Session 11 L2: Anxiety Disorders Flashcards Preview

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Flashcards in Session 11 L2: Anxiety Disorders Deck (30)
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1
Q

What are the components of the limbic system?

A
  • Hippocampal formation
  • Septal area
  • Amygdala
  • Prefrontal Cortex
  • Cingulate Gyrus
2
Q

What are the components of the stress response?

A
  • Limbic system

- Limbic-hypothalamo-pituitary-adrenal axis

3
Q

What is the hippocampal formation?

A
  • Curved piece of cortex folded into medial surface of temporal lobe
  • Occupies floor of temporal horn of lateral ventricle
  • 3 parts: Subiculum, Hippocampus Proper, Dentate Gyrus
  • Involved in memory and expression of emotion
4
Q

What is the amygdala?

A
  • Collection of nuclei buring in the roof of the lateral ventricle
  • Inputs of sensory information, brainstem, thalamus and cortex
  • Outputs to cortex, brainstem and hypothalamus
  • Drive related behaviours and processing of associated emotions
5
Q

What is the action of prefrontal cortex?

A

Modulatory effect on processes associated with the hypothalamus

6
Q

What is the action of the cingulate gyrus?

A

Modulatory effect on processes associated with the hypothalamus

7
Q

What is the action of the limbic-hypothalamo-pituitary-Adrenal axis?

A

Actions of Cortisol

  • Increase of energy metabolite levels
  • Suppression of immune system
  • Inhibition of allergic and inflammatory processes
8
Q

What is the action of the sympathetic nervous system during stress?

A
  • Increased heart rate and force of contraction

- Dilated bronchi

9
Q

What are the system of general adaptation syndrome?

A
  • Alarm reaction
  • Resistance
  • Exhaustion
10
Q

Describe the alarm reaction stage of the general adaptation syndrome.

A
  • Noradrenaline release form sympathetic nerve
  • Adrenaline and noradrenaline release from adrenal medulla
  • Cortisol release from adrenal cortex
11
Q

Describe the resistance stage of the general adaptation syndrome.

A

-Action of cortisol is longer lasting than adrenaline, allows maintenance of response to stress

12
Q

Describe the exhaustion stage of the general adaptation syndrome.

A

-Prolonged stress causes continued cortisol secretion, leading to muscle wastage, suppression of immune system and hyperglycaemia

13
Q

What is anxiety?

A

Feeling of worry, nervousness or unease about something with an uncertain outcome.

14
Q

What are the symptoms of anxiety?

A
  • Palpitations
  • Sweating
  • Trembling or shaking
  • Dry mouth
  • Difficulty breathing
  • Chest pain or discomfort
  • Nausea or abdominal distress (e.g. butterflies in stomach)
  • Feeling dizzy, unsteady, faint or light-headed
15
Q

What are types of anxiety disorders?

A
  • Social phobia
  • Specific Phobias
  • Generalised anxiety disorder
  • Panic disorder
  • Obsessive Compulsive Disorder
  • Panic disorder
16
Q

What is the GABA theory for anxiety?

A
  • GABA is the main inhibitory neurotransmitter
  • GABA levels are decreased in cortex in patients with panic disorder
  • Benzodiazepines increase GABA transmission so reduce anxiety
17
Q

What is the serotonin theory for anxiety?

A
  • Increased levels of serotonin may stimulate serotonin receptors in hippocampus
  • Leads to neuroprotection, neurogenesis and reduction of anxiety
18
Q

How is anxiety treated?

A
  • Mainstay of treatment is SSRIs
  • Cognitive Behavioural therapy
  • Can use pregabalin – a GABA analogue
19
Q

Why aren’t benzodiazepines used long term for anxiety disorders?

A

-Don’t use benzodiazepines for too long due to increased tolerance to them and addictive. Also they are dangerous in overdose

20
Q

What are the features obsessive compulsive disorder?

A
  • 1 in every 50 suffers from OCD at some point in their lives
  • Usually being in adolescence or early adulthood. 33% are 10-15. 75% started by age 30. Lifetime prevalence of around 2%.
  • Same ratio for men and women but childhood OCD more common in boys
21
Q

What are obsessions?

A

-A thought that persists and dominates an individual’s thinking despite their awareness that the thought is either without purpose or has persisted and dominated their thinking beyond the point of relevance or usefulness.

22
Q

What are compulsions?

A

-Obsessional motor acts. May result from an obsessional impulse that leads directly to the action or they may be mediated by an obsessional mental image or fear. Can lead to patients wasting a lot of time. Can also have mental compulsions e.g. repeating phrases

23
Q

What is the pathophysiology of OCD?

A
  • Re-entry circuits in the basal ganglia
  • Reduced serotonin
  • Reduced activity in dorsolateral prefrontal cortex
  • Reduced activity in orbitofrontal cortex
  • Increased activity in the cingulate gyrus
  • PANDAS
24
Q

Describe re-entry circuits in the basal ganglia.

A
  • Input from cortical and subcortical areas
  • Processing occurs in the caudate nucleus and putamen. This allows integration of information. Basal ganglia encode for the decision to move, the direction and amplitude of movement and motor expression of emotion
  • Output via inhibitor projections from globus pallidus and thalamus to cortex to bring about movement
  • Re-entry circuits exist between the output and processing
25
Q

Describe PANDAS

A
  • Sudden onset of OCD symptoms or tics after infection with Group-A beta-haemolytic strep
  • Usually dramatic onset of psychiatric or behavioural problems
  • Antibodies ‘cross-react’ with neurons in basal ganglia, causing symptoms
26
Q

What are the diagnostic criteria for OCD?

A
  • Obsessions/Compulsions/both present on most days for a period of at least 2 weeks
  • Obsessions and compulsions share all of the following features (Originate in the mind of the patient, Repetitive and unpleasant, Acknowledged as excessive or unreasonable, Patient tried to resist, but at least one obsession/compulsion is unsuccessfully resisted)
  • Carrying out the obsessive thought or act is not in itself pleasurable
  • Obsessions/Compulsions must cause distress or interfere with the patient’s social or individual functioning
27
Q

What is the treatment of OCD?

A
  • Cognitive behavioural therapy
  • Exposure response prevention
  • High Dose SSRIs (need higher dose and longer treatment course than in depression)
  • Augmentation with antipsychotics
  • Clomipramine (unpleasant side effects)
  • Deep brain stimulation
28
Q

What is diagnostic criteria of post traumatic stress disorder?

A
  • Within 6 months of traumatic event of exceptional severity
  • Evidence of trauma
  • Repetitive, intrusive recollection or re-enactment of the event in memories, day time imagery, or dreams
  • Conspicuous emotional detachment, numbing of feeling and avoidance of stimuli that might arouse recollection of the trauma
29
Q

What is the pathophysiology of PTSD?

A
  • Hyperactivity of amygdala, causing exaggerated response to perceived threat
  • Cortisol inhibits traumatic memory retrieval and control sympathetic response
  • In PTSD, Lower than normal levels of cortisol
30
Q

What is the treatment for PTSD?

A
  • Medical treatment (same as other anxiety disorder)
  • Cognitive based therapy
  • Eye movement desensitisation
  • Reprocessing (EDMR)