11.2 anxiety Disorders Flashcards
What is anxiety?
A feeling of worry, nervousness, or unease about something with an uncertain outcome. Future focused, linked to threat.
What are 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 is the physiological role of the stress response?
Previously used to enable us to escape from potentially dangerous situations
What are the 2 main targets of the lambic system when producing the stress response?
Endocrine targets = hypothalamus
Neural targets = hippocampus, amygdala, prefrontal cortex,
Describe the role of the hippocampus in the stress response?
Relates stress response with a perceived threat/experience. Receives inputs from many parts of the cortex and processes their emotional content. Projects to the thalamus (and hence back to the cortex – the Papez circuit) and also to the hypothalamus (causing autonomic features of emotional responses). This will lead to sympathetic nervous system activation, as well as release of adrenaline from the adrenal medulla
Role in memory – Papez circuit may be involved in memory consolidation
What is the acute stress response?
Symptoms that develop after a particularly stressful event.
Caused by the release of adrenalin from the sympathetic nervous system.
Where is the amygdala located?
Almond shaped structure sittin near the tip of the hippocampus.
What is the role of the amygdala?
Receives inputs from the sensory system and is involved in behavioural and autonomic emotional responses. Major outputs to the cortex and hypothalamus
What role does the prefrontal cortex have in the stress response?
Modulation of emotional responses ( consciously suppressing features of anxiety)
Perception of emotion
What are the endocrine elements of anxiety?
The limbic system acts on the hypothalamus to activate the hypothalam-pituitary-adrenal axis. This increases the amount of cortisol released by the adrenal medulla.
Also activates the hypothalamospinal tract, increasing the stimulation of the autonomic preganglionic neurones. (Sympathetic activation)
What are the 3 stages of the general adaptation syndrome?
Stage 1: The alarm reaction. Release of adrenaline and cortisol as well as sympathetic activation
Stage 2: Resistance (effect of adrenaline starts to wear off). Chronic stress response, prolonged release of cortisol
Stage 3: Exhaustion (when you cannot escape an ongoing stressor). Chronic side effects of prolonged cortisol secretion start to occur
What are the 6 classifications of anxiety response?
Social phobia Specific phobias Generalised anxiety disorder Panic disorder obsessive compulsive disorder
What is the pathophysiology of anxiety disorders?
Unclear
Equivocal findings in studies of brain activation patterns
GABA levels appear to be low in some anxiety disorders (maybe
explaining action of benzodiazepines) Increasing serotonin levels can help treat anxiety disorders
(mechanism unclear, but hippocampus may be involved)
What are the treatments for generalised anxiety disorders?
Biological • Short term benzodiazepines • SSRIs Psychological • Cognitive behavioural therapy - Getting patients to reflect on their feelings/thoughts/behaviours Social • Support groups, charities etc
People with OCD exhibit obsessive thoughts. What dose this mean?
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, often causing anxiety
People with OCD often have to carry out a compulsion to relieve the anxiety brought on by an obsession. What is a compulsion?
An often unpleasant 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
How long must a patient be suffering from obsessions and /or compulsions to be qualifying as having OCD?
2 weeks
What common features do obsessions and compulsions have?
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 proposed hypothesis for OCD?
Basal ganglia re-entrant circuits Reduced serotonin levels Altered activity in a range of cortical areas Autoimmune aetiologies PANDAS
What are the diagnostic criteria for a patient suffering with OCD
Obsessions/compulsions both present on most days for a period of at least 2 weeks
Acknowledge as excessive or unreasonable
Repetitive and unpleasant
Obsessions/compulsions must causes distress or interfere with the patient’s social or individual functioning
Describe the mechanism of basal ganglia re entry hypothesis for the causation of OCD?
After the globus pallidus and the thalamus communicate to the cortex to stimulate a desired output, instead of completing the cycle, instead there is re-entry into the circuit in the processing stage by the caudate nucleus and the putamen (striatum). This progresses yet again to the output phase by the globus pallidus and thalamus. This cycle can occur many times before the action is complete
What is PANDAS?
Paediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcal Infection
- Sudden onset of OCD symptoms or tics after infection with Group-A beta-haemolytic strep. Usually 3-12 years. Usually dramatic onset of psychiatric or behavioural problems. Antibodies ‘cross-react’ with neurons in basal ganglia, causing
symptoms
How is paediatric autoimmune neuropsychiatric disorder associated with streptococcal infection treated?
With antibiotics and usual management of OCD
What is the normal treatment of OCD?
Cognitive behavioural therapy CBT
Exposure response prevention
High dose SSRIs (sertraline) - augmentation with antipsychotics (clomipramine)
Deep brain stimulation of substantia nigra, interna globus pallidus.
What is PTSD?
Post traumatic stress disorder
Occurs within 6 months of a traumatic event of exceptional severity.
Repetitive 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 is the pathophysiology of PTSD?
Hyperactivity of amygdala, causing exaggerated response to perceived threat
Cortisol inhibits traumatic memory retrieval and controls sympathetic response. In PTSD, lower than normal levels of cortisol
What is the treatment for PTSD?
CBT
Eye movement desensitisation and reprocessing
