Neuroplasticity Lecture Vocabulary

Flashcards covering essential vocabulary from the lecture on neuroplasticity, synaptic mechanisms, learning, and related brain changes.

Neuroplasticity

The brain’s ability to physically and chemically change its structure and function in response to experience.

Dendrite

Branch-like extensions of a neuron that receive signals from other neurons; can grow or retract during plasticity.

Axon

Long fiber that carries an action potential away from the neuron’s soma toward other cells.

Synapse

The microscopic gap between neurons where neurotransmitters are released to pass signals.

Presynaptic Neuron

The neuron that releases neurotransmitter into the synapse.

Postsynaptic Neuron

The neuron that receives neurotransmitter and shows plastic changes (e.g., new receptors).

Action Potential

An electrical impulse that travels down the axon; always the same size—either fires or not.

All-or-None Principle

Rule stating an action potential is either triggered fully or not at all; strength is coded by firing rate, not size.

AMPA Receptor

Postsynaptic receptor that produces a one-to-one response to glutamate; numbers increase during learning.

NMDA (NR) Receptor

Postsynaptic receptor that activates only with strong glutamate input and triggers creation of new AMPA receptors.

Long-Term Potentiation (LTP)

Lasting increase in synaptic strength produced by high activity; core cellular mechanism of learning and memory.

Synaptogenesis

Formation of new synapses and dendritic branches between neurons.

Neurogenesis

Birth of new neurons, peaking in the last prenatal trimester.

Experience-Dependent Plasticity

Brain changes that arise from unique individual experiences; requires environmental input.

Experience-Expectant Plasticity

Developmental wiring laid down in anticipation of universal experiences (e.g., basic sensory input).

“Neurons that fire together wire together”

Phrase summarizing Hebb’s principle that repeated co-activation strengthens connections.

Dopamine

Neurotransmitter central to reward, motivation, and many addictions.

Reward Pathway

Dopaminergic circuit that signals pleasure and reinforces behaviors to be repeated.

Downregulation

Decrease in receptor number or neurotransmitter release after chronic overstimulation (e.g., drug abuse).

Structural Plasticity

Physical changes such as new dendrites and synapses forming between neurons.

Functional Plasticity

Changes in how strongly existing neural circuits communicate (e.g., via more receptors).

Synaptic Pruning

Elimination or retraction of unused synaptic connections, refining neural circuits.

Methamphetamine (Brain Effect)

Drug that causes massive dopamine release (~1000× normal), leading to receptor loss and high addiction risk.

Postsynaptic Sensitization

Enhanced responsiveness of a postsynaptic neuron due to added receptors after strong input.