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Schizophrenia was first identified [br]more than a century ago,

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but we still don’t know its exact causes.

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It remains one of the most misunderstood [br]and stigmatized illnesses today.

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So, let’s walk through what we do know— [br]from symptoms to causes and treatments.

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Schizophrenia is considered a syndrome,

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which means it may encompass [br]a number of related disorders

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that have similar symptoms [br]but varying causes.

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Every person with schizophrenia [br]has slightly different symptoms,

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and the first signs can be easy to miss— [br]subtle personality changes, irritability,

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or a gradual encroachment [br]of unusual thoughts.

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Patients are usually diagnosed [br]after the onset of psychosis,

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which typically occurs in the late teens [br]or early twenties for men

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and the late twenties [br]or early thirties for women.

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A first psychotic episode can feature [br]delusions, hallucinations,

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and disordered speech and behavior.

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These are called positive symptoms,

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meaning they occur [br]in people with schizophrenia

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but not in the general population.

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It’s a common misperception [br]that people with schizophrenia

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have multiple personalities,

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but these symptoms indicate a disruption [br]of thought processes,

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rather than the manifestation [br]of another personality.

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Schizophrenia also has negative symptoms,

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these are qualities that are reduced [br]in people with schizophrenia,

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such as motivation, [br]expression of emotion, or speech.

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There are cognitive symptoms as well, [br]like difficulty concentrating,

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remembering information, [br]and making decisions.

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So what causes the onset of psychosis?

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There likely isn’t one single cause,[br]but a combination

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of genetic and environmental [br]risk factors that contribute.

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Schizophrenia has some of the strongest [br]genetic links of any psychiatric illness.

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Though about 1% of people [br]have schizophrenia,

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children or siblings of people [br]with schizophrenia are ten times likelier

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to develop the disease,

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and an identical twin [br]of someone with schizophrenia

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has a 40% chance of being affected.

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Often, immediate relatives [br]of people with schizophrenia

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exhibit milder versions of traits [br]associated with the disorder—

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but not to an extent [br]that requires treatment.

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Multiple genes almost certainly [br]play a role,

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but we don’t know how many, or which ones.

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Environmental factors like exposure [br]to certain viruses in early infancy

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might increase the chance [br]that someone will develop schizophrenia,

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and use of some drugs, [br]including marijuana,

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may trigger the onset of psychosis

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in highly susceptible individuals.

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These factors don’t affect [br]everyone the same way.

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For those with very low genetic risk,

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no amount of exposure [br]to environmental risk factors

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will lead them to develop schizophrenia;

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for those with very high risk, moderate [br]additional risk might tip the balance.

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The antipsychotic drugs used to treat [br]schizophrenia have helped researchers

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work backwards to trace signatures [br]of the disorder in the brain.

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Traditional antipsychotics [br]block dopamine receptors.

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They can be very effective [br]in reducing positive symptoms,

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which are linked to an excess of dopamine [br]in particular brain pathways.

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But the same drugs [br]can make negative symptoms worse,

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and we’ve found that negative symptoms [br]of schizophrenia may be tied

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to too little dopamine [br]in other brain areas.

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Some people with schizophrenia [br]show a loss of neural tissue,

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and it’s unclear whether this atrophy [br]is a result of the disease itself

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or drug-induced suppression of signaling.

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Fortunately, newer generations [br]of antipsychotics aim to address

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some of these issues by targeting [br]multiple neurotransmitters,

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like serotonin in addition to dopamine.

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It’s clear that no one transmitter system [br]is responsible for all symptoms,

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and because these drugs affect signaling [br]throughout the brain and body,

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they can have other [br]side effects like weight gain.

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In spite of these complications, [br]antipsychotics can be very effective,

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especially when combined [br]with other interventions

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like cognitive-behavioral therapy.

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Electroconvulsive therapy, though [br]it provides relatively short-lived relief,

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is also re-emerging [br]as an effective treatment,

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especially when other options [br]have failed.

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Early intervention [br]is also extremely important.

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After months or years [br]of untreated psychosis,

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certain psychoses can become embedded [br]in someone’s personality.

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And yet, the dehumanizing stigma [br]attached to this diagnosis

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can prevent people from seeking help.

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People with schizophrenia [br]are often perceived as dangerous,

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but are actually much more likely [br]to be the victims of violence

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than the perpetrators.

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And proper treatment may help reduce [br]the likelihood of violence

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associated with schizophrenia.

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That’s why education— for patients, [br]their families, and their communities—

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helps erode the stigma [br]and improves access to treatment.