Researchers of the Primate Research Institute at Kyoto University in Japan use chimpanzees' interaction with computers and touch screens to study the cognition and perception of these primates.
When Reo, a male chimpanzee, was paralysed from the neck down, dedicated staff put this technology to further use by encouraging the animal to walk again.
This is the first case in which a paralysed chimpanzee has been rehabilitated through such a dedicated programme.
He gradually recovered enough to sit up, and could later pull himself upright by using suspended ropes.
Intensive physiotherapy over a period of 41 months followed, after which he was able to climb about again using only his arms.
To aid Reo's ultimate integration back among the other twelve animals held at the institute, his carers decided to try to get him walking again.
A computer-controlled monitor was therefore placed on one wall, and cognitive tasks were again put to him.
It was not plain sailing at first, and the research team had to adapt their ideas seven times before they received any cooperation from a somewhat fearful Reo.
Thereafter, whenever he completed a task successfully, a food reward was placed on a tray on the opposite side of the room. This meant that Reo had to move at least two meters to reach it.
At first he did so using a rope for assistance, but gradually he started travelling in an upright seated position which resembled the side-to-side manner of a penguin walking on land.
The rehabilitation sessions encouraged him to increase his movements considerably, and he started walking up to five hundred meters in a two-hour session.
"Cognitive tasks may be a useful way to rehabilitate physically disabled chimpanzees, and thus improve their welfare in captivity," said Yoko Sakuraba of Kyoto University, adding that euthanasia need not be the only option for animals injured in captivity.
