Talk: Inferring causal transmission probability from pairwise recordings and optogenetics
Speaker: Mikkel Elle Lepperød, University of Oslo
Title: Inferring causal transmission probability from pairwise recordings and optogenetics
Emcee: Elenor Morgenroth
Backend host: Ali Rigby
Details: https://neuromatch.io/abstract?submis...
Paper link: https://www.biorxiv.org/content/biorx...
Presented during Neuromatch Conference 3.0, Oct 26-30, 2020.
Summary: To study how the brain works, it is crucial to identify causal interactions between neurons, which is thought to require perturbations.
However, when using optogenetics, we typically perturb multiple neurons, producing a confound - any of the stimulated neurons can have affected the postsynaptic neuron.
In this study we show how this produces large biases, and how they can be reduced using the instrumental variable (IV) technique from econometrics.
The interaction between stimulation and the absolute refractory period produces a weak, approximately random signal which can be exploited to estimate causal transmission probability.
When simulating integrate-and-fire neurons, we find that estimates from IV are better than na\"ive techniques.
Presented is a robust analysis framework for mapping out network connectivity based on causal neuron interactions.