L18 - Anxiety

Question 1

Anxiety

Answer 1

Feeling of worry or unease about something with an uncertain outcome

Question 2

Symptoms of anxiety

Answer 2

Palpitations
Sweating 
Trembling 
Dry mouth 
Difficulty breathing 
Chest pain and discomfort 
Nausea or abdominal distress

Question 3

Stress response

Answer 3

Limbic hypothalamo- pituitary adrenal axis

Cortex stimulates limbic structures
Limbic structures stimulate hypothalamus to release CRH - corticotropin releasing hormone
Stimulates pituitary to release ACTH - adrenocorticotropic hormone
Stimulates adrenal cortex to release cortisol

Question 4

Limbic system

Answer 4

Hippocampal formation:

• Hippocampus
• Dentate gyrus
• Aspects of the parahippocampal gyrus

Septal area
Amygdala

+/-
prefrontal cortex
Cingulate gyrus

Question 5

Hippocampus

Answer 5

Occupies floor of temporal horn of lateral ventricle

Three parts:

• subiculum
• hippocampus proper
• dentate gyrus

Involved in memory and expression of emotion

Question 6

Amygdala

Answer 6

• in the roof of lateral ventricle
• collection of nuclei
• controls drive related emotions and processing of associated of emotions
• can induce fear

- inputs of:
> sensory information 
> brainstem 
> thalamus 
> cortex 

Outputs:
> cortex
> brainstem
> hypothalamus

Question 7

Modulation of hypothalamus

Answer 7

Prefrontal cortex

Anterior cingulate gyrus

Question 8

Hypothalamus

Answer 8

Quickly activates sympathetic nervous system

Gradually activates adrenal cortical system by releasing CRH

Question 9

HPA axis effects

Answer 9

Involuntary
Increase of energy metabolites
Suppression of immune system
Inhibition of allergic and inflammatory processes

Question 10

General adaptation syndrome

Answer 10

1. Alarm reaction
   - NA release from sympathetic nerves
   - NA and adrenaline released from adrenal medulla
   - cortisol released from the adrenal cortex
2. Resistance
   - cortisol is longer lasting - maintenance of stress response
3. Exhaustion
   - prolonged stress - prolonged cortisol release
   - muscle wastage
   - suppression of the immune system
   - hyperglycaemia

Question 11

Anxiety disorders

Answer 11

Social phobia 
Specific phobias 
Generalised anxiety disorder 
Panic disorder 
OCD
PTSD 

• response is greater than the presenting threat

Question 12

GABA in panic disorder

Answer 12

GABA - inhibitory neurotransmitter

Decreased in panic disorders

Question 13

Benzodiazepines

Answer 13

Increase GABA transmission so reduce anxiety
Rapid

[alcohol can also do this]

Question 14

Selective serotonin reuptake inhibitors

Answer 14

Stimulate serotonin receptors in the hippocampus
Prevent reuptake of serotonin therefore more available
Neuroprotection
Neurogenesis
Reduction of anxiety

Question 15

Treatment of anxiety disorders

Answer 15

SSRIs
CBT
Pregabalin - GABA analogue

DON’T USE BENZODIAZEPINES LONG TERM

Question 16

Why aren’t benzodiazepines used long term

Answer 16

Benzodiazepine withdrawal symptoms
Become tolerant
Instant craving

Question 17

CBT

Answer 17

Situation
Thoughts 
Emotions 
Behaviour 
Physical reactions

Question 18

Obsessions

Answer 18

Thoughts that persist and dominate 
Awareness that thought has no purpose or not useful 
Repetitive and unpleasant 
Patient tries to resist 
Causes great anxiety and guilt

Question 19

Compulsions

Answer 19

Obsessional motor acts

Due to obsessional impulse or obsessional mental image or fear

Question 20

Diagnostic criteria of OCD

Answer 20

Obsessions or compulsions on most days for at least 2 weeks

Question 21

Epidemiology of OCD

Answer 21

Adolescence or early adulthood
Prevalence - 2%
Childhood OCD more common in boys
Overall male to female 1:1

Question 22

Tourette’s

Answer 22

Tics
ADHD
OCD
Behavioural problems

Question 23

OCD re entry circuit

Answer 23

Loop between output and processing

Question 24

PANDAS

Answer 24

Paediatric autoimmune neuropsychiatric disorder associated with streptococcal infection

• 3-12 yrs old
• sudden onset OCD symptoms or tics after infection of group A beta haemolytic strep
• antibodies cross react with neurones in basal ganglia
• respond to treatment with antibiotics and usual OCD management

Question 25

Treatment of OCD

Answer 25

CBT
Exposure response prevention - prevent the compulsion in the presence of the thought

High dose SSRI with longer treatment
Antipsychotics - clomipramine (TCA)

Question 26

PTSD

Answer 26

Within 6 months of a traumatic event of exceptional severity
Repetitive, intrusive recollection or re-enactment of the event in memories
Emotional detachment
Numbing feeling
Avoidance of stimuli

Question 27

Pathophysiology of PTSD

Answer 27

Hyperactivity of the amygdala

Exaggerated response to perceived threat

Question 28

Treatment of PTSD

Answer 28

Cortisol (conflicting evidence)

• inhibits traumatic memory retrieval
• controls sympathetic response

Medical treatment - SSRI
CBT
Eye movement desensitisation and reprocessing (EMDR)