RT Journal Article
SR Electronic
T1 Differential effects of fornix and caudate nucleus lesions on two radial maze tasks: evidence for multiple memory systems
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 1465
OP 1472
DO 10.1523/JNEUROSCI.09-05-01465.1989
VO 9
IS 5
A1 Packard, MG
A1 Hirsh, R
A1 White, NM
YR 1989
UL http://www.jneurosci.org/content/9/5/1465.abstract
AB The present experiments were designed to examine the hypothesis that the mammalian brain contains anatomically distinct memory systems. Rats with bilateral lesions of caudate nucleus or fimbria-fornix and a control group were tested postoperatively on 1 of 2 versions of the radial maze task. In a standard win-shift version, each of the 8 arms of the maze was baited once, and the number of errors (revisits) in the first 8 choices of each trial was recorded. Fimbria-fornix rats were impaired in choice accuracy, while caudate animals were unimpaired relative to controls. Different groups of rats with similar lesions were tested on a newly developed win-stay version of the radial maze, in which the location of 4 randomly selected baited arms was signaled by a light at the entrance to each arm, and which required rats to revisit arms in which reinforcement had been previously acquired within a trial. Rats with fimbria-fornix lesions were superior to controls in choice accuracy on the win-stay radial maze task, while caudate animals were impaired relative to controls. The results demonstrate a double dissociation of the mnemonic functions of the hippocampus and caudate nucleus. Some implications of the presence of 2 memory systems in the mammalian brain are discussed.