Heterosynaptic
Encyclopedia
Heterosynaptic phenomena are events that occur at the junctions (synapses) that form connections between neuron
s. A heterosynaptic phenomenon is one that involves interactions between separate synapses or groups of synapses. This term is often used in relation to long-term depression
and long-term potentiation
of neuronal firing. For example, heterosynaptic long-term depression occurs when neural activity involving one of a neuron's synapses causes the strength (the ability to transduce input) of another of the neuron's synapses to decrease.
Experimentally, Fitzsimonds et al. found in cultured hippocampal neurons that the induction of LTD is also accompanied by back propagation of depression in the dendrite tree of the presynaptic neuron. Further, depression also propagates laterally in the pre- and postsynaptic neuron. Similar results hold for the propagation of LTP. For a review of experimental results see Bi et al. Emmert-Streib introduced a learning rule for neural networks based on heterosynaptic plasticity.
Neuron
A neuron is an electrically excitable cell that processes and transmits information by electrical and chemical signaling. Chemical signaling occurs via synapses, specialized connections with other cells. Neurons connect to each other to form networks. Neurons are the core components of the nervous...
s. A heterosynaptic phenomenon is one that involves interactions between separate synapses or groups of synapses. This term is often used in relation to long-term depression
Long-term depression
Long-term depression , in neurophysiology, is an activity-dependent reduction in the efficacy of neuronal synapses lasting hours or longer. LTD occurs in many areas of the CNS with varying mechanisms depending upon brain region and developmental progress...
and long-term potentiation
Long-term potentiation
In neuroscience, long-term potentiation is a long-lasting enhancement in signal transmission between two neurons that results from stimulating them synchronously. It is one of several phenomena underlying synaptic plasticity, the ability of chemical synapses to change their strength...
of neuronal firing. For example, heterosynaptic long-term depression occurs when neural activity involving one of a neuron's synapses causes the strength (the ability to transduce input) of another of the neuron's synapses to decrease.
Experimentally, Fitzsimonds et al. found in cultured hippocampal neurons that the induction of LTD is also accompanied by back propagation of depression in the dendrite tree of the presynaptic neuron. Further, depression also propagates laterally in the pre- and postsynaptic neuron. Similar results hold for the propagation of LTP. For a review of experimental results see Bi et al. Emmert-Streib introduced a learning rule for neural networks based on heterosynaptic plasticity.