excitatory synapse

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excitatory synapse

A synapse which, on activation, increases the likelihood of an action potential on the post-synaptic neuron or increases the frequency of firing of the post-synaptic neuron.


the junction between the processes of two neurons or between a neuron and an effector organ, where neural impulses are transmitted by chemical means. The impulse causes the release of a neurotransmitter (e.g. acetylcholine or norepinephrine) from the presynaptic membrane of the axon terminal. The neurotransmitter molecules diffuse across the synaptic cleft, bind with specific receptors on the postsynaptic membrane, causing depolarization or hyperpolarization of the postsynaptic cell. See also neuron.

adrenergic synapse
the neurotransmitter is norepinephrine. See also adrenergic (1).
axoaxonic synapse
axodendritic synapse
axodendrosomatic synapse
one between the axon of one neuron and the dendrites and body of another.
axosomatic synapse
cholinergic synapse
the neurotransmitter is acetylcholine. See also cholinergic.
dendrodendritic synapse
one from a dendrite of one cell to a dendrite of another.
excitatory synapse
a synapse in which the transmission of impulses is electrical not chemical. Found only in fish and invertebrates.
inhibitory synapse
hyperpolarizing electrical current is used to raise the threshold for the stimulation of a discharge of an impulse from the particular kind of nerve cell, found only in fish.
References in periodicals archive ?
At excitatory synapses, AP generation in postsynaptic neurons and ensuing propagation in neuronal circuitry is determined primarily by the EPsC amplitude, representing synaptic strength,
After initial establishment, excitatory synapses become strengthened on both the pre-and postsynaptic sides, influenced in part by activity (De Simoni et al.
This condition results when, as a result of injury, there is abnormal activity at excitatory synapses, which essentially stimulate the nerve cells to death.
Various forms of eCB-STD/LTD have been reported to occur at inhibitory and excitatory synapses in various regions of the brain.
We think that early maturation of these excitatory synapses disrupts the timing of later developmental milestones.
Think of the excitatory synapses as a road network, with traffic being guided from A to B, and the inhibitory synapses as the matrix signs that regulate the traffic," explained research leader Christiaan Levelt.
At birth, the brain is loaded with excitatory synapses which help make nerve cells 'fire,'" says Anderson, who is also an Assistant Professor of Neurology and Pathology at Harvard Medical School.