Chapter 25Specific Illnesses, Ailments and Other Physical Problems · Head Cold

What you describe [a “loaded” head with sluggish thinking and mechanical thoughts] happens very usually during a cold in the head, as ordinarily one depends upon the brain cells for the transmission of the mental thought. When the mind is not so dependent on the brain cells, then their obscuration by the cold does not interfere with clear seeing and thinking and one is not thrown back in the mechanical mind.