Metaplasticity governs natural experience-driven plasticity of nascent embryonic brain circuits.

TitleMetaplasticity governs natural experience-driven plasticity of nascent embryonic brain circuits.
Publication TypeJournal Article
Year of Publication2009
AuthorsDunfield D, Haas K
Date Published2009 Oct 29
Keywords2-Amino-5-phosphonovalerate, Action Potentials, Animals, Behavior, Animal, Biophysics, Brain, Calcium, Electric Stimulation, Excitatory Amino Acid Antagonists, Long-Term Potentiation, Models, Neurological, Nerve Net, Neurons, Photic Stimulation, Statistics as Topic, Superior Colliculi, Synapses, Visual Pathways, Xenopus laevis

During embryogenesis, brain neurons receiving the same sensory input may undergo potentiation or depression. While the origin of variable plasticity in vivo is unknown, it plays a key role in shaping dynamic neural circuit refinement. Here, we investigate effects of natural visual stimuli on neuronal firing within the intact, awake, developing brain using calcium imaging of 100 s of central neurons in the Xenopus retinotectal system. We find that specific patterns of visual stimuli shift population responses toward either potentiation or depression in an N-methyl-D-aspartate receptor (NMDA-R)-dependent manner. In agreement with Bienenstock-Cooper-Munro metaplasticity, our results show that functional potentiation or depression can be predicted by individual neurons' specific receptive field properties and historic firing rates. Interestingly, this activity-dependent metaplasticity is itself NMDA-R dependent. Furthermore, network analysis reveals increased correlated firing of neurons that undergo potentiation. These findings implicate metaplasticity as a natural property regulating experience-dependent refinement of nascent embryonic brain circuits.

Alternate JournalNeuron
PubMed ID19874791
Grant List / / Canadian Institutes of Health Research / Canada