9- Plasticity in Specific Brain Regions Flashcards
How can the motor cortex be mapped?
By TMS
What is the consequence of the TMS coil being over the motor cortex?
Triggers muscle activity
What does moving the TMS coil around across the motor cortex cause?
Activation of different muscles
What can TMS on the motor cortex generate?
A map of someone’s motor cortex
What suggests plasticity based on personal use?
Individual differences in body representation in the somatosensory and motor system
What studies tell us about plasticity?
Studying sensory disruption
When can sensorimotor areas reorganise?
If the input is changed
What does studying finger representations in congenital syndactyly show?
Motor cortex adapts itself based on the inputs coming in
How was use-dependent plasticity studied?
Seeing if playing a musical instrument changes the motor cortex
What did tactile stimulations of digits of left hand cause in musicians when ‘use-dependent plasticity’ was investigated?
Brain activity was shifted and greater strength of response
What was there correlation between when investigating use-dependent plasticity and what was this evidence of?
Correlation between experience and size of change, evidence for expansion of cortex
What does the auditory cortex contain?
Graded representation of sound frequencies
How is the auditory cortex different in the blind sighted?
Enlarged
What did blind participants show when having to localise a sound source at peripheral locations?
Better detection performance
What is activated in a blind person during Braille reading by touch?
Visual cortex
How does Braille reading activating the visual cortex suggest a change in function in blind people?
Visual cortex is being used for reading
How is TMS used to demonstrate cross-modal plasticity?
To disrupt visual cortex function
What does disruption of the visual cortex cause in blind individuals?
Braille reading errors and distorts touch perceptions
What is the effect of disrupting the visual cortex in controls?
No effect
How can the motor cortex reorganise?
To support motor skills
What is shown by studies in blind individuals?
Plasticity in other brain regions
What expansion is shown by studies of blind individuals?
Expansion of the auditory cortex
What does plasticity lead to?
Better performance
What can provide useful insights into plasticity mechanisms?
Motor learning
How does motor learning and motor cortex reorganisation occur?
Rapidly
Plasticity also occurring in the adult brain shows what?
Plasticity is maintained through the lifespan
What do TMS studies show?
Even simple movements can cause rapid reorganisation of motor cortex
What is an example of injury-induced plasticity?
Motor cortex reorganises itself after stroke damage
What is the brain’s response to practicing movements?
Motor cortex can rapidly reorganise itself
What is the key mechanism in adult plasticity?
Long-term potentiation
What causes brain plasticity?
Changes in synaptic weighting
How does long-term potentiation cause connection between 2 neurons to become stronger?
A neuron repeatedly fires and excites another neuron
What does long-term potentiation cause at the synapse?
Long-term strengthening of transmission
What causes a bigger response in a second neuron?
Same input
What is based on LTP?
Use-dependent plasticity in the motor system
What does LTP depend on?
Activation of NMDA receptors
What is the result of drugs blocking NMDA activation?
They prevent reorganisation of motor cortex after training
When does plasticity occur?
In adulthood as well as childhood
What is use-dependent plasticity?
Cortex reorganisation occurring in response to experience
What is injury-induced plasticity?
Cortex reorganisation occurring in response to injury
What is a functional consequence of plasticity?
Improved performance
What is important for reorganisation?
Synaptic plasticity
