unipolar depression Flashcards
1
Q
define unipolar depression
A
unipolar depression is an affective (mood disorder) characterised by sadness, loss of interest or enjoyment and marked tiredness
2
Q
how to use DSM-5 and ICD-10 to diagnose schizophrenia
A
symptoms of depression need to be present for at least 2 weeks
3
Q
what are the 3 symptoms of unipolar depression
A
- psychological (cognitive) symptoms
- physical (bodily) symptoms
- social (behavioural) symptoms
4
Q
describe psychological (cognitive) symptoms of unipolar depression
A
- feeling hopeless and helpless
- having low-self esteem
- feeling guilt-ridden
- difficulties with memory and concentration
- finding it difficult to make decisions
- feeling anxious or worried and having suicidal thoughts
- harming yourself
5
Q
describe physical (bodily) symptoms of unipolar depression
A
- change in appetite or weight (usually decreased)
- constipation (digestive problems)
- unexplained aches and pains
- lack of energy or lack of interest in sex
- for women changes to mensural cycle and disturbed sleep patterns
6
Q
describe social (behavioural) symptoms of unipolar depression
A
- not going to or doing well at work
- taking part in fewer social activities
- avoiding contact with friends
- neglecting your hobbies and interests
- having difficulties in your home and family life
7
Q
describe the features of unipolar depression
A
- depression affects 3.5 million people in the UK
- depression is twice as common in women as in men
- depression is most common in ages 25-44 years old
8
Q
describe the monoamine depletion hypothesis of depression
A
- monoamines are a group of neurotransmitters that contain amino acids and they regulate mood
- depression is caused by abnormally low levels of the monoamine neurotransmitters: serotonin, noradrenaline and dopamine
- these are good candidates because of their roles in regulating functions of the brain’s limbic system which is the brain’s emotional centre which has many connections to the frontal cortex
- serotonin (5-HT) - regulates the activity of noradrenaline and has a role in sleep, appetite, memory and sexual behaviour, if levels drop noradrenaline can fluctuate
- noradrenaline - related to alertness and energy, low levels are linked to anxiety
- dopamine - provides attention and reward, low levels are linked to a lack of pleasure
9
Q
describe the receptor sensitivity hypothesis of depression
A
- depression is caused by changes in the sensitivity of postsynaptic receptors
- the normal response of receptors to depletion in neurotransmitter stimulation is up-regulation
- neurones compensate for the reduction in neurotransmitter stimulation by increasing the sensitivity of receptors and producing more of them
- in depression serotonin receptors become supersensitive causing neurones to respond as if they are overstimulated so they produce less serotonin
10
Q
describe the brain-derived neurotrophic factor of depression
A
- the brain-derived neurotrophic factor is a chemical that feeds neurones the nutrients they need to survive, grow and function efficiently
- so it plays a key role in neuronal plasticity (the ability of the brain to form new synapses)
- levels of BDNF in the hippocampus and prefrontal cortex are abnormally low in people with depression
- the BDNF hypothesis allowed researchers to link depression with stress, this is because the gene for BDNF may be switched off under stress leaving the neurones fed by BDNF vulnerable to atrophy or apoptosis
11
Q
what are the advantages of the biological explanation of depression?
A
- a strength is that there are two main sources of evidence for BDNF in depression
- some studies like Sen have found a negative correlation between abnormally low blood serum levels of BDNF and the severity of depressive symptoms
- post-mortem studies of the brains of people who have depression have found abnormally low levels of BDNF in the hippocampus and prefrontal cortex
- shows a clear association between BDNF level and depressive symptoms
12
Q
what are the disadvantages of the biological explanation of depression
A
- weakness is that the theory is based on treatment aetiology fallacy
- historically the biochemical explanations of depression began with observations of how antidepressant medication affects depression
- for example, it was noted that postsynaptic receptors were down-regulated by antidepressants that increased serotonin
- researchers assumed that if a biochemical treatment improved the symptoms of depression then this implied that depression must have a biochemical cause
- this is not true because an antidepressant drug could work by correcting a biological process that is disturbed by a psychological factor like stress
- so the treatment is biological but the cause is psychological
13
Q
what is the application of the biological explanation of depression?
A
- as our understanding of the biochemistry of depression develops, so do the drugs used to treat it
- recent drug treatments target both serotonin and noradrenaline levels as opposed to only serotonin
- other neurotransmitters like GABA and dopamine are attracting interest as targets for medication
- BDNF offers another route involving a different type of biological treatment like transcranial magnetic stimulation of the brain
- treatments based on the biological explanation may improve the quality of life of depressed people and reduce stress
14
Q
list the 3 examples of faulty cognitions suggested by Beck’s cognitive model
A
- the negative cognitive triad
- cognitive biases
- negative schemas
15
Q
explain the cognitive triad in the non biological explanation of depression
A
- people with depression have a negative view of self, the world and the future
- negative views are automatic in depressed people
- people act on these negative views via destructive behaviour that causes them to fail at things and struggle in relationships
- this convinces them that their core beliefs are right
