S11) Anxiety Disorders Flashcards
What is the limbic system?
- The limbic system is a set of brain structures located on both sides of the thalamus, immediately beneath the cerebrum
- It supports a variety of functions including emotion, behavior, motivation, long-term memory, and olfaction
Identify the components of the limbic system
- Hippocampal formation
- Septal area
- Amygdala
- ± Prefrontal cortex
- ± Cingulate gyrus
Briefly outline the functioning of the limbic system
Briefly outline the limbic-hypothalamo- pituitary-adrenal axis
What are the actions of cortisol?
- Increase of energy metabolite levels
- Suppression of immune system
- Inhibition of allergic and inflammatory processes
What are the three components of the general adaptation syndrome?
Which three process occur in the alarm reaction part of general adaptation syndrome?
- NA release from sympathetic nerves
- Adrenaline and NA release from adrenal medulla
- Cortisol release from adrenal cortex
What occurs in the resistance part of general adaption syndrome?
Resistance – action of cortisol is longer lasting than adrenaline, allows maintenance of response to stress
What occurs in the exhaustion part of general adaptation syndrome?
Exhaustion – prolonged stress causes continued cortisol secretion, leading to muscle wastage, suppression of immune system and hyperglycaemia
What is anxiety?
Anxiety is a feeling of worry, nervousness or unease about something with an uncertain outcome
What are the symptoms of anxiety?
- Palpitations
- Sweating
- Trembling
- Difficulty breathing
- Chest pain
Identify six different types of anxiety disorders
- Social phobia
- Specific phobias
- Generalised anxiety disorder
- Panic disorder
- Obsessive compulsive disorder (OCD)
- Post-traumatic stress disorder (PTSD)
In terms of the functional neuro-imaging, explain the effect of common anxiety disorders on the following parts of the brain:
- Amygdala
- Cingulate cortex
- Hippocampus
- (+) Increased function
- (-) Decreased function
- (-/+) Both increased and decreased function
- (?) Too little information
Explain the relationship between GABA levels and anxiety (and the treatment of such)
- GABA levels are decreased in cortex in patients with panic disorder
- Benzodiazepines increase GABA transmission so reduce anxiety
Explain the relationship between serotonin levels and anxiety (and the treatment of such)
- Increased levels of serotonin (due to SSRIs) may stimulate serotonin receptors in hippocampus
- Leads to neuroprotection, neurogenesis and reduction of anxiety