In this studies it showed how different light wavelength affect on different part of brain region . It exposure to certain monochromatic wavelengths can affect non-visual brain regions. This research indicates that using light can have a positive impact on health-related problems such as spring asthenia, circadian rhythm disruption, and even bipolar disorders and Alzheimer’s. It also support when apply syntonic light therapy has to be under supervision, just cant simply apply. 

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