Mental Illness Flashcards
What is neurology
Is a branch of medicine concerned with the diagnosis and treatment of nervous system disorders
What is psychiatry?
Branch of medicine concerned with diagnosis and treatment of disorders that affect the mind
What two interacting factors produce the brain?
Heredity and environment
What two assumptions are Freud’s theory of psychoanalysis based on?
- Much of mental life is unconscious
- Past experiences shape how a person will feel and respond throughout life
Describe behaviourism?
Focuses on observable behaviours and their control by the environment
What major psychiatric disorder occurred during Freuds time?
General paresis of the insane
What is the course of general paresis of the insane?
Progressive
Symptoms of mania ( excitement, euphoria, and grandiose delusions) to cognitive deterioration and ultimately paralysis and death
What caused general paresis of the insane?
Treponema pallidum - microorganisms that cause syphilis
What does a dietary deficiency in niacin (vitamin B) cause?
Agitation, impaired reasoning and depression
What does HIV do to the brain?
Causes progressive cognitive and behavioural impairments
Describe molecular medicine
The approach of using genetic information to develop treatment
What is pathophysiology?
Discovery of abnormal physiological condition
What are the challenges for molecular medicine in treating brain diseases?
- Relies on patient description of symptoms
- Not all have a clear genetic basis and those that do have a large pool of implicated genes.
What are induced pluripotent stem cells?
Stem cells with the potential to differentiate into any cell type, including neurons, that are chemically transformed from mature cells derived from a person
What is the most common psychiatric disorders?
Anxiety disorders
Describe panic disorder
Frequent panic attacks consisting of discrete periods with the sudden onset of intense apprehension, fearfulness, or terror, often associated with feelings of impending doom.
Describe agoraphobia
Anxiety about, or avoidance of, place or situations from which escape might be difficult or embarrassing, or in which help may not be available in the event of a panic attack.
Describe generalised anxiety disorder
At least 6 months of persistent and excessive anxiety and worry
Describe specific phobias
Clinically significant anxiety provoked by exposure to a specific feared object or situation, often leading to avoidance behaviour
Describe social phobias
Clinically significant anxiety provoked by exposure to certain types of social or performance situations, often leading to avoidance behaviour
What are the symptoms of a panic disorder?
Palpitations, sweating, trembling, shortness of breath, chest pain, nausea, dizziness p, tingling sensations and chills or blushing
What is the stress response?
Is the coordinated reaction to threatening stimuli
How is the stress response characterised?
Avoidance behaviour
Increased vigilance and arousal
Activation of the sympathetic division of the ANS
Release of cortisol from the adrenal glands
What two structures help regulate CRH neurons in the hypothalamus?
Amygdala
Hippocampus
How does the amygdala and hypothalamus contribute to anxiety disorders?
Hyperactivity of the amygdala
Diminished activity of the hippocampus
What neurons activate the HPA axis and the stress response?
Bed nucleus of the stria terminalis.
What is psychotherapy?
Gradual increase to fear stimuli. To alter connections in the brain
What are anxiolytic drugs?
Medications that reduce anxiety by altering chemical synaptic transmission in the brain
What major types of the drugs are used in the treatment of anxiety disorders?
Benzodiazepines
Serotonin-selective reuptake inhibitors
How does Benzodiazepines work?
They bind to GABA A receptor and act to make GABA more effective in opening the Cl- channel and producing inhibition.
How do PET scans differ in benzodiazepines binding in normal and panic disordered brains?
Fewer binding sites present in frontal cortex of panic disordered brain.
How do SSRIs work?
Prolong the actions of released serotonin at their receptors by inhibiting reuptake
Describe affective disorders
Disorder of mood
What are the symptoms of depression?
Loss of appetite
Insomnia
Fatigue
Feelings of worthlessness and guilt
A diminished ability to concentrate
Recurrent thoughts of death
What is bipolar disorder?
Repeated episodes of mania
What are the symptoms of bipolar disorder?
Inflated self esteem or grandiosity
A decreased need for sleep
Increased talkativeness or feelings of pressure to keep talking
Flight of ideas, or a subjective experience that thoughts are racing
Distractibility
Increased goal directed activity
What is the difference between type 1 and type 2 bipolar disorder?
Type 1 - mania
Type 2 - hypomania, generally associated with major depression
What is the role of reserpine
Depletes central catecholamines and serotonin by interfering with their loading into synaptic vesicles
What role does monoamine oxidase (MAO) play?
Enzyme that destroys catecholamines and serotonin
What is the role of imipramine?
Inhibits the reuptake of released serotonin and NE thus promoting their action in the synaptic cleft
What is the monoamine hypothesis of mood disorders?
A hypothesis suggesting that depression is a consequence of a reduction in the levels of monoamine neurotransmitters, particularly serotonin and NE, in the brain
What is diasthesis?
Predisposition for a certain disease
What is the diathesis-stress hypothesis of affective disorders?
HPA axis is the main site where genetic and environmental influences converge to cause a mood disorder
What does injected CRH into the brains of animals produce behaviourally?
Symptoms similar to depression - insomnia, decreased appetite, decreased interest in sex, increased behavioural expression of anxiety,
How are glucocorticoid receptors influenced in early childhood?
Number regulated by early sensory experience
Loving environment - tactile stimulation activates the ascending serotonergic inputs to the hippocampus = increased receptors
Neglectful environment - no growth in receptors
How does the anterior cingulate cortex affect depressed patients?
Link between an internally generated emotional state and the HPA axis
What is the most effective treatment for depression and mania?
Electroconvulsive therapy
What are the advantages and disadvantages of ECT?
A - fast acting
D - memory loss and impairment of new information storage
What is psychotherapy?
Overcome negative views on themselves and their future,
What are four antidepressant drugs?
- Tricyclic compounds such as imipramine (blocks reuptake of NE and 5-HT)
- SSRIs e.g. fluoxetine
- NE and 5-HT selective reuptake inhibitors e.g. venlafaxine
- MAO inhibitors to reduce enzymatic breakdown of NE and 5-HT e.g. phenelzine
How do antidepressant drugs work?
Dampens hyperactivity of HPA and anterior cingulate cortex.
Increased glucocorticoid receptor expression in hippocampus
How does lithium affect neurons?
Prevents normal turnover of phosphatidyl inositol (PIP2)
Interferes with adenylyl cyclase which generates cAMP and glycogen synthesise kinase,
How is schizophrenia characterised?
Loss of contact with reality and a disruption of thought, perception, mood and movement
What are the positive symptoms that reflect the presence of abnormal thoughts and behaviours in schizophrenia?
Delusions
Hallucinations
Disorganised speech
Grossly disorganised or catatonic behaviour
What are the negative symptoms that reflect the absence of responses that are normally present in schizophrenia?
Reduced expression of emotion
Poverty of speech
Difficulty in initiating goal directed behaviour
Memory impairment
What causes schizophrenia?
Genetics
Environmental factors
Viral infections during fetal and infant development - contributing cause
Poor maternal nutrition - contributing cause
What changes are seen in the schizophrenic brains?
Larger ventricles
Defects in myelination in cerebral cortex
Reduced cortical thickness and abnormal neuronal lamination.
What is the dopamine hypothesis of schizophrenia?
Psychotic episodes are triggered specifically by the activation of dopamine receptors.
Two systems: ventral tegmental area and substantia nigra (control of voluntary movement by striatum)
What are neuroleptic drugs?
Potent blockers of dopamine receptors , specifically the D2 receptor
E.g. chlorpromazine
What is the glutamate hypothesis of schizophrenia?
Reflects diminished activation of NMDA receptors in the brain
What drugs affect glutamate receptors?
Phencyclidine (PCP) and ketamine
Entering NMDA channel and clog the pore
What drugs reduce the positive symptoms of schizophrenia?
Chlorpromazine and haloperidol
