No significant correlation was found between the distance moved by the animals in the novel environments and the density of c-Fos-ir cells in any of the brain areas (HF: r = 0.207, p = 0.272; TnA: r = 0.122, p = 0.521; IMM: r = 0.183, p = 0.334; LM: r = 0.281, p = 0.132). Here, FOS is linked to hydrops fetalis.