Probe trials after single and sequential controlled cortical impact (CCI) and closed head injury (CHI). (A) Compared with sham-injured mice, all four injury groups (CCI, CHI [53 g], CCI-CHI [53 g], and CHI [53 g]-CCI) had probe trial deficits (p<0.001 analysis of variance [ANOVA], p<0.05 for each group vs. combined sham CHI and sham CCI mice). No differences in probe trial deficits (p=0.3 ANOVA) were observed among the four CHI (53 g) injury groups. (B) Using CHI (83 g), all three injury groups had probe trial deficits compared with sham-injured mice (p<0.01 ANOVA; *p<0.05 vs. sham-injured) but no differences were detected among injury groups.