAergic) neurons in the hippocampus, protect the integrity of the perihippocampal inhibitory network composed of parvalbumin-positive neurons, and maintain the normal hippocampal γ band rhythm [43].”
40Hz modulation is associated with gamma brain waves, which are known to be around 30-100 Hz, with 40Hz being within that range. There’s some research suggesting that stimulating gamma waves can have beneficial effects on brain function, particularly in conditions like Alzheimer’s disease.
However, a subsequent replicating study challenged these findings (99). Another study found that 10 Hz of PBM was more effective than 40 Hz in activating M2 microglia and clearing Aβ plaques (100). This suggests a reconsideration of whether 40 Hz is best for performing these functions or whether a combination of these or other frequencies would be better. This is further critically analyzed in a later section on Aberrated Brain Waveforms Expression, Gamma, and on proposed PBM parameter settings in Considerations for PBM parameters to Maximize Potential Outcomes for Alzheimer’s, Pulse rate of 40 Hz, 10 Hz and 0 Hz (continuous).
Studies propose that PBM could directly or indirectly affect the aggregation state of Aβ. Direct irradiation with red light that been observed to reduce Aβ aggregation (101). It has been suggested that a photoelectric coupling effect alters protein structures, diminishing Aβ aggregation and toxicity, and that NIR light is capable of disassembling Aβ in vivo (102)."
