Experiments with monkeys: Our second example, of at least trying to rehabilitate, is of a few monkeys who had holes in their visual field (scotomata). When food pellets and other objects were placed in positions on the table corresponding to the holes in their visual field, the monkeys did not notice them. The accepted opinion is that there would be no point in trying to train the monkey to see the food pellets. Instead, in this view, it would be better to place the food pellets in positions which could be seen (that is compensating).
However the experimenter decided to try to train the monkeys to see in these 'blind spots'. Nothing special was done in the training. A great deal of time was spent in rewarding the monkey for 'looking' at the right area. Eventually the monkeys were found to act as if they could indeed see in those previously 'blind spots'. And when the brains of the monkeys were cut up (much later!) it was found that the scotoma was greatly reduced.