Abstract: 【Abstract】 Objective To evaluate the impact of psoriasis on spatial learning and memory abilities in mouse models by using Morris water maze. Methods Twenty healthy male C57BL/6J mice aged 10 months were randomly and equally divided into 2 groups: psoriasis group topically treated with imiquimod 5% cream on the back once a day for a week, and control group topically treated with vaseline once a day for a week. After successful establishment of mouse models, the Morris water maze （MWM） test was used to assess the learning and memory abilities in the mice in the 2 groups. Results In the place navigation experiment, the escape latency was significantly longer in the psoriasis group （38.24 ± 13.59 s） than in the control group （14.28 ± 3.80 s, t = 5.37, P < 0.01）. In the spatial probe test, the number of times passing through the platform （1.70 ± 0.95 vs. 5.00 ± 1.76, t = 5.21, P < 0.01）, the duration of stay in the target quadrant （t = 2.80, P < 0.05） and the swimming distance （t = 5.74, P < 0.01） were all significantly lower in the psoriasis group than in the control group. The psoriasis group showed significantly decreased swimming distance in the second quadrant （t = 2.49, P < 0.05）, but significantly longer duration of stay in the fourth quadrant compared with the control group （t = 2.46, P < 0.05）. There were no significant differences in swimming distance or duration of stay in other quadrants between the psoriasis group and control group （all P > 0.05）. Conclusion The spatial learning and memory abilities were impaired in the mouse model of psoriasis.

Key words: Psoriasis, Cognition disorders, Learning disorders, Memory disorders, Disease models, animal, Morris water maze