Impaired spatial performance in cerebellar-deficient Lurcher mice is not associated with their abnormal stress response

•Lurchers had a higher increase of corticosterone level after water exposure.•Lurcher mice showed spatial navigation deficit with residuum of learning capacity.•No decline of the corticosterone level was seen despite mild improving performance.•Adrenal glands of Lurcher mice were larger than in wild type mice.•Enhanced stress response is not the main factor causing spatial deficits in Lurchers.