B: 255, 255, 0). As shown in Figure 1, 15 different shapes were presented, all in black, including the arrow, asymmetrical star, blob, circle, cloud, cross, diamond, drop, ellipse, heart, moon, rectangle, square, star, and triangle. Similar to Woods et al.’s (2013) study, two texture patches were used, including both smooth and rough textures (see Figure 1 for an illustration). Specifically, the smooth texture was visualized as a gray background with sparse granular gray spots, whereas the rough texture was visualized by a gray background with dense granular white spots.
Design and Procedure
A within-participants experimental design was used. That is, all of the participants undertook a total of 28 experimental trials (15 shape trials, 11 color trials, and 2 texture trials) which were presented in a random order. At the beginning of the study, the participants were given instructions as to how to complete the study, and completed a single trial in which they were asked to match the taste word ‘umami’ with one of the following words: paper, purple, savory, sweet, watch, yellow. The experiment continued once the participant had correctly answered this question. Participants were directed to the Wikipedia website4 for the term “umami” in the case that they wanted a description of this term. The purpose of this practice trial was twofold, as it provided an opportunity for the participants to become familiar with both the click-drag-release task, and the meaning of the term “umami.” After this, the participants were instructed to complete each trial as quickly and as accurately as possible and to click ‘start’ to begin the study.
During each trial, a central target (e.g., an image of the cloud shape, as shown in Figure 2) was presented in the center of the screen, with words representing the five basic tastes arrayed in a pentagon-shape around it. The location of each taste word was varied randomly around the pentagon from trial to trial. The participant’s task involved dragging the target to the word that was associated with it. Specifically, the participants were instructed to (1) place the cursor on the target and press the left mouse button, (2) drag the word by moving the mouse (with the left button still being pressed) until the target overlapped with one of the taste words, and (3) to release the target by releasing the left mouse button. Upon making their response, the participants were asked how confident they were that other people would respond in the same fashion as they had, by indicating on a 5-point horizontal scale with the following options, arranged from left to right: Very unconfident, unconfident, uncertain, confident, and very confident. After they had rated their confidence, a “continue” button appeared on the webpage for them to press in order to initiate the next trial. It took ∼8 min to complete the entire study. After completing the experiment, all of the participants were debriefed as to its purpose.
FIGURE 2. An illustrations of the screens on which participants were asked to match the central target with one of the taste terms (upper panel) and to indicate how confident they were about their answer (lower panel).
Data Recording and Analyses
The key dependent variable in this study was the taste word that the participants chose for each target, from the five possible options. That being said, their confidence rating regarding the consensuality of their answer (Koriat, 2008), i.e., the degree to which the participants felt that others would make the same stimulus pairing, was also included in some of the data analyses.
We first analyzed the chosen tastes across the four groups. We combined the data from the four groups of participants, and performed Chi-square tests with Bonferroni’s correction for multiple testing5 to examine whether certain taste(s) were more often associated with a stimulus than other tastes. When the results of these Chi-square tests reached significance, we then performed post hoc Chi-square tests to examine whether the taste that was chosen most often was chosen significantly 