Schizotypal personality disorder affects about 3% of the population. It can be a precursor for Schizophrenia but often has a stable course and can be diagnosed by the symptoms provided in the question. Schizotypal personality disorder can be confused with schizophrenia. The main difference between the two disorders is that people with schizotypal personalities may experience brief psychotic episodes accompanied by delusions or hallucinations; however, these delusional episodes are not as frequent, prolonged, or intense as the psychosis experienced by individuals with schizophrenia.

Personality disorders are not typically diagnosed until age 18. Children with symptoms of certain personality disorders may be diagnosed with other developmental psychiatric illnesses like conduct disorder (CD). 

The essential components of "borderline personality disorder" include a pattern of impulsivity and instability of behaviors, interpersonal relationships, and self-image. This personality disorder typically begins in early adulthood (ages 18-25), but has temperamental underpinnings in childhood and adolescence. 

"Post-traumatic stress" is an anxiety disorder characterized by intense periods of anxiety after intense trauma. Examples of such trauma include warfare, car accidents, assault, etc. They are known to continue for long periods of time. As John has returned from warfare and his anxiety seems to be continuing, it is likely that he is experiencing post-traumatic stress. 

Personality disorders are set apart from other disorders due to their inflexible nature over time. The theory is that the dysfunction/distress stems from deviations in personality that are much more difficult to change compared to the causes of other kinds of mental disorders. 

Many people afflicted with schizophrenia report having hallucinations (hearing voices in one's head) and/or delusions (erroneous beliefs about being persecuted) while having a schizophrenic episode. Hallucinations and delusions are significantly less common in depressed, ADHD, CD, and selective mutism patients. 

Men tend to develop schizophrenia earlier than women, in that the average age of onset of schizophrenia for men is 18 and the average age of onset for women is 25. Many other psychological disorders come to fruition during the "young adult" period, including antisocial personality disorder and various mood disorders.

A negative symptom is one that dispells attention from a subject. Alternatively, positive symptoms attract attention to a subject. While a lack of emotion is a negative symptom, hallucinations, delusions, and disorganized speech are all positive symptoms.

The main tenet of the neurodevelopmental hypothesis is that schizophrenia is the result of early brain insult during either pre- or perinatal development, which is later expressed in the mature brain. Many have suspected that this insult could be due to environmental factors that mothers endure or are exposed to, as evidenced by the many schizophrenic children born from starving mothers during World War II, or from mothers exposed to toxins. The insult could also be due to genetic inheritance.

Mania (a period of especially high activity and euphoria) is not directly associated with schizophrenia; it is commonly associated with bipolar disorder. The other answer choices are four of the most common symptoms of schizophrenia.