NSCI 140 - Intro to Neuroplasticity (Modules 3-4)

What is neuroplasticity?

The brain's ability to reorganize by forming, eliminating, or modifying neural connections in response to experience, learning, and injury

What three processes does neuroplasticity support?

Development, adaptation, and recovery

Who is considered the father of neuropsychology and neuronal networks?

Donald Hebb

What is Hebbian learning?

The principle that repeated co-activation strengthens connections between neurons (“fire together, wire together”)

What does "neurons that fire together wire together" mean?

Synaptic connections strengthen when neurons activate together repeatedly

What does “neurons that fire apart wire apart” mean?

Connections weaken when neurons consistently activate at different times

What is a synapse?

The connection between a presynaptic neuron and a postsynaptic neuron where communication occurs.

Which neuron sends the signal?

Presynaptic neuron

Which neuron receives the signal?

Postsynaptic neuron

What changes can occur at the synaptic level during neuroplasticity?

Neurotransmitter release, receptor number, synapse shape/size, and number of synaptic connections

What is LTP (long-term potentiation)?

Strengthening of synaptic connections following repeated stimulation

What are the three levels of neuroplasticity discussed in class?

Cellular, network, and system levels

What is neurogenesis?

The generation of new neurons

What is synaptogenesis?

The creation of new synapses

What is synaptic pruning?

Elimination of unnecessary synapses

What is myelination?

Wrapping axons with myelin to increase speed and efficiency of neural transmission

What are the three stages of typical brain-system maturation?

Growth → Peak → Pruning

During development, does the brain shift from quantity to quality, or quality to quantity?

Quantity to quality

Why is the statement "the brain develops as one homogenous unit" incorrect?

Different brain structures mature at different times

What is hierarchical development?

Brain maturation occurs bottom-up and back-to-front

When does most brain "hard wiring" occur?

From before birth through early adulthood

What are the two major waves of plasticity?

Early childhood and adolescence

A child repeatedly practices piano and the neural connections involved become stronger. Which principle explains this?

Hebbian learning ("fire together, wire together")

A neural pathway becomes faster because axons gain additional myelin. What process is occurring?

Myelination

An adolescent shows increased emotional reactivity and risk-taking. What developmental mismatch contributes to this?

The limbic system matures earlier than the prefrontal cortex

Why is high plasticity considered a "double-edged sword"?

It allows rapid learning and adaptation but can also lead to maladaptive changes if experiences or regulatory mechanisms are unfavourable