Neuropsychological Diseases Flashcards
(54 cards)
1
Q
What are 5 neuropsychological diseases?
A
- Epilepsy
- Parkinson’s Disease
- Huntingdon’s Disease
- Multiple Sclerosis
- Alzheimer’s disease
2
Q
What is the primary symptom of epilepsy?
A
- Recurrent seizures (intense neurological activity that originates in a specific region of brain) of endogenous pain
3
Q
What is the prevalence of epilepsy?
A
- Affects about 3.8% of population
4
Q
What are 4 causes of epilepsy?
A
- Brain damage
- Inflammatory processes
- Genes (over 100 known so far)
- Faults at inhibitory synapses (GABA, specifically GABAb receptors) -> excessive excitation
5
Q
How is epilepsy diagnosed?
A
- Electroencephalogram (EEG)
- See bursts of high amplitude spikes during seizures; single spikes between attacks
6
Q
What is a seizure?
A
- Sudden synchronous bursting discharge of neurons
7
Q
What are 2 types of behavioural changes with epilepsy?
A
- Convulsions: motor seizures with clonus (tremors), tonus (rigidity), loss of balance, loss of consciousness
- Subtle: changes in mood, thought, behaviour
8
Q
What are focal seizures?
A
- Specific focus of origin
- Simple vs. complex
9
Q
What are generalized seizures?
A
- Originates in multiple sites
- Absence (petit mal) vs. Tonic-clonic (grand mal)
10
Q
Describe simple focal seizures?
A
- AKA Jacksonian seizures
- Symptoms are primarily sensory or motor or both
- Symptoms spread as epileptic discharge spreads through different brain regions
11
Q
Describe complex focal seizures?
A
- Often restricted to temporal lobes
- Patient engages in compulsive and repetitive simple behaviours (automatisms)
- More complex behaviours almost normal
12
Q
What are 6 examples of symptoms in simple partial seizures?
A
- Somatosensory: tingling of contralateral limb, face, or side of body
- Focal motor: tonic-clonic movements of upper/lower limb
- Contraversive: head/eyes turned to opposite side
- Autonomic: sweating, flushing, nausea
- Auditory: hears ringing, hissing or noises
- Visual: sees flashes of light, scotomas, blurring
13
Q
What do the symptoms of complex partial seizures look like?
A
- Multiple symptoms of simple partial seizures
- Complex hallucination
- Undoing buttons of shirt
- Loss of consciousness
- Whole videos replaying in mind
14
Q
Describe tonic-clonic seizures?
A
- Loss of consciousness and equilibrium
- Violent tonic (rigidity) - clonic (tremors) convulsions
- Resulting hypoxia may cause brain damage (loss of consciousness)
15
Q
What are absence seizures?
A
- Not associated with convulsions
- Absences: disruption of consciousness with cessation of ongoing behaviour
- Bilaterally symmetrical EEG
16
Q
What are auras?
A
- Peculiar subjective experiences (e.g. smell, hallucination, feeling)
- Often precede seizures (warning)
- Nature suggests site of epileptic focus (ex. olfactory)
17
Q
What is kindling?
A
- The progressive development of convulsions with a series of periodic electric or chemical brain stimulations
- Currents that induce some degree of stimulation locally
- Neural changes are permanent
- Produced by stimulation distributed over time
- Extensive kindling -> spontaneous convulsions
18
Q
How can kindling be used as a model for epilepsy?
A
- Convulsions are similar to human’s
- Human post-traumatic epilepsy follows a similar progressive onset
- BUT it is not spontaneous
19
Q
How prevalent is Parkinson’s disease?
A
- About 1% of population (higher in males)
- Mostly middle and old age (#1 risk factor)
20
Q
What are some symptoms of Parkinson’s disease?
A
- Slow movements, tremor during inactivity (disappears with voluntary movements), difficulty initiating movements, muscle rigidity, reduced facial expression
- Pain and depression are common
- No single cause
21
Q
What is Parkinson’s disease?
A
- Degeneration of dopaminergic neurons in substantia nigra
- Loss of dopamine release (and therefore loss of neurons) in the striatum of basal ganglia
- Autopsies reveal Lewy bodies (protein clumps) in substantia nigra
22
Q
What are some treatments of Parkinson’s disease?
A
- L-dopa, DA agonists
- > for early stages
- > dyskinesia is a possible side effect
- Deep brain stimulation of STN
- > buys time
- > mitigate symptoms
23
Q
Which dopaminergic tract tends to be affected in Parkinson’s disease?
A
- Nigrostriatal tract
24
Q
How do genetics influence Parkinson’s disease?
