Figure 1.

Timeline of experimental groups and behavior tests. (a-e) Separate, independent cohorts of C57BL/6J male mice (JAX Cat. #000664) received whole-body exposure to particles of ⁵⁶Fe (a-c, e), ²⁸Si (d), or Sham exposure at 6-months (mon) of age (0-mon post-irradiation [IRR]). (a) ⁵⁶Fe or Sham mice subsequently were run on TS training, PD, PD rev, and LD. (b) ⁵⁶Fe or Sham mice were run on TS training, PAL, and VMCL. (c) ⁵⁶Fe or Sham mice were run on CDFC. (d) ²⁸Si or Sham mice were run on CDFC. (e) ⁵⁶Fe or Sham mice were run on LM, CFC, D/L, and PT, and brains were collected for DCX + cell quantification. For each set of mice shown (a-e), the interval between radiation exposure and behavioral testing was equal between Sham and IRR groups. Specifically, the beginning of each major behavioral test shown above was synchronized in Sham and IRR cohorts. CDFC = contextual discrimination fear conditioning, CFC = contextual fear conditioning, D/L = dark/light box test, Frac = fractionated, IRR = irradiation, LD = location discrimination, LM = locomotor, mon = months, Non-Frac = non-fractionated, PAL = paired associates learning, PD = pairwise discrimination, PD rev = PD reversal, PT = pain threshold, TS = touchscreen, VMCL = visuomotor conditioning learning.