Assessing Local and Branch-specific Activity in Dendrites

Lateral Entorhinal Cortex Inputs Modulate Hippocampal Dendritic Excitability by Recruiting a Local Disinhibitory Microcircuit

“…Local dSpikes have been reported in vivo in the hippocampus and cortex 36,37,[121][122][123][124] and linked to feature-selective tuning. [36][37][38]48 In CA1, large-amplitude dSpikes, resembling our local dSpikes, occur during coordinated oscillatory activity from CA3 and the EC, without triggering somatic APs. 32 Local dSpikes may serve a function distinct from that of somatic APs by enhancing the electrical and biochemical dendrite-soma coupling.…”

“…[33][34][35]73,106,125,126 Ultimately, soma-independent, branch-specific dendritic activity can greatly expand the computational capacity of a neuron. 44,[127][128][129][130][131][132][133] Integration with other inputs may enable the LEC to drive somatic output and plasticity Under what conditions could excitatory LEC inputs drive somatic spike output? High-frequency burst-like activity and/or integration of coincident inputs could elicit APs by sufficiently depolarizing the somatic compartment.…”

“…GABAergic inhibitory neurons (INs) can serve as effective circuit switches to rapidly and precisely shape single-cell computations. 27,31,[46][47][48] Given their functional diversity and wiring specificity, 49,50 INs can modulate compartment-specific activity to expand the computational coding capacity of single neurons. Various models have predicted important effects of inhibition on local spiking in single neurons.…”

Sub-cellular population imaging tools reveal stable apical dendrites in hippocampal area CA3

“…Beyond differences in the inputs they receive, apical and basal dendrites may differ in their molecular composition, structural and biophysical properties, and function 1 . It is known that dendrites support non-linear processing in the form of dendritic spikes [2][3][4][5][6][7][8] and other ionic conductances 9,10 , which can tremendously enhance the computational capacity of individual neurons [11][12][13][14][15] and support ensemble coding and plasticity [16][17][18] . However, it is unclear if the population activity of apical and basal dendrites differ in terms of content or stability across time.…”

“…It then screens putative calcium transients with an additional goodness-of-fit measure to eliminate spurious activity from undetected ROIs. To demonstrate the efficacy and utility of this approach, we applied it to several sets of data recorded from area CA3 of the mouse hippocampus 33 , an area containing "place cells" crucial for spatial navigation. Using this preparation, we characterized the spatial tuning properties of soma, apical dendrites, and basal dendrites during a simple navigation task.…”