Sensory-Evoked Spiking Behavior Emerges via an Experience-Dependent Plasticity Mechanism.
The ability to generate action potentials (spikes) in response to synaptic input determines whether a neuron participates in information processing. How a developing neuron becomes an active participant in a circuit or whether this process is activity dependent is not known, especially as spike-dependent plasticity mechanisms would not be available to non-spiking neurons. Here we use the optic tectum of awake Xenopus laevis tadpoles to determine how a neuron becomes able to generate sensory-driven spikes in vivo. At the onset of vision, many tectal neurons do not exhibit visual spiking behavior, despite being intrinsically excitable and receiving visuotopically organized synaptic inputs. However, a brief period of visual stimulation can drive these neurons to start generating stimulus-driven spikes. This conversion relies upon a selective increase in glutamatergic input and requires depolarizing GABAergic transmission and NMDA receptor activation. This permissive form of experience-dependent plasticity enables a neuron to start contributing to circuit function.
Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK; Nuffield Department of Clinical Neurosciences, University of Oxford, West Wing, John Radcliffe Hospital, Oxford OX3 9DU, UK.
Joram J
JJ
van Rheede
Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK; University of Toronto Scarborough, Department of Biological Sciences, 1265 Military Trail, Science Wing, Toronto, ON M1C 1A4, Canada.
Blake A
BA
Richards
Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK. Electronic address: colin.akerman@pharm.ox.ac.uk.
Colin J
CJ
Akerman
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology*; D000367:Age Factors; D000818:Animals; D003198:Computer Simulation; D004558:Electric Stimulation; D018682:GABA Agents / Q000494:pharmacology; D018698:Glutamic Acid / Q000494:pharmacology; D007814:Larva; D008959:Models, Neurological; D009068:Movement / Q000502:physiology; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D018408:Patch-Clamp Techniques; D010775:Photic Stimulation; D013477:Superior Colliculi / Q000166:cytology*; D013569:Synapses / Q000187:drug effects / Q000502:physiology; D014785:Vision, Ocular / Q000502:physiology*; D014795:Visual Pathways / Q000502:physiology; D014851:Wakefulness; D014982:Xenopus laevis; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology
D018682:GABA Agents; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid