(2006a): "We investigated analytically and numerically the interplay between two opposing forms of synaptic plasticity: positive-feedback, long-term potentiation/depression (LTP/LTD), and negative-feedback, homeostatic synaptic plasticity (HSP). A detailed model of a CA1 pyramidal neuron, with numerous HSP-modifiable dendritic synapses, demonstrates that HSP may have an important role in selecting which spatial patterns of LTP/LTD are to last.
...
Despite the negative-feedback nature of HSP, under both local and global HSP, numerous synaptic
potentiations/depressions can persist. These experimentally testable results imply that HSP could be significantly involved in shaping the spatial distribution of synaptic weights in the dendrites and not just normalizing it, as is currently believed."
(2006b): "Homeostatic synaptic plasticity (HSP) is an important mechanism attributed with the slow regulation of the neuron's activity. Whenever activity is chronically enhanced, HSP weakens the weights of the synapses in the dendrites and vice versa. Because dendritic morphology and its electrical properties partition the dendritic tree into functional compartments, we set out to explore the interplay between HSP and dendritic compartmentalization.
...
The spatial distribution of synaptic weights throughout the dendrites will markedly differ under the local versus global HSP mechanisms. We suggest an experimental paradigm to unravel which type of HSP mechanism operates in the dendritic tree. The answer to this question will have important implications to our understanding of the functional organization of the neuron."
References:
1 .
Rabinowitch I, Segev I (2006) The interplay between homeostatic synaptic plasticity and functional dendritic compartments. J Neurophysiol 96:276-83 [PubMed]
2 .
Rabinowitch I, Segev I (2006) The endurance and selectivity of spatial patterns of long-term potentiation/depression in dendrites under homeostatic synaptic plasticity. J Neurosci 26:13474-84 [PubMed]
3 .
Rabinowitch I, Segev I (2008) Two opposing plasticity mechanisms pulling a single synapse. Trends Neurosci 31:377-83 [PubMed]
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