NEUROSCIENCE Chapter 2: Structure and Function of the Nervous System

These flashcards cover key vocabulary and concepts from the lecture notes on neuroscience, specifically focusing on the structure and function of the nervous system.

Glial Cells

Non-neuronal support cells essential for brain health, outnumbering or equaling neurons to maintain homeostasis, form myelin, and protect the nervous system

Oligodendrocytes (Glial Cell 1/4)

• Found in the CNS

• Produce myelin for multiple axons in the brain & spinal cord

• Increase conduction speed

Schwann Cells (Glial Cell 2/4)

• Found in the PNS

• Myelinate 1 axon segment each

• Important for nerve regeneration

Astrocytes (Glial Cell 3/4)

• Star-shaped glial cells in the brain and spinal cord

• Support and maintain neurons

• Regulate blood flow

• Contribute to the blood-brain barrier

Microglia (Glial Cell 4/4)

• Immune Cells of CNS

• Remove debris & damaged tissue

Neurons

The basic building blocks of the nervous system, consisting of a soma, axons, and dendrites.

Soma (Neurons)

Cell body

Presynapic Nueronal Signaling

The process where a neuron (the sender) releases neurotransmitters from its axon terminal into the synaptic cleft to communicate with a post-synaptic cell

Postsynapic Neuronal Signaling

The process by which a neuron receives, interprets, and transduces chemical signals (neurotransmitters) from a presynaptic cell into electrical or biochemical changes

Membrane Potential

The electrical potential difference across a neuronal membrane, primarily related to sodium and potassium ion distribution.

Electrical Transmission

Electrical transmission in neurons involves the rapid propagation of action potentials—electrochemical impulses—along the axon, driven by the movement of ions across the membrane through voltage-gated ion channels. This process is essential for communication between neurons and the overall functioning of the nervous system.

Action Potential

A rapid change in membrane potential that propagates along the axon of a neuron.

All-or-None Law

A neuron or muscle fiber fires an action potential at full strength or not at all, independent of stimulus intensity

Ion pump

Protein structures in neurons that actively transport ions across the membrane, maintaining the resting membrane potential and facilitating action potentials.

Ion Channel

A protein structure that allows ions to pass through the cell membrane, crucial for neuronal signaling and communication.

Electrical Gradient

The difference in electric potential across a cell membrane created by the distribution of ions, influencing the movement of ions during action potentials.

Sodium-Potassium Pump

A membrane protein that actively transports sodium out of and potassium into neurons, maintaining the resting membrane potential.

Synaptic Transmission (Chemical & Electrical)

The process of communication between neurons, involving the release of neurotransmitters at the synapse.

Chemical Synapse (Synaptic Transmission 1/2)

• A type of synapse where neurotransmitters are released from one neuron to bind to receptors on another, facilitating slower but more versatile communication

• Neurotransmitter release

• Receptor Binding

• Excitatory or Inhibitory effects

Receptor Binding

The process by which a neurotransmitter binds to a specific receptor on a post-synaptic neuron, triggering a response.

Electrical Synapse (Synaptic Transmission 2/2)

• A type of synapse where electrical current flows directly between neurons, allowing for rapid communication

• Gap Junctions

• Very fast

• Less flexible than chemical

Gap Junction

A specialized intercellular connection formed between neurons that allows for the direct transfer of ions and small molecules, facilitating rapid communication.

Peripheral Nervous System (PNS)

The part of the nervous system that exists outside the brain and spinal cord.

Central Nervous System (CNS)

The part of the nervous system that includes the brain and spinal cord.

Autonomic Nervous System (ANS)

A division of the PNS that regulates involuntary bodily functions.

Gray Matter

Regions of the CNS that contain neuronal cell bodies and are involved in processing information.

White Matter

Areas in the CNS that consist largely of myelinated axons and are involved in transmitting signals.

Ventricles (of the brain)

A network of four communicating, fluid-filled cavities (two lateral, third, and fourth) that produce and circulate cerebrospinal fluid (CSF) to protect, nourish, and cleanse the central nervous system

Brainstem

Connects the cerebrum to the spinal cord, acting as a vital relay station and controlling essential automatic functions like breathing, heart rate, blood pressure, consciousness, and sleep, while also managing motor and sensory signals for the face, head, and body through cranial nerves. Consists of the Thalamus, Midbrain, Pons, and Medulla Oblongata.

Pons

Bridge that relays signals between the cerebrum and cerebellum

Limbic System

A complex set of brain structures (including the amygdala, hippocampus, and hypothalamus) responsible for regulating emotions, memory formation, motivation, and behaviors related to survival, such as feeding, fight-or-flight responses, and sexual behavior

Somatosensory Cortex (Located in parietal lobe)

A part of the brain responsible for processing sensory input from the body.

Frontal Cortex (Frontal Lobe)

the brain's largest region, responsible for high-level "executive" functions, voluntary movement, personality expression, and social behavior

Topographical Memory

The ability to remember and recognize the spatial layout of environments and locations.

Brodmann's Areas

Regions of the cerebral cortex defined by their cellular makeup which corresponds to different functions.

Neurogenesis (Early Development)

The process by which new neurons are formed in the brain.

Synaptogenesis (Early Development)

The formation of new synapses between neurons.

Neuronal Proliferation (Early Development)

The process of rapid cell division in the early development of the nervous system.

Neuronal Migration (Early Development)

Fundamental embryonic process where neurons move from their birth sites to their final, functional positions in the developing nervous system

Synapse Elimination (Early Development)

Excessive neurons and connections (synapses) are removed to refine neural circuits