Outline of steps required for converting experimental psychological tests of social, cognitive, emotional and motivational processes into bio‐behavioral markers for neurodevelopmental disorders. (a) Development of tablet battery. (b) Establishing cross‐domain cognitive profiles for each individual. (c) Identifying subgroups. (d) Validation and qualification of biomarkers, and use in clinical trials.

Delusions are considered to be the mark of madness in popular culture and one of the most severe symptoms of mental distress in clinical practice. In this overview, we acknowledge their adverse effects and raise the question whether they can ever be psychologically or biologically adaptive.