Psychosis (Week 10 / Chapter 14) Flashcards
Early Figures in Diagnosing Schizophrenia
Emil Kraepelin (1899)
Eugen Bleuler (1908)
Earliest categorization of schizophrenia
▪ He combined previously distinct disorders of insanity:
– Catatonia
– Hebephrenia
– Paranoia
- Into Dementia praecox: used to capture this cluster of symptoms;
thought that had the same underlying cause; later added
hallucinations, delusions, negativism, and stereotyped behavior - Manic Depressive Illness
Emil Kraepelin (1899)
Swiss psychiatrist, introduces the term
Schizophrenia form “split (skhizen) mind (phren)”
– They can’t connect one idea/experience/perception to the next
– “Associative splitting” of personality functions – there is a
disconnection/ a “breaking of associative threads”
– Associations allow us to think and function efficiently, if there is a
breakdown, there is a breakdown of thought and other processes
Eugen Bleuler (1908)
Bleuler agrees Schizophrenia is heterogenous
but…
Remember Kraeplin was someone who focused on early adverse
experiences
▪ Bleuler: this is a thought disorder that connects all the symptoms into a
heterogeneous presentation
▪ Several behaviours or symptoms not shared by all people given
diagnosis of schizophrenia
▪ Clusters of symptoms identified: Positive symptoms (include
delusions and hallucinations); negative symptoms (deficits e.g.,
diminished emotional expression), disorganized symptoms or
catatonia (rambling speech, erratic behavior).
– So much variability in presentation
▪ Is schizophrenia really a thing? Construct validity?
▪ Is it best used an umbrella term, e.g., schizophrenia spectrum
disorder?
Polythetic disorder
▪ Group of diagnoses related to schizophrenia
▪ DSM‐5 includes a dimensional assessment of symptoms on a 0–4 scale
– 0 indicated no symptoms
▪ The symptoms of schizophrenia can be divided into “positive,”
“negative,” and “disorganized.”
▪ Positive symptoms: are active manifestations of abnormal behaviour, or
an excess or distortion of normal behaviour, and include delusions and
hallucinations.
▪ Negative symptoms: involve deficits in normal behaviour, in such areas as
speech, affect, and motivation.
▪ Disorganized symptoms: include rambling speech, erratic behaviour, and
inappropriate affect.
Schizophrenia spectrum disorder
50%–70% people with schizophrenia experience ________
symptoms: hallucinations, delusions, or both
Positive Symptoms
Delusions
▪ A disorder of thought content
– Delusion of grandeur
– Delusions of persecution
– Cotard’s syndrome
– Capgras syndrome
Hallucinations
▪ Experience of sensory events
without input from
surrounding environment
▪ Auditory hallucinations:
hearing things that aren’t
there
– Associated with listening to
own thoughts
– Abnormal activation of primary
cortex
– Increased metabolic activity in
left auditory cortex (C
Negative Symptoms of Schizophrenia
▪ Absence or insufficiency of normal behaviour
▪ Seen in approximately 25% with schizophrenia
▪ Avolition
▪ Alogia
▪ Anhedonia
▪ Asociality
▪ Affective flattening
inability to initiate/persist in activities
Avolition
absence of speech; brief replies
Alogia
lack of pleasure experienced
Anhedonia
lack of interest in social interactions
Asociality
no open reaction to emotional
situations
Affective flattening
Disorganized Symptoms
– Disorganized speech
– Inappropriate affect and Disorganized behaviour (ie; laughing or crying at inappropriate times)
- Catatonic immobility
keeping body and limbs in
the position they are put in by someone else
Catatonic immobility
communication problems in schizophrenia
Disorganized speech
DSM5TR Schizophrenia
Text / Slide
STUDY SCHIZOPHRENIFORM/SHIZOAFFECTIVE/DELUSIONAL DISORDER DSM-5
TEXT / SLIDE!
Prevalence and Causes of Schizophrenia
Statistics
– 0.2% to 1.5% in general population
– less than average life expectancy
– Men and women affected at same rate
Development
– Age of onset: Onset of schizophrenia is greatest in early
adulthood and declines with age for males, whereas the
reverse is true for females.
– Early brain damage cause?
Natural History of Schizophrenia
SEE SLIDE / TEXTBOOK
Prevalence and Causes of Schizophrenia: Cultural Factors
– Cultural norms
– Cultural variations
– Stereotypes and bias: misdiagnoses
– Treatment outcomes are better in poorer countries
Prevalence and Causes of Schizophrenia: Genetic Factors
Genetic Influences
▪ Multiple gene variances combine to produce vulnerability
Family Studies
▪ Children of schizophrenic parents likely to have it too
▪ Seen within families
▪ Predisposition may be inherited
Twin Studies
– Genain quadruplets
– All four of the identical quadruplets developed
schizophrenia (same genes, same environment)
– Time of schizophrenia onset, symptoms, diagnoses,
course, outcomes differed from sister to sister
Adoption Studies
▪ Gene‐environment interaction observed
Offspring of Twins
▪ 1.7% of children with nonschizophrenic parents develop
schizophrenia
Gene‐Environment Interaction
▪ Genes may act as vulnerability factors
▪ Interact with specific environmental pathogens at crucial
developmental stages
▪ Leading to development of schizophrenia
Linkage and Association Studies
▪ Genetic risk may arise from a large number of
common genes
▪ Each has a small effect that might be detected by
genome‐wide association studies
The Search for Markers
▪ Eye‐tracking deficit may be a marker for
schizophrenia
Evidence for Multiple Genes
▪ Schizophrenia involves more than one gene; located
at different sites throughout chromosomes
▪ This is referred to as quantitative trait loci
