11. Anxiety Disorders Flashcards
what is the purpose of the stress response?
enables us to escape from potentially dangerous situations
which system is primarily involved in the stress response?
limbic system
what is the purpose of the hippocampus?
receives input from many parts of the cortex and processes emotional context, projects to thalamus (and thus back to cortex) and to the hypothalamus (hypothalmospinal tract to autonomic preganglionic neurones)…this leads to sympathetic activation and adrenaline release from the medulla
also role in memory
what is the purpose of the amygdala?
receives many inputs from the sensory system, and major outputs to cortex and hypothalamus
role in behavioral and autonomic emotional responses
what is the purpose of the prefrontal cortex?
modulation of emotional responses and perception of emotion
how are the stress hormones secreted?
limbic system acts on hypothalamus via the familial hypothalamo-pituitary adrenal axis. cortisol is released from adrenal cortex
what stages does the body go through during prolonged exposure to stressors?
STAGE 1: ALARM REACTION - release of adrenaline and cortisol and sympathetic activation
STAGE 2: RESISTANCE - effect of adrenaline starts to wear off, chronic stress response and prolonged release of cortisol
STAGE 3: EXHAUSTION - chronic side effects of prolonged cortisol secretion start to occur
when does the stress response become pathological?
when you cannot escape the stressor or when the stress response is too strong
define anxiety
pathological stress response
what are some common symptoms of anxiety?
palpitations, sweating, trembling, dry mouth, difficulty breathing, chest pain, nausea, abdominal distress, dizzy, unsteady, faint
how are anxiety disorders classified?
social phobia
specific phobias - height
generalised anxiety disorder - persistent anxiety about various thing
panic disorder - recurrent, unexpected panic attacks
OCD
PTSD
what neurotransmitter level seems to be low in anxiety disorders?
GABA
how can anxiety disorders be treated?
increase the serotonin levels - so SSRIs or short term benzodiazepines
also cognitive behavioural therapy as well as support groups
how common is OCD?
1 in 50 (usually by 30)
what is OCD characterized by?
obsessions and compulsions that originate in the mind of the patient, are repetitive and unpleasant, are acknowleged they are unreasonable, patient tried to resist but unsuccesfully
define obsessions
thoughts that persist and dominate an individual’s thinking despite their awareness that the thoughts are entirely without purpose or have persisted and dominated their thinking beyond point of relevance. can be unpleasant and cause anxiety
define compulsions
a motor act or can be a thought resulting from an obsession, and by doing so relieves the persons anxiety but usually unpleasant
what are the hypotheses for the pathophysiology of OCD?
the cortex projects to basal ganglia which then project back to the cortex so the obsessional thoughts can re enter the cortex having entered the basal ganglia…due to over activity in the direct pathway
or
low serotonin
or
alterted activity in corticla areas
or
autoimmune (cross reactivity with basal ganglia and strep antigens)
how is OCD treated?
SSRI’s, deep brain stimulation, CBT, family support
what is the common presentation of PTSD?
following severely traumatic event
causes repetitive, intrusive recollection or re enactment of the event in memories, daytime imagery or dreams
emotional detachment, numbing of feelings, avoidance fo stimuli that may trigger
what are the hypotheses of the pathophysiology of PTSD?
amygdala hyperactivity
low levels of cortisol
how is PTSD treated?
SSRIs short term benzodiazepines CBT eye movement desensitization reprocessing therapy charities such as help for heroes
