Neuroscience Quiz: MRI and Spinal Cord Functions

The brain and spinal cord; the control center of the body.

Nerves outside the CNS; connects the CNS to the rest of the body.

Star-shaped glial cells that support neurons structurally and metabolically. Form the Blood-Brain Barrier.

A barrier created by astrocytes that regulates the passage of substances from the blood into the brain tissue.

Area of the CNS containing densely packed neuron cell bodies.

Area of the CNS containing myelinated axons.

Fluid filling the ventricles of the brain and the spinal cord; cushions the CNS.

Protective membranes surrounding the brain and spinal cord, including dura mater, arachnoid mater, and pia mater.

Outer layer of the cerebrum; responsible for higher-level functions like decision-making.

Part of the brain involved in coordinating motor activity.

Brain region controlling homeostasis and basic drives

Cell that transmits nerve impulses.

Glial cells that produce myelin in the CNS.

Brain region controlling language production.

Brain region responsible for understanding language.

Connects the brain to the body, enabling information transmission and reflex actions.

Spinal nerves emerge from the spinal cord in different regions (cervical, thoracic, lumbar, sacral, coccygeal), relating to the vertebrae they exit from.

Nerve pathways in the spinal cord that carry information up (to the brain) and down (from the brain).

Afferent fibers carry sensory information to the spinal cord, while efferent fibers carry motor commands from the spinal cord.

A nerve is a bundle of axons, while a neuron is a single nerve cell. Nerves are bundles of axons that follow a path; neurons are individual cells and are part of the nerve.

The voltage difference across a cell membrane, usually negative in neurons due to excess anions inside and cations outside.

The stable, negative voltage difference across the neuronal membrane when the neuron is not actively transmitting signals. Around -70mV.

The Na+/K+ pump actively transports sodium ions out of the cell and potassium ions in, while leaky potassium channels allow some potassium to leak out, creating the negative charge inside.

A reduction in the membrane potential, making it more positive, due to an influx of positive ions (usually Na+).

An increase in the membrane potential, making it more negative, due to an efflux of positive ions (usually K+) or influx of negative ions.

A localized, temporary change in membrane potential, can be depolarizing or hyperpolarizing. The magnitude varies with the strength of the stimulus.

A rapid, short-lasting, all-or-none electrical signal that travels along the axon of a neuron. Propagated by the opening and closing of voltage-gated Na+ and K+ channels.

The minimum membrane potential change required to trigger an action potential, typically around -55mV.

A graded potential that reaches the threshold potential triggers the opening of voltage-gated Na+ channels, allowing Na+ influx and rapid depolarization. This positive feedback further opens more Na+ channels, creating a self-propagating wave of depolarization.

The return of the membrane potential to its resting state after an action potential, due to the closing of Na+ channels and the opening of K+ channels.

The time period after an action potential when a new action potential cannot be generated. Divided into absolute refractory and relative refractory periods.

The spread of action potential along the axon of a non-myelinated neuron, involving the sequential activation of adjacent membrane patches.

The rapid propagation of action potential along myelinated axons, where the signal jumps from one node of Ranvier to the next. Faster than contiguous conduction.

A potent neurotoxin that blocks voltage-gated Na+ channels, preventing action potential generation. Found in pufferfish and other animals.

Myelin acts as an insulator, preventing the leakage of current and concentrating ion channels at the nodes of Ranvier. This allows for faster saltatory conduction, where the signal jumps between nodes.

Gaps in the myelin sheath along an axon, where action potentials are generated.

A rapid electrical signal that travels along an axon, transmitting information in the nervous system.

A change in membrane potential that can vary in size and duration, depending on the strength of the stimulus.

An autoimmune condition where the body's immune system attacks the myelin sheath of axons, affecting nerve impulse transmission.

The long, slender projection of a neuron that conducts nerve impulses away from the cell body.

Branched projections of a neuron that receive signals from other neurons.

The junction between two neurons, where nerve impulses are transmitted from one neuron to another.

A chemical messenger released by a neuron that transmits signals across a synapse.

The process of transmitting a signal from one neuron to another across a synapse.

Multiple EPSPs from a single presynaptic neuron firing in rapid succession. This leads to an increased likelihood of the postsynaptic neuron firing.

Multiple EPSPs arriving simultaneously from different presynaptic neurons. This allows the postsynaptic neuron to reach threshold and fire.

Inhibitory postsynaptic potentials (IPSPs) can counteract excitatory postsynaptic potentials (EPSPs) resulting in a decrease in the likelihood of the postsynaptic neuron firing

A single presynaptic neuron branches out to affect many postsynaptic neurons, spreading information widely.

Many presynaptic neurons converge onto a single postsynaptic neuron, integrating several inputs.

The frequency of action potentials determines the strength of stimulus. A higher frequency of action potentials indicates a stronger stimulus.

The process of transferring a short-term memory into a long-term memory.

Repetitive stimulation of a synapse strengthens that synaptic connection over time. This is a major mechanism for learning and memory.