arousal threshold
The minimum stimulus intensity required to cause awakening or arousal from sleep.
Full Definition
Arousal threshold refers to the level of sensory or physiological stimulation necessary to trigger an arousal response or awakening from sleep. This threshold varies significantly between sleep stages, being highest during slow-wave sleep and lowest during REM sleep and stage 1 sleep. Individual arousal thresholds can be influenced by factors such as age, medications, sleep deprivation, and underlying sleep disorders. In sleep medicine, understanding arousal thresholds helps explain why some patients with sleep apnea have frequent arousals while others with similar severity do not, affecting treatment approaches.
Usage
Usage note: Refers to the stimulus level needed, not the frequency of arousals (which is 'arousal index').
In Context
- "Patients with low arousal thresholds may experience fragmented sleep despite minimal respiratory events." — Sleep study interpretation
- "The arousal threshold appears elevated in this patient, explaining the absence of cortical arousals despite significant oxygen desaturations." — Clinical assessment