Effects of antiphospholipid syndrome (APS) induction on behavior and cognition in factor V Leiden (FVL) mice. (A) Cognitive function in a swim T-maze alternation test. The results are presents as the mean ± SE proportion (%) of correct choices in eight trials/day over 4 consecutive days. There was significantly impaired learning in the FVLQ/Q-APS mice (P = 0.026 for the interaction days × group, by repeated-measures ANOVA). (B) Anxiety-related behavior in an elevated plus-maze test. The results are presented as mean ± SE time (%) spent in the white (open) arms. Both the FVLQ/+-APS and FVLQ/Q-APS mice spent significantly more time in the white arms compared with FVL-control mice (P < 0.031 by ANOVA), indicating altered levels of anxiety induced by APS in FVL mice. Cumulative data from two independent experiments (FVLQ/+-control (FVL-control), n = 15; FVLQ/+-APS, n = 8; FVLQ/Q-APS, n = 7).