Prescient Synapses: Gating Future Neuronal Consciousness Through Synaptic Tagging and Metaplasticity

  • Steven A. Connor
  • Peter V. NguyenEmail author


Restriction of synaptic plasticity to time frames dictated by fast synaptic transmission would yield neuronal networks incapable of encoding qualitatively rich memories. The ability to associate and encode temporally disparate aspects of a memory confers significant survival advantages. The temporal spread of everyday experiences necessitates broad time windows for synaptic encoding of multiple related events. By extending the time frame in which events can be associated at a synaptic level, and biasing synapses towards a plasticity-conducive state, synaptic tagging and metaplasticity provide potent mechanisms for enhancing memory quality in the brain. Tagging and metaplasticity serve as gateways for augmenting neuronal consciousness. Priming of future synaptic plasticity can enhance neuronal detection, encoding, and association of salient future events, and it can facilitate storage of detailed memories. We review key intracellular signalling mechanisms that initiate lasting changes in the ability of synapses to undergo metaplasticity, along with leading candidate synaptic tags that facilitate metaplasticity. We also speculate on how these phenomena bolster neuronal consciousness to sculpt the brain’s capacity to dynamically encode and store information.


Synaptic tagging Metaplasticity Protein kinases and phosphatases Memory Cellular consciousness 


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© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Centre for NeuroscienceUniversity of Alberta School of MedicineEdmontonCanada
  2. 2.Department of PhysiologyUniversity of Alberta School of MedicineEdmontonCanada
  3. 3.Department of PsychiatryUniversity of Alberta School of MedicineEdmontonCanada

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