Chapter 8: Anxiety and Trauma

Question 1

which brain circuits may be malfunctioning in GAD

Answer 1

amygdala and CSTC

Question 2

Anxiety and fear are regulated by which brain circuit

Answer 2

amygdala centered circuit

Question 3

worry is regulated by which brain circuit

Answer 3

cortico-striatal-thalamic-cortical (CSTC)

Question 4

the affect of fear is regulated by reciprocal connections between which two brain circuits

Answer 4

-amygdala and anterior cingulate cortex
-amygdala and orbitofrontal cortex

Question 5

what regulates motor responses to fear

Answer 5

connections between the amygdala and periaqueductal gray area of the brain stem

Question 6

what causes the endocrine output of fear

Answer 6

connections between amygdala and hypothalamus causing changes in the HPA axis to give a quick boost of cortisol to enhance survival instincts

Question 7

what causes changes to breathing output during anxiety

Answer 7

connections between amygdala and parabrachial nucleus (PBN) in the brainstem

Question 8

autonomic and cardio responses to fear are mediated by what connections

Answer 8

connections between the amygdala and the locus coeruleus

Question 9

how is the hippocampus the internal fear monger

Answer 9

anxiety can be triggered by traumatic memories stored in the hippocampus and activated by connections to the amygdala

Question 10

what is thought to cause worry/obsessions

Answer 10

worry may be d/t overactivation of the CSTC loop originating and terminating in the DLPFC

Question 11

how do benzodiazepines work as medications for anxiety

Answer 11

act as PAMs on postsynaptic GABAA receptors in the amygdala where they blunt fear outputs and enhance the action of inhibitory GABA in the PFC

Question 12

what is the key neurotransmitter that innervates the amygdala as well as elements of the CSTC circuits

Answer 12

serotonin

Question 13

what action makes buspirone an effective anxiety treatment for GAD

Answer 13

5HT1A partial agonism

Question 14

what disorder is treated by buspirone

Answer 14

GAD is the only anxiety disorder it works for

Question 15

where in the brain does buspirone enhance serotonergic activity to reduce worry

Answer 15

in projections to the amygdala, PFC, striatum, and thalamus

Question 16

how fast does buspirone work

Answer 16

delayed onset of action like SSRIs

Question 17

where in the brain does norepinephrine have important regulatory input

Answer 17

amygdala, PFC, and thalamus CSTC circuits

Question 18

what causes the peripheral manifestations of autonomic overdrive

Answer 18

excessive norepinephrine output from the locus coeruleus

Question 19

anxiety symptoms caused by excessive norepinephrine output from the locus coeruleus

Answer 19

central symptoms
reduced information processing in the PFC and CSTC circuits

Question 20

central symptoms of anxiety/fear

Answer 20

nightmares
hyperarousal states
flashbacks
panic attacks

Question 21

what can happen to anxiety symptoms after SNRI initiation and why?

Answer 21

fear and worry can get worse initially until B1-adrenergic receptors are downregulated

Question 22

how does the amygdala “remember” stimuli associated with a fearful situation

Answer 22

it increases the efficacy of glutamate neurotransmission in the lateral amygdala when fearful stimuli is received from the thalamus or sensory cortex. Input is then relayed to the central amygdala where neurotransmission of glutamate is further improved by fear conditioning

Question 23

VMPFC role in fear conditioning

Answer 23

-if VMPFC cannot suppress fear response before it reaches the amygdala fear conditioning results

Question 24

hippocampus role in fear conditioning

Answer 24

remembers the context of the fear conditioning so that fear is experienced when same or associated stimuli is encountered

Question 25

what causes a fear response to be generated or suppressed

Answer 25

input from fearful experience is relayed to amygdala where it is integrated with input from the VMPFC and hippocampus to generate or suppress a fear response

Question 26

what causes a fear response to be more efficiently triggered upon repeated exposure to anxiety-provoking situation

Answer 26

amygdala “remembers” associated stimuli by increasing efficiency of glutamate neurotransmission in response to it

Question 27

what causes fear conditioning

Answer 27

when increased glutamate neurotransmission from the amygdala is not countered with input from the VMPFC to suppress the fear response, fear conditioning results

Question 28

what is fear extinction

Answer 28

progressive reduction of fear response when stimuli is repeatedly presented without adverse consequences

Question 29

how does fear extinction work

Answer 29

the VMPFC activates the amygdala over and over without fear being triggered then the hippocampus begins to remember the new context of the feared stimulus having no adverse consequences

Question 30

how does fear extinction overrule fear conditioning

Answer 30

when the new circuit has stronger synaptic connections and long-term potentiation it is able to produce inhibitory GABAerbic drive that overcomes excitatory glutamatergic drive

Question 31

what is reconsolidation

Answer 31

a memory becomes labile while being re-experienced and becomes malleable so that it can be modified

Question 32

classifications of drugs used to treat GAD

Answer 32

SSRI
SNRI
benzodiazepines
buspirone
ligands (pregabalin, gabapentin)

Question 33

off label txs for GAD

Answer 33

mirtazapine
trazadone
vilazodone
TCAs
sedating antihistamines (Vistaril)

Question 34

medication categories for treatment of panic disorder

Answer 34

SSRI
SNRI
benzodiazepines
ligands (pregabalin, gabapentin)

Question 35

off label treatments for panic attacks

Answer 35

mirtazapine
trazadone

Question 36

medication categories of treatment options for social anxiety disorder

Answer 36

SSRI
SNRI
ligands

Question 37

what is PTSD treatment often aimed at

Answer 37

comorbidities (depression, insomnia, substance abuse)