S12) Mood Disorders Flashcards
Patients with depressive disorders usually have the symptoms continually for 2 weeks.
What are the core symptoms of depression?
- Low mood
- Lack of energy
- Lack of enjoyment and interest (anhedonia)
Apart form the core symptoms, what are other features of depressive disorders?
- Depressive thoughts
- Biological symptoms (loss of weight, lack of sleep, etc)
Compare and contrast the difference between a ‘normal’ adjustment reaction and clinical depression in terms of the following:
- Symptom onset
- Energy
- Sleep pattern
- Appetite
- Emotions
There are many illnesses that can cause depressive symptoms.
Provide five examples
- Hormone disturbance e.g. thyroid dysfunction
- Vitamin deficiencies e.g. vitamin B12
- Heart and lung diseases
- Blood vessels malfunction
- Kidney disease
Identify three brain structures involved in depressive symptoms
- Limbic system memory n emotion
- Frontal lobe emotion
- Basal ganglia motor movements, direct n indirect pathway
Identify some structures in the limbic system
What are the functions of the limbic system?
- Emotion
- Motivation
- Memory
Identify some functions of the frontal lobe
- Motor function
- Language (Broca’s area)
- Attention
- Memory
- Mood
The inferior portions of the anterior part of the frontal lobe are involved in the generation and expression of emotions, probably via connections with the amygdala
Identify some psychological functions of the basal ganglia
- Emotion
- Cognition
- Behaviour
changes in the basal ganglia volume and activity is seen in mood disorders
What are the two main neurotransmitters for depressive disorders?
- Noradrenaline
- Serotonin (brainstem → cortical areas in limbic system)
→ both of these are monoamines
Identify some other neurotransmitters which are important in psychiatric conditions
- Dopamine
- Acetylcholine
- GABA
- Glutamate
What are the functions of noradrenaline in the brain?
- Mood
- Possible role in behaviour (arousal and attention)
- Implicated in memory functions
Describe the synthesis and transport of noradrenaline
Noradrenaline is made in the locus coeruleus in the brainstem and transported to several areas of the cortex
What is the role of serotonin in the brain?
- Sleep
- Impulse control
- Appetite
- Mood
Describe the synthesis and transport of serotonin
Serotonin is produced in the brain stem (Raphe nuclei) and transported to cortical areas and limbic system
evidence for reduced serotonin in depression
o Drugs that increase serotonin in the brain treat depression
o 5HIAA (a metabolite of serotonin) is low in the CSF of patients with depression
o Tryptophan (a precursor of serotonin) depletion causes depression
(It might be the case that antidepressants act to change the levels of other neurochemicals, maybe even stimulating neurogenesis in the hippocampus through growth factors such as brain derived neurotrophic factor)
evidence of reduced noradrenaline in depression
o Drugs that increase levels of noradrenaline treat depression
o Patients who have recovered from depression but still have low levels of noradrenaline are at higher risk of relapse
o Post-mortem studies suggest lower levels of noradrenaline in the brains of those with depression
evidence of reduced noradrenaline in depression
o Drugs that increase levels of noradrenaline treat depression
o Patients who have recovered from depression but still have low levels of noradrenaline are at higher risk of relapse
o Post-mortem studies suggest lower levels of noradrenaline in the brains of those with depression
Which three factors cause people to become clinically depressed?
- Predisposing factors
- Precipitating factors
- Perpetuating factors
Identify some predisposing factors of depression
- Genetic
- Childhood experiences
- Female gender
Identify some childhood experiences causing depression
Causation is cumulative:
- Quality of attachment
- Quality of parental relationships
- Loss of a parent
- Bullying
In research woman are consistently found to be more likely to suffer from an affective disorder.
What are the possible reasons for this?
- Social and occupational role (marriage, child care)
- Men are more likely to distract themselves from depressed mood
- Woman are more willing to admit to being depressed
Social stressors are identified as a perpetuating cause for depression.
Provide some examples of this
- Social economic status
- Unemployment
- Financial hardship
- Isolation from family and friends
Central to the available treatments is that the function of the brain is restored.
How can depression be treated?
- Medication – direct effect on the biochemistry of the brain
- Social and psychological interventions e.g. CBT – measurable effect on the biochemistry of the brain
SSRI → increase the amount of serotonin in the brain and prevent uptake into neurones
Illustrate the relationship between the aetiology and treatment of depression
what are some features of mania
what is mania?
elevated mood and energy levels with racing thoughts
Psychosis may be a feature
Hypomania refers to symptoms that are still clearly manic but don’t necessarily reach full diagnostic criteria for mania
what is Bipolar Type 1
→ most severe type
→ episodes of mania or mania and depression
(you don’t have to be diagnosed with depression to have bipolar disorder)
what is Bipolar type 2
→ episodes of hypomania or hypomania and depression
what are some physical differentials for depression
▪ Hypothyroidism
▪ B12 deficiency
▪ Chronic disease
▪ Substance misuse
▪ Hypoactive delirium
what are some physical differentials for mania
▪ Hyperthyroidism
▪ Delirium (hyperactive type)
▪ Iatrogenic (e.g. steroids)
▪ Infection (e.g. encephalitis, HIV)
▪ Head injury
▪ Intoxication (e.g. stimulants)
describe the Papez circuit (main emotion circuit)
- cortical regions send impulses to the hippocampus
- these impulses are sent to the mammillary bodies via the fornix
- maxillary bodies project to the thalamus and the hypothalamus
- the thalamus projects to the cortex while the hypothalamus projects to the pituitary and autonomics mediating one of the somatic effects
what is the Amygdala
another part of the limbic system,but can be grouped with hippocampus in terms if its connections
what is the papez circuit responsible for
for memory consolidation, where the hippocampus is able to induce long term potentiation in the cortex to lay down long term memory
Treatment for acute mania (bipolar disorder)
→ antipsychotics and mood stabilisers (lithium)
→ keep patients safe so reduced risk to themselves and others
treatment for acute bipolar depression
→ anti-depressants
→ CBT
→
how to manage stability
mood stabiliser (lithium or valproate with or without anti-psyhcotics
→ education CBT
→ consider effects on employment and family support
unipolar depression vs bipolar depression
uni-polar only has one form of depression whereas, bi-polar would have mania and depression
what are some examples of motor disorders to do with he basal ganglia
- Parkinson’s disease
- Wilson’s disease
- Huntington’s disease
which medication is avoided in pregnancy?
Sodium Valproate as it can be teratogenic
which medication should you avoid in Bi-polar
SSRI → as they increase the amount of serotonin and will make bipolar worse
