Dopamine Deficiency
dopaminergic drugs are ineffective in many
- not all schizophrenic people have excessive dopamine
- side effect of antipsychotic drugs is Parkinson’s like symptoms
Tardive Dyskinesia
tremors and involuntary movements due to long term blocking of dopamine receptors
- happens when you take anti-dopamine drugs
- even after you stop taking it, these symptoms continue for around a year after, creates long term changes
Neuroleptics
atypical or second-generation antipsychotics block receptors less strongly and target other, non-dopamine receptors
Glutamate Theory
hypo function of NMDA receptors; increases in glutamate, increases in dopamine
- this increases positive ND negative symptoms of schizophrenia
Brain Malfunctions in Schizophrenia
brain tissue deficits create ventricular enlargement
- hypofrontality
- decreases in temporal and frontal lobes
- increases activity in orbital frontal cortex and parts of the hippocampus
Wisconsin Card Sorting Test
test for hypofrontality
- requires individuals to change strategies mid- stream
ie; sort these by cloud and then half wa through, you are told to switch to sorting them by even or odd
- schizophrenic patients have less activity in frontal lobe and therefore have troubles switching due to the frontal lobes role in long term planning
Neurological Anomalies in Schizophrenia
Winter Birth Effect
more patients with schizophrenia were born in the winter months than the summer months
- winter and spring months
- rates of schizophrenia peak during a particularly high influenza season
Interleukin 1 Beta Level
protein released by the body
- schizophrenic patients have more of this
- we believe this is due to maternal infection during second trimester
Affective/ Mood Disorders
depressive disorders, mania, bipolar disorders
Depressive Disorders
intense sadness and loss of interest
- circadian rhythm is controlled by genes; these genes are messed up
Mania
excessive energy and confidence
Bipolar Disorders
alternate between depression and mania
Reactive Depression
occasional intense sadness in response to life challenges
Major (unipolar) Depressive Disorders (MDD)
intense sadness for long periods of time
- sad to the point of hopelessness at weeks at a time, enjoy ability to enjoy the great things in life
cognitive symptoms- slowness of thought, sleep disturbances, memory impairments
Mania Symptoms
Must have 3 or more symptoms, must be debilitating, and not caused by drugs
Bipolar 1
alternated between periods of depression and full-blown mania
- often includes psychotic features such as delusions, hallucinations, paranoia, or bizarre behaviour
Bipolar 2
alternate between periods of depression and hypomania
Hypomania
the extreme opposite of mania symptoms
Cyclothymia Disorder
cycle between depression and mania very quickly
- by days or hours
Dopamine and Serotonin in Bipolar
increased sensitivity to dopamine, decreases sensitivity of serotonin or more general dysregulation of dopaminergic system
Drug Treatments of Bipolar Disorder
second- generation antipsychotics
- lithium; reduces mania and limits depressive episodes
- carbamazepine and valproate
Heredity of Affective Disorders
partly heritable
- 37% heritability overall, but more in women than men
- prominent environmental antecedents of depression involve stress
- despite similarities, depression and bipolar disorders are genetically independent
Rhythms and Affective Disorders