Anxiety Penultimate Lecture Flashcards
Five Classes of Anxiety Disorders to know for neuro Gp pop (no s ones)
- Generalised anxiety disorders occur in the absence of any precipitating stimulus.
- Phobia anxiety disorders are triggered by exposure to particular objects or situations.
- Panic disorders are rapid-onset attacks of extreme fear and severe stress symptoms (e.g. choking, heart palpitations).***
- Obsessive-compulsive disorders are characterised by frequently recurring, uncontrollable anxiety producing thoughts (obsessions) and impulses (compulsions). ***
- Posttraumatic stress disorder is an ongoing emotional reaction to an extreme psychological trauma.
What is anxiety?
▪ Anxiety is an affective state characterised by:
- cognitive expectations of a diffuse and certain danger.
- an internal physiological preparedness to deal with the threat (e.g. increased heart rate) and an external
physiological sign of anxiety (e.g. pale skin, trembling)
- an emotional sense of dread, fear, panic or worry.
- behaviours directed at escaping or avoiding the source of anxiety
▪ Anxiety is adaptive if it motivates effective behaviours, but if the behavioural component becomes maladaptive, it is referred to as an anxiety disorder.
Read PTSD in text
Done?
Panic Disorder characteristics/correlates
▪ People with panic disorder suffer from episodes of acute and unremitting terror characterised by recurring panic attacks.
Happens more often in women. Adolescents
▪ Symptoms of panic attacks are universal .
Physical symptoms of panic attacks include shortness of breath, perspiration, irregularities in heartbeat, dizziness and faintness.
▪
The victim of a panic attack thinks he/she is going to die.
▪ Between panic attacks, the person may/will experience anticipatory anxiety: the fear that another panic attack will strike.
Subtypes/comorbid?
➔ Agoraphobia (fear of open spaces) prevents the person venturing outside the house.
What Causes Physical Symptoms of Panic Attacks?
▪ Lactic acid (a by product of muscular activity) and breathing air with elevated levels of CO2, anarobic exercise.
- increase heart and rate of respiration
Yohimbine (an α2 adrenergic receptor antagonist) and
caffeine
- have direct stim pharmacological effects on the nervous system
- People with panic disorder have a family history of anxiety disorders.
Pharmacological Treatment: Benzodiazepines
For panic disorder
▪ Clinically used benzodiazepines such as diazepam (i.e. valium) are full agonists at the benzodiazepine receptor.
The benzodiazepine receptor forms part of the GABAA receptor complex.
▪too much puts you to sleep.
▪ Benzodiazepine agonists increase sensitivity of the GABA binding
site ➔ anxiolytic effect, reduce anxiety by
▪ Benzodiazepine antagonists occupy the receptor thereby reducing sensitivity of GABA binding site ➔ anxiogenic effect. Increase anx.
▪ Treatment of flumazenil (a benzodiazepine antagonists) produces panic in patients with panic disorder, not controls (Nutt et al., 1990).
Suggests Anx, caused by dismissed benzo emperors in certain ppl.
Benzopdiazepines are ? And this is an issue to ocnsider
Addictive
▪ Benziodiazepine is a psychoactive drug because it causes a change in perception, mood and consciousness.
▪ Long term use of benziodiazepine causes physical dependence.
Dose dependant too! I’d add
▪
Benzodiazepines are also used to
treat the panic caused by hallucinogen intoxication.
▪ Benzodiazepines can also be prescribed as sleep-inducing, muscle relaxants, and sedatives.
Pharmacological Treatment: Serotonin
▪ Selective Serotonin Reuptake Inhibitors (SSRI’s) are very effective in treating panic attacks.
In anxiety, SSRI efficacy is related to the
5-HT1A receptor!
Demonstrated by a mouse elevated plus maze. Cross open exposes or not arms.
Mice with 4 weeks treatment of SSRI’s are more likely to enter an elevated, open, brightly lit arm to retrieve food (i.e. less anxious).
- the drug has no effect on mice with targeted mutation against 5-HT1A receptor (Santarelli et al., 2003).
In mice, turning off the 5-HT1A receptor gene in the
hippocampus and cerebral cortex during embryological development leads to anxious behaviour during adulthood.
- If the gene is turned off during adulthood, there is no effect on anxious behaviour.
Presence of serotonin could have different effects at different times during an animals life.
Obsessive-compulsive Disorder (OCD)
▪ OCD patients suffer from obsessive distressing, intrusive thoughts which they are eager to remove or neutralise with compulsive acts or rituals.
▪ Obsessions:
- Disgust with bodily waste
- fear that something terrible might happen
- need for symmetry, order and exactness
- perverse sexual thoughts, images, impulses
▪ Compulsions:
- excessive, ritualised hand washing, showering, bathing
- ordering, arranging, counting, hoarding
- checking stoves, burners, locks, windows
- miscellaneous rituals (licking, spitting, special dress
patterns)
Possible aetiology of OCD
▪ Patients with OCD have tics and patients with Tourette’s syndrome show obsessions and compulsions. Perhaps same underlying genotype?
▪ OCD can occur after brain damage; symptoms are associated with damage/dysfunction of basal ganglia and prefrontal cortex.
▪ OCD is associated with increased activity in orbitofrontal cortex and caudate nucleus of the basal ganglia.
Group A β-hemolytic streptococcal infection can attack the tissue of the basal ganglia. Cause ocd
Cingulotomy as a treatment for OCD
▪ A cingulotomy is the surgical destruction of the cingulum bundle of fibres which connect limbic structures of the temporal lobe with the frontal lobe. Limits transmission presumably.
▪ Cingulotomy is considered the last resort in patients and used when conventional treatments fail to work. Used to be first.
▪ Adverse effects of surgery include problems in planning, behavioural inhibition and apathy.
Drug Therapy for OCD?
▪ Leonard et al (1989) compared the effects of chlomipramine (SSRI) with desipramine (SNRI).
▪ All patients received placebo for three weeks.
▪ For five weeks, half were treated with chlomipramine and the other half with desipramine (phase A).
▪ Treatments were then switched for another 5 weeks (phase B).
▪ Chlomipramine is more effective, overall the ssri
Serotonergic Activity Inhibits Compulsive Behaviours,
Control compulsions.
▪ Chlomipramine can successfully treat?
- Trichotillomania, compulsive hair pulling (and
sometimes eat them). - Onychophagia, compulsive nail biting
- Acral lick dermitius in dogs is a compulsive tendency to lick parts of their body which which eventually erodes away the skin.
Symptoms of Autistic Disorder (I) social
▪ Failure to develop normal social relationships
▪ Self-absorbed
▪ Avoid eye contact; do not look at others, or smile
▪ Don’t want to be held or touched.
▪ Abnormal language development; they may echo what is said to them and refer to themselves in second or third person. E.g. “you want some milk” means I want some milk.
▪ May interpret others speech literally. E.g. when asked “Can you pass the salt?” ➔ “Yes.”
