The effects of the lurcher mutation on object localization, T-maze discrimination, and radial arm maze tasks

The Lurcher mutation is characterized by degeneration of the cerebellar cortex and cerebellar ataxia. The mutants were compared to littermate controls of the same background strain in three spatial tasks: 1) left-right discrimination in a water-filled T-maze, a reference memory task requiring a win-stay strategy; 2) the radial arm maze, a working memory task requiring a win-shift strategy; 3) object localization, a reference memory task requiring the use of cognitive mapping. Lurcher mutants were impaired in the object localization and radial arm maze tasks but not in the left-right discrimination task. These results indicate that trial-independent tasks and reference memory tasks using cognitive mapping may be particularly vulnerable to cerebellar degeneration.