Spatial summation

Definition

Spatial summation is a mechanism in the nervous system where multiple presynaptic neurons release neurotransmitters at various synapses with a single postsynaptic neuron, leading to a stronger cumulative effect. This process can facilitate or inhibit the postsynaptic neuron from reaching the threshold needed to fire an action potential.

Related terms

Action Potential: A rapid rise and subsequent fall in voltage or electrical charge across a cellular membrane, primarily found in neurons, that occurs when a neuron sends information down an axon.

Synapse: The junction between two neurons or between a neuron and muscle cell where exchange of chemical signals or electrical activity leads to transmission of impulses.

Neurotransmitter: A chemical substance released at the end of a nerve fiber by the arrival of a nerve impulse and by diffusing across the synapse or junction, causes the transfer of the impulse to another nerve fiber, a muscle fiber, or some other structure