Anxiety Disorders

Question 1

Locus Coeruleus

Answer 1

Brain stem, area of NE synthesis and releases to limbic System (amygdala), hypothalamus, frontal and parietal cortex.

Panic: after stressful events the neurons that release NE will bind to inhibitory receptors in own cell body to reduce excitability (feedback) but in panic this is dysfunctional and neurons in LC are not inhibited so they continue to fire alerting signals to limbic System

Question 2

Amygdala

Answer 2

After frightening events the amygdala encodes certain elements of experience.

Acquired fears are more resistant to extinction

Ex: amnesia patient “sometimes pins are hidden in people’s hands”

Question 3

ACC

Answer 3

Von economo (spindle neurons) which are important for humans

Connections with motor, premotor, and prefrontal cortex and insula.

Attention, cognitive control, consciousness, and conflict

Those with anxiety are more reactive

Question 4

GABA

Answer 4

Important for inhibition

Opens chloride ion channels, then chloride ions enter and create negative charges which leads to hyperpolarization of the neuron

Benzodiazepines open these channels

Question 5

Serotonin

Answer 5

Inhibitory serotonin receptors in LC

Serotonin receptors in hypothalamus

Serotonin inhibits the amygdala

Decreased serotonin in relation to anxiety

More serotonin leads to more inhibition if LC and less anxiety

Question 6

Mindfulness and brain networks

Answer 6

Default mode: mind wandering, automatic, rumination (past)

Central executive: paying attention, used in mindfulness (present)
(Both are anti correlated)

Salience: facilitates change from default to central executive. Active when behavioral change is needed