Functional clustering drives encoding improvement in a developing brain network during awake visual learning.

TitleFunctional clustering drives encoding improvement in a developing brain network during awake visual learning.
Publication TypeJournal Article
Year of Publication2012
AuthorsPodgorski K, Dunfield D, Haas K
JournalPLoS Biol
Date Published2012 Jan
KeywordsAnimals, Artifacts, Brain, Calcium, Calcium Signaling, Cluster Analysis, Environmental Monitoring, Functional Neuroimaging, Larva, Learning, Models, Biological, Neural Pathways, Neuronal Plasticity, Optics and Photonics, Pattern Recognition, Visual, Photic Stimulation, Wakefulness, Xenopus laevis

Sensory experience drives dramatic structural and functional plasticity in developing neurons. However, for single-neuron plasticity to optimally improve whole-network encoding of sensory information, changes must be coordinated between neurons to ensure a full range of stimuli is efficiently represented. Using two-photon calcium imaging to monitor evoked activity in over 100 neurons simultaneously, we investigate network-level changes in the developing Xenopus laevis tectum during visual training with motion stimuli. Training causes stimulus-specific changes in neuronal responses and interactions, resulting in improved population encoding. This plasticity is spatially structured, increasing tuning curve similarity and interactions among nearby neurons, and decreasing interactions among distant neurons. Training does not improve encoding by single clusters of similarly responding neurons, but improves encoding across clusters, indicating coordinated plasticity across the network. NMDA receptor blockade prevents coordinated plasticity, reduces clustering, and abolishes whole-network encoding improvement. We conclude that NMDA receptors support experience-dependent network self-organization, allowing efficient population coding of a diverse range of stimuli.

Alternate JournalPLoS Biol.
PubMed ID22253571
PubMed Central IDPMC3254648
Grant List / / Canadian Institutes of Health Research / Canada