A personality trait disturbance characterized by childish emotional and behavior patterns.Immature personalities are found at every age. Typically these individuals have little control over their emotions, shifting from laughter to tears or from friendliness to hostility in a matter of minutes. When faced with frustrations and decisions, they are likely either to “fold up” or react impulsively and unthinkingly. They cannot tolerate pressure of any kind and tend to panic in an emergency.