Randall's episodes are most likely a feature of a rare class of disorders called dissociative disorders. Dissociative disorders are a class of disorders in which people lose contact with portions of their consciousness or memory, resulting in disruptions in their sense of identity.

There are many aspects of speech that could indicate a person is a psychopath. A combination of psychological and linguistic research has pointed to several factors that indicate psychopathology. The excess use of causatives in sentences are indicative of a psychopath's need to create a logical justification for their acts. The use of the past tense instead of present indicates a psychological detachment from the world as if they are looking in instead of a participant. Psychological factors such as a lack of remorse or an obsession with basic needs also point to psychopathy. 

While borderline personality disorder (BPD) does not have the highest suicide rate of any psychological disorder, it has the highest of the personality class. Some reports estimate that up to 10% of diagnosed patients carry through with suicide. The exact number depends on the study, but BPD holds the highest rate under any account.

Exact known causes of Parkinson's disease are still unknown, but researchers are working towards a better understanding. On the other hand, a gene on chromosome 4 has been identified to cause Huntington's, and a thiamine deficiency has been identified to cause Wernicke-Korsakoff syndrome. These reductionist explanations suggest that Huntington's and Wernicke-Korsakoff syndrome are caused by singular processes, but it is probably much more complex.

Cognitive theorists believe that the mind and patterns of thinking are largely in control of how a person views and responds to life's events. Cognitive theorists believe that people with unipolar depression persistently view events and situations in life in negative ways. As a result of these defeatist perceptions, such people sink into feelings of gloom, helplessness, and depression.

Any traumatic event can trigger post-traumatic stress disorder. Some of the most likely to do so include combat, disasters, abuse of any kind, victimization, and torture.

Psychodynamic theorists are very firm in their belief about the interactions between the id and ego during the early, formative years of a person's life. They propose that there is a battle between anxiety-provoking id impulses and anxiety-reducing defense mechanisms.

The diathesis-stress model states that disorders are caused by both a predisposition to the disorder and a life stress that serves as a trigger. The only example that follows that pattern is Thomas's family history (diathesis) and stressful life events (trauma). 

The psychodynamic approach in psychology holds that internal drives for pleasure (the id) is in constant conflict with the rational mind (the ego) and the moral mind (the superego). When these forces are unbalanced, they can manifest themselves as a variety of mental disorders.