Results of Experiment 1.

<p>Mean values of the controller bars on FaceTool software for the four conditions to make changes to the facial parts are indicated using FACS (facial action coding system) names, accompanied by AU (Action Unit) numbers. Standard errors of the mean are shown in parentheses. Asterisks indicate values significantly larger than zero. ⁺: <i>p</i><0.10; *: <i>p</i><0.05; **: <i>p</i><0.01; ***: <i>p</i><0.001.</p

Examples of the Noh mask images in Experiment 1.

<p>(<b>A</b>) shows the frontal image of the Koomote mask presented at the beginning phase for all the four conditions. Participants changed facial parts of this image to create expressions according to the instructions given in each condition. (<b>B</b>) and (<b>C</b>) show the examples of faces that participants created in the happy and sad conditions, respectively. (<b>D</b>) and (<b>E</b>) show the upward tilted and downward tilted Koomote masks presented simultaneously with the frontal image in these conditions. (<b>F</b>) and (<b>G</b>) show the examples of faces that participants created by imitating (<b>D</b>) and (<b>E</b>), respectively.</p

A schematic illustration summarizing the main results of Experiment 1.

<p>Depicted are the emotions represented differentially by each facial part of the upward tilted and downward tilted Noh masks.</p

Noh mask images used as stimuli.

<p>(<b>A</b>) The 12 Noh mask images having overlaid shadows used in Experiment 1. Koomote, Zoonna, Juroku, and Doji each refers to the different type of the Noh mask. For each mask, there were three conditions regarding the emotional facial expressions: happy, neutral, and sad. (<b>B</b>) Test images used in Experiment 2, having shadows of the vertically tilted images overlaid to the frontal mask.</p

Numbers of participants for each proportion of “happy” evaluation in Experiment 2, shown for each synthesized facial pattern.

<p>“100%” in this graph means that the facial pattern was evaluated as “happy” for all the four repeated presentations, whereas “0%” means that the pattern was evaluated as “sad” for all the four repetitions.</p

Results.

<p>(<b>A</b>) Proportion of the “happy” evaluation for each Noh mask type (i.e., Koomote, Zoonna, Juroku, and Doji) and shadow condition (i.e., sad, neutral, and happy) in Experiment 1. (<b>B</b>) Proportion of the “happy” evaluation for each shadow inclination in Experiment 2. The dashed horizontal lines indicate the chance proportion of the “happy” responses (50%). Error bars indicate standard errors of the mean.</p

Diagram depicting examples of trials in the test session of Experiment 2.

<p>The letters on the first and third displays indicate “Trial 1” and “Trial 2”, respectively.</p