As a time of major brain development, adolescence is a vulnerable period for early life stress. To better determine the nature of chronic stress and its relationship to schizophrenia, Anya Savransky, from the Maryland Psychiatric Research Center, University of Maryland School of Medicine in Baltimore, and colleagues compared data from 58 patients with SSD with that from 34 age- and sex-matched controls.
The sooner clinicians diagnose and treat schizophrenia, the better the prognosis. Before full-blown psychotic symptoms appear, individuals may experience changes in cognition, behavior, and function. Therefore, it is crucial to identify populations at high risk for schizophrenia.
Early life stressors, including those in utero, can trigger the processes that lead to schizophrenia and affective disorders in adulthood. Nascent evidence points to susceptibility during brain development that contributes to the early-stage schizophrenia phenotype. Stress during critical periods of development and risk for schizophrenia [published online January 30, ].
Schizophr Res. Maternal stress, prenatal medical illnesses and obstetric complications: risk factors for schizophrenia spectrum disorder, bipolar disorder and major depressive disorder.
Psychiatry Res. Early life experiences and social cognition in major psychiatric disorders: a systematic review. Eur Psychiatry. The main psychological triggers of schizophrenia are stressful life events, such as:. These kinds of experiences, although stressful, do not cause schizophrenia. However, they can trigger its development in someone already vulnerable to it. Drugs do not directly cause schizophrenia, but studies have shown drug misuse increases the risk of developing schizophrenia or a similar illness.
Certain drugs, particularly cannabis , cocaine, LSD or amphetamines, may trigger symptoms of schizophrenia in people who are susceptible. Using amphetamines or cocaine can lead to psychosis, and can cause a relapse in people recovering from an earlier episode. Research has shown that teenagers and young adults who use cannabis regularly are more likely to develop schizophrenia in later adulthood.
Page last reviewed: 11 November Next review due: 11 November Causes - Schizophrenia. Increased risk Genetics Schizophrenia tends to run in families, but no single gene is thought to be responsible.
Brain development Studies of people with schizophrenia have shown there are subtle differences in the structure of their brains.
Neurotransmitters Neurotransmitters are chemicals that carry messages between brain cells. Pregnancy and birth complications Research has shown people who develop schizophrenia are more likely to have experienced complications before and during their birth, such as: a low birthweight premature labour a lack of oxygen asphyxia during birth It may be that these things have a subtle effect on brain development.
Triggers Triggers are things that can cause schizophrenia to develop in people who are at risk. In the current study, these new insights come from examining two important chemical messengers -- dopamine and cortisol -- in people under stress.
Dopamine is a neurotransmitter, a chemical that carries signals from one brain cell, or neuron, to another. In this study, the researchers focused on dopamine released in the prefrontal cortex, the region at the front of the brain involved in complex functions, including regulating emotions.
Cortisol is a hormone, released from the adrenal glands to help the body handle stressful situations. In healthy individuals, both dopamine and cortisol levels typically increase when people experience stress.
This link between dopamine release and cortisol release did not appear in people with schizophrenia. To investigate responses to stress, the researchers used a math test. In the first stage of the study, participants answered math questions on a computer screen without any time limit while a positron emission tomography PET scanner produced an image of dopamine in their brain as they completed the task.
In the second stage -- the stress test -- participants answered math questions under time constraints and while receiving negative verbal feedback, also in the PET scanner. Saliva samples were collected during both stages to measure cortisol levels. The study included 14 people with schizophrenia, 14 people at clinical high risk for psychosis and 12 people without mental illness. The findings build on Dr. Mizrahi's earlier research in another region of the brain, the striatum.
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