Flashcards in 10: Brain Plasticity Deck (22)
In what period is there rapid neuron growth in children?
Birth to 2 years old
What determines if a synapse is pruned?
How much it's used and how effective it is
What is the main difference in the number of synapses in the visual cortex for blind people?
They have more synapses as they're unable to prune out ineffective connections
What is hebbian modification?
neurons that fire together, wire together
Neurons that fire out of sink lose their link
When does pruning take place?
Around the age of 2 or 3
What is a hemispherectomy?
Early removal of a brain hemisphere
What is the effect of removing a brain hemisphere in early life?
There is little effect as the brain can adapt
Can be a few issues with movement
How does plasticity change in adulthood?
The brain can still reorganise as a result of learning from experiance
What are the two forms of plasticity in adulthood?
What is the function of the homunculus?
Maping the body onto the sensory and motor cortexes
There is the same basic layout but a lot of individual differences in how it's organised
What was the study with musicians which explained why we have differences in body mapping?
String players had a larger and stronger brain activation to sensations on their fingers than a control group because they've been using them for so long. Their brain has adapted
Correlates with how early they learnt to play the instrument
What was found about finger representations in blind people that used three fingers to read braille?
The mapping for the 3 fingers overlapped so they were unable to tell which finger the sensation was occuring on
What adaptations are made in the brain's of blind people?
More space donated to sound and touch instead of sight
What evidence is there of cross modal activity in blind people?
When reading braille, the visual cortex was activated as it has taken over that function
How do strokes demonstrate plasticity in the adult brain?
Motor and cognitive function can be recovered in the proceeding 3 months
What is the mechanism of plasticity in adults?
Long term potentiation
Repeated neuron fire strengthens the synapse
What was Draganski's 2004 study into the brain and learning?
When adults spent 3 months learning to juggle, their hippocampus got bigger which shows how we can change our brain structure through experiance and learning
How are stem cells linked to plasticity?
neural stem cells (Spinal cord) generate neural progenitor cells which create new neurons
New neurons take about 2 months to mature
What things aid neurogenesis?
What things inhibit neurogenesis?
How is exercize linked to plasticity?
rats given a running wheel had improved cognition
Also seen in adults aged 65