Bio explanation - depression Flashcards
What are monoamines?
A group of neurotransmitters - dopamine, serotonin and noradrenaline
Function of noradrenaline?
alertness, concentration, energy, focus
Function of dopamine?
pleasure, motivation, mood
Function of serotonin?
store and recall memories, mood regulation, relaxation
What is monoamine oxidase?
A chemical which breaks down monoamines in the synapse
What is the monoamine oxidase hypothesis?
An imbalance of monoamines causes depression symptoms. The imbalance comes from monoamine oxidase breaking down too many monoamines in the synapse, meaning we aren’t getting enough monoamines.
How were
What are monoamines?
group of neurotransmitters - serotonin, dopamine and noradrenaline
What is monoamine oxidase?
A chemical which breaks down monoamines in the synapse
What is the monoamine hypothesis?
imbalance of monoamines causes depression - imbalance is caused by monoamine oxidase breaking down too many monoamines
What is the function of noradrenaline?
alertness
What is the function of serotonin?
mood regulation
What is the function of dopamine?
pleasure
How was monoamine oxidase discovered as a link with depression?
Treatment for tuberculosis - increased monoamine production and relieved depression
Which NT regulates the others?
serotonin
What is the receptor sensitivity hypothesis?
Serotonin receptors become hypersensitive - body produces less serotonin to compensate for this - overcompensation causes too little serotonin in body
What is the BDNF hypothesis?
low levels of BDNF in hippocampus and prefrontal cortex are found in those with depression - lower the level, the more severe the symptoms
How does stress link to the BDNF hypothesis?
Research shows that stress may cause the gene which produces BDNF to switch off - NT not growing or functioning properly, which can cause depression
Strengths of bio explanation:
- research evidence - Wender and Klein - gave drug to animals which reduces noradrenaline levels and found that they were sluggish and inactive
- validity - SSRI’s, which increase serotonin levels, have shown to decrease symptoms of depression
Weaknesses of bio explanation:
- generalisability - research carried out on animals - cannot extrapolate results onto humans
- WHO discovered that antidepressants work for 60% of people - not 100%, suggesting other causes
