Neurological disorder Flashcards
Define excitotoxicity.
Neurons can be become over-excited which leads to damage.
Do neurons self-replicate?
No: loss of neurons is a problem.
Define an a) intrinsic and b) extrinsic disorder?
a) Caused by genetics
b) Caused by external factors
Seizures are always caused by intrinsic factors. True or false?
False: they can be caused by a combination of the two.
If new neurons are born, where is this from?
Neural stem cells in the hippocampus or olfactory bulb.
Disruption of energy supply to a neuron can cause cell death. True or false?
True.
Neural circuits are refined over many years of usage. Why is it so damaging to lost this?
It cannot be exactly replicated.
Neurological disorders fall into 2 categories, a) extrinsic or b) intrinsic. Give examples of each?
a) Tumours, traumatic brain injury, infection (e.g. BSE), stroke
b) developmental abnormalities (Down’s), degeneration (Alzheimer’s)
Define a seizure.
‘Overly synchronous brain activity’
Seizures occur in which life stages?
Childhood or possibly old age: the times when most brain changes occur
What percentage of epileptic disorders have genetic causes?
30%
What percentage of epileptic disorders have acquired causes, e.g. head traumas etc.?
25%
Seizure disorders can be split into 2 categories. What are they?
- Generalised: no apparent local onset
2. Partial: begin from a focal point
What are the 3 types of generalised seizure and what do they do?
- Tonic-clonic: affects the whole brain. Largely associated with epilepsy.
- Absence: lapses of awareness often characterised by staring. Often go undetected.
- Atonic: a sudden loss of muscle tone causing temporary paralysis
What is another name for a) tonic-clonic and b) absence seizures?
a) Grand mal
b) Petit mal
Partial seizures are often characterised by a series of movements. Why?
Begins from a localised point, but as the seizure spreads along the primary motor cortex you can detect this progression in the person’s movements. Also it spreads to other cortices like the sensory, psychic and autonomic regions which you can see as the person may begin to lose vision, become emotional and begin to sweat or salivate.
The progression of partial seizures reflects cortical maps. True or false?
True.
Genetic defects that cause seizures often affect what?
Ion channels, thus altering the excitability of neurons.