What is the logic underlying neocortical structure and function? Answering this question will require precise measurements and perturbations of specific neuronal populations in behaving animals.
- Quantitative behavior of head-fixed mice
Inspired by work in primates, we have developed a variety of behavioral tasks for head-fixed mice. In one task mice use their whiskers to measure the distance to an object. This task provides exquisite experimental control: the motor programs (whisking and licking) and the sensory inputs (whisker-object contact, force on the follicle) can be precisely measured. In another task mice have to navigate a virtual corridor with their whiskers. These head-fixed behaviors allow us to apply reductionist biophysical techniques, such as whole cell recordings, population imaging with single cell resolution, photostimulation, and local pharmacology to dissect the contributions of specific neurons and neuronal populations to the behavior.
- Mapping somatosensory circuits
We are mapping the functional circuits underlying whisker-based somatosensation at the level of identified groups of neurons. We currently focus on the cortico-cortical, thalamo-cortical, and cortico-thalamic circuits connecting sensory and motor areas. To probe long-range projections we employ a combination of classical anatomy followed-up by ChR2-based circuit mapping. To probe local cortical microcircuits we use glutamate uncaging-based circuit mapping. We are exploring array tomography as a tool for circuit reconstruction.
- Recording and imaging neuronal populations
We use a variety of electrophysiological and imaging approaches to monitor the dynamics of neuronal populations in behaving mice.
- Genetically encoded sensors
We are part of a group of labs (with the Looger, Jayaraman and Kerr labs) helping to develop genetically encoded sensors for neuronal function. Currently we are focusing on calcium indicators.