During cortical circuit development in the mammalian brain, groups of excitatory neurons that receive similar sensory information form microcircuits. However, cellular mechanisms underlying cortical microcircuit development remain poorly understood. Here we implemented combined two-photon imaging and photolysis in vivo to monitor and manipulate neuronal activities to study the processes underlying activity-dependent circuit changes. We found that repeated triggering of spike trains in a randomly chosen group of layer 2/3 pyramidal neurons in the somatosensory cortex triggered long-term plasticity of circuits (LTPc), resulting in the increased probability that the selected neurons would fire when action potentials of individual neurons in the group were evoked. Significant firing pattern changes were observed more frequently in the selected group of neurons than in neighboring control neurons, and the induction was dependent on the time interval between spikes, N-methyl-D-aspartate (NMDA) receptor activation, and Calcium/calmodulin-dependent protein kinase II (CaMKII) activation. In addition, LTPc was associated with an increase of activity from a portion of neighboring neurons with different probabilities. Thus, our results demonstrate that the formation of functional microcircuits requires broad network changes and that its directionality is nonrandom, which may be a general feature of cortical circuit assembly in the mammalian cortex.
You may also like
Competition between brain hemispheres during sleep
March 27, 2023Max Planck Institute for Brain Research
New Research Shows How Cultural Transmission Shapes...
March 27, 2023Max Planck Institute for Empirical Aesthetics
Mapping unknown territory
February 27, 2023Max Planck Institute for Biological Intelligence
Modeling the turtle brain provides insights: Routing...
February 15, 2023Max Planck Institute for Brain Research
Amygdala Intercalated Cells: Gatekeepers and Conveyors...
January 19, 2023Max Planck Florida Institute for Neuroscience
Aversive bimodal associations differently impact...
January 19, 2023Max Planck Institute for Chemical Ecology