Monkey see, monkey feel

KUWAIT TIMES

Published Date: October 06, 2011

PARIS: Monkeys implanted with brain electrodes were able to see and move a virtual object and sense the texture of what they saw, a step forward in the quest to help the severely paralysed touch the outside world once more. "Someday in the near future, quadriplegic patients will take advantage of this technology," said lead investigator Miguel Nicolelis, a professor of neurobiology at Duke University in North Carolina. They will seek "not only to move their arms and hands and to walk again, but also to sen
se the texture of objects placed in their hands, or experience the nuances of the terrain on which they stroll with the help of a wearable robotic exoskeleton".

Publishing their work yesterday in the British journal Nature, Nicolelis's team implanted multiple electrodes in both brain hemispheres in two rhesus monkeys. Using brain power, the monkeys manipulated a virtual paw to reach up to three identical objects displayed on a computer screen. Touching one of the objects that had a specific tactile feedback - in essence, getting a sensation of its "surface" - gave the monkeys a reward of fruit juice. Holding the virtual paw over the wrong object cancelled the tria
l. It took one monkey only four attempts, and the other nine attempts, before they figured out how to select the right object. Scans of brain activity showed that they were actually sensing the object and not selecting it randomly.

The work adds an important dimension to the search, still confined to laboratories, to restore control over objects to paralysed individuals by connecting their brain to computers and control machinery. Instead of a "brain-machine" interface, the possibility now is of a "brain-machine-brain" interface, or BMBI, say the scientists. In the case of the monkeys, a population of 50-200 cells in the primary motor cortex controlled the avatar arm.

At the same time, the monkeys were getting electrical feedback of the texture of the object through the implants in the primary somatosensory cortex. It is this simultaneous move-and-touch that is the breakthrough, said Nicolelis. "Such an interaction between the brain and a virtual avatar was totally independent of the animal's real body, because the animals did not move their real arms and hands, nor did they use their real skin to touch the objects and identify their texture. It's almost like creating a
new sensory channel through which the brain can resume processing information that cannot reach it anymore through the real body and peripheral nerves.

The fact that this was achieved with non-human primates makes it doubly exciting. In the not-too-distant future, Nicolelis hoped, it may be possible to create a robotic external skeleton that not only restores movement by direct control of the brain but also gives sensation of surfaces. An international scientific team called the Walk Again Project has proposed carrying out a demonstration of a BMBI exoskeleton at the opening match of football's 2014 World Cup in Brazil, Duke University said in a press rel
ease.

Separately, US scientists for the first time have used a cloning technique to get tailor-made embryonic stem cells to grow in unfertilized human egg cells, a landmark finding and a potential new flashpoint for opponents of stem cell research. The researchers were trying to prove it is possible to use a cloning technology called somatic cell nuclear transfer, or SCNT, to make embryonic stem cells that match a patient's DNA.

The achievement, also published yesterday in the Nature, is significant because such patient-specific cells potentially can be transplanted to replace damaged cells in people with diabetes and other diseases without rejection by the immune system. This technique could ignite new controversy because some opponents consider it to be cloning, which they fiercely oppose. "This paper will be seen as significant both by those who are trying to use SCNT to produce human patient-specific embryonic stem cell lines
and by those who oppose human 'cloning' experiments," said Professor Robin Lovell-Badge, a division head at Britain's National Institute for Medical Research.

Stem cells are the body's master cells, the source material for all other cells. Proponents of embryonic stem cells say they could transform medicine, providing treatments for blindness, juvenile diabetes or severe injuries. Normally, SCNT involves removing genetic material from the nucleus of the host egg cell and replacing it with the nucleus from adult cells, the technique used to clone animals such as Dolly the sheep in 1996. But scientists so far have failed to get these cells to grow and divide beyon
d a very early stage in humans and non-human primates.

Scientists in this study, led by Dieter Egli and Scott Noggle at The New York Stem Cell Foundation Laboratory in New York, kept the genetic material from the host egg and simply added the nucleus from the adult cells. "Rather surprisingly - as this means that they are creating an embryo with too many copies of each chromosome - these constructs developed well and efficiently to the blastocyst stage (the stage just before implantation, where the embryo is about 80 to 100 cells)," Lovell-Badge said in a stat
ement. She said the result falls short because the scientists did not obtain useful cell lines, but they may help explain why other techniques have failed.

Embryonic stem cells are made from embryos that are just a few days old, but have been a point of controversy for some religious conservatives, who believe the destruction of any human embryo is wrong. Scientists typically harvest embryonic stem cells from embryos leftover at fertility clinics, but the eggs in this study came from women who were paid around $8,000, roughly the same rate women are paid for egg donations for in-vitro fertilization.

Scientists have debated whether researchers should pay women for eggs used in stem cell research for fear the payments would act as an inducement to women to donate their eggs, a procedure and can take weeks, can cause discomfort and has some risk. The goal of these studies is to work out the best ways to create cells that are "pluripotent" -meaning they can be used to form any other kind of cell in the body. Embryonic stem cells have this capability, but these cells cannot be tailored to match a specific
patient's DNA, and treatments made from these cells might face rejection from the body, much like transplanted organs. In 2006, scientists discovered a new way creating embryonic-like stem cells in the lab using patients' own skin cells and a potent mix of genes or "factors" that can turn back the clock on the adult cells, restoring them to a pluripotent state. - Agencies