Synaptic tagging: homeostatic plasticity goes Hebbian

Abstract

Distinct plasticity mechanisms enable neurons to effectively process information also when facing global perturbations in network activity. In this issue of The EMBO Journal, Dubes et al (2022) provide a molecular mechanism whereby individual synapses during periods of chronic inactivity are "tagged" for future strengthening. These results lend further support to the idea that local, nonmultiplicative mechanisms play an important role in homeostatic synaptic plasticity as has been demonstrated for Hebbian-like synaptic plasticity.

Synaptic scaling of corticostriatal circuits underlies hyperactivity in GABA Transporter-1 deficient mice

“… 4 , 5 , 6 , 7 Synaptic scaling provides such a type of homeostasis by adjusting the strength of synapses globally or specifically upward or downward to stabilize the firing of a neuron. 8 , 9 , 10 This form of homeostatic synaptic plasticity is thought to be crucial for processes ranging from learning and memory 11 , 12 to activity-dependent development. 13 , 14 Pathologically, homeostatic plasticity has been hypothesized to be involved in a variety of neuropsychiatric disorders with excitation-inhibition (E-I) imbalance, but the mechanisms remain not well understood.…”