8 birds rodents 5 neurotransmitters

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Learning Objectives You will be able to describe and evaluate why animals are used in lab studies when researching into drugs. You will be able to describe and evaluate how animals are used to research drugs. You will evaluate animal research in terms of both practical and ethical issues.

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Learning ObjectivesYou will be able to describe and evaluate why animals are used in lab studies when researching into drugs.

You will be able to describe and evaluate how animals are used to research drugs.

You will evaluate animal research in terms of both practical and ethical issues.

What do you think should go in the blanks?

According to the American Psychological Association, ___% of all psychological research involves the use of animals.

90% of research involving animals uses ________ and _____.

__ % of animals used are primates.

8

birds

rodents

5

Gene research Mice have been used to find out how genes affect behaviour.

What are the advantages of using mice?

Breeding: mice breed very quickly, so inheritance can be investigated much quicker than in humans

Similarity: The arrangement of genes along their chromosomes is similar enough to humans to be meaningful.

GenesMice have been used to investigate the effect of genes of deafness.

Rats have been used to study Parkinson’s disease.

Researchers use drugs to replicate the symptoms of Parkinson’s disease, and then use gene therapy to reverse the symptoms.

The Nervous SystemRats have been used in investigations on the effects of antipsychotic drugs on brain structure, and on the nervous system within the brain. The changes they have discovered are:

The Striatum: increased in size due to increased blood flow

Glial cells: Increased density in the prefrontal cortex

Synapses: Increased number of synapses and changes in the synapses

The Nervous SystemMice have been used to investigate changes in ________________ when they were put under stress.

Stress in an area that is often studied using animals.

Why?

neurotransmitters

Studying functions of the brainResearch has been carried out into the way that antipsychotic drugs affect the brain and its nervous system. Most of the research has been carried out on rats and the findings generalised to humans.

However, the research needs to be replicated in human because of the differences in brain structure and function between rats and humans. MRI scans can be used for this

Studying functions of the brain

As far back as 1950, Lashley was investigating brain function in rats by using ablation (removing part of the brain).

He systematically removed parts of the rat’s brain to see what affect it had on memory.

Studying functions of the brain

Rats have also been used to investigate the effects of sleep deprivation.

The rats not only became distressed, but died because of the deprivation.

Nagaraja & Jeganathan (2003)

Examined the effects of acute

and chronicconditions of overcrowdingon free choice ethanol intake

in rats

Aim: To examine the effects of overcrowding on ethanol intake in rats

Method: A lab experiment with independent measures and two conditions

Subjects: Groups of male albino rats

Conditions:Acute stressed - Overcrowded for 6 hours a day for a week

Chronic stressed - Overcrowded continuously for a week

Both conditions had access to ethanol as well as other liquids

The intake for each group was measured

Results:

Chronic stressed group showedincrease in ethanol intake andethanol preference over otherliquids.

EvaluationRelatively small

and easy to handle

The brains of animals are not the same as

humans: results may not be generalisable

Some animals have very short gestation periods and short reproductive

cycles

Their genetic structure is not the same as humans:

results may not be generalisable

Pro-speciesism suggests that we ought to do all we can to protect our

own species

Animals in experiments are not in their natural

surroundings, and therefore distressing

conditions

Evaluation

Some animals (mice etc) have a similar brain structure to humans

Human lives are complex and factors rarely

occur in isolation

Drugs have been developed that could

otherwise not have been developed.

Animals should be treated ethically . They are not sufficiently different from

humans to be treated as objects

Some animals (mice, rats etc) have a short lifespan

(2 years)

Some procedures have to be carried out

daily

Some diseases (Parkinson's) have to be replicated in

animals using drugs, and so may not be the same as the

disease itself. Therefore, studies might lack validity

Evaluation –

The knowledge obtained may also improve the lives of the species being tested

on.

Some procedures require accessing

specific parts of the brain that might then

be damaged.

Some procedures require strict control over the

environment

Using animals may not be

credible

Procedures can be carried out on humans

that can not be done on animals. E.g. ablation

and leisoning

Many animals feel

pain

TaskOrganise the statement slips into arguments for and against using animals for research.

Consider which arguments are practical and which are ethical

Arguments for and against using animals or humans

for research

4

Against

Practical reasons ?

Ethical Reasons ?