Neurons, Synapses, and Brain Development

Vocabulary flashcards covering core neuroscience terms—cells, structures, chemicals, and developmental processes—introduced in the lecture.

Neuron

Basic building block of the brain; a nerve cell that sends and receives information.

Synapse

Microscopic gap between neurons where chemical communication occurs.

Dendrite

Branch-like extensions of a neuron that receive incoming signals from other neurons.

Axon

Long fiber of a neuron that carries electrical impulses away from the cell body.

Action Potential

All-or-none electrical impulse that travels down an axon to trigger neurotransmitter release.

Electrochemical Process

Interaction of electrical signals and chemical neurotransmitters that underlies brain activity.

Excitatory Influence

Neurotransmitter effect that increases the likelihood a neuron will fire.

Inhibitory Influence

Neurotransmitter effect that decreases the likelihood a neuron will fire.

Presynaptic Neuron

Neuron that releases neurotransmitters into a synapse.

Postsynaptic Neuron

Neuron that receives neurotransmitters at the synapse.

Neurotransmitter

Chemical messenger released by neurons to transmit signals across a synapse.

Reuptake

Process by which leftover neurotransmitter is reabsorbed into the presynaptic neuron.

SSRI (Selective Serotonin Reuptake Inhibitor)

Drug class that blocks serotonin reuptake to increase mood-related neural firing.

Dopamine

Neurotransmitter involved in movement, reward, and L-DOPA therapy for Parkinson’s.

Serotonin

Neurotransmitter heavily involved in mood regulation.

L-DOPA

Precursor drug that boosts dopamine levels to treat Parkinson’s disease.

Myelin

Fatty sheath around axons that speeds neural transmission; formed by Schwann cells.

Schwann Cell

Type of glial cell that produces myelin around peripheral axons.

Glial Cell

Support cell in the nervous system, distinct from neurons.

Connectome

Complete map of neural connections within the brain.

Neurogenesis

Formation of new neurons, peaking in the third trimester before birth.

Synaptogenesis

Creation of new synapses, most active from birth to age two.

Pruning

Elimination of unused synapses to make brain networks more efficient.

Neuroplasticity

Brain’s ability to change its structure and function with experience.

Wiring by Firing

Principle that neurons that fire together become physically connected.

Dendritic Arborization

Growth and branching of dendrites to form new synaptic contacts.

All-or-None Principle

Rule that a neuron either fires at full strength or not at all.

Synaptic Cleft

Another term for the synapse or synaptic gap.

ACES (Adverse Childhood Experiences)

Measure of early life stressors linked to later mental and physical health outcomes.

Hard Problem of Consciousness

Philosophical question of how electrochemical activity produces subjective experience.