A synaptic potential exists at the INPUT of a neuron (dendrite), and an action potential occurs at the OUTPUT of a neuron (axon). (from OldGuy)
(from Ilantoren:) A synaptic potential is the result of many excitatory post synaptic potentials (epsp) each one caused by the synaptic vesicles released by the pre-synaptic terminus. If there are enough of these epsp then the responses will summate and depolarize the post-synaptic membrane at the axon hillock enough to fire an action potential.
The presynaptic cell that must have action potentials to produce one or more action potentials in the postsynaptic cell is the neuron releasing neurotransmitters at the synapse. When an action potential reaches the presynaptic terminal, it triggers the release of neurotransmitters into the synaptic cleft, which then bind to receptors on the postsynaptic cell membrane, leading to the generation of an action potential in the postsynaptic cell.
Depolarization at the motor end plate upon arrival of action potentials triggers the release of neurotransmitter acetylcholine into the synaptic cleft. This acetylcholine then binds to receptors on the muscle cell membrane, initiating muscle contraction by depolarizing the muscle cell membrane and allowing the action potential to propagate along the muscle fiber.
Local Potentials: Ligand regulated, may be depolarizing or hyperpolarizing, reversible, local, decremental Action Potentials: Voltage regulated, begins with depolarization, irreversible, self-propagating, nondecremental.
The resting and action potentials depend on the balance of charges of the area outside the neuron and inside the neuron. A resting potential is when the neuron is more negatively (approximately -70mv) charged than the area outside the neuron. The action potential occurs when sodium ions rush into the neuron, causing the polarity to be reversed. When there is no difference in charge between the area inside the neuron and the area outside the neuron, no action potentials can be started by that neuron.
The time between action potentials is known as the refractory period, during which the neuron cannot generate another action potential. This period is essential to ensure that action potentials travel in one direction and allows the neuron to recover before firing again. The refractory period can vary but generally lasts around 1-2 milliseconds.
a periodic production of action potentials even without synaptic input
In general, action potentials that reach the synaptic knobs cause a neurotransmitter to be released into the synaptic cleft. The arrival of the action potential opens voltage-sensitive calcium channels in the presynaptic membrane.
Local graded potentials are small changes in membrane potential that occur in response to neurotransmitter binding to ligand-gated ion channels on the post-synaptic neuron. These potentials can summate and affect the likelihood that an action potential will be generated in the neuron. They are also referred to as synaptic potentials.
The presynaptic cell that must have action potentials to produce one or more action potentials in the postsynaptic cell is the neuron releasing neurotransmitters at the synapse. When an action potential reaches the presynaptic terminal, it triggers the release of neurotransmitters into the synaptic cleft, which then bind to receptors on the postsynaptic cell membrane, leading to the generation of an action potential in the postsynaptic cell.
Depolarization at the motor end plate upon arrival of action potentials triggers the release of neurotransmitter acetylcholine into the synaptic cleft. This acetylcholine then binds to receptors on the muscle cell membrane, initiating muscle contraction by depolarizing the muscle cell membrane and allowing the action potential to propagate along the muscle fiber.
Synapses occur between two neurons. Electrical activitiy in the pre-synaptic neuron influences the post-synaptic neuron. There are two types of synapses in the body: Electrical and chemical. Electrical synapses occur in pre and post synaptic neurons that are joined via gap junctions. Currents from action potentials flow across the junction through channels called connexons. This current will depolarize the membrane of the post synaptic neuron to threshold, which will continue the action potential in the cell. Electrical synapses are fast and bidirectional. However, they are mainly found in cardiac and smooth muscles, and not in the mammalian nervous system.Chemical synapses use neurotransmitters. Depolarization occurs in the pre-synaptic neuron and calcium ions rush in. The calcium ions activate neurotransmitter release into the synaptic cleft. The neurotransmitters reach the post-synaptic neuron and cause action potentials to develop.Note: this can go into much more detail
Local Potentials: Ligand regulated, may be depolarizing or hyperpolarizing, reversible, local, decremental Action Potentials: Voltage regulated, begins with depolarization, irreversible, self-propagating, nondecremental.
neurotransmitters. These neurotransmitters are released into the synaptic cleft to relay signals to the next neuron in the communication pathway.
Graded potentials are small changes in membrane potential that can vary in size and duration, while action potentials are brief, large changes in membrane potential that are all-or-nothing. Graded potentials are used for short-distance communication within a neuron, while action potentials are used for long-distance communication between neurons.
John H. Byrne has written: 'An introduction to membrane transport and bioelectricity' -- subject(s): Action potentials (Electrophysiology), Biological transport, Cell Membrane, Electrophysiology, Membrane Potentials, Physiology, Synaptic Transmission 'Learning and Memory'
The inter-spike interval is the time between consecutive action potentials. The frequency of action potentials is inversely related to the inter-spike interval, meaning shorter inter-spike intervals result in higher action potential frequencies. This relationship is crucial in determining the rate of neuronal firing.
The resting and action potentials depend on the balance of charges of the area outside the neuron and inside the neuron. A resting potential is when the neuron is more negatively (approximately -70mv) charged than the area outside the neuron. The action potential occurs when sodium ions rush into the neuron, causing the polarity to be reversed. When there is no difference in charge between the area inside the neuron and the area outside the neuron, no action potentials can be started by that neuron.