Depression Neurobiology Flashcards
What is the ICD-10 criteria for depression?
2 of:
Depressed mood, anhedonia, Anergia, diminished activity, fatigue
AND
3 of: reduced consciousness, low self-esteem, ideas of guilt, pessimism, self-harm, disturbed sleep, reduced appetite
for at least 2 weeks
What is the suicide rate in the UK?
0.01%
How does depression reduce life expectancy?
8-15 year reduction for men
10-18 years for women
Which scales can be used to assess depression severity?
MADRS
17-item Hamilton
Beck Depression Inventory
Which treatment is most effective in mild illness?
CBT
How should anti-depressant trialling be performed in patients?
Prescription of specific drug above a specific dose for a minimum of 6 weeks
With a reasonable certainty of compliance
Which 5 systems is research based around?
Negative valance - fear, anxiety, loss
Positive valence - reward, habit formation
Cognitive - attention, memory and control
Social - attachment, communication, perception
Arousal - sleep/wake cycle
What does the positive valence system involve?
Mesolimbical and cortical DA systems
Amygdala - learning
Anterior cingulate - attention and response
Orbitofrontal cortex - rule and reward
What does the negative valence system involve?
Endogenous opioid system Ascending 5HT system Stress transmitters Amygdala central ucleus PAG Hippocampus
What is the main purpose of the negative valence system?
Promote survival in threath
How does the positive valence system play a role in depression?
Can’t identify/seek out reward as efficiently so less contact with reward
Then less overall behaviour, especially in typically rewarding activity (sex and eating)
Describe amygdala activity abnormalities in depression
Increased
How is the hippocampus altered in depression?
Volume reduction which correlates with duration of illness
Sheline et al 1996
Schmaal et al (big study)
10 year illness can equate to how much loss of hippocampus?
30%
Which type of memory is then impaired in depression?
Spatial memory
