Considering that obesity is associated with impaired cognitive function (Elias et al., 2005; Cournot et al., 2006; Wolf et al., 2007), leptin resistance may play a role in HPC-dependent memory impairment associated with obesity (see Van Doorn et al., 2017 for further review on this topic). This evidence concerns the gene LEP and obesity due to melanocortin 4 receptor deficiency.