Use of Animals in Use of Animals in Research into Research into SchizophreniaSchizophrenia

Why use animals?

• Basically, in order to do research you wouldn’t be able to do with humans for ethical reasons.

• Schizophrenia may be unique only to humans• However, our hormonal system, nervous

system, brain structure is similar to animals– E.g., Rats and humans have the same hind-, mid-

and fore-brain

• How do researchers ‘give’ animals schizophrenia?• Hyperactivity in rats is often induced by drugs (eg.

amphetamine) which are similar to the positive symptoms of schizophrenia.

• Then, the rat might be given a medication (like Haldol) which reduces symptoms by blocking dopamine receptors in the brain.

• This then helps understand how certain anti psychotic medications work and how new medications can be developed.

• In fact, studies in rats showed researchers that psychosis in humans is partly due to too much dopamine in the brain – which then allowed medications to be developed to treat this chemical imbalance.

Animals and Schizophrenia

Recap Genetic Explanation for Schizophrenia

Recap Gottesman and Sheilds (1991)

• A• P

• R• C

Evaluate the Genetic Explanation for Schizophrenia

• Aim: to look at how genes affect schizophrenia in rats

• Method: Bred rats with a genetic variation believed to be associated with schizophrenia in humans.

• Results: Genetically modified rats were apathetic and socially withdrawn (negative symptoms of schizophrenia)

• Conclusion: Study supports the role of genes in schizophrenia.

Wood et al., (1998)

Recap Dopamine Hypothesis for schizophrenia

Evaluate theDopamine Hypothesis for schizophrenia

• Aim: to see whether schizophrenia-like symptoms could be induce in non-human animals by giving them amphetamines.

• Method: Injecting rats with doses of 1-20 mg/kg of amphetamines. They then went on to test chickens, pigeons, cats, dogs and squirrels.

• Results: All known symptoms of schizophrenia were recorded including stereotypical activity.

• Conclusion: Study supports the Dopamine Hypothesis of schizophrenia.

Randrup and munkvad, (1966)

Evaluation

• Important in developing new drugs that can be used to treat symptoms of schizophrenia in humans.

• Easy way to do experiments in order to understand the role of genetics in schizophrenia

• Can do research that would be ethically wrong to do on humans

Evaluation of animal studies: Strengths

• The nervous system between rats and humans is not the same, and different parts of the brain are different sizes (e.g., the fore-brain in humans is huge and the cortex is larger)

• Cannot replicate schizophrenia in mice, only approximate symptoms of schizophrenia

• Is it ethically okay to use animals for psychological research?

Evaluation of animal studies: Weaknesses

Questions

• Why do researchers use animals to study schizophrenia?

• What did Wood et al. (1998) find in their study of rats and humans?

• What is one strength of using animals to study schizophrenia?

• What is one weakness of using animals to study schizophrenia?

Exam QuestionsJune 2010

a) Describe the symptoms of schizophrenia.(4 marks).

(b) (i) Describe one explanation for schizophrenia.(4 marks)

(ii) Evaluate the explanation for schizophrenia you have given in (b)(i). (5 Marks)

(c) Describe one research method used to study schizophrenia. (4 Marks)