Visual information processing by intracerebral retinal transplants in rats.

We have developed a simple system involving the implantation of retinae over the midbrain of rodents to examine whether, in a clearly defined system such as the primary optic pathway, it is possible to re-create circuits lost as a result of injury or developmental disorder. For much of the work, immature rat hosts have been used, in part to maximise optimal conditions and to provide a baseline for similar transplants in adults. In this review we summarise the sequence of studies that has led us to the conclusion that transplanted retinae are capable not only of differentiating and responding to light but also of relaying luminance information to visual centres of the host brain where appropriate behavioural responses are elaborated.