General fluid intelligence (gF) is a key cognitive ability allowing us to flexibly adapt to the environment through its preferential linkage to several cognitive abilities, including working memory (WM) and long-term memory. In neuroimaging studies, we demonstrated the relation between WM abilities and sensory memory cortical processes, indexed by the mismatch negativity (MMN) response, that statistically predict the environment based on prior experience. We further examined whether neural sensory memory processes are linked to gF (besides WM), and obtained positive findings with enhanced MMN for higher gF and WM skills. Typical in such studies, sophisticated neuroimaging methods are combined with paper and pencil tests for assessing WM and gF in experimental sessions lasting several hours and requiring the presence of licensed psychologists. The capillary diffusion of computers and the internet permits a different approach to cognitive assessment, adopted thus far mainly in behavioral research. We illustrate ongoing studies using digital self-administered assessment of cognitive abilities and other individual differences in a school setting, allowing a fun, human-error-free, time- and cost-efficient quantification of gF and WM. However, administering such tests via PC and online is not totally problem-free and studies of reliability are still scarce. Future research should deepen the psychometric properties of self-administered digital psychological tests for a successful application to neuroimaging studies investigating the neural bases of individual differences in cognition and emotion.