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Yaeger, C. E.

Publications and source records attributed to Yaeger, C. E..

2 recordsLinked to original sources

Plateau potentials are instructive signals for behavioral timescale synaptic plasticity in the neocortex

Learning occurs via the adjustment of synaptic weights across a variety of timescales. The mechanisms supporting these processes, from single-shot to iterative learning, are unclear. The prevailing model in the neocortex, spike-timing dependent plasticity (STDP), requires many pairings of precisely coordinated activity. This is difficult to reconcile with single-shot learning in behaving animals. In hippocampus, an alternative form of plasticity driven by plateau potentials (behavioral timescale synaptic plasticity; BTSP) alters synaptic weights in a single trial to reorganize spatial representations. Here we show that layer 5 pyramidal neurons (L5 PNs) of mouse primary visual cortex (V1) exhibit highly prevalent plateau potentials that drive single-shot changes in sensory representations. Spontaneously occurring and experimentally induced plateaus rapidly and persistently modified L5 PN responses to visual stimuli. In acute slices, plateau potentials drove synapse-specific plasticity with few repetitions across seconds-long pairing intervals. Our results demonstrate that plateau potentials in the neocortex rapidly reshape neuronal representations through BTSP. This instructive form of plasticity provides a mechanism for dynamic adjustment of neocortical synaptic weights to support rapid learning.

neuroscience↗

Dendritic compartmentalization of input-specific integration and plasticity rules across cortical development

Biological and artificial neural networks learn by modifying synaptic weights, but it is unclear how these systems can retain previous knowledge and also acquire new information. Here we show that cortical pyramidal neurons can solve this plasticity-versus-stability dilemma by differentially regulating synaptic plasticity at distinct dendritic compartments. Oblique dendrites of adult mouse layer 5b cortical pyramidal neurons selectively received monosynaptic thalamic input, integrated linearly, and-- surprisingly--lacked synaptic potentiation. In contrast, basal dendrites, which do not receive thalamic input, exhibited conventional NMDA receptor-mediated supralinear integration and synaptic potentiation. Congruently, spiny synapses on oblique branches showed low structural plasticity in vivo. A selective decline in NMDAR activity and expression at synapses on oblique dendrites was controlled by an experience-dependent critical period. Our results demonstrate a new biological mechanism for how single neurons can safeguard a set of inputs from ongoing plasticity by altering synaptic properties at distinct dendritic domains.

neuroscience↗