Topic: multiphoton holographic optogenetics

Although most synapses within the neocortex are recurrent, the functional impact of this recurrence remains unclear. Prior experimental and theoretical work in the primary visual cortex (V1) suggests that recurrent excitation amplifies responses when signals are weak in order to optimize detection, while recurrent inhibition suppresses responses when signals are strong to optimize discrimination. Deepening our understanding of the logic for when recurrent activity facilitates cooperation among cortical ensembles and when it mediates competition beyond these initial results is fundamental to un

Recent experiments that stimulate a small number of excitatory neurons appear to offer conflicting results regarding the role of recurrent circuitry in the mouse primary visual cortex. Marshel et al. (2019) found that stimulating 20 neurons could drive behavior, suggesting that this circuitry has strong amplifying qualities. However, Chettih and Harvey (2019) show that single-neuron perturbations drive network suppression and feature-specific competition. Here, we attempt to reconcile these results using multiphoton holographic optogenetics and mathematical modeling. Specifically, we use spa