Anxiety Flashcards
What is anxiety?
A feeling of worry, nervousness or unease about something with an uncertain outcome.
What are the symptoms of anxiety?
Palpitaions Sweating Trembling or Shaking Dry mouth Difficulty breathing Chest pain or discomfort Nausea or abdominal distress (butterflies in your tummy) Feeling dizzy, unsteady, faint or light-headed
What are the two parts of the stress response?
Limbic system
Limbic-hypothalamo-pituitary-adrenal axis
What it in the lymbic system
A hippocampal formation (hippocampus, dentate gyrus, parts of the parahippocampal gyrus)
Septal area
Amygdala
+/-
prefrontal cortex
Cingulate gyrus
What is the hippocampus?
A curved piece of cortex.
Folded into medial surface of temporal lobe.
Occupies floor of temporal horn of lateral ventricle
Three parts:
Subiculum, Hippocampus proper, dentate gyrus
It is involved in memory and expression of emotion
What is the amygdala?
It is buried in the roof of the lateral ventricle
Collection of nuclei
Inputs sensory information, brainstem, thalamus, cortex
Outputs to cortex, rainstem and hypothalamus
Drives related behaviours and processing of associated emotions.
What are the parts involved in anxiety
Hippocampus
Amygdala
Prefrontal cortex
Anterior cingulate gyrus
What odes the sympathetic nervous system do?
Increased heart rare and force of contraction
Dilated bronchi
What does cortisol do?
Increase of energy metabolite leaves
Suppression of immune system
Inhibition of allergic and inflammatory processes
What is general adaptation syndrome?
- Alarm reaction
NA released form sympathetic nerves.
Adrenaline and NA released from adrenal medulla.
Cortisol released from adrenal cortex - Resistance
Action of cortisol is longer lasting than adrenaline, allows maintenance of response to stress - Exhaustion
Prolonged stress causes continued cortisol secretion, leading to muscle wastage, suppression of immune system and hyperglycaemia
When is stress a problem?
When above optimum - so you get to exhaustion, anxiety/panic/anger then a breakdown
What are some anxiety disorders?
Social phobia Specific phobias Generalised anxiety disorder Panic disorder OCD PTSD
Anxiety disorders are then the response outweighs the threat
How does GABA change in panic disorder?
GABA levels are decrease in the cortex in patients with panic disorder.
Benzodiazepines increase GABA transmission so reduce anxiety.
But, addictive and can build up tolerance so not used for long periods of time.
How does serotonin help?
Increased levels of serotonin (due to SSRIs) may stimulate serotonin receptors in hippocampus.
Leads to neuroprotection, neurogenesis and reduction of anxiety
How can you treat anxiety disorders?
SSRIs
CBT
Pregabalin
Benzodiazepines but not long term
What is CBT?
Cognitive behavioural therapy
Situation Thoughts Emotions Behaviour Physical Reactions
Why do we are about OCD?
1 in 50 people suffer from OCD at some point in their lives.
That’s 1milllion people in the UK.
E.g. Charles Darwin, Florence Nightingale, David Beckham
What are obsessions in OCD?
A though that persists and dominates an individual’s thinking despite their awareness that the thought is eithe entirely without purpose, or has persisted and dominated their thinking beyond the point of relevance or usefulness.
Often causes grea anxiety and guilt.
Particularly repugnant to individual.
Reflex changes in society.
Obsessions are unpleasant
For example:
I might harm my baby
I might be a paedophile
God does not exist
What are compulsions?
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.
E.g ‘I need to turn the light switch on and off them times or my family will die’
Can lead to patients wasting a lot of time!
Can also have mental compulsions e.g. repeating phrases
What is the diagnostic criteria for OCD?
Obsessions / compulsions / both present on most days for a period of at least 2 weeks.
Obsessions and compulsions share all the following features:
Originate in the mind of the patient
Repetitive and unpleasant
Acknowledged as excessive or unreasonable
Patient tries 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 patients social or individual functioning.
Describe the epidemiology of OCD?
Usually begin in adolescence or early adulthood.
33% start between 10-15yrs old
75% started by age of 30
Lifetime prevalence around 2%
M:F 1:1 but childhood OCD is more common in boys
What are the theory of pathophysiology of OCD?
Nobody really knows! Suggested theories: Re-entry circuit in basal ganglia Reduced serotonin Reduced activity in dorsolateral prefrontal cortex Reduced activity in orbitofrontal cortex Increased activity in cingulate cortex PANDAS
Explain the basal ganglia
Input: From cortical and subcortical areas
Processing: Caudate nuclear and putamen (Striatum)
Allows integration of information.
Basal ganglia encode for the decision to move, the direction and amplitude of movement and motor expression of emotions.
Output: Inhibtior projections from globes palliduc and substantia nigra to thalamus via GABA-ergic neurones.
How does basal ganglia change in OCD?
Re-entry
So, rather than one output being enough, it will go back to processing and output again because the brain thinks it has not been done well enough.
