Lec 71 Bio basis of psychiatric disease Flashcards Preview

Brain And Behavior Exam 4 > Lec 71 Bio basis of psychiatric disease > Flashcards

Flashcards in Lec 71 Bio basis of psychiatric disease Deck (18)
Loading flashcards...
1

What do we know about etiology/pathophysiology of psychiatric disorders?

- etiology unknown
- limited understanding of pathophysiology

2

What is basis of how we diagnose psychiatric disease?

based on clinical observation and symptom description
= descriptive and not etiologically based

3

What is RDoCs?

research domain criteria project
= focus on specific domains rather than traditional diagnostic categories
ex: negative valence systems; positive valence systems; cognitive systems; systems for social processes; arousal/regulatory processes

4

What is purpose of functional neuroimaging?

measure regional cerebral blood flow
measure glucose, oxygen metabolism
image receptors/transporters/NT systems

compare individuals at rest vs engaged in specific task

5

What are limitations of neuroimaging?

limited by physical properties of recording system and constraints of brain
small sample size = hard to apply to general population
expensive

6

What is the MAO deficiency hypothesis?

acute increase in synaptic MOAs by antidepressants produce 2ndary neuroplastic changes that involve transcriptional and translational changes

7

What is the DA hypothesis?

overactivity of DA neurons in mesolimbic pathway may mediate positive symptoms of psychosis

underactivity in mesocortical DA path may mediate negative, cognitive, affective symptoms of schizophrenia

8

What is mech of schizophrenia glutamate dysfunction?

hypofunction of NMDA glutamate receptor --> fail to put inhibitory brake on DA in limbic system

9

What is mech of MDD glutamate dysfunction?

chronic stress --> excess glutamate --> atrophy and death of neurons and glial cells

10

MDD:
- what can you see on structural imaging?
- what can you see on functional imaging?
- what change in NT?

structural: decreased volume of hippocampus PFC/OFC/ACC amygdala

functional: increased activity OFC/amygdala; ACC activity correlates with treatment response

NT: 5HT receptors altered

11

Schizophrenia:
- what can you see on structural imaging?
- what change in NT?

structural: enlarged ventricles, grey matter loss in dlPFC

NT: presynaptic DA synthesis and storage --> hyperactivity of DA in mesolimbic; hypoactivity in mesocortical

12

Social phobia: what can you see on functional imaging?

amygdala hyperactivity in response to harsh faces

13

Alzheimers: what can you see on functional imaging?

diagnositc amyloid deposition

14

What is major neurobio theory for pathogenesis of MDD?

MOAs, glutamate, BDNF

decreased cortical control over limbic output
increased cortisol
impaired plasticity

15

What is major neurobio theory for pathogenesis of panic disorder?

abnormally sensitive fear network including amygdala, PFC, insula, thalamus

decreased sensitivity in GABA system

16

What is major neurobio theory for pathogenesis of PTSD?

overactive HPA axis due to decreased cortisol

increased NE/autonomic responsiveness --> enhanced encoding of trauma memories

17

What is major neurobio theory for pathogenesis of schizophrenia?

hyperactivity of mesolimbic vs hypoactivity of mesocortical DA paths

18

What is major neurobio theory for pathogenesis of autism?

alterations in neuro-developmental process [neuron proliferation, migration, dendritic sprouting, apoptosis, etc]