Week9- Disorders Flashcards
Animal models of human disorders must have what three things?
Face validity
Construct validity
Predictive validity
Face validity
How well does the animal model resemble human disorder
A reasonable outward representation of a disorder (ie: behavioral phenotype matching the symptoms of the disorder)
Construct validity
Is the underlying mechanism of the disorder the same in the animal model of the human condition? Necessary for developing therapeutic interventions
Predictive validity
Does an intervention lead to the expected outcome reliably
The ability to Show a close relationship between test results prior to and after the manipulation in question
What was discovered in 1888 in relationship to thyroid hormones?
Discovered that depressed people tend to have low thyroid function
There is some evidence that depressive symptoms are alleviated by what?
TRH treatment
What can TRH lead to?
Blunted or enhanced TSH in depressed individuals- greater variation
What did the one study in elderly adults find?
Found a correlation between age related decline in thyroid function and mood
What are thyroid hormones used in conjunction with?
With antidepressants to accelerate the clinical response
HPT axis
Hypothalamus releases TRH (+) to the anterior pituitary. Anterior pituitary releases TSH (+) to the thyroid. The thyroid releases T4 and T3 (+) to increase metabolism as well as inhibit the anterior pituitary and hypothalamus from releasing more TRH and TSH
What is disrupted in 50% of MDD patients?
HPA negative feedback and excessive cortisol production
Which axis is impaired in depressed patients? Why?
The negative feedback features of the HPA axis appear to be impaired in depressed patients because blood cortisol concentrations are often higher in depressed people than non-depressed people
What does Dexamethaxone (DEX) do?
Inhibits the normal circadian patterns of cortisol secretions on the first day of treatment
