Egocentric Direction and Position Perceptions are Dissociable Based on Only Static Lane Edge Information

Abstract

When observers perceive several objects in a space, at the same time, they should effectively perceive their own position as a viewpoint. However, little is known about observers’ percepts of their own spatial location based on the visual scene information viewed from them. Previous studies indicate that two distinct visual spatial processes exist in the locomotion situation: the egocentric position perception and egocentric direction perception. Those studies examined such perceptions in information rich visual environments where much dynamic and static visual information was available. This study examined these two perceptions in information of impoverished environments, including only static lane edge information (i.e., limited information). We investigated the visual factors associated with static lane edge information that may affect these perceptions. Especially, we examined the effects of the two factors on egocentric direction and position perceptions. One is the “uprightness factor” that “far” visual information is seen at upper location than “near” visual information. The other is the “central vision factor” that observers usually look at “far” visual information using central vision (i.e., foveal vision) whereas ‘near’ visual information using peripheral vision. Experiment 1 examined the effect of the “uprightness factor” using normal and inverted road images. Experiment 2 examined the effect of the “central vision factor” using normal and transposed road images where the upper half of the normal image was presented under the lower half. Experiment 3 aimed to replicate the results of Experiments 1 and 2. Results showed that egocentric direction perception is interfered with image inversion or image transposition, whereas egocentric position perception is robust against these image transformations. That is, both “uprightness” and “central vision” factors are important for egocentric direction perception, but not for egocentric position perception. Therefore, the two visual spatial perceptions about observers’ own viewpoints are fundamentally dissociable.

The Role of Quiet Eye Timing and Location in the Basketball Three-Point Shot: A New Research Paradigm

“…Why was a long duration ego-centric QE during arm flexion a factor in performance? Nakashima et al (2015, p. 2) defines ego-centric spatial perception as “the perception of direction or position of oneself based on visual information acquired in the visual field.” Results showed that the participant’s focus was entirely on the ball prior to the catch, followed by a saccade during which vision was suppressed. Therefore vision of the target did not become possible until the onset of QE arm flexion, which occurred half way through the trial between 650 and 700 ms, or 50% of trial time.…”

Peripersonal versus extrapersonal visual scene information for egocentric direction and position perception

“…Stimuli. As Nakashima et al (2015), we rendered one threedimensional (3D) model of a straight portion of a two-lane road, using Shade 11 software (e-frontier, Inc., Japan). The road images subtended 66° × 40° (viewing distance: 60 cm).…”

“…In the three viewing position images, viewing direction was always aligned with road direction. The degrees of the direction (2°) and position (10%) changes were the same as those in Nakashima et al (2015). It is noted that these values were chosen based on the results of a pilot study that the accuracies of the tasks were 70%-80% in these direction and position changes condition (i.e., not ceiling and floor effects).…”

“…Recently, we directly examined the properties of observers’ perception of their own direction and position, termed egocentric direction perception and egocentric position perception. We used a driving-like situation in which people were required to perceive their direction and position in a lane via visual information (Nakashima, Iwai, Ueda, & Kumada, 2015). Participants were presented with static road landscapes and judged whether their viewing direction was the same as the road direction and whether their viewing position was at the center of the lane.…”

High-normal blood glucose levels may be associated with decreased spatial perception in young healthy adults

“…Establishing whether high normal blood glucose levels in healthy young adults can have adverse effects on spatial (SVV) perception is worthy, considering that maintaining an average normal glucose level throughout the day may be an important part in performing more efficiently and effectively in activities that require optimal spatial orientation, such as navigation [ 16 ], sports [ 17 , 18 ] and driving [ 19 , 20 ].…”