Lecture 33- Disorders of thought and mood Flashcards
What is the division of depressive disorders?
- Bipolar affective disorder has two forms: bipolar disorder and cyclothymia (milder manic depression) 2. Major depressive disorder: Major monopolar depression or dysthymia (milder version)
What is the DSM definition of a major depressive episode?
A. Five (or more) of the following symptoms have been present during the same 2- week period and represent a change from previous functioning; at least one of the symptoms is either (1) depressed mood or (2) loss of interest or pleasure.
- depressed mood most of the day, nearly every day, as indicated by either subjective report (e.g., feels sad or empty) or observation made by others (e.g., appears tearful). Note: In children and adolescents, can be irritable mood.
- markedly diminished interest or pleasure in all, or almost all, activities
- significant weight loss when not dieting or weight gain (> 5% of body weight in a month), or decrease or increase in appetite nearly every day.
- insomnia or hypersomnia nearly every day
- psychomotor agitation or retardation nearly every day
- fatigue or loss of energy nearly every day
- feelings of worthlessness or excessive or inappropriate / delusional guilt
- diminished ability to think or concentrate, or indecisiveness, nearly every day (either by subjective account or as observed by others)
- recurrent thoughts of death (not just fear of dying), recurrent suicidal ideation
What feelings are commonly experienced in major depressive episodes?
-In major depressive disorder affective or mood symptoms include depressed mood and feelings of worthlessness or guilt, cognitive and somatic symptoms but also behavioral symptoms including social withdrawal and agitation. -mood symptoms, that affect the way you feel and how other feel about you
What feelings are characteristic of manic depression?
-Manic episodes greatly elevated mood, creativity, profusion of thought and pressured speech. May manifest as grandiosity and confidence or anxiety and aggression. Feeling of increased or limitless energy, including reduced need for sleep. Typically highly distractible, irritable, and exhibiting poor judgment. Extreme mania may include disordered (pyschotic) thought. -the depressive phase alternates with mania when they feel extreme pleasure, confidence, also can manifets as anxiety -limitless energy etc. -distractible, delusions about your own potential
What is the blood flow in the brain of a depressed person?
- too little blood =chronically underactive
- more blood when in depression episode
- overactivity of the system that makes us feel bad
- Abnormally high blood flow abates with resolution of depression, regardless of the treatment (or lack of) associated with remission
What was Robert Schumann’s creativity like during his mania and depression periods?
- in manic depression
- common in people of highly creative people hypomanic= mania, very creative
How was the effect of lithium discovered?
-John Cade, a Melbourne Doctor (and UniMelb graduate) was conducting researching in the 1940’s on the effects of uric acid when he accidentally discovered the mood stabilizing effects of lithium on his guinea pigs. -what if urea level too high= can there be an effect on the nervou system -put more urea in dissolved in lithium= after they were much calmer, no extremes of behaviour -lithium is a mood stabilizers= treatment for manic depression
How is monopolar depression most often treated?(3)
- Electroconvulsive therapy= most effective for some people 2. Psychotherapy= the talking cure 3.Antidepressant drugs: Tricyclics, SSRIs NERIs, Monoamine oxidase inhibitors
What are the antidepressant drugs used for monopolar depression? (4)
1.Tricyclics= not as common 2. SSRIs ( selective seretonin re uptake inhibitors)= most commonly prescribed 3. NERIs(noradrenalin reuptake inhibitors) =affect neurotransmitter transmission 4. Monoamine oxidase inhibitors
Where do drugs interact with neurons?
-Drugs that affect the brain and behaviour (other than those affecting its growth or those having a degenerative or neurogenerative effect) must directly or indirectly affect the excitability of neurons. Interactions with -neurotransmission could occur at numerous places in the biochemical pathways related to neurotransmitter synthesis, storage, release, breakdown, re- uptake and postsynaptic receptor interaction.
Where do drugs that affect mood work?
-when drug work on mood= neural transmission effect -lot of scope for subtle changes -blocking release, blocking transport, blocking enzyme that breaks it down, blocking re uptake -modulating the receptor, occupancy…
Where do the antidepressive drugs act on?
- act at the noradrenalin and serotonin synapses -affect either reuptake, or enzymatic breakdown of monoamines
Where do tricyclics, SSRIs and NERIs act on?
-noradrenaline and serotonin are broken down but also they are up taken by the cell inhibition of its re uptake= prolong its action= it is like you released more
Where do monoamine oxidase inhibitors act on?
-this breaks down the enzyme that breaks them down= so increase in serotonin and noradrenaline
What do MAO inhibitors do?
-MAO is the enzyme responsible for the destruction of all monoamines (Noradrenalin, adrenaline, dopamine and serotonin).
What do MA reuptake inhibitors do? (SSRI, NERI)
-Monoamine reuptake (the other mechanism for limiting the action of monamines at synapses) further supports the idea of impaired monoamine transmission underlying depression.
What does lithium do?
Lithium salts are the third category of drugs used to treat depression, particularly manic depression; their mode of action is not understood but may modulate phosphoinositol second messengers.