19. Depression Flashcards
What type of disorder is depression? (Depression B&B)
An affective disorder
What is anhedonia? (Depression B&B)
The inability to feel pleasure in previously pleasurable activities
How is a major depressive episode characterised? (Depression B&B)
Depressed mood and/or anhedonia plus at least 5 more symptoms, lasting almost every day for two weeks
What are the 8 symptoms associated with depression? (Depression B&B)
- Body weight changes
- Sleep changes
- Motor retardation
- Loss of energy
- Worthlessness
- Guilt
- Inability to concentrate
- Suicidal thoughts
What is the heritability rate of depression if relatives have it? (Depression B&B)
2/3 times more likely
What does the monoamine hypothesis suggest about depression? (Depression B&B)
Symptoms are caused by insufficient activity of the monoaminergic neurons
What are two types of monoamines? (Depression B&B)
- Norepinephrine
- Epinephrine
What is a monoamine? (Depression B&B)
Basic neurotransmitter
What is norepinephrine associated with? (Depression B&B)
noradrenaline
What is epinephrine associated with? (Depression B&B)
Adrenaline
What did Asberg et al (1976) find? (Depression B&B)
Lower levels of 5-HT metabolite 5-HIAA in cerebrospinal fluid of depressed patients
What is reserpine and why was it so influential? (Depression B&B)
- Used to treat blood pressure in mid 20th century
- Side effects were depression
- It blocked the packaging of monoamines (when neuron activated, firing was inhibited)
How do monamine oxidise inhibitors work? (Depression B&B)
They inhibit the breakdown of monoamines in the presynaptic terminal, increasing the proportion of monamines that are taken into the vesicle
What are side effects of monoamine oxidise inhibitors? (Depression B&B)
- Cheese effect (increased tyramine stored in liver)
- Only acceptable is P’s were on a strict no cheese diet
How do tricyclic antidepressants work? (Depression B&B)
Inhibit the reuptake of 5-HT and noradrenaline
How do SSRI’s work? (Depression B&B)
Selective in blocking the reuptake of serotonin (increasing availability at the synaptic cleft)
What does the stress diathesis model suggest? (Depression B&B)
Those who suffer from depression experience serve stress from the environment
What did Bremner (2000) find in evidence for the DSM? (Depression B&B)
Depressed patients have reduced hippocampal volume
What did Sheline (2003) find in relation to DSM? (Depression B&B)
There is a negative correlation between the days of untreated depression and hippocampal volume
What axis of the brain is most relatable to stress and depression? (Depression B&B)
Hypothalamus pituitary adrenal axis
What is the process of HPA activation during stress? (Depression B&B)
- Stressor in environment
- Hypothalamus activated
- Hypothalamus releases CRH
- Anterior pituitary gland activated
- Release of ATCH
- Adrenal cortex stimulated
- Release of cortisol
What happens in situations of chronic stress? (Depression B&B)
Chronic activation of glucocorticoid receptors in the hippocampus
What does chronic activation of glucocorticoid receptors lead to? (Depression B&B)
- Increase Ca2+ entry to neurons
- Too much = excitotoxic (neurons damaged and killed)
How is chronic activation of glucocorticoid receptors related to depression? (Depression B&B)
Hippocampus cannot feedback to limit cortisol production
What is neurogenesis and how is it related to treatment? (Depression B&B)
- Development of new neurons or cells
- Treatments induce neurogenesis
What are neurotrophins important for? (Depression B&B)
The normal developmen of a healthy nervous system
What did Capsi et al (2003) test? (Depression B&B)
Why stressful experiences lead to depression in some individuals but not others
What were the main findings by Capsi et al (2003)? (Depression B&B)
- Those with short/short allele held the highest correlation between stressful events and depression
- Those with the long/long allele held the lowest correlation
What did Lee et al (2004) find? (Depression B&B)
Patients with long/long allele had better long term outcomes from antidepressants that short/long or short/short patients
