Schizophrenia

3% of the population suffer from schizophrenia The word schizophrenia means ‘split mind’ The DVM is used to diagnose schizophrenia A delusion is a positive symptom The symptoms must persist for one year in order to be diagnosed as schizophrenic The flattening of emotion is a positive symptom True/False

Learning Objectives  describe the role of genetics in schizophrenia  describe family, twin and adoption studies which study the role of genetics in schizophrenia  explain how family, twin and adoption studies support the genetic explanation of schizophrenia LEARNING OBJECTIVES

Biological V Psychological Nature V Nurture

Biological Explanations  Genetics  Biochemistry  Brain Structure

Graph Activity

Research Studies What is the logic behind conducting twin studies? What is the logic behind conducting adoption studies? TASK  Complete twin and adoption recap task RESEARCH STUDIES

Overview Genetic explanation state that the genes for schizophrenia are inherited which could be the reason for some symptoms It is thought that the presence of certain types of genetic mutations may be necessary for the disorder to be triggered – i.e. predisposed to the disorder These genes can cause critical neural pathways in the brain to be disrupted or damaged Therefore behaviour that is controlled by these pathways will not occur or even develop properly It is also possible that it is genetics that cause excess production of/sensitivity to dopamine… this leads us to the Dopamine Hypothesis …. Overview

AO2 What should concordance be for MZ twins if genetics was the only explanation? Is there another explanation for high concordance amongst family members, particularly identical twins? Why is concordance for MZ twins always higher than that for DZ twins? What is the problem with retrospective data? If diagnostic criteria has changed over time how will it affect the research findings? Read over Gottesman & Shields (1966) and complete pgs in your packs AO2/AO3 questions