A Translaminar Spacetime Code Supports Touch-Evoked Traveling Waves.

Unlabelled: Linking sensory-evoked traveling waves to underlying circuit patterns is critical to understanding the neural basis of sensory perception. To form this link, we performed simultaneous electrophysiology and two-photon calcium imaging through transparent NeuroGrids and mapped touch-evoked cortical traveling waves and their underlying microcircuit dynamics. In awake mice, both passive and active whisker touch elicited traveling waves within and across barrels, with a fast early component followed by a variable late wave that lasted hundreds of milliseconds post-stimulus.

Bioelectronics for Millimeter-Sized Model Organisms.

Advances in microfabrication technologies and biomaterials have enabled a growing class of electronic devices that can stimulate and record bioelectronic signals. Many of these devices have been developed for humans or vertebrate animals, where miniaturization allows for implantation within the body. There are, however, another class of bioelectronic interfaces that exploit microfabrication and nanoelectronics to record signals from tiny, millimeter-sized organisms.

A microfluidic-induced C. elegans sleep state.

An important feature of animal behavior is the ability to switch rapidly between activity states, however, how the brain regulates these spontaneous transitions based on the animal's perceived environment is not well understood. Here we show a C. elegans sleep-like state on a scalable platform that enables simultaneous control of multiple environmental factors including temperature, mechanical stress, and food availability.

Microfluidics for electrophysiology, imaging, and behavioral analysis of Hydra.

The nervous system of the cnidarian Hydra vulgaris exhibits remarkable regenerative abilities. When cut in two, the bisected tissue reorganizes into fully behaving animals in approximately 48 hours. Furthermore, new animals can reform from aggregates of dissociated cells.

Scalable electrophysiology in intact small animals with nanoscale suspended electrode arrays.

Electrical measurements from large populations of animals would help reveal fundamental properties of the nervous system and neurological diseases. Small invertebrates are ideal for these large-scale studies; however, patch-clamp electrophysiology in microscopic animals typically requires invasive dissections and is low-throughput. To overcome these limitations, we present nano-SPEARs: suspended electrodes integrated into a scalable microfluidic device.