has part has part characteristic of has modifier Atypical behavior Atypical behaviors should include or directly affect observable actions. While behavioral disorders often encompass abnormal thoughts, feelings, perceptions, or other cognitions, these alone would not be considered atypical behavioral features. Atypical behavior is an abnormality in a person's actions that can be controlled or modulated by the will of the individual. While abnormal behaviors can be difficult to control, they are distinct from other abnormal actions that cannot be affected by the individual's will. Abnormality of mental function behavior process abnormal process quality