Measuring the effects of early life unpredictability and volatility on the psychological development of individuals. – eLIFUN

This three-year interdisciplinary project aims to study within 3 research axes how different forms of uncertainty that characterize early life environments can shape human psychology in the long-term. Axis 1 will use psychometrics to validate a classification of the ecology of early life uncertainty that distinguishes unpredictability from volatility, that is, stochastic vs genuine changes in the mean value of early life factors of adversity (e.g., family instabilities vs parents divorce). Axis 2 will use computational modelling to study the effects of these two types of early life uncertainty on reward-guided learning. Axis 3 will use pupillometry to address the neurophysiological mechanisms on which these effects may rely. We propose that people who encountered relatively more volatility than unpredictability in early life are more likely to develop an ‘Anxious / Vigilant’ phenotype: assign environmental uncertainty into volatility, increase their learning rates, decrease their computational noise level, and be more prone to anxiety and cluster B personality disorders. By contrast, people who encountered relatively more unpredictability than volatility are more likely to develop a ’Passive’ phenotype: assign environmental uncertainty into unpredictability, decrease their learning rates and behavioural adaptation, increase their computational noise levels, and be more prone to depression and cluster C personality disorders. Finally, people who encounter high levels of overall uncertainty are more likely to develop a ‘Stressful’ phenotype, modifying their exploration/exploitation trade-off and be more prone to stress and complex forms of psychotrauma (e.g., complex PTSD).