Anxiety Flashcards
what system mediates anxiety ? why does it occur ?
Limbic system - HPA axis
stress response enables to escape from potentially dangerous situations
what makes up the limbic system ?
Hippocampal formation
septal area
Amygdala
Prefrontal cortex (not a part but plays a role ) cingulate gyrus
where is hippocampus and what does it do ?
Medial surface of temporal lobe - floor of the horn of the lateral ventricle
Memory and expressions of emotion (Papez circuit) - inputs from cortex and projects to hypo/thalamus
where is the amygdala ? what does it do ?
Almond shape near tip of hippocampus in the roof of the lateral ventricle
Inputs from sensory , outputs to cortex and hypothalmus = drives related behaviours and processing of associated emotions.
what do prefrontal cortex and Cingulate gyrus do ?
Modulation of emotional responses from hypothalamus = “perception of emotion”
What is the endocrine element of the stress response ? what is the key hormone ?
limbic system is able to act on the hypothalamus to
stimulate the secretion of stress hormones Via the familiar hypothalamo-pituitary-adrenal axis
cortisol
what is the actions of cortisol ?
increase blood sugar
suppression of immune system
Inhibition of allergic and inflammatory process
what are the stages of the general adaptation syndrome?
outline each stage
1= The alarm reaction - NA released from sympathetic nerves and cortisol
- resistance - Chronic stress response, prolonged release of cortisol, NA wears off
- Exhaustion- prolonges stress = continued cortisol = muscle wastage , suppresion of immune system and hyperglycaemia
what is anxiety ?
a pathological response to stress (response greater than threat)
List some symptoms of anxiety
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
what are the classifications of anxiety disorders ?
Social phobia specific phobias Generalised anxiety disorders Panic disorders- Panic attacks OCD PTSD
what is the Pathophysiology of anxiety disorders ?
GABA levels appear to be low in some anxiety disorders
what is the model for treating anxiety ?
what drugs are used
Bio- benzos (short term), SSRIs, Pregabalin
Psychological - CBT
social - Support groups
what is the epidemiology of OCD?
Age of onset ?
sex ?
1 in 50 people
1/3 cases start between 10-15 yrs
Equal prevalence in males and females
what is an obession?
Thoughts that persist and dominate an individual’s thinking despite
their awareness that the thoughts are either entirely without purpose, or have persisted and dominated their thinking beyond the
point of relevance or usefulness
unpleasant and repugnant = anxiety
what is a compulsion ?
A motor act (or sometimes a thought) resulting from an obsession . Acting out a compulsion may relieve the anxiety provoked by its
associated obsession, but frequently carrying out the compulsion is also unpleasant
what is the diagnostic criteria for OCD?
Obsession +/- compulsion lasts 2 wks
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
what are some theories on the pathophysiology of OCD?
Basal ganglia re-entry circuits
reduced serotonin
Reduced activity in cortical areas
Autoimmune - PANDAS
explain what a basal ganglia re-entrant circuit is
cortex projects to BG , BG projects to Cortex via thalamus . this creates loop where
obsessional thoughts can re-enter the cortex having
entered the basal ganglia.
may be due to overactivity in direct pathway
What is treatment principles of OCD?
Biological • SSRIs +/- antipsychotics (Clomipramine) • Deep brain stimulation? Psychological • CBT and variety of other interventions Social • Family support • Groups etc
What is PANDAS? How is it caused ?
sudden onset of OCD after infection with group A strep
Antibodies cross react with neurones in basal ganglia-
treat with Antibiotics and OCD management
what are features of PTSD?
Can occur within six months following an exceptionally severe traumatic event
repetitive, intrusive recollection or re-enactment of the event in memories, daytime imagery, or dreams
conspicuous emotional detachment, numbing of feeling, and avoidance of stimuli that might arouse recollection of the trauma
what are theories on pathophysiology of PTSD?
Evidence of amygdala hyperactivity causing exaggerated
behavioural responses
• However, low levels of cortisol!
what are treatment principles for PTSD ?
Biological
SSRIs
Maybe short term benzodiazepines
Psychological
CBT
Eye movement desensitization reprocessing therapy
Social- Charities are particularly active, such as ‘Help for Heroes’
