High intellectual ability and the gut-brain-sex steroids axis: a perspective on cognitive and emotional diversity

The gut-brain axis is a bidirectional communication network integrating neural, endocrine, immune, and metabolic signals that regulate neurodevelopment, cognition, and emotion. It contributes to neurotransmitter production, inflammatory regulation, and the microbial metabolism of sex steroids, processes that have been shown to modulate synaptic plasticity and emotional behavior in experimental and clinical contexts, although their specific relevance to high intellectual ability remains unknown. In this perspective, we propose that high intellectual ability could be explored as a heterogeneous construct, within which some individuals identified as having HIA may exhibit responses potentially associated with differential sensitivity to gut-brain-sex hormone interactions. We discuss that microbial modulation of steroid bioavailability and neuroactive metabolites may represent one hypothetical pathway through which variations in steroid bioavailability and neuroactive metabolites could intersect with cognitive performance and emotional intensity, traits frequently described in some individuals with HIA. Integrating evidence from neuroendocrinology, microbiome science, and cognitive neuroscience, we outline a conceptual framework linking microbial, hormonal, and neural processes. This model aims to stimulate empirical research examining how physiological variation across the gut-brain-sex hormone axis may underlie cognitive and emotional diversity in gifted subpopulations. Importantly, this framework is conceptual and extrapolates from converging evidence in microbiome science and neuroendocrinology, as direct empirical studies in high intellectual ability are currently lacking.