Harp, N., Langbehn, A. T., Larsen, J., Niedenthal, P., & Neta, M. (2022). Facial coverings differentially alter valence judgments of emotional expressions. PsyArXiv. https://doi.org/10.31234/osf.io/5a9fd

The nonverbal aspects of public speaking are just as important as the verbal arguments.

Watzlawick, Bavelas, and Jackson in "The pragmatics of Human communication lists five axioms. The first axiom is "one cannot not communicate" or that every human behavior is a form of communication. Nonverbal communication is its own discipline in communication studies.