Salivary Alpha-Amylase Reactivity under Psycho-Physiological Stress. A Nonverbal Communication Measurement Tool?

Previous studies have shown that changes in salivary alpha-amylase (sAA) levels are dependent on psychosocial stress stimulation and reflect the activity of the sympathetic nervous system. sAA measurement can be performed easily and quickly; therefore, it may be useful for evaluating psychosocial or physical stress. The aim of this preliminary study was to examine the use of sAA measurements as objective indicators of psychosocial and/or physical stress levels by examining sAA changes in volunteers subjected to conditions similar to those suffered by children with severe motor and intellectual disabilities and cerebral paralysis. Twelve healthy volunteers were required to not move or speak, as is found in patients suffering from total paralysis, for 30 min. Saliva samples were taken at three points, and sAA activity was measured using a hand-held monitor before the test, immediately after the test, and 10 min after the test. In the present study, a marked increase in sAA activity due to physiological stress and a rapid return to the baseline level were observed. Many subjects felt body pain and mental distress. This measurement method is useful for evaluating stress in children with severe motor and intellectual disabilities, who can not fully express their emotions or communicate with their caregivers.