Intra- and Inter-Individual Variability of Executive Functions: Determinant and Modulating Factors in Healthy and Pathological Conditions

Executive functioning generally refers to the ability to organize thought and action based on intentions and goals, especially in novel, complex, or difficult situations. Executive functioning is a multifaceted psychological construct that, according to some authors, may be depicted as a set of related but separable high-level cognitive abilities, which may be supported by the prefrontal cortex and may be implemented by larger networks. Many models exist that emphasize commonalities or differences among various executive functions, debating both the number and type of functions identified. Regardless, most scholars agree, however, that these abilities show high intra- and inter-individual variability in terms of their cognitive and behavioral manifestations.

Recent research has begun to unveil the factors that might explain this variability, in terms of both determinant and modulating factors. For instance, neuro-anatomical (e.g., cortical thickness, brain volume, effective connectivity) and neuro-functional (e.g., functional connectivity) characteristics, genetic (e.g., presence/absence of certain polymorphisms) and environmental (e.g., education, occupational achievement and engagement in socially stimulating activities) influences, developmental (e.g., early maturational processes or senescence) and pathological (e.g., lesions, neurodegenerative or psychiatric disorders) mechanisms, may all contribute to intra- and inter-subject variability in executive functions in ways that have not been fully discovered yet. Moreover, it is desirable to explore the degrees of freedom that scientists and clinicians have in terms of the tools that might help modulate this variability, ideally by allowing performance improvements or functional restoration in executive functioning, including brain stimulation, neurofeedback, or cognitive training.

The goal of this Research Topic is to unify the contributions of different research groups investigating the sources of variability in executive functions, discussing the most recent developments, integrating the knowledge accumulated across different fields, and inspiring new multi-faceted models that might explain how executive functions could be better understood, modulated, and improved both in healthy and in pathological conditions. We therefore welcome empirical, theoretical and meta-analytical work involving both clinical and healthy human populations that advance our understanding of intra- and inter-individual variability in executive functioning.