On 19 February 1920 a short clinical observation appeared that is widely cited as the earliest recorded case of contagious yawning being examined in a scientific or medical context. The report was not a large experimental study but a descriptive note from a physician or observer who recorded yawning spreading among people in close quarters. This entry has gained attention in later literature because it predates more systematic investigations into the phenomenon that emerged in the mid-20th century and beyond. Context and nature of the record The 1920 note reflects the medical and observational practices of the time: clinicians and naturalists often published brief case reports and anecdotes in journals and society proceedings. The account describes a situation in which one person’s yawn appeared to trigger yawns in nearby individuals. It does not include modern experimental controls, standardized measures, or hypotheses about neural mechanisms; rather, it is a descriptive observation intended to record a curious social and physiological occurrence. Why the 1920 note matters Researchers who later studied contagious yawning have treated this early record as historically significant because it shows recognition of the phenomenon well before it became a subject of laboratory research. The entry demonstrates that observers were aware of yawning’s social spread and considered it worth reporting, providing a starting point for tracing how scientific attention to the behavior developed. Limitations and caution The 1920 record is not a controlled experiment. It lacks the methodological detail expected in contemporary research: no sample size calculation, no control conditions, and little information about observers’ criteria for counting yawns. Because of these limitations, the note cannot establish frequency, causation, or underlying mechanisms. Later experimental work—beginning in earnest decades later—used video stimuli, standardized protocols, and statistical analysis to address those questions. What later research found From the late 20th century onward, researchers investigated contagious yawning with controlled methods. Studies examined whether seeing, hearing, or imagining yawns triggers yawning; whether contagion correlates with empathy and social bonding; and how susceptibility changes across age and in certain clinical populations. Those studies built on early descriptive records like the 1920 note by providing systematic data, though many questions about neural circuitry and social function remain active areas of research. Historical significance The 1920 observation is best understood as an early, informative entry in a long-running curiosity about yawning’s social dynamics rather than as definitive evidence about causes. It documents that observers a century ago were attentive to subtle social-physiological interactions and serves as a useful marker in the historical timeline of research on contagious behaviors. If you seek the original source The 1920 account appears in the form of a brief clinical or society note rather than a full empirical paper. For verification and citation, consult archives of medical and naturalist journals from that year or later historical reviews of yawning and social contagion that reference early observations. Because bibliographic records vary, interested readers should check primary-source databases and historical indexes to locate the exact publication.