Brain Plasticity - Brian Damage And Neuroplasticity Flashcards
Proliferation
Production of new glia cells and neurons in the brain primarily occurring early in life
Migration
Movement of the new neurons & glia cells to their eventual locations
Differentiation
Forming of the axon & dendrite that gives the neuron its distinctive shape
Myelination
Process by which glia produce the fatty sheath that cover the axons of some neurons
Synaptogenesis
Formation of the synapses between neurons
Development of the brain
Originally thought new neurons were not formed after initial development
Research indicated otherwise:
-stem cells are undifferentiated cells found in the interior of the Brian that generate “daughter cells” which can transform into glia or neurons
New olfactory receptors also continually replace new ones
The Brian also has the ability to reorganise itself in response to experience
axons & dendrites continue to Modify their connection throughout time Dendrites continually grow spines Found as a function of physical activity Declines in cerebral cortex in old age much less in those that are physically active
Neurons become more finely tuned & responsive to experiences
E.g - blind people often l often have enhanced tactile senses & inc verbal skills
Extensive practice of a skill changes the brain in a way that improves the ability for that skill
E.g Mri reveal temporal lobe of prof musians in right hemisphere 30% larger
Grey matter responsible for hand control & vision
Causes of Brian Damage
Brian Tumours
Mass of cells growing independent to the body
Cerebrovascular Disorders
Strokes are sudden-onset cerebrovascular disorders
Closed Head injuries
Contusions
Concussion
Infections of the brain
-Bacterial
Meningitis
Syphills
Viral infections
Rabies
AIDS
Neurotoxins
Neuropsychological disorders
Genetic factors -Down Syndrome extra chromosome Epilepsy Seizures Parkinson's disease Movement disorder 5% of population Multiple Sclerosis - progressive disease Alzheimer's - most common cause of dementia Huntington's disease Single dominant disease
Plasticity After Brain Damge
Degeneration
Regeneration
Reorganisation
Recovery of Function
Neural Degeneration
Degeneration of distal segment - of a cut axon between the cut and the synaptic terminals
Retrograde is the degeneration of proximal segment - cut axon between cut and the cell body
Neural regeneration
Nerve damage without severing the Schwann cell sheaths regenerate to correct targets
When slightly Separated axons often regenerate incorrectly
When widely separated no typical regeneration
Neural organisation
Strengthening of existing connection through release of exhibition
Establishment of new connection by collateral sprouting
