Schizophrenia can profoundly affect the way a person thinks, feels, perceives the world, and manages everyday life. Some symptoms are immediately noticeable, while others develop quietly and may be mistakenly attributed to laziness, indifference, or a lack of willpower.

In American psychiatry, these experiences are commonly described as positive symptoms and negative symptoms. The words “positive” and “negative” do not mean good and bad. Instead, they describe whether something has been added to a person’s usual experience or whether an important ability has been reduced.

Positive Symptoms: When New Experiences Appear

Positive symptoms are experiences or behaviors that were not present before the illness. They may include:

• Hallucinations, especially hearing voices
• Delusions, or firmly held beliefs that are not supported by reality
• Disorganized thinking and speech
• Severely disorganized or unusual behavior
• The belief that thoughts, emotions, or actions are being controlled by an outside force

During psychosis, these experiences can feel completely real. A person may believe they are being watched, threatened, influenced, or sent hidden messages. Fear and anxiety may become overwhelming because the person is responding to a reality that others do not share.

Catatonia may involve very limited movement and speech or, in some cases, intense motor activity. However, it is relatively uncommon and can occur with conditions other than schizophrenia.

Negative Symptoms: When Abilities Begin to Fade

Negative symptoms are often less dramatic, but they can have a profound effect on independence and quality of life. They may include:

• Avolition: difficulty beginning or continuing purposeful activities
• Anhedonia: reduced ability to experience or anticipate pleasure
• Alogia: decreased speech or limited verbal expression
• Asociality: reduced interest in social contact
• Diminished emotional expression: limited facial expressions, gestures, or changes in voice

A person who once studied, worked, exercised, and maintained a daily routine may gradually lose the motivation to continue these activities. Even basic tasks—showering, brushing teeth, preparing food, answering messages, or leaving home—may begin to feel almost impossible.

These changes are not character flaws. They are genuine symptoms that can significantly interfere with education, employment, relationships, and self-care. Clinicians must also determine whether apparent negative symptoms are related to depression, medication side effects, ongoing psychosis, substance use, or social isolation.

The Dopamine Explanation Is Not So Simple

Schizophrenia is sometimes described as a disorder caused by “too much dopamine,” but that explanation is fundamentally incomplete.

Research suggests that increased dopamine activity in parts of the striatum is associated with psychotic symptoms such as hallucinations and delusions. However, negative and cognitive symptoms may involve entirely different brain circuits and several neurotransmitter systems, including both dopamine and glutamate.

This means schizophrenia cannot be explained by one chemical being simply too high or too low throughout the brain. It is a complex disorder involving communication between multiple brain regions, along with genetic, developmental, and environmental factors.

Why Treatment Can Be Challenging

During an acute psychotic episode, the first priorities are reducing severe distress, treating hallucinations and delusions, managing agitation, and protecting the person when an immediate safety risk exists. Schizophrenia itself, however, should not automatically be associated with aggression or violence.

Antipsychotic medications are generally more effective at reducing positive symptoms than persistent negative symptoms. First-generation and second-generation antipsychotics work in different ways and have different side-effect profiles, but the second-generation group is not uniformly superior in every area. Medication must therefore be carefully selected according to the individual’s symptoms, previous response, physical health, and tolerance of side effects.

Treatment should not end when hallucinations or delusions become less intense. Negative symptoms may require medication review, psychosocial treatment, cognitive and behavioral support, family education, supported employment or education, and help rebuilding daily routines.

The quiet symptoms deserve as much attention as the visible ones. With early, consistent, and person-centered care, many people with schizophrenia can continue their education, work, maintain relationships, and live with greater independence.

References

• National Institute of Mental Health. Schizophrenia. NIH Publication No. 24-MH-8082. Revised 2024. No page numbers are provided in the online publication.
  Explains psychotic, negative, and cognitive symptoms and describes medication, psychosocial treatment, family support, and coordinated specialty care in the United States.
• Correll CU, Schooler NR. Negative Symptoms in Schizophrenia: A Review and Clinical Guide for Recognition, Assessment, and Treatment. Neuropsychiatric Disease and Treatment. 2020;16:519–534. doi:10.2147/NDT.S225643.
  Describes the main negative symptom domains, their impact on functioning, and the distinction between primary symptoms and symptoms caused by depression, medication effects, psychosis, or environmental factors.
• McCutcheon RA, Krystal JH, Howes OD. Dopamine and Glutamate in Schizophrenia: Biology, Symptoms and Treatment. World Psychiatry. 2020;19(1):15–33. doi:10.1002/wps.20693.
  Reviews modern evidence on dopamine and glutamate and explains why schizophrenia cannot be reduced to a simple theory of excessive dopamine throughout the brain.