What is the psychological impact of an abrupt, instantaneous drop from full daylight to zero ambient light?

Answer

It triggers an immediate, high-alert response

Human perception is calibrated to a baseline ambient light level; therefore, an immediate plunge to zero light triggers a high-alert response in the brain, which can intensify the memory of the event.

What is the psychological impact of an abrupt, instantaneous drop from full daylight to zero ambient light?
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