Two-Factor Theory of Emotion Lab

Physiological Stimulus

Injection dose (arousal drive) 25%

Arousal rise/decay rate τ 2.5s

Situational Appraisal

Awareness of Cause

Felt Emotion

Current label

Neutral

Arousal

25%

Heart rate

80 bpm

Valence

0.00

Misattribution m

1.00

How it works

Schachter & Singer's two-factor theory of emotion (1962) says a felt emotion needs two ingredients: unexplained physiological arousal, and a cognitive appraisal of the situation that labels it. Arousal alone (e.g. from an injected stimulant) is emotionally neutral — the mind searches the environment for a plausible cause and borrows its emotional colour.

Arousal (leaky integrator, physiological):
  dA/dt = (S − A) / τ        A ∈ [0,1], S = injection dose

Felt valence (only manifests once aroused):
  V = V_target(appraisal) · m · A
  m = 0.30  if informed about the injection's real cause
  m = 1.00  if uninformed → arousal is misattributed to the situation

Emotion label = nearest octant on Russell's (1980) valence-arousal
circumplex, atan2(A_c, V) in 45° sectors.

Injection dose — sets the target physiological arousal S the leaky integrator chases.
τ slider — how fast arousal rises/decays toward the dose (adrenaline pharmacokinetics).
Appraisal buttons — the situational cue (a euphoric, neutral, or angry confederate in the original experiment) that supplies a candidate label.
Awareness toggle — informed subjects correctly attribute arousal to the injection and barely adopt the confederate's mood; uninformed subjects misattribute it and swing hard toward the appraisal.

The marker on the floor plane tracks (valence, arousal) live; the pulsing core at the centre visualises heart rate, and the drifting particle swarm's spread grows with arousal intensity.

High arousal Low arousal Positive valence Negative valence

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