15.8 Schizophrenia — Genetics, Brain Chemistry, and the Reality Break | Psychology 2e

• Understand the prevalence, typical onset, and profound life-altering impact of schizophrenia.
• Differentiate schizophrenia from dissociative identity disorder and understand the origin of the 'split mind' term.
• Identify and describe the 'additions' to normal experience, such as hallucinations, delusions, and disorganized thinking.
• Identify and describe the 'subtractions' from normal experience, such as avolition, alogia, and anhedonia.
• Understand how adoption studies demonstrate the genetic component of schizophrenia.
• Explain how genetic predisposition interacts with environmental stress to trigger schizophrenia.
• Understand the role of dopamine, serotonin, and structural brain abnormalities in schizophrenia.
• Identify prenatal environmental factors and the role of marijuana use as triggers for schizophrenia.
• Understand how the justice system handles severe psychosis and clarify public misconceptions about insanity pleas.
• Learn about prodromal symptoms and the importance of early intervention in preventing full psychotic breaks.
• Up next in “Psychology 2e — Full Course (OpenStax) | Intro Psychology Lectures”15.9 Dissociative Disorders — When the Mind Builds Its Own Firewalls | Psychology 2e

This lesson dives deep into schizophrenia — one of the most complex and widely misunderstood psychological disorders — drawing directly from Section 15.8 of OpenStax Psychology 2e. From clearing up the persistent split-personality myth to unpacking the biological and environmental forces that shape the disorder, the video walks through symptoms, causes, and the science of early intervention. Whether you're studying for an exam or simply want to understand what's really happening inside the brain, this discussion offers a clear, grounded look at the research. In this video: • Positive vs. negative symptoms explained: hallucinations, delusions, disorganized thinking, catatonia, avolition, alogia, anhedonia, and more • Why schizophrenia is NOT the same as dissociative identity disorder, and what Eugen Bleuler's 1911 Greek etymology actually meant • The diathesis-stress model illustrated by Tianari et al.'s adoption study: 36.8% risk in disturbed environments vs. 5.8% in healthy ones with the same genetic vulnerability • The dopamine hypothesis: overabundance in the limbic system linked to positive symptoms; low levels in the prefrontal cortex linked to negative symptoms • Structural brain differences — enlarged ventricles and frontal lobe gray matter loss — and what they mean for thinking and behavior • Prenatal risk factors (influenza exposure, obstetric complications, maternal stress) and early marijuana use as an environmental trigger for those with genetic vulnerability • Prodromal symptoms and why early identification — unusual thoughts, creeping paranoia, odd communication — offers the best hope for intervention before full psychosis #OpenStax #Psychology #Schizophrenia #AbnormalPsychology #MentalHealth OpenStax Content adapted from "OpenStax Psychology 2e", by OpenStax licensed under CC BY 4.0. Content based on Web Version: Apr 23, 2026. Read the textbook online https://openstax.org/details/books/psychology-2e Music first girl talking to me. by ikkun (ex. Barradeen) | https://soundcloud.com/ikkunwastaken Royalty Free Music by https://www.free-stock-music.com Creative Commons / Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0) https://creativecommons.org/licenses/by-sa/3.0/deed.en_US