Lecture 14- Sz and affective disorders Flashcards
What are the key concepts of Sz?
-Affects 1:300 people so approximately 24million people.
-Onset commonly during adolescence -Considered a type of psychosis (loss of contact with reality)
What are some examples of positive symptoms?
Hallucinations
Thought disorders
Delusions eg grandeur
What are some examples of negative symptoms?
Poverty of speech
Anhedonia (lack of interest)
Social withdrawal
Flat emotional repsonses
What are some examples of cognitive symptoms?
Low psychomotor speed
Poor problem solving
Poor abstract thinking
What are the neurology symptoms?
Ventricular enlargement is one of the earliest and most consistent findings in schizophrenia. The ventricles of patients with schizophrenia are approximately 130% the size of normal controls
What are ventricles?
the fluid-filled cavities within the brain that play important roles in supporting and protecting neural tissue, regulating cerebrospinal fluid (CSF) flow, and providing buoyancy to the brain.
What is the definition of discordant?
One has it, one doesn’t
What is the suggested cause of Sz?
Genetic predisposition
How does heritability affect Sz?
largest chance between twins not parents so suggests strong genetic link. However, rate from parents is higher than general population so may suggest environmental factor
How does prenatal environment affect sz?
Monochorionic (sharing single placenta) vs dichorionic (separate placenta) and found 60% mono concordance
What are other environmental factors affecting Sz?
Cannabis use, prenatal infection, childhood trauma, stress
How does the dopamine hypothesis affect Sz treatment?
People with sz have overactivity in dopamine neurons. Antipsychotics antagonise dopamine receptors and alleviate symptoms. Dopamine agonists induce positive symptoms.
Activity of dopamine neurons in accumbens strongly reinforce behaviour eg delusions caused by amygdala activity.
What does Stahl (2018) suggest about Sz treatment?
NMDA theory= Glutamate hypoactivity in regions involved with cognition and executive functions eg prefrontal cortex. Serotonin theory= Serotonin dysfunction may disrupt typical cognitive abilities prompting the SCZ development.
How are affective disorders categorised?
Mood disorder identified by disruptions in emotions
Why is Sz not considered an affective disorder?
due to unique clinical presentations, neurological underpinnings, treatment approaches
What are the 2 types of symptoms and examples of affective disorders?
Depression= low energy, loss of appetite, insomnia
Mania= euphoria, delusion, poor attention, grandeur
What are the 3 main types of affective disorders?
Bipolar disorder
Unipolar depression
Seasonal affective disorder
What are the characteristics of bipolar disorder?
Alternating periods of mania and depression, 1% affected, equally frequent in men and women
What are the characteristics of Unipolar depression?
Depression w/o mania, 2/3x more likely in women
What are the characteristics of seasonal affective disorder?
Depression associated w/ winter months
What can be said about the neurology and symptoms of affective disorders?
Unclear as no consistent markers
What can be said about the causes of affective disorders?
Clear link with genetic and environment so genetic predisposition
Rosenthal (1971) found x10 more likely to suffer if close relative also does
What are the treatments of affective disorders?
Monoamine hypothesis
Non pharmacological eg CBT
What does the monoamine hypothesis suggest about affective disorder treatment?
Suggests depression is caused by faulty activity of monoamine neurons eg deficiencies in serotonin, norepinephrine imbalance,
dopamine dysfunction.
What does the drug Iproniazid do in the body eg neurological, side effects?
(treats depression)
-Inhibits monoamine oxidase which increases serotonin, dopamine, norepinephrine
-Often has unpleasant side effects
What do Tricyclic antidepressants do in the body?
(treats depression)
-Agonist of just serotonin and norepinephrine
-Inhibits reuptake of neurotransmitter by terminal button.
What do SSRIs do?
(treats depression)
-Agonist of just serotonin
-Inhibits reuptake of just 5Ht
What does Reserpine do in the body?
(causes depression)
-Monoamine agnoist
-Causes depression but can be used to treat high blood pressure
