major depressive disorder Flashcards
affective
symptoms of MDD
sadness, helplessness, loneliness, anxiousness, numbness
cognitive
symptoms of MDD
- low self-esteem
- pre-occupation with failure
and self-blame
motivational
symptoms of MDD
- difficulties with task initiation
- impaired performance
- difficulty with making decisions
physiological
symptoms of MDD
loss of appetite
- weight and sleep instability
- fatigue
- loss of libido
- pre-occupation with personal health problems
APMS (2014)Adult Psychiatric Morbidity Survey [England]:
- One in six (17%) met the criteria for a common mental disorder (CMD)
- One in five women (19%) reported CMD symptoms, compared with one in eight men (12%). 10% of women reported severe symptoms compared to 6% of men
- The trend has been upward for some time
- CIS-R (Clinical Interview Schedule):
- Scoring:
> 12: Symptoms warrant clinical recognition
>18: Symptoms severe, require intervention
genetic vulnerability of MDD
i. 1.5-5 times greater occurrence among 1st degree relatives than in general population
ii. Twin Studies: 48% MZ, 42% DZ concordance
biochemical vulnerability of MDD
iii. Higher vulnerability of women, different hormone cycle
iv. Gene-carrier effect (female prone to depression, male prone to alcoholism)
serotonin on norepinephrine and dopamine systems
serotonin system regulates norepinephrine and dopamine systems, and low levels of serotonin leads to mood deregulation
- Serotonin system as a mood regulator
- Regulates norepinephrine and dopamine activity
- Depletion of serotonin results in deregulation of norepinephrine and larger mood fluctuation
how to MAO inhibitors work at the synapse
(e.g., Nardil)
• Inhibit the breakdown on monoamine neurotransmitters (norepinephrine and serotonin) in the synaptic cleft
• Side effects: blood pressure, drowsiness/headache, fatigue, anxiety, mood shift, weight gain, sexual dysfunction, drug and food interactions (cheese, yoghurt, beer, etc.)
how to Tricycles inhibitors work at the synapse
e.g, Tofranil [imipramine]
• Block reuptake of monoamines into presynaptic cell
• Side effects: dry mouth, sweating, constipation, blurry vision
how to SSRIs inhibitors work at the synapse
- Specifically block serotonin reuptake
* Side effects: anxiety/agitation, digestive problems, dizziness, dry mouth, sweating, low libido
the link between stress and depression
- Early childhood adversity or abuse can lead to lasting difficulty in combating the effects of stress
- In animals, lasting elevation in stress response has been shown following temporary early-life trauma
- High levels of stress can damage the hippocampus
- Impairs down regulation of stress response
- Impairs memory
support of the role of stress regulation in depression
• Brain imaging studies are showing negative effects on the hippocampus of people with depression
Cole et al. (2010)
the implications of the finding that early life stress in animal models can lead to permanent changes in stress levels
In animals, lasting elevation in stress response has been shown following temporary early-life trauma
serotonin depletion
Serotonin levels can be reduced artificially by introducing an agent that depletes tryptophan (which is used in serotonin synthesis). When this is done with people who are in remission from depression, they can experience a relapse in their symptoms. This suggests that lower serotonin levels can be a causal agent in the onset of depression. However, the story is more complicated than this.
When the experiment is done with people with no personal or family history of depression, no mood changes are found due to serotonin depletion. So, lower serotonin levels won’t bring about depressive symptoms in everyone.
Anxiety-Alcohol-Depression vicious cycle
red, green and blue routes
red route
shows anxiety as the entry point. An easily available way to reduce anxiety is to numb oneself with alcohol. Large quantities of alcohol have a depressive effect on the nervous system. This impacts motivation and productivity, which end up increasing anxiety. Meanwhile the body develops tolerance for alcohol, so more alcohol is necessary to get the same numbing effect
green route
shows perhaps the most insidious route into this vicious cycle. Frequent intake of large quantities of alcohol, perhaps as a social ritual, starts to depress the nervous system (where there was no dysfunction to begin with). Once depression kicks, the person starts to become anxious as well. This increases the need and attachment to heavy drinking as a means of dampening anxiety.
blue route
shows the cycle that can begin with, say, stress-induced depression. The state of depression brings with it personal non-coping and under-performance, which in turn elevates anxiety levels. At this point, if alcohol is chosen as self-medication, then it succeeds in deepening depression.
learned helplessness
- Responding to improve things is ineffective
- Formed through specific inescapably negative experiences
- Become all-encompassing through stimulus generalization
- Experimental results:
- Escapability and helplessness
- Explanatory style
Seligman’s shock experiment
Escapability & helplessness
• Escapable shock => Escapable shock : Tries to escape
• No shock => Escapable shock: Tries to escape
• Inescapable shock => Escapable shock : Doesn’t escape
internal attributions
blame the self, external ones find causes outside the self.
stable explanations
imply that the reason for the outcome are persistent as opposed to transient (unstable).
global causes
are broad reasons for negative outcomes whereas specific causes refer only the current event or event type.
internal-stable-global explanation
places the highest, most resilient level of blame on the self. The external-unstable-specific explanatory style has the least impact on how the self is viewed. The other combinations fall in between.
what is BECK triad?
- Assume personal defectiveness
- Negatively interpret events
- No hope for the future
- DEPRESSIVE REASONING:
- Arbitrary inference leading to unsupported conclusions
- “My work is not valued”
- “Nobody likes me”
arbitrary inference
Drawing a negative conclusion without a tight argument.
selective abstraction
Picking up something negative and then broadening it into a more general principle.
over generalisation
Again, going from negative instances to broad negative views.
magnification of negatives, minimisation or positives
Highlighting or over-estimating the importance of the negative aspects of experience
personalisation
Unwarranted levels of holding the self responsible for negative things.