A
- 80% idiopathic (no known cause)
- 15% familial/inherited
- 5% a known mutation
25
What is Alpha-synuclein?
- Main component of Lewy bodies
- Single nucleotide mutations are uncommon
- Multiplication mutations = 2% of familial cases
26
Which 3 mutations have had the most research in the genetics of Parkinson's disease?
- Alpha-synuclein
- Dardarin protein
- Parkin
27
What is the MPTP model of Parkinson's disease?
- 'synthetic heroin'
- MPTP causes cell loss in substantia nigra, and reduced dopamine release in the striatum
- MPTP is mostly a primate model
- MPTP used to develop dopaminergic drugs for PD
28
What is Huntington's disease?
- A rare progressive motor disorder of middle/old age with a strong genetic basis
- AKA Chorea
- Begins with fidgetiness and progresses to jerky movements of entire limbs and severe dementia
- Death usually occurs within 15 years
- Clumps of proteins within brain
- No cure
29
What causes Huntington's disease?
- Caused be a single dominant gene
| - Huntingtin gene -> Huntingtin protein
30
When do the first symptoms of Huntington's disease usually appear?
- Age 40
31
Where does Huntington's disease originate?
- Basal ganglia
| - Leads to tissue loss in brain (see larger ventricles)
32
What does 'multiple sclerosis' mean?
- Multiple hardenings
33
What is multiple sclerosis?
- Progressive loss of CNS myelin (autoimmune)
- Eventually neuronal degradation
- Early onset -> progressive
- Periods of remission are common
34
What are some advanced symptoms of multiple sclerosis?
- Visual disturbances
- Muscle weakness
- Numbness
- Tremor
- Loss of motor coordination (ataxia)
35
Is there a cure for MS?
- No cure
| - Drugs (mostly immunomodulators) may retard progression/block symptoms
36
What are some causes of multiple sclerosis?
- Genetic predisposition
- Environmental factors
- Epigenetic influences
37
Describe the genetic factors of MS?
- 25% concordance in monozygotic twins
- 3x higher in females
- 0.15% greater in Caucasians
- Several genes
- Several non-coding RNAs (regulation of genes)
38
What environmental factors contribute to MS?
- Climatic zone (> childhood in cold climates)
- Viral or bacterial infections (e.g. Epstein-Barr virus for mononucleosis)
- Life style (smoke, diet, sun exposure)
39
What epigenetic influences may play a role in MS?
- Vitamin D and other chemicals
| - Vit D seems to help symptoms in some studies
40
Where is the highest rates of MS in the world?
- Orkney islands off of Scotland
41
What is the most common cause of dementia?
- Alzheimer's disease
42
Describe Alzheimer's disease?
- Age-related (10% over 65 and 35% over 85)
- Progressive
- Microbleeds also common
43
What are some early symptoms of Alzheimer's?
- Confusion
| - Selective decline in memory and attention
44
What are some late symptoms of Alzheimer's?
- Massive neurological impairment (e.g. bladder, motor control)
45
How is Alzheimer's disease diagnosed?
- Definitive diagnosis only at autopsy
- Loss of neurons
- Neurofibrillary (tau) tangles
- Amyloid plaques
46
Where does Alzheimer's disease begin?
- Regions involved in learning/memory
| - Ex. Posterior parietal cortex, Inferior temporal cortex, hippocampus, entorhinal cortex, amygdala, prefrontal cortex
47
Describe the neurobiology of early onset/familial Alzheimer's disease?
- Mutations in 3 specific genes for variants of amyloid proteins or their regulators
48
Why is Alzheimer's disease more common in those with Down syndrome?
- Beta-amyloid gene is found on chromosome 21, which there is a trisomy of in Down syndrome
49
How does late-onset Alzheimer's disease occur?
- Mutations in several (15+) genes for amyloid or tau proteins
50
What is the pathogenic spread hypothesis?
- Can tau-neuron transfer to healthy neuron?
| - Begin in temporal lobe and spread
51
What are some treatments for Alzheimer's disease? Can Alzheimer's disease be cured?
- No cure (reduce symptoms)
- Decline in ACh levels (ACh agonists help)
- Immunotherapy (against amyloid proteins)
- Reducing inflammation has been effective in animal models
52
What does 'transgenic' mean?
- Animals with the genes of another species
53
What is the transgenic mouse model of Alzheimer's disease?
- Only humans and a few related primates spontaneously develop amyloid plaques
- Genes for rapid human amyloid synthesis introduced in mice
- Genes for human tau protein into mice
- Some can express both (which is the best model)
- Individually, can help explain contributions of each
54
How does the proximity to amyloid plaques affect neuronal response?
- Neurons found closer to amyloid plaques have altered activity
- Farther = more normal neurons
