Topic: basal dendrites

The neocortex is composed of a hierarchy of regions and is thought to perform sensory inference by combining two complementary information streams: 1) a feedforward stream propagating bottom-up in the hierarchy, representing sensory information, and 2) a feedback stream propagating top-down, representing expectations or priors derived from contextual information integrated in higher-order associative regions. Within a cortical region, pyramidal neurons in layers 2 & 3 are a key cellular component of the feedforward pathway which integrate these two streams at their basal and apical dendrit

Anatomically segregated apical and basal dendrites of pyramidal neurons receive functionally distinct inputs, but it is unknown if this results in compartment-level functional diversity. Hippocampal place cells exhibit representational drift (Ziv et al., 2013), but this has only been characterized with somatic recordings. While dendritic activity is implicated in the formation of stable place fields and shaping hippocampal activity, in vivo studies of hippocampal dendritic activity have largely been confined to basal dendrites (Sheffield and Dombeck, 2015) or small cross-sections of apical den

Pyramidal neurons have prominent apical dendrites that are hypothesised to modulatesomatic output. In the visual cortex, apical dendrites may receive contextual signals via top-down inputs and local inhibition. It is not known, however, what causal effects they play indriving or suppressing somatic activity, and how they shape a neuron’s visual tuning.We recorded activity of pyramidal neurons sparsely expressing GCaMP7s in layer 5 of visualcortex in awake mice before and after pruning their apical dendrites with two-photondendrotomy. Together with the neuron’s receptive field and orientation/d

This study takes an analytic approach to delve into the dynamics of pyramidal neurons, focusing on interplay of the basal and perisomatic regions. A significant portion of recurrent excitatory connections converge onto the basal dendrites, generating N-Methyl-D-Aspartate (NMDA) driven depolarizations, also known as NMDA-spikes. The time-scale of NMDA-spikes significantly surpasses the neuronal membrane time-scale by a factor of five, underscoring their relevance in information integration. The voltage dynamics within the dendric subunits remain unaffected by somatic spikes, enabling their inde

Neurons receive correlated levels of excitation and inhibition, a feature that is important for proper brain function. In fact, a dysregulation in the balance between excitation and inhibition has been linked to many neurodevelopmental disorders, including autism, schizophrenia, and epilepsy. However, how this relationship between excitatory and inhibitory inputs is established during the dynamic period of circuit wiring remains unexplored. Using multiple techniques, including in utero electroporation, electron microscopy and electrophysiology, we reveal a tight correlation in the distribution