Delayed spontaneous alternation in weaver mutant mice.

Weaver mutant mice alternated above chance levels but less often than normal mice in a 2-trial spontaneous alternation test. When the inter-trial (or retention) interval was manipulated, the weaver mutants alternated above chance levels only at the shortest (15 s) but not at the longest (4 or 5 min) intervals, contrary to normal mice that alternated above chance levels at all 3 intervals. Results are discussed in terms of a role for the cerebellum in spatial working memory.