Exam 1: Neural Communication Flashcards
Neurotransmitters
Chemical messengers that transmit signals between neurons at synapses.
Action potential
An electrical impulse that travels along a neuron’s axon to transmit information.
Chemical synapse
A junction between neurons where neurotransmitters are released to communicate.
Synaptic cleft
The small gap between the presynaptic and postsynaptic neurons where neurotransmitter diffusion occurs.
Presynaptic
Referring to the neuron that releases neurotransmitters at a synapse.
Presynaptic terminal
The axon terminal of a neuron where neurotransmitters are stored and released.
Postsynaptic
Referring to the neuron that receives signals at a synapse.
Postsynaptic terminal
The region on the receiving neuron where neurotransmitter receptors are located.
Excitatory Post-Synaptic Potential (EPSP)
A temporary increase in membrane potential that brings a neuron closer to firing an action potential.
Inhibitory Post-Synaptic Potential (IPSP)
A temporary decrease in membrane potential that makes a neuron less likely to fire an action potential.
Electrical synapse
A type of synapse where ions pass directly between neurons through gap junctions, allowing rapid communication.
Connexon
A protein channel that forms a gap junction, enabling direct electrical communication between neurons.
Resting potential
The stable negative charge maintained by a neuron when it is not actively firing.
Threshold
The membrane potential level at which a neuron fires an action potential.
Neural circuit
A network of interconnected neurons that process and transmit information.
Feedback
A process in which neurons influence their own inputs, allowing dynamic modulation of activity.
Parallel processing
The simultaneous processing of different aspects of information along multiple neural pathways.
Computational neuroscience
A field that develops mathematical and computer models to simulate neural networks.
Interneuron
A neuron that connects other neurons within a circuit, often involved in processing and modulation.
Excitatory neuron
A neuron that increases the likelihood of firing in its target neurons.
Inhibitory neuron
A neuron that decreases the likelihood of firing in its target neurons.
Central pattern generator (CPG)
A neural network capable of producing rhythmic motor patterns, like walking or swimming.
Plasticity
The ability of neural circuits to adapt and reorganize in response to experience or damage.
Ion pumps
Proteins that use energy to actively transport ions across the cell membrane, maintaining concentration gradients.
Ion channels
Proteins that allow specific ions to pass through the cell membrane, enabling electrical signaling in neurons.
Electrostatic force
The force that causes opposite charges to attract and like charges to repel, influencing ion movement.
Ion
A charged particle that plays a role in neuronal signaling.
Membrane potential
The electrical charge difference across a neuron’s membrane, essential for neural signaling.
Diffusion
The movement of molecules from an area of higher concentration to lower concentration, affecting ion distribution in neurons.
Concentration gradient
The difference in ion concentration across a membrane, driving diffusion.
Ligand-gated ion channel
A channel that opens in response to the binding of a specific neurotransmitter.
Voltage-gated ion channel
A channel that opens or closes in response to changes in membrane potential.
Equilibrium potential
The membrane potential at which the electrostatic and diffusion forces acting on an ion are balanced.
Resting potential
The stable negative charge maintained by a neuron when it is not actively firing.
Rising phase
The part of the action potential where sodium ions enter the neuron, making it more positive.
Falling phase
The part of the action potential where potassium ions exit the neuron, making it more negative.
Undershoot
The phase following an action potential where the membrane potential temporarily becomes more negative than the resting potential.
Refractory period
The period after an action potential when a neuron is less likely or unable to fire another action potential.
Saltatory conduction
A faster mode of action potential propagation in myelinated neurons, where signals jump between nodes of Ranvier.
Myelin sheath
A fatty layer that insulates axons, speeding up action potential conduction.
Nodes of Ranvier
Gaps in the myelin sheath where action potentials are regenerated.
Neurotransmitter release
The process by which synaptic vesicles release neurotransmitters into the synaptic cleft.
Synaptic vesicle
A small membrane-bound sac that stores neurotransmitters in the presynaptic neuron.
