Neuroscience Chapter on Synaptic Transmission

The time it takes for a neurotransmitter to be released, travel across the synaptic cleft, and bind to receptors on the post-synaptic neuron.

A specialized junction where communication occurs between neurons or between a neuron and another type of cell.

A synapse where neurons are directly connected by gap junctions, allowing for rapid communication.

A synapse where neurons communicate using neurotransmitters released from the pre-synaptic neuron.

The process of removing a neurotransmitter from the synaptic cleft, ending its effect on the post-synaptic neuron.

Calcium ions (Ca2+) enter the axon terminal of a presynaptic neuron, causing synaptic vesicles to release neurotransmitters. This release occurs due to a calcium-sensing protein (synaptotagmin) interacting with SNARE proteins, leading to membrane fusion.

Neurotransmitters, released from the presynaptic neuron, diffuse across the synaptic cleft and bind to specific receptors on the postsynaptic membrane.

The binding of a neurotransmitter to its receptor on the postsynaptic membrane opens ion channels, causing a change in the membrane potential of the postsynaptic cell. This change, known as a graded potential, can be either excitatory or inhibitory.

The frequency of nerve impulses affects the amount of neurotransmitter released. A higher impulse frequency leads to the release of more neurotransmitter.

SNARE proteins are key players in neurotransmitter release. They facilitate the fusion of synaptic vesicles with the presynaptic membrane, allowing neurotransmitters to be released into the synaptic cleft.

Junctions that enable information transfer between neurons, or between a neuron and an effector cell.

Gap junctions connect the cytoplasm of adjacent neurons allowing electrical signals to flow directly between them, characterized by rapid transmission.

1. Action potential arrives at the axon terminal.
2. Calcium ions enter the axon terminal, triggering the release of neurotransmitter from synaptic vesicles.
3. Neurotransmitter diffuses across the synaptic cleft and binds to receptors on the postsynaptic neuron.
4. Binding of neurotransmitter opens ion channels, leading to postsynaptic potential changes.
5. Neurotransmitter is removed from the synaptic cleft by reuptake, enzymatic degradation, or diffusion.

Changes in membrane potential of the postsynaptic neuron, caused by the binding of neurotransmitters to their receptors.

The process of integrating multiple postsynaptic potentials at a neuron, determining whether it will reach threshold and fire an action potential.

The summing of postsynaptic potentials to determine the overall effect on the neuron.

Spatial summation occurs when multiple presynaptic neurons release neurotransmitter onto the same postsynaptic neuron, adding their potentials together. Temporal summation occurs when a single presynaptic neuron releases neurotransmitter repeatedly, with potentials adding up over time.

Chemical messengers released by neurons to communicate with other cells. They are categorized by their effects (excitatory or inhibitory) and actions (direct or indirect) ,and interact with specific receptors.

Ionotropic receptors have direct channels that open or close in response to neurotransmitter binding, causing rapid effects. Metabotropic receptors activate G proteins causing indirect effects through second messengers.

The process by which neurons integrate information from multiple sources through summation, modulation, and other interactions.

A type of postsynaptic potential that causes a local depolarization in the postsynaptic neuron, making it more likely to fire an action potential.

A type of postsynaptic potential that causes a local hyperpolarization in the postsynaptic neuron, making it less likely to fire an action potential.

The process of adding together multiple postsynaptic potentials at the same time, either from the same synapse or from different synapses.

Summation of postsynaptic potentials that occur when a single synapse is repeatedly stimulated in rapid succession, before the previous potential dissipates.

Summation of postsynaptic potentials that occur when multiple synapses are stimulated simultaneously.

The process of strengthening a synapse by repeatedly using it, making it more likely to elicit a response in the postsynaptic neuron.

A long-lasting form of synaptic potentiation, often associated with learning and memory.

The process of inhibiting the release of neurotransmitter from a presynaptic neuron by another neuron, through an axoaxonal synapse.

A chemical messenger released from a presynaptic neuron to communicate with a postsynaptic neuron.

A classification of neurotransmitters based on their effects on the postsynaptic neuron, either excitatory (depolarizing) or inhibitory (hyperpolarizing).

A type of neurotransmitter that decreases the likelihood of a neuron firing an action potential, making it less likely to send a signal. It is a 'brake' for the nervous system.

A type of neurotransmitter that increases the likelihood of a neuron firing an action potential, making it more likely to send a signal. It serves as a 'gas pedal' for the nervous system.

A neurotransmitter that directly binds to and opens ion channels on the postsynaptic neuron, causing a rapid change in membrane potential. This results in quick and short-lasting effects.

A neurotransmitter that acts through intracellular second messengers, usually G protein pathways, resulting in broader and longer-lasting effects similar to hormones.

A type of receptor that acts as a ligand-gated ion channel, opening when a neurotransmitter binds to it. This causes a rapid and brief change in membrane potential.

A type of receptor that acts through G-protein pathways, leading to indirect, complex, slow, and often prolonged effects. It involves a series of steps and uses second messengers.

The process of neurons working together in groups to achieve complex neural functions. This involves billions of neurons in the central nervous system, allowing for smooth operation.

A pattern of neural processing where information travels along a single pathway from one point to another. It produces predictable and consistent responses.