Substantial evidence indicates a genetic foundation for schizophrenia. For instance, an individual's risk of developing the disorder is approximately six times higher if they have a parent with schizophrenia compared to someone who does not. Furthermore, the likelihood of developing schizophrenia is directly correlated with the degree of genetic similarity to family members who have been diagnosed with the condition.

Hereditary Component of Schizophrenia

Schizophrenia is often associated with abnormalities in neurotransmitters. Huge amount of dopamine in the limbic system may be responsible for symptoms such as hallucination, while a low amount in the prefrontal cortex is associated with negative schizophrenic symptoms. Theories such as the Dopamine Hypothesis has also been proposed regarding schizophrenia and dopamine. The relationship between dopamine and serotonin is also being studied and explored. 

Biological Causes of Schizophrenia: Neurotransmitters

People with schizophrenia often have larger ventricles. In their frontal lobe, they may also have less grey matter, which can impact their ability to execute behavior, talk, and focus.

Brain Anatomy and Schizophrenia

An individual may suffer from schizophrenia later in their life if they experience problems in their brain development. Children with obstetric birth complications show a higher risk for schizophrenia. Events that happen to the mother during pregnancy (Influenza, death of a relative) can also increase the child's risk.

Pregnancy and Schizophrenia: The Child

Longitudinal studies suggest that marijuana use is a significant risk factor in the development of schizophrenia. While individuals with schizophrenia are more likely to use marijuana, research indicates a potential causal relationship rather than just a correlation. The risk increases substantially with more frequent use. However, marijuana use is not considered an essential or sufficient cause, as not all individuals with schizophrenia have used it, and most users do not develop the disorder. The evidence suggests that marijuana use may play a role in triggering the illness, particularly in individuals who already have an underlying vulnerability.

Marijuana Use as a Risk Factor for Schizophrenia

- Genetic causes
- Biological causes
- Brain anatomy
- Pregnancy
- Marijuana

New York University

New Mexico Highlands University

The primary symptoms of schizophrenia are categorized into five main types: hallucinations, delusions, disorganized thinking, disorganized or abnormal motor behavior, and negative symptoms. When the disorder is active, individuals may struggle to differentiate between real and unreal experiences. The severity, duration, and frequency of these symptoms can vary, and severe psychotic symptoms often decrease with age.

Schizophrenia Symptoms

Spielman, R. M., Jenkins, W. J., & Lovett, M. D. (2020, April 22). Psychology (2nd ed.). OpenStax. https://openstax.org/books/psychology-2e/pages/1-introduction

OpenStax Psychology (2nd ed.) Textbook

(those abnormally present) Hallucinations, such as hearing voices or seeing things that do not exist, paranoia and exaggerated or distorted perceptions, beliefs and behaviors.

Positive Symptoms of Schizophrenia 

Confused and disordered thinking and speech, trouble with logical thinking and sometimes bizarre behavior or abnormal movements.

Disorganized Symptoms of Schizophrenia 

Cognition is another area of functioning that is affected in schizophrenia leading to problems with attention, concentration and memory, and to declining educational performance.

Cognitive Symptoms of Schizophrenia 

Negative symptoms involve significant reductions and absences of typical behaviors, emotions, or motivations (Green, 2001). These symptoms signify a loss of normal functions and include diminished emotional expression, avolition, alogia, asociality, and anhedonia.

Negative Symptoms of Schizophrenia

Prodromal symptoms in schizophrenia refer to the slight, early symptoms of psychosis. This could mean that the individual is going through odd communications, paranoia, and delusions. 

Prodromal Symptoms of Schizophrenia

Possible Causes of Schrizophrenia

Read the following clinical description. Identify one example for each of the following three symptom categories: a delusion, disorganized thinking, and a negative symptom. For each example, briefly explain your reasoning.

Learn Before

Related

Learn After