Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Module 202 Theme 3 > Anxiety disorders: Neurobiology, neurochemistry and treatment > Flashcards

Anxiety disorders: Neurobiology, neurochemistry and treatment Flashcards

1
Q

Which part of the brain plays a role in fear?

A

Amygdala

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does activation of the amygdala cause?

A

Tachycardia, paleness, pupil dilation, blood pressure elevation
Behavioural and EEG arousal increased vigilance
Corticosteroid response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does the amygdala excite?

A

Locus coeruleus

Hypothalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe the acute stress response

A
  • Avoidance behaviour
  • Increased vigilance and arousal
  • Activation of the sympathetic division of the ANS
  • Release of cortisol from the adrenal glands
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe the HPA axis

A 
Hypothalamus releases CRH
Pituitary releases ACTH 
Adrenal cortex releases cortisol
	(stress hormone)
(CRH: corticotropin releasing hormone
ACTH: adrenocorticotropic hormone)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does the Locus Coeruleus release?

A

Norepinephrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the regulation of HPA axis?

A

Push and pull regulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What happens during Chronic activation of glucocorticoid receptors in hippocampus?

A
  • increased Ca2+ entry into neurons
    - too much Ca2+ - excitotoxic - cells dieHippocampus can’t feedback to limit cortisol production
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What do anxiety disorders result from?

A
  • diminished activity of hippocampus
  • loss of feedback to the amygdala
  • inappropriate fear responding

(evidence - hippocampal volume in PTSD patients reduced)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the noradrenergic system involved in?

A

Arousal and attention

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the serotonergic system involved in?

A

Mood and emotion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where do the noradrenergic and serotonergic systems project to?

A

Throughout the forebrain to both cortical and limbic areas as well as connections to each other
They are also thought to balance each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What can dysregulation of limbic systems or connections cause?

A

Inappropriate fear and anxiety responses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

List some anxiety disorders

A 
Post traumatic stress disorder
Panic disorder
Generalized anxiety disorder
Phobia
Obsessive compulsive disorder
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is PTSD?

A

persistent psychological stress following exposure to extreme stress, e.g. war, physical assault

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is panic disorder?

A

rapid-onset attack of extreme fear and severe stress
Characterized by unrealistic, unfounded fear and anxiety; acute and unremitting terror for variable lengths of time (sec to hours).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is Generalized Anxiety Disorder (GAD):

A

stress and anxiety in the absence of obvious precipitating stimulus

18
Q

What are phobias?

A

similar to GAD, but triggered by particular objects (e.g. spiders, birds) or situations (e.g. crowds, darkness)

19
Q

What is Obsessive Compulsive Disorder (OCD):

A

frequently recurring, uncontrollable, anxiety-producing thoughts (obsessions) and impulses (compulsions). Responding to them, e.g. repeated, compulsive hand washing, dissipates associated anxiety.

20
Q

Describe the features of panic disorder

A

Anxiety is normally useful/adaptive
Universal basic symptoms, e.g. shortness of breath, “impending death”, irregular heartbeat, clammy sweat, dizziness, faintness
Onset in young adulthood
More likely to appear in women
Treatable
Anticipatory anxiety (fear that another panic attack will strike) often leads to development of agoraphobia
Often accompanied by other serious problems: depression, alcoholism or drug abuse

21
Q

Describe the treatment of panic disorder

A

Benzodiazepines, partial agonists of the GABA(A) receptor, anxiolytic [sedation & sleep induction, reduced muscle tone & coordination, anticonvulsant effects, anterograde amnesia]

Serotonin, SSRIs (serotonin selective reuptake inhibitors)
Cognitive Behavioural Therapy (CBT)

22
Q

In what anxiety disorders do benzodiazepines work well?

A 
Generalized Anxiety Disorder (GAD)
Panic Disorder (PD)
23
Q

In what anxiety disorders do benzodiazepines not work as well?

A

Obsessive Compulsive Disorder (OCD)

Post Traumatic Stress Disorder (PTSD)

24
Q

In what anxiety disorders do SSRIs work well in?

