WEEK 5: 14.02.07
CHAPTER 13: PSYCHOLOGICAL DISORDERS
Module 13.4 Schizophrenia
Approximately 7.6 out of 1,000 adults will experience schizophrenia at some
point in their lives
SYMPTOMS AND TYPES OF SCHIZOPHRENIA
Schizophrenia refers to a collection of disorders characterized by chronic and significant
breaks from reality, a lack of integration of thoughts and emotions, and serious problems
with attention and memory.
Hallucinations are false perceptions of reality such as hearing internal voices.
Delusions are false beliefs about reality.
o I.e. schizophrenics may have delusion of grandeur, believing that they’re
the Pope or Jesus
Men are more likely to have schizophrenia (7:5 ratio) and tend to develop it
earlier in life than women
Many different types of schizophrenia such as the following:
1. Paranoid schizophrenia: symptoms include delusional beliefs that one is
being followed, watched, or persecuted, and may also include delusions of
2. Disorganized schizophrenia: symptoms include thoughts, speech,
behavior, and emotion that are poorly integrated and incoherent. May also
show inappropriate, unpredictable mannerisms.
3. Catatonic schizophrenia: symptoms include episodes in which a person
remains mute and immobile – sometimes in bizarre positions – for
extended periods. Individuals may also exhibit repetitive, purposeless
4. Undifferentiated schizophrenia: this category includes individuals who
show a combination of symptoms from more than one type of
5. Residual schizophrenia: this category reflects individuals who show
some symptoms of schizophrenia but are either in transition to a full
blown episode or in remission.
Some mental health professionals prefer classifying symptoms based on positive
and negative categories rather than using subtypes
Positive symptoms refer to behaviors that should not occur, such as confused and
paranoid thinking, and inappropriate emotional reactions.
Involves the presence of maladaptive behavior
Negative symptoms involve the absence of adaptive behavior.
o I.e. absent or flat emotional reactions and lack of speech and motivation
Individuals with schizophrenia experience several problems with cognitive
1 o Ranging from basic startle responses – such as eye blinking – to skills
involved in standardized achievement tests
o Complex cognitive abilities involve prefrontal cortex, which displays
significant neurological decline
Studies using twins, adoptions, and family history methods indicate as genetic
relatedness increase so does chance that a relative of a person with schizophrenia
will also develop the disease increases
I.e. identical twin with schizophrenia, other twin has 2550% chance of
Scientists discovered distinct pattern of genetic irregularities found in 15% of
Schizophrenia and the Nervous System
People with schizophrenia have very noticeable increase in size of the brain
ventricles, which are fluidfilled spaces occurring within the core of the brain
Their ventricles are 2030% larger than people without schizophrenia
Larger ventricular spaces corresponds to loss of brain matter; the volume of the
entire brain is reduced ~2%
Reduced volume can be found in structures like the amygdala and hippocampus
Anatomical changes associated with schizophrenia mayn’t cause the disorder but
might tend to occur in people who’ve it