Brain waves are a great indicator to evaluate brain activities. Both Alpha waves and Beta waves are seen in wakefulness. The former is observed where there is flowing of thoughts, mental coordination and mind/body integration whereas the latter in fast-and-complex activity, anxiety and complex thought where concentration and mental focus are difficult to be achieved. Therefore, high ratio of Alpha to Beta brain waves is associated with feelings of relaxation and effortless mental clarity and focus.
Measuring the level of chromogranin A (CgA) in saliva is a very useful way to gauge mental stress. CgA is an acidic protein that is released from the adrenal gland when a person is experiencing stressful situations. Clinical studies have demonstrated salivary measurements of CgA is a reliable index for acute psychological stress.