Exocytosis
The process by which neurotransmitters are released into the synaptic cleft via vesicle fusion with the membrane.
Neurotransmitter reuptake
The process of neurotransmitter molecules being taken back into the presynaptic neuron for reuse.
Leak channels
Ion channels that are always open, allowing passive movement of ions to help maintain resting potential.
Depolarization
A decrease in membrane potential (more positive), moving the neuron closer to firing an action potential.
Hyperpolarization
An increase in membrane potential (more negative), making it less likely for the neuron to fire an action potential.
Temporal summation
The process by which multiple excitatory inputs from the same neuron accumulate over time to bring the neuron to threshold.
Spatial summation
The process by which excitatory inputs from multiple neurons combine to bring the neuron to threshold.
Synaptic transmission
The process by which neurotransmitters are released from a presynaptic neuron and bind to receptors on a postsynaptic neuron.
Receptor
A protein structure on a neuron that binds neurotransmitters and triggers cellular responses.
Ligand
A molecule that binds to a receptor, including neurotransmitters, hormones, and drugs.
Ionotropic receptor
A receptor that directly controls ion channel opening in response to neurotransmitter binding, leading to fast synaptic transmission.
Metabotropic receptor
A receptor that, when activated, triggers intracellular signaling cascades, leading to slower but longer-lasting effects.
Excitatory neurotransmitter
A neurotransmitter that increases the likelihood that the receiving neuron will generate an action potential.
Inhibitory neurotransmitter
A neurotransmitter that decreases the likelihood that the receiving neuron will generate an action potential.
Glutamate
The primary excitatory neurotransmitter in the central nervous system.
GABA (Gamma-Aminobutyric Acid)
The primary inhibitory neurotransmitter in the central nervous system.
Dopamine
A neurotransmitter involved in reward, motivation, and motor control.
Serotonin
A neurotransmitter that regulates mood, appetite, and sleep.
Acetylcholine
A neurotransmitter involved in muscle activation, learning, and memory.
Norepinephrine
A neurotransmitter involved in arousal, attention, and the stress response.
Neuropeptides
Small protein-like molecules used by neurons for signaling, often involved in pain modulation and hormonal regulation.
Reuptake
The process of neurotransmitters being absorbed back into the presynaptic neuron after synaptic transmission.
Enzymatic degradation
The breakdown of neurotransmitters in the synaptic cleft by enzymes to terminate signaling.
Autoreceptor
A receptor located on the presynaptic neuron that regulates neurotransmitter release.
Second messenger
A molecule that relays signals from a neurotransmitter-bound receptor to intracellular targets, common in metabotropic signaling.
Amino acid neurotransmitters
Neurotransmitters that are derived from amino acids and play key roles in synaptic communication.
Glycine
An inhibitory neurotransmitter in the spinal cord and brainstem that regulates motor control.
Aspartate
An excitatory neurotransmitter in the central nervous system, though less prominent than glutamate.
Excitotoxicity
Neuronal damage caused by excessive glutamate release, leading to overstimulation and cell death.
Reuptake transporters
Proteins that remove neurotransmitters from the synaptic cleft, regulating their levels and activity.
Lipid-based neurotransmitters
Neurotransmitters derived from fats that influence neural signaling.
Endocannabinoids
A class of lipid neurotransmitters involved in modulating pain, mood, and memory.
Anandamide (AEA)
An endocannabinoid neurotransmitter that binds to cannabinoid receptors and regulates mood, pain, and appetite.
CB1 receptor
A cannabinoid receptor found primarily in the central nervous system, involved in pain regulation, mood, and memory.
CB2 receptor
A cannabinoid receptor found mainly in the immune system, playing a role in inflammation and immune response.
Retrograde signaling
A form of neural communication where neurotransmitters travel from the postsynaptic neuron to the presynaptic neuron.
Prostaglandins
Lipid molecules involved in inflammation, pain signaling, and neural function.
