Neuroplasticity Flashcards
Define neuroplasticity
- The process by which the brain changes based on what has happened to it.
- Specifically, it is the brains ability to re-organize itself by forming new connections throughout life by allowing neurons in the brain to adjust their activities to new situations or to changes in the environment.
- Term is also use frequently to consider how the brain may compensate for injury and disease.
How do connections strengthen in neuroplasticity?
The dendrites (made up of gray matter as well as cell bodies) extended and form stronger connections with other neurons. They receive messages from synapses and strengthen connection for extensive repetition or learning. When we learn network of dendrites grow higher and higher and new one spout from existing dendrites.
What is the neuroplasticity and behaviour involved in the Maguire (2000) + Luby et al (2013)
[Developmental changes/Synaptic pruning/learning and memory/Negative experiences]
Developmental changes - By the time an infant is two, the number of synapses is approximately 15,000 synapses per neuron (twice the average adult brain). Then synaptic pruning occurs when we age.
Synaptic pruning - Synaptic plasticity enable to process of a eliminating weaker synaptic contacts while stronger connections are kept and strengthened based on experience. Connections to have been activated most frequently are preserved.
Learning and memory - The brain changes when learning and that is due to its plasticity
Negative experiences - Research has shown that trauma or negative experiences can limit or change the way the brain develops compared to if it did not have these experiences.
Aim of Luby
To investigate whether poverty experienced in early childhood impacts brain development at school age and to explore the mediators of this effect.
Method of Luby
- 145 right-handed children
- Cognitively and socially assessed annually for 3-6 years before they underwent 2 MRI scans (whole bain and amygdala).
- Scans measured brain volumes of white and cortical grey matter and volumes of hippocampus and amygdala
- Support or hostility of caregivers were noted
- Existence of stressful life events experienced was a variable of measure
Findings of Luby
- Poverty was associated with less white and grey matter and with smaller hippocampus and amygdala volumes.
- Whether the caregiver was supportive or hostile mediated the effects poverty on both hippocampi,
- stressful life events affected the volume of the left hippocampus only.
Conclusion of Luby
Exposure to poverty in early childhood impacts brain development at school age draws attention to the effects of poverty on child development.
Finding that these effects on the hippocampus are mediated by caregiving and stressful life events suggest that attempts to enhance early caregiving should be a focus.
Researcher observed dendritic atrophy in the children as well as in rodents.
Maguire to neurplasticity
Taxi drivers has the ability to memorize locations due to extensive training making new synaptic connections. It is also frequently active as they drive so they are preserved.
What can neural pruning and neural network be asked in?
Only in SAQ
What is neural pruning
- Process of synaptic contacts being removed based on how often they are used
Our brain changes in various ways
- One of the ways that our brains change is through the creation of neural networks.
- This happens because of long-term potentiation - that is, the repeated firing of neurons.
- This leads to an increase in dendritic branching which leads to an increase in the number of synapses.
- a way that our brain can change is through neural pruning - which is a decrease in the number of synapses as a result of the removal of dendritic branches.
- Pruning can be the result of neuron cell death, hormones such as cortisol or the lack of use of a neural pathway.
- The exact mechanism of neural pruning is not yet fully understood.
What is neural network
- Neural networks are created when a neuron or set of neurons are repeatedly stimulated by an action potential travelling down the axon
- This repeated firing of the neurons, called long term potentiation, results in gene expression which causes the neurons to sprout new dendrites – known as dendritic branching.
- This increases the number of synapses available for the behaviour.
- The branching of neurons in the brain is called grey matter.
- Dendritic branching can be a result of repetitive learning
What studies to use for neural pruning
Luby
What studies to use for neural network
Maguire
