In the PFC, a significant effect of Exploration was revealed on the BDNF mRNA levels normalized with β-actin [F(1,18) = 8.48; P < 0.01] that were higher in the LE group in the left hemisphere; there was no exploration × left/right hemisphere interaction in ANOVA and indeed a similar difference between the LE and HE groups in the right hemisphere which missed the conventional level of significance was also notable (Fig. 4). This evidence concerns the gene BDNF and hereditary elliptocytosis.