The bodily substrate of language: insights from clinical linguistics.

Motor aspects and bodily experience in general have traditionally been considered peripheral in models of neural and functional architecture of language. This opinion paper draws on two clinical case studies to explore the deep connection between sensorimotor components and symbolic processing systems. To this end, we report on the use of the Digital Linguistic Biomarker (DLBs) technique for analyzing speech and writing samples from older adults with dementia and adolescents with anorexia nervosa. In the former case, our data show that well-known cognitive symptoms of neurodegeneration (e.g., memory loss and planning deficits, word retrieval and sentence comprehension difficulties) are preceded by subtle acoustic-articulatory alterations. In the latter case, physical symptoms associated with extreme weight loss are accompanied by a gradual decline in syntactic complexity. Overall, these findings indicate that even in disorders that appear highly selective in nature, the deficits affect communicative competence across multiple interconnected levels that are deeply grounded in sensorimotor processes.