Rats with fimbria-fornix lesions can acquire and retain a visual-tactile transwitching (configural) task

The idea that the hippocampus is essential for acquisition and retention of a transwitching (configural) problem is evaluated with a visual-tactile task. The task requires the rats to pull up a string of one of two sizes for food, as signalled by room lighting conditions. Rats received cathodal fimbria-fornix lesions either prior to or after learning the task. Rats with fimbria-fornix lesions were unimpaired in acquisition or retention. The results do not support the position that the hippocampal formation is essential for the acquisition and retention of a transwitching configural problem. The result is discussed in relation to the configural theory of hippocampal function.