In point of fact, many stimuli are beneath the " threshold " of a man's consciousness.
The threshold-value of the stimuli adequate for the various senses may be extraordinarily lowered.
By the rules of induction from concomitant variations, we are logically bound to infer the realistic conclusion that outer physical stimuli cause inner sensations of sensible effects.
Breath holding spells are episodes of brief, involuntary cessations of breathing that occur in children in response to stimuli such as anger, frustration, fear, or injury.
Most children with these disorders seem to have a biological vulnerability to stress, making them more susceptible to environmental stimuli than the rest of the population.