The criticome as the window of becoming: Toward a novel and comprehensive framework for understanding the critical period of information integration in human development.

Critical periods of synaptic plasticity represent windows of extraordinary neural malleability that fundamentally shape brain architecture and function and can determine brain health for decades to come. Yet neuroscience lacks adequate terminology to describe the totality of experiential information integrated during these periods. We propose a conceptually novel term: criticome, as the complete ensemble of sensory, motor, social, cultural, and environmental information recorded during critical periods from prenatal development through approximately age 25, with the recognition that this boundary is probabilistic and domain-specific rather than fixed. Our original framework is grounded in six coupled neurobiological mechanisms: GABAergic regulation through parvalbumin-positive interneurons, perineuronal net dynamics, myelination, epigenetic regulation, neuromodulatory maturation, and developmental synaptic pruning. Their collective state determines what experience can be integrated and how stable the outcome is. The criticome reframes cultural specificity, implicit bias, aesthetic preference, and interpersonal attraction as variations in integrated content rather than differences in brain architecture, and reconceptualizes autism, schizophrenia, post-traumatic stress, major depression, and culture-bound syndromes as developmental rather than purely synaptic disorders. The same plasticity that allows Mozart to emerge from early auditory exposure also produces the lasting damage seen in institutional deprivation, ideological indoctrination, and chronic geopolitical trauma. This framework carries practical consequences for therapeutic timing, educational policy, cultural competence in mental healthcare, and interventions aimed at reopening plasticity in adulthood, while simultaneously raising urgent questions about how screen-mediated environments now shape criticomes during the windows when neural architecture is most malleable.