biological explanation of depression

Question 1

what is normality

Answer 1

a properly functioning nervous system

Question 2

what are the two biological explanations

Answer 2

the genetic argument

the neurological argument

Question 3

what is the neurological argument

Answer 3

• depression is a result of reduced levels of certain neurotransmitters e.g. serotonin
• dopamine may also play a part
• serotonin is said to have a calming effect on the brain as it inhibits neural firings. low levels of the neurotransmitters serotonin lead to depression as this calming effect is not present and mood becomes unstable
• noradrenaline is a neurotransmitter released during in the sympathetic branch of the nervous system. increases heart rate and blood pressure. low levels causes drowsiness, lethargy.

Question 4

evidence to support the neurological argument

Answer 4

• Wender and Klein
• Lemonick
• Teuting et al
• Cooper

Question 5

what did Wender and Klein find

Answer 5

• Wender and Klein administered a drug to non-human animals which reduced the levels of noradranaline produced
• the animals become sluggish and inactive, showing symptoms associated with depression
• symptoms alone - not necessarily actual depression
• have to infer how animals feel from their behaviour

Question 6

what did lemonick find

Answer 6

put forward the fact that drugs given to treat depression work by increasing the availability of noradrenaline and or serotonin
the fact that antidepressants are commonly prescribed and are successful in many cases to treat depression supports the idea that it has neurological causes
drugs treatment don’t treat the biological cause

Question 7

describe MAOIs

Answer 7

• using MAOIs to treat TB they discovered that patients become remarkably euphoric
• monoamines are serotonin, dopamine, noradrenaline
• SCHILDSKRAUT believed that too high a level of noradrenaline led to mania and too little depression
• PRANGE a deficit in serotonin permits the symptoms of depression
• changes in serotonin levels affect the nature and intensity of the symptoms
• activity is decreased = depression
• both serotonin and noradrenaline levels change in mood disorders
• there is a serotonin deficit in depressives = it is genetic
• noradrenaline increase = mania
• noradrenaline decrease = depression

Question 8

describe SSRIs

Answer 8

• drug treatments that concentrate on raising serotonin levels do improve the depressed mood in the majority of patients
• newer anti-depressants are actually targeted at both serotonin and noradrenaline and are even more effective in treating depression

Question 9

evaluation of the neurological argument

Answer 9

• not all depressants with depression will have low serotonin levels
• anti-depressants such as MAOIs increase the levels of noradrenaline and serotonin within minutes however they have no effect on mood for many weeks. this suggests that they are not working simply by increasing the levels of chemical in the brain. suggests NTs as a cause of depression is more complex
• not all depressives show reduced levels of these neurochemicals
• not all patients benefit from drug treatment
• are other biological factors involved? diet? cortisol?
• SSRIs raise levels of serotonin and have a well-established antidepressant effect

Question 10

what are the gender differences in the neurological argument

Answer 10

• DIKSIC et al found that men make 52% more serotonin than women - could make men far less prone to depression than women
• brain scans so scientifically credible

Question 11

what is the genetic argument

Answer 11

the genetic argument states that depression occurs as a result of the genes we inherit from our parents and that some of us will have an innate predisposition to becoming depressed generally, there is a positive correlation between genetic relatedness to a person with depression and rates of depression