The definition is abnormal behavior is challenging because perspectives of abnormal behavior have changed over time. However, abnormal behavior is defined as behavior that is socially unacceptable, maladaptive, distressing or leads to distorted thoughts. There are four important markers used define abnormal behavior. The first marker is if the behavior violates social norms. If an exhibited behavior goes against what a society considers normal, it becomes abnormal. The second marker of abnormal behavior is statistical rarity. People with behavior that are rare in the population are considered abnormal. The third marker is personal distress. If a behavior causes distress to an individual such as the case of obsessive compulsive disorder, it is classified as abnormal (Basset & Baker, 2015) People may struggle to differentiate from what is normal and abnormal behavior because behaviors vary within cultures. What is accepted as normal in one culture may be abnormal in another.

Recent research on the causes of abnormal behavior has changed my perspective on how I view and treat abnormal behavior. Initially, abnormal behavior was associated with demon possession as shown by the Salem witch trials (Comer, 2014). Use of diagnostic categories founded on symptoms and considering behavior in terms of how a person function have impacted my thinking over time.