Neuroplasticity Flashcards
(23 cards)
What is a neuron and how does it function?
A neuron is a nerve cell that receives, processes, and transmits information via electrical signals
What is neuroplasticity?
The brain’s ability to reorganise and change its structure in response to internal or external changes, such as learning, experience, or injury.
What is a neural network?
Networks formed by groups of neurons that process and transmit information. Created through repeated stimulation and experience.
What is Hebbian learning?
Based on the principle “cells that fire together, wire together.” When two neurons fire together, their connection strengthens, forming cell assemblies that can store memories.
What happens during repeated stimulation of neurons?
Leads to long-term potentiation (LTP) → gene expression → dendritic branching, increasing the number of synapses and enhancing memory.
What is dendritic branching and why is it important?
The growth of dendrites from repeated neuron firing, increasing synaptic density and forming more connections—linked to increased grey matter, crucial for learning.
What is synaptic pruning?
The elimination of unused neurons and synapses to improve brain efficiency, especially during childhood and adolescence.
What is the “use it or lose it” principle in brain development?
Frequently used connections are strengthened, while unused ones are eliminated (pruned).
How does synaptic growth change in early childhood?
At age 3, a child has ~1,000 trillion synaptic connections—twice as many as adults. Brain reaches 95% of adult weight by age 6.
What happens around age 11 in brain development?
The brain undergoes massive synaptic pruning, streamlining connections.
What was the aim of Squeglia et al. (2013)?
To examine how synaptic pruning during adolescence is linked to cognitive ability.
What type of study was Squeglia et al. (2013)?
A correlational study using MRI scans to measure brain structure and standardised tasks to assess cognitive ability.
What technology was used to study the brain in this research?
MRI (Magnetic Resonance Imaging) was used to measure cortical thickness—the amount of grey matter in the outer brain layer.
Who were the participants in Squeglia et al. (2013)?
185 healthy adolescents aged 12–14 from San Diego, USA.
How did the researchers ensure a representative and healthy sample?
Participants were excluded if they used alcohol, cigarettes, or drugs, had psychological disorders or learning disabilities and were not fluent in English
What correlation was found between age and cortical thickness?
A negative correlation—older adolescents had less cortical thickness in 10 brain areas (7 in the frontal lobe) → evidence of synaptic pruning.
Was there a correlation between cortical thickness and working memory?
No significant correlation was found between cortical thickness and working memory or attention.
Were there gender differences in cortical thinning?
Yes, boys showed more cortical thinning (synaptic pruning) than girls in the studied age group.
What did the study conclude about synaptic pruning and cognition?
Synaptic pruning, especially in the parietal and frontal lobes, may support cognitive development by eliminating unnecessary synapses and strengthening important neural networks.
How does this support the theory of neuroplasticity?
It supports the idea that the brain adapts its structure during adolescence to become more efficient for learning and thinking.
What are two strengths of Squeglia et al.’s methodology?
Use of MRI scans allowed for non-invasive, accurate measurements of brain structure, and a controlled sample (no substance use, disorders) increased internal validity..
What are two key limitations of the study?
Correlational → cannot prove cause and effect between cortical thinning and cognition
MRI scans have poor temporal resolution and are sensitive to movement, which can reduce scan quality—especially in young participants.
Why is it difficult to conclude that thinner cortices cause higher cognitive ability?
Because the study is correlational, we can’t rule out third variables or reverse causation.
