Adrenalin (epinephrine) injection paradigm

The paradigm at the historical center of cognitive-appraisal theory. By injecting adrenalin to create bodily arousal without an emotional eliciting event, experimenters could ask whether arousal alone constitutes emotion — a direct probe of the James–Lange premise.

Historical arc (Friedman + Dror)

• Marañón (1924): adrenalin injections yielded mostly “cold” or “as-if” emotion in predisposed patients — arousal without a precipitating cause rarely produced genuine felt emotion. The single source Schachter & Singer actually cited in their original manuscript (see dror-2017-two-factors).
• Cantril & Hunt (1932); Landis & Hunt (1932): English-language adrenalin-injection studies testing James–Lange — added to Schachter–Singer only at a reviewer’s request.
• Schachter & Singer (1962): the definitive form — epinephrine × (informed/uninformed/misinformed) × (euphoric/angry confederate). Uninformed subjects “caught” the confederate’s emotion; informed subjects (who could attribute arousal to the drug) did not → arousal + cognitive label = emotion. See stanley-schachter, friedman-2010-jamesian-perspective.
• Schachter–Wheeler (1962): added chlorpromazine (sympathetic blocker) and replaced the stooge with a funny movie — showing any cognition, not social contagion, explains arousal.

Two verdicts in the wiki

• Friedman: the paradigm’s physiological assumptions were naïve; it wrongly cemented “undifferentiated arousal” against autonomic-specificity.
• Dror: the paradigm was, historically, a vehicle for a social-influence research program, later reframed as a physiological/James–Lange story. See origins-of-two-factor-theory.