At behavioural level, higher IGF1-levels were related with better executive functioning (elderly: Al-Delaimy et al., 2009; Bellar et al., 2011; Frater et al., 2018), and higher IGFPB-1 levels with slower processing speed (patients with multiple sclerosis: Butti et al., 2022). Here, IGF1 is linked to multiple sclerosis.