Depression Flashcards
What is neurology?
Neurology is a branch of medicine, diagnosis and treatment of disorders that affect the mind or psyche
What is human behaviour the product of?
Human behaviour is the product of brain activity
What is the brain the product of?
The brain is the product of genetics and environment
What are the characteristics of affective disorders?
Disorders of mood rather than thought/condition
What are the 2 types of depression?
- Unipolar depression
2. Bipolar depression
What happens in unipolar depression?
Mood swings in one direction
What is the most common depressive illness?
Unipolar depression
What percentage of cases are reactive(environmentally induced)?
75% cases are reactive
What percentage of cases are endogenous(Genetic)?
25% cases are endogenous
What happens in bipolar depression?
Oscillation between depression and mania
What is mania?
Mania is excessive exutenance, enthusiasm, self confidence
When is the onset of bipolar depression usually?
Onset usually in adult life
What tendency does bipolar depression have?
Strong hereditary tendency
What is a depressive disorder?
Is a low state marked by significant levels of sadness, lack of energy, low self-worth
What is major depressive disorder?
Is a severe pattern of depression that is disabling and is not caused by factors such as drugs or a general medical condition
What is dysthymic disorder?
Is similar to major depressive disorder but less severe and more long lasting
What do doctors use to diagnose patients with depression?
Doctors use DSM-IV to diagnose patients with depression
What are the emotional symptoms of depression?
- Apathy, pessimism, negativity
- Low self esteem
- Loss of motivation
What are the biological symptoms of depression?
- Reduced activity
- Loss of libido
- Sleep disturbance
- Loss of appetite
In what gender is depression more common in?
Depression more common in females than males
What are the factors to consider in depression?
- Suicide
- Comorbidity
What medical conditions usually comorbidity with depression?
- Terminal illness
- Chronic illness
- Thyroid dysfunction
- Parkinson’s
- Anxiety
What causes depression according to the monoamine theory of depression?
-Caused by deficit of monoamines in the brain
What evidence is there tested on mice for the monoamine theory of depression?
- Mice were injected with reserpine which depletes the brain of NA and 5-HT
- This induces depression
What is evidence against the monoamine theory of depression?
- Most antidepressant drugs take several weeks for therapeutic effect
- Cocaine blocks amine uptake but has no antidepressant effect
- Decrease on 5-HT in dipolar is linked to aggression rather than depression
What causes depression according to the neuroendocrine theory?
-Caused by hypersensitivity of the HPA axis
What is the evidence for the neuroendocrine theory?
- There’s hyperactivity of the HPA meaning there’s increased [cortisol]plasma in depressed patients
- There’s reduced negative feedback from the hippocampus
What happens in the brain in a depressed patient according to the neuroendocrine theory?
-High activity of amygdala stimulates the HPA increasing release of cortisol
-High activity of the hippocampus will suppress HPA axis activity
~Cortisol acts on cortisol receptors on the hippocampus
to inhibit HPA axis
What does hyperactivity of the amygdala or hypoactivity of the hippocampus lead to?
Hyperactivity of the amygdala or hypoactivity of the hippocampus effects levels of cortisol which can lead to depression
What is glucocorticoid receptor gene expression regulated by and how?
Glucocorticoid receptor gene expression is regulated by early experience
- Tactile stimulation just after birth activates 5-HT pathways to hippocampus
- 5-HT triggers long lasting increase in expression of glucocorticoid receptor gene
- This increases glucocorticoid receptors in hippocampus
What do SSRI’s do to glucocorticoid receptors?
SSRI’s increase glucocorticoid receptors in hypothalamus
What is depression caused by according to the neuroplasticity and neurogenesis theory?
Depression could be caused by neuronal loss or decrease of neurogenesis or decreased activity in hippocampus and prefrontal cortex
What do antidepressants and ECT do in the hippocampus and prefrontal cortex?
Antidepressants and ECT promote neurogenesis in these regions
What does 5-HT during development?
5-HT promotes neurogenesis during development
What is ECT and what does it do?
ECT is localised electrical stimulation
-There’s evidence of neurogenesis
What stage of depression is psychotherapy for and what does it do?
Ideal for mild to moderate depression
-Overcomes negative views
What do all drugs used to treat depression increase?
All drugs used to treat depression increase 5-HT or NA
What do tricyclic antidepressant drugs do?
These inhibit 5-HT and NA transporters, therefore increase 5-HT and NA levels in cleft
What do fluoxetine antidepressant drugs do?
These inhibit 5-HT transporter, increasing concentration of 5-HT in cleft
What do MAO inhibitors do?
MAO inhibitors inhibit MAO, therefore preventing the breakdown of monoamines
What does reboxetine do?
Inhibits NA selective reuptake
