Lecture 8: Affective disorders 1: depression Flashcards
What is central to depression?
Depressed mood and or loss of pleasure in most activites
What is severity of depression determined by?
The number and severity of symptoms
What are the 2 diagnostic systems for depression?
ICD- 10 and DSM-5. Symptoms should be present for atleast 2 weeks and each symptom should be present at sufficient severity for most of every day.
What is ICD 10?
- Manic episodes
- Bipolar disorder
- Major depressive disorder, single episode
- Major depressive disorder, recurrent
- Persistent mood disorders
- Unspecified mood disorder
What is bipolar I and bipolar II?
I- The classic form where a person has had at least one manic disorder
II - The person has never had a manic episode, but has had at least one hypomanic episode and at least one period of significant depression
There is a strong genetic component
What is euthymia?
Phases in between mania and depression
What are the symptoms of major depressive disorders?
Key symptoms:
- persistent sadness or low mood
- loss of interests or pleasure
- fatigue or low energy
Associated symptoms:
- distrubed sleep
- poor concentration or indecisiveness
- low self confidence
- poor or increased appetite
- suicudal thoughts or acts
- agitation or slowing of movements
- guilt or self blame
Symptoms should be present for atleast 2 weeks and each symptoms should be present at sufficient severity for most of every day
What defines the degree of depression?
- Not depressed <4 symptoms
- Mild depression 4 symptoms
- Moderate depression 5 or 6 symptoms
- Severe depression >7 symptoms, with or without psychotic symptoms
What is the monoamine hypothesis?
Depression occurs due to decreased levels of amine in the CNS.
Noradrenaline binds to alpha receptors where it has negative and positive effects on gene transcription
What are the pathophysiology of depression
- Monoamine hypothesis of depression
- Glucocorticoid hypothesis of depression
-Neurogenesis hypothesis of depression - Glutamate hypothesis of depression
- GABA hypothesis of depression
What is the glucocorticoid hypothesis of depression?
Includes the stress response. Uses the HPA Axis. Releases glutamate and also cortisol which has effects on transcription which can lead to neuronal apoptosis and depressive symptoms
What is the glutamate hypothesis?
Excessive glutamate leads to excessive activation of NMDA receptors, leads to neuronal apoptosis
What is synaptic transmission?
High speed and precise eg glutamate
What is volume transmission?
Temporally slower, anatomically broader - acts on multiple synapses - not as specific eg monoamines
Where in the brain do neurotransmitters originate?
Noradrenergic system - locas coeruleus. They pass all around the brain
