biochemical explaination of depression Flashcards
what is a monoamine
a neurotransmitter that contains one amino group including serotonin, noradrenaline, dopamine
what is the monoamine hypothesis
suggests there is low levels of monoamines in your brain causing depression
what are the two main brain areas associated with depression
dopamine pathway
serotonin pathway
serotonin role, link and symptoms associated based on nt explanation of sz
role : to control the activity of other nts
link : linked with happiness and reduced anxiety without serotonin we have erratic brain activity which impacts thinking. It is also important for sleep regulation, mood and appetite
symptoms : low levels of serotonin leads to low levels of dopamine and noradrenaline
noradrenaline role and symptoms associated based on nt explanation of sz
role : alertness, energy, anxiety and attention to life
symptoms : low levels can cause drowsiness, low energy, and problems concentrating
dopamine role and symptoms associated based on nt explanation of sz
role : ability to pay attention, motivation, pleasure and sense of reward
symptoms : low levels mean we cannot do these things well
what is monoamine oxidase
an enzyme which causes oxidation and inactivation of monomamines
how is monoamine oxidase linked to depression
people with depression may have high levels of moa which breaks down monoamines too easily/quickly
strengths and weaknesses of biochemical explanation of depression (other theories)
genetics - faulty information processing negative bias leads to negative thoughts
strengths and weaknesses of biochemical explanation of depression (supporting)
:) wender and klein - found non humans that are given drugs that diminish noradrenaline become sluggish and inactive - noradrenaline should do that according to theory
:) lemonick - drugs that treat depression increase brain levels of noradrenaline or serotonin - by taking something that boosts sero, nora and adren it gets rid of symptoms so likely the cause from low levels
strengths and weaknesses of biochemical explanation of depression (conflicting)
:( delgado - depleting monoamines in someones brain does not lead to depression or make it worse - according to theory this should make symptoms worse
:( kirsch - meta analysis showed placebos are just as effective as ssris questioning role of serotonin - the thing drug is doing isn’t necessarily the cause
:( monteleone - the number of things responsible for depression is so wide that any nt deficit is seen as a potential cause - says not just sero, nora and andren are responsible
strengths and weaknesses of biochemical explanation of depression (usefulness)
:) drug treatments - SSRI’s etc work by increasing levels of monoamines in the brain which is effective in treating depression
:( OTOH treatment aetiology fallacy - just because raising levels of moa treats symptoms doesn’t mean low levels were actually the cause
:( reductionist - ignores other factors that may influence development of depression - not full explanation of depression
strengths and weaknesses of biochemical explanation of depression (testability)
:) can empirically measure levels of moa and moa oxidase in the urine so more objective
OTOH :( no cause and effect between levels of moa and depression only correlation so less valid
