Brain Plasticity Flashcards
Neural Plasticity
Refers to the manner in which the brain changes in response to stimulation from the environment.
Developmental Plasticity
Changes in the brains neural structure during its growth and development (maturation).
Developmental Plasticity: Key Processes
- Proliferation
- Migration
- Circuit formation (synaptogenesis)
- Synaptic pruning
- Myelination
Proliferation
Unborn baby’s neurons divide and multiply at a rapid rate.
Migration
New neurons in the foetus and newborn move to their location in the nervous system.
Circuit Formation (Synaptogenesis)
Creation of multiple connections between neurons.
Synaptic Pruning
The removal of connections that have not formed strong pathways and are no longer needed.
Myelination
Development of thick myelin sheaths which speeds up neural transmission. This process continues through to very late adolescence.
Infancy and Adulthood
Neuroscientists have identified infancy and adolescence as two periods of significant change due to developmental plasticity.
- Our synaptic density is greatest from the end of infancy to early childhood.
- The adult brain has 40% less synapses than the number in a three year old.
Frontal Lobe Development
Our brain continues to develop until about 25 years of age. The last area of the brain to mature and undergo myelination and synaptic pruning is the frontal lobe.
- The prefrontal cortex is the last to develop and is responsible for higher-order decision making and reasoning.
Developmental Plasticity
- Sensitive period
- Critical period
Sensitive Period
The period of time when an organism is more responsive to certain stimulation.
- Lack of stimulation over this period can lead to long term deficits.
Critical Period
The narrow period of time where development in an animal is preprogrammed for learning to occur.
Experience Expectant Development
Brain is primed (i.e. it expects) to make neural changes provided it gets the correct input.
e.g. Hearing language during the sensitive period.
Experience Dependent Development
Not related to sensitive periods and the brain is not primed to make neural changes. Refers to the creation and organisation of neuron connections that occur as a result of a persons life experiences.
