Noninvasive brain control | MIT News Office

Noninvasive brain control | MIT News Office: MIT engineers have now developed the first light-sensitive molecule that enables neurons to be silenced noninvasively, using a light source outside the skull...

Boyden’s team had previously identified two light-sensitive chloride ion pumps that respond to red light, which can penetrate deeper into living tissue. However, these molecules, found in the bacteria Haloarcula marismortui and Haloarcula vallismortis, did not induce a strong enough photocurrent — an electric current in response to light — to be useful in controlling neuron activity.

Chuong set out to improve the photocurrent by looking for relatives of these proteins and testing their electrical activity. She then engineered one of these relatives by making many different mutants. The result of this screen, Jaws, retained its red-light sensitivity but had a much stronger photocurrent — enough to shut down neural activity.

Stem cells mimic human brain : Nature News & Comment

Stem cells mimic human brain : Nature News & Comment: ...in the latest advance, scientists developed bigger and more complex neural-tissue clumps by first growing the stem cells on a synthetic gel that resembled natural connective tissues found in the brain and elsewhere in the body. Then, they plopped the nascent clumps into a spinning bath to infuse the tissue with nutrients and oxygen...

Under a microscope, researchers saw discrete brain regions that seemed to interact with one another. But the overall arrangement of the different proto-brain areas varied randomly across tissue samples — amounting to no recognizable physiological structure.

“The entire structure is not like one brain,” says Knoblich, adding that normal brain maturation in an intact embryo is probably guided by growth signals from other parts of the body. The tissue balls also lacked blood vessels, which could be one reason that their size was limited to 3–4 millimetres in diameter, even after growing for 10 months or more.

A Videogame That Recruits Players to Map the Brain | Wired Design | Wired.com

A Videogame That Recruits Players to Map the Brain | Wired Design | Wired.com: Created by neuroscientist Sebastian Seung’s lab at MIT, EyeWire basically gamifies the professional research Seung and his collaborators do on a daily basis.

Company Aims to Cure Blindness with Optogenetics

Company Aims to Cure Blindness with Optogenetics: Retrosense is developing a treatment in which other cells in the retina could take the place of the rods and cones, cells which convert light into electrical signals. The company is targeting a group of neurons in the eye called ganglion cells. Normally, ganglion cells don't respond to light. Instead, they act as a conduit for electrical information sent from the retina's rods and cones...
Doctors would inject a non-disease causing virus into a patient's eye. The virus would carry the genetic information needed to produce the light-sensitive channel proteins in the ganglion cells. Normally, rods, cones, and other cells translate light information into a code of neuron-firing patterns that is then transmitted via the ganglion cells into the brain. Since Retrosense's therapy would bypass that information processing, it may require the brain to learn how to interpret the signals.

Now I See You - Technology Review

Now I See You - Technology Review: "In mammals' eyes, a set of cells in the retina detects light, and then a separate layer of cells, called ganglion cells, relays that information to the brain. Because macular degeneration and other retinal diseases cause the light-detecting cells to die but leave the ganglion cells intact, researchers have been trying for 50 years to decipher their code—the patterns by which the ganglion cells fire—so as to capitalize on the eye's natural circuitry. Nirenberg has now nailed that, or at least a close approximation. After 10 years of work, she knows the relationship between what we see and how that translates into ganglion-cell firing patterns."

Hi-res detector used by researchers to map neural circuits of the retina

Hi-res detector used by researchers to map neural circuits of the retinaThe retinal readout device that made the experiments possible was inspired by detector technologies that physicists are using to search for the Higgs boson at the Large Hadron Collider. It was developed by an international team of high-energy physicists from the Santa Cruz Institute for Particle Physics (SCIPP) at UCSC, the AGH University of Science and Technology in Krakow, Poland, and the University of Glasgow, U.K. The system records neural signals at high speed (over ten million samples each second) and with fine spatial detail, sufficient to detect even a locally complete population of the tiny and densely spaced output cells known as "midget" retinal ganglion cells.