1. ETIOLOGY OF
SCHIZOPHRENIA
PRESENTATION BY GROUP 2

2. GROUP MEMBERS
 DENNIS NJERESA
 FALES KAONGA
 PRISCA MAJONI
 LOYCE THOMO
 DICKSON AARON
 CYNTHIA MKWENDE
 BRENDA DZIMBIRI
 CHARLES NKHWAZI

3. BIOCHEMICAL INFLUENCES
Biological influences:
Genetic/heredity
Neurotransmitters
Neuroanatomical

4. 1. GENETIC/HEREDITY
 A person may be at an increased risk of developing schizoaffective
 disorder if a first-degree relative such as parent, siblings or child has it
 It has been observed that schizophrenia and schizophrenic like symptoms
occur at an increased rate in relatives with schizophrenia
 If one parent has schizophrenia, about 12% of his or her children develop
the disease
 If both parents have schizophrenia up to 46% of their children will get the
disease
 Among identical twins 40% to 50% will both develop schizophrenia
 Fraternal twins, 15% will develop

5. GENETIC/HEREDITY CONT…
 It may also occur due to interaction with environment which
lead to mutation of genes which predispose someone to
develop schizophrenia

6. 2.NEUROTRANSMITTERS
 Neurons have a role of conducting the transmission of nerve
impulse. Increase in the transmitters due to decrease in the
metabolism of dopamine leads to psychotic disorders
 For instance, excess dopamine leads to schizophrenia
 Some drugs like levodopa induce the release of dopamine
thereby making the neurotransmitters to be in excess hence
can exacerbate the symptoms of schizophrenia in psychotic
diets

7. 3.NEUROANATOMICAL
 Disruptions in the connecting and communication within neural circuitry
(communication pathway) are thought to be severe in schizophrenia
 Structural cerebral abnormalities could cause disruptions to the entire
circuit in the brain
 Finding:
 Enlargement of the lateral cerebral ventricles
 Cortical atrophy
 Third ventricular dilation
 Ventricular asymmetry
 Cerebellar atrophy

8. DIAGNOSTIC FEATURES OF
SCHIZOPHRENIA
 Signs and symptoms of schizophrenia are the cardinal features of clinical
manifestation to come up with the diagnosis
 These signs and symptoms of schizophrenia are categorised into two
categories namely positive and negative

9. Signs and symptoms
positive signs and symptoms
This category comprises of symptoms which are usually characterised as pathological
excess. This is because the symptoms in this group add to the person`s behaviour
rather than subtract from the person`s behaviour.
Positive symptoms are highly exaggerated ideas, perception or actions
examples
1. Hallucination
This is when the client has a false sensory perception( external stimulus)
Person might hear, see, smell, feel or taste things that are not there. Therefore is
abnormal responses to the eternal stimulus.

10. cont
 Types of hallucination
1. Auditory
It is a false auditory perception. Client hears the voices that are not present.
2 . Visual hallucination
Client sees things that are not there e.g. lights, objects, people or patterns.
3 . Olfactory
False perception of smell which can either good or bad
4 . Gustatory
False perception of taste.
5 . Tactile
This creates feelings of things moving on your body.

11.  DELUSION
False fixed beliefs which is not consistent with intelligence and cultural background.
False beliefs that are firmly and consistently held despite disconfirming evidence or
logic.
This believes do not change even if the person is presented with new ideas or facts

12.  Disorganized Speech /Thought Disturbances
Problems in organizing ideas and speaking so that a listener can understand.
They are unable to follow the conversation when they are talking, their words can
come out jumbled and not make sense
e.g. neologisms-new, seemingly meaningless words that are formed by combining
words(invention)

13.  Grossly disorganised/disorganised motor disturbances
Also known as catatonic behaviour
This is characterised by disruption in movement for example repeated movement that
serve no purpose (mannerism).
Strange gestures and grimaces.
Trouble concentrating

14. Negative symptoms
 This is the behaviour deficits that endure beyond an acute episode of
schizophrenia . More negative symptoms are associated with poorer prognosis.
These symptoms might be secondary to medications and/ or institutionalisation.
Types of negative symptoms
1 . Lack of pleasure (anhedonia)
The person may not seen to enjoy anything anymore
Inability to feel pleasure/ lack of interest or enjoyment in activities or relationship.

15. cont
2 . A volition
This is when a person struggles with the basic activities of daily life.
Person lack energy to engage in routine activities e.g. personal hygiene and/ or goal
directed activities e.g. work, school
3 . A logia
also known as poverty of speech
They might not talk much or poverty of content of speech ( little information is
conveyed)
4 . A sociality/ withdrawal
Impairment in social relationship, few friends, poor social skills, little interest in being
with people.

16. cont
 5 . Flat affect
No stimulus can elicit an emotional response
Patient may stare vacantly with lifeless eyes and expressionless face
Voice may be toneless

17. Thank you

18. references
Boyd, M. A. (2012). Psychiatric Nursing Contemporary Practice. Philadelphia: Lippincott
Williams & Wilkins.
Townsend, M. C. (2011). Essentials of Psychiatric Mental Health Nursing. Philadelphia: F.A.
Davis Company.
Uys, L., & Middleton, L. (2004). mental health nursing a south African perspective. Cape
Town.
Womble, D. M. (2004). Introductory Mental Health Nursing. Philadelphia: Lippincott
Williams & Wilkins.