A

OCD
PTSD
Panic Disorder
GAD

25
Q

Which drug works in GAD?

A

GAD

26
Q

Name some drugs which increase GABA activity to reduce anxiety

A

Partial agonist Alcohol

Indirect agonists Barbiturates
Benzodiazepines

27
Q

Which drugs which decrease GABA activity to increase anxiety?

A

Benzodiazepine antagonist Flumazenil

These drugs all act at the GABA(A) ionotropic receptor

28
Q

What happens to the benzodiazepine binding sites in the brain of someone with panic disorder?

A

Fewer binding sites

29
Q

Which area of the brain shows increased activity during periods of anxiety?

A

the frontal cortex normally shows increased activity during periods of anxiety

30
Q

Describe anxiety and depression

A

often comorbid (e.g.~85% depressed show symptoms of GAD)
both treatable with SSRIs
both weeks before therapeutic actions are visible

Therapeutic effect is not simply boosting the synaptic levels of serotonin - otherwise changes would be seen on initiation of treatment

Instead as a result of adaptive changes by the nervous system to the chronically elevated levels of serotonin

31
Q

Describe neuroplasticity downstream of antidepressants

A

Intracellular cascades downstream of 5-HT receptor activation can lead to changes in neuronal plasticity and morphology

Remember: neurogenesis in adult hippocampus

Reversal of stress induced changes may restore normal function to a brain

Hypothesis may hold for depression and anxiety

32
Q

Where do the opposing functions of various brain areas in panic disorder act?

A

Opposing functions in various brain areas
hippocampus
amygdala
hypothalamus

33
Q

Describe Obsessive compulsive disorders

A

Frequently recurring, uncontrollable, anxiety-producing thoughts (obsessions) and impulses (compulsions). Responding to them, e.g. repeated, compulsive hand washing, dissipates associated anxiety.

OCD patients recognize their thoughts and behaviours are senseless.

1-2% incidence

Categories of compulsions: counting, checking, cleaning, avoidance (exaggeration of natural human tendencies)
e.g. trichotillomania, onychophagia

Greater concordance with monozygotic than dizygotic twins
Common underlying genotype for Tourette’s and OCD
Can be environmental as well - Streptococcal infection
Experience also plays a role, e.g. stressful life events

A disorder of the basal ganglia?
Repeated behaviours - follow rituals
Associated with Tourette’s syndrome – hereditary chronic motor tic disorder (muscular and vocal tics) that has its locus in the basal ganglia
Imbalance between indirect and direct pathways through basal ganglia

34
Q

What gives rise to the direct and indirect pathways?

A

Two types of dopamine receptors (D1 and D2) are located on different sets of output neurons in the striatum that give rise to the direct and indirect pathways.

35
Q

Describe how the direct and indirect pathway link to OCD

A

Direct pathway controlling previously learned behavioural sequences so they become automatic and can be rapidly executed

Indirect pathway involved in suppressing these automatic behaviours allowing the person to switch to other more adaptive behaviours (behavioural flexibility).

Overactivity of direct pathway may lead to these compulsive behaviours without being able to switch them off

36
Q

What is the best drug treatment of OCD?

A

SSRIs

e.g. fluoxetine but also clomipramine (TCA)

37
Q

Describe how caudate hyperactivity leads to OCD

A 
The caudate sends GABAergic
inhibitory projections to the GP,
which sends inhibitory projections
to the thalamus, which then 
projects to the OFC.

It’s possible that OCD involves a
disinhibition which leads to activity
reverberating in this circuit.

CBT and SSRIs lead to a similar
biological change .

38
Q

Describe the pros and cons of using benzodiazepines in the treatment of anxiety disorders

A

good immediate effects, but patients can develop tolerance and there is potential for abuse, and anxiety during withdrawal

39
Q

Describe the pros and cons of using SSRIs in the treatment of anxiety disorders

A

are effective, but have a delayed onset. Initially can be anxiogenic.

40
Q

What is the best strategy in treatment of anxiety disorders?

A

Combining benzodiazepines and SSRIs initially and then tapering off the BDZs as the SSRIs take effect

Module 202 Theme 3 (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions