Lecture 24 Flashcards
What are positive symptoms of schizophrenia?
Delusions, hallucinations, disordered thought and speech
What are negative symptoms of schizophrenia?
Flat effect, alogia, anhedonia, asociaity, avolition
What is alogia?
Lack of additional, unprompted content in normal speech
What is anhedonia?
Inability to feel pleasure in normally pleasurable activity
What is avolition?
The decrease in the motivation to initiate and perform self-directed purposeful activities
What is schizophrenia usually associated with?
Depression, substance abuse, suicide and life expectancy reduced by 10-12 years
What is the pathology of schizophrenia?
Increased levels of dopamine in the mesolimbic pathway
What is the incidence of schizophrenia?
0.6% of population worldwide!
Can start at any age, peak onset early twenties
What are the causes of schizophrenia?
Genetics: 50% concordance in monozygotic twins (DISC1)
Environment: 50% concordance in monozygotic twins
Developmental: infection in utero, poor diet, asphyxia
Social factors: environment, stress relationships
Drug abuse: e.g. cannabis, cocaine, (cause or effect?)
Dopamine hypothesis (excessive D2R stimulation)
Reduced NMDAR function
What do mice with reduced NMDAR function exhibit?
Excessive motor activity
Stereotypy (continuously pacing around etc)
Deficits in social and sexual interactions (Excape behavior is exaggerated in mutated mice)
Symptoms that are ameliorated by typical and atypical antypsychotics
What consists of the mesolimbic pathway?
Substantia nigra stimulates the striatum
Ventral tegmental area stimulates the frontal lobe
What are treatments for schizophrenia?
Antipsychotics (typical and atypical) more effective in treating positive symptoms
Intense psychotherapy, social support
Recovery and improvement in symptoms in over 50%
What are symptoms of depression?
Lowered mood Anhedonia Avolition Altered appetite Hyposomnia/Hypersomnia Worthlessness and guilt Reduced ability to concentrate Recurrent thoughts of death Reduced life span 3-7% risk of suicide
What is the pathology of depression?
Reduced hippocampal volume
Vascular lesions
Reduced BDNF
What is the incidence of depression?
3% Japan, 18% USA - average 10%
May not reflect actual people with depression but attitudes toward depression
Women are twice as affected as men
Massive cost to society
What is defined as a stroke?
Neurological deficit of cerebrovascular cause that persists beyond 24 hours or is interrupted by death within 24 hours
How is a stroke different from a transient ischaemic attack?
Transient ischemic attack has stroke-like symptoms but resolve within 24 hours
- Brain function ceases 60-90 seconds of an ischaemic event
- irreversible brain damage if ischaemic event > 3 hours duration
- neurological deficit related to site and extent of damage
What are two main types of stroke?
Ischaemic and Haemorrhagic
What are types if ischaemic strokes?
Embolus (wandering clot)
Thrombus (locally-formed clot)
Systemic hypoperfusion (e.g. heart)
Venous thrombosis
What is the definition of a haemorrhagic stroke?
Entry of blood into CNS via rupture of blood vessel/sinus or an aneurysm
What are types of haematomas in the brain?
Epidural
Subdural
Subarachnoid
Intracerebral
What is an epidural haematoma?
Traumatic damage to a meningeal artery of dural venous sinus (e.g. blow to the head)
What is a subdural haematoma?
Caused by rapid movement of head causing tearing of the cerebral vein as it enters a dural venous sinus
What is a subarachnoid haematoma?
Is caused by damage (e.g. aneurysm) to a cerebral artery or into the subarachnoid space
What is an intracerebral haematoma?
Cause by damage of a blood vessel within the brain
What is the incidence of stroke?
10% of deaths worldwide
2nd leading cause of death (1st heart disease, 3rd cancer)
95% occur in people over 45 years of age
What are risk factors for stroke?
High blood pressure - disputable - why it is a risk factor is unknown High cholesterol Diet Physical inactivity Drugs of abuse (alcohol, cigarettes, cocaine, amphetamine)
What are treatments for stroke?
Preventative - Antocoagulants; carotid angioplasty - Endarterectomy; diet/lifestyle Acute ischemic - thrombolysis (tissue plasminogen activators (within 3 hours); thrombectomy, angioplasty, stenting) Acute haemorrhagic - surgery Chronic post stroke - control of hypertension; aspirin; physical and occupational therapy
What are symptoms of Alzheimer’s?
Short-term memory loss
Progressive apathy, confusion, irritability, mood swings, long-term memory loss, withdrawal, loss of bodily functions, death within 7 years of diagnosis
What is the pathology of Alzheimer’s?
Profound loss of neurons
Plaques (amyloid)
Neurofibrillary tangles (hyperphosphorylated tau)
What is the incidence of Alzheimer’s?
1.5-2%
Worldwide cost: 160 billion USD per year
What are causes of Alzheimer’s?
Age: 10% over 65, 50% over 85
Genetics but predominantly for early onset e.g. ApoE4 gene variant
Trauma e.g. stroke
High blood pressure/hypercholesteremia (but statins ineffective)
Environemental factors e.g. food Aluminium, supplements in coffee drinks
What are treatments for Alzheimer’s?
Treating symptoms:
Acetyl cholinesterase inhibitors, NMDAR antagonists e.g. memantine
Against risk:
NSAIDs and caffeine intellectual stimulation, diet and exercise
