Fig 1.
Illustration of the morph continua (top) and of the display of ambiguous and non-ambiguous expressions during a single trial in the main experiment (bottom). Top: the expressive faces (smiling in the illustration) were morphed with the neutral faces in steps of 10%. Bottom: during a trial, the central large face was one of the morph levels (50% of the smiling face in the illustration; see the red rectangle in the continuum). The lateral smaller faces represent the extrema of all continua for the model (e.g., the “4. neutral” and “3. happiness” faces at the bottom were the faces in blue rectangles in the continuum). The participants were instructed to determine which lateral face the central one more resembled. For half the participants, the emotion names were removed.
Fig 2.
Intensity of expression for correct perception.
Mean minimum intensity of expression (in percentage of expression) in the morphed target faces for correct perception of the expression, according to Odor context and Expression continua (error bars are standard errors of the means).
Fig 3.
Mean percentages of intrusions of other expressions according to Odor context, Expression continuum, and Group (error bars are standard errors of the means).