# Exploring Visual Perceptions of Spatial Information for Wayfinding in Virtual Reality Environments
## Materials and Methods
### Experiment Procedure and Participants  
The VR experiment was conducted over two days from 10 January 2019 to 11 January 2019, and the participants were 24 undergraduate or graduate students. All participants had a visual acuity or corrected visual acuity score of 0.5 or higher, with an average age of 24.8 years (standard deviation: \(\pm\)1.89). A preliminary experiment was conducted to verify the experimental setting. In the preliminary experiment, participants were asked to follow simple instructions after focus adjustment, which allowed them to adapt to the immersive VR environment before entering the main experiment (see Figure 2). The respondents observed the visual stimuli freely for 60 s, and as they had in the preliminary experiments, they explored the virtual space by freely turning their heads and bodies within the range allowed by the HMD equipment. The experimenter ended the preliminary experiment after monitoring the participants' behavior in real time. After the completion of the preliminary experiment, participants entered the main experiment, and the time required for each participant to complete it was different; the participants took a minimum of four minutes and a maximum of five minutes and 40 s. According to the validity rate of data collection, the gaze data of 11 final selected participants were selected and analyzed. Figure 1: Visual stimuli for experimental procedures with a map of the experimental site. The stimulus images in the diagram are flattened, 360-degree images to indicate the experiment’s setting. (**a**) As a focus adjustment step for extracting the gaze data of each subject, subjects performed the focus data test in a 360-degree space. The images (**b**) and (**c**) show the subjects’ exploration of the surrounding environment, while the researcher explained the visual stimuli to the subjects, including signs and crossroads in the indoor space, via a “presentation of purpose statement”. (**d**) As a step in extracting the gaze data, the participants viewed the signs and searched the space according to the purpose statement. (**e**) The researchers interviewed the participants about how they understood the space in the process of exploring it. Figure 2: Experimental steps and visualization of the laboratory layout. (**a**) Layout of the virtual reality (VR) experiment. (**b**) The experimenter helps the participant wear the head mounted display (HMD) and adjusts its focus according to the nine points. (**c**) The experiment proceeds according to the visual stimulus stages. (**d**) After the VR experiment, the participant answer questions about the spatial information and their perceived consciousness. The initial data for visual stimulus were reviewed to exclude participants whose validity rate was less than 85%. This was to increase the accuracy and the reliability of the experimental data by examining the validity rate in the process of recording the participants' gaze data in real time. Data from 11 out of 24 participants (45.83%) were valid and were selected. The percentage of valid initial data was 69.2%, but this rate was increased to 92.9% by the inclusion of 11 participants with validity rates of higher than 85%. The extracted data were analyzed according to the validation of the effective rate. The visual stimuli used in the experiment were photographic images taken across 360 degrees. The participants performed in the experiment by observing a fixed virtual space image. AOI is an analysis method that can observe gaze fixation within the designated area to which the participants' gazes were directed. For the setting of AOIs and the extraction of data, the SMI BeGaze 3.6 program was used. The experimenter can designate a specific region of interest within the entire spatial image to extract gaze movements generated within that region. The change of gaze can be analyzed using the quantitative data of gaze movements, which is used to obtain information on wayfinding by mapping participants' cognitive processes of visual perception.