Although visual orientation is vital in postural regulation, the particular properties of postural response to orientation are unclear. For a study, researchers explored the link between postural response and subjective visual vertical (SVV) as a function of scene orientation. They used a helmet-mounted display to show a virtual space with ordinary objects and assessed head tilt around the naso-occipital axis. In 15° increments, the room orientation changed from 165° counterclockwise to 180° clockwise around the middle of the display. They also performed a rod adjustment job in a separate session to record the participant’s SVV in the slanted room. They used a weighted vector sum model to calculate the weight of three visual clues to orientation: frame, horizon, and polarity, and then applied it to head tilt and SVV error. All visual signals contributed significantly to head tilt and SVV error, according to the findings. 

Frame cues had the most influence on SVV inaccuracy, whereas polarity had the least. There was no discernible difference in visual cue types for head tilt, while the sequence of contribution was identical to the SVV. The findings showed that various visual signals to orientation were engaged in postural control and those diverse representations of vertical orientation were used across postural control and perception.

Reference:jov.arvojournals.org/article.aspx?articleid=2778620

Author