The Third Functional Brain Unit in a Shattered World: Revisiting Neuropsychological Dysfunctions Through the Lens of Luria and Vygotsky

Over the past three decades, the global prevalence of neuropsychological and mental health disorders—including schizophrenia, autism spectrum disorders, and obsessive-compulsive disorder—has increased markedly. Drawing on Vygotsky and Luria’s Cultural-Historical Activity Theory (CHAT) and the principle of extracortical brain organization, with the crucial role of speech in internalization and mediation, this paper argues that the crisis of neoliberal individualism disrupts the brain’s “third functional unit” (now commonly termed executive functions), which is responsible for programming, regulating, and verifying goal-directed activity. Neoliberalism’s fragmented narratives, erosion of collective goals, and decline in meaningful sociohistorical praxis foster detachment from reality and its contradictions. The disruption of the third-unit functionality is a source of various pathologies observed in frontal lobe lesions, such as impulsivity, stereotypic behaviors, diminished motivation, impaired problem detection, and difficulties in abstraction and generalization. By synthesizing CHAT with contemporary critiques of neoliberalism and recent findings in neuroscience—particularly on brain socialization and the challenges of diagnosis and treatment—we theorize that the collapse of shared narratives and collective goals intensifies neuropsychological dysfunction, contributing to comorbidities and novel syndromes. Emphasizing the dialectical interplay between brain and sociohistorical context, the paper calls for investigating how alternative collective narratives and practices might mitigate these effects.