Effect of different directions of attentional shift on inhibition of return in three-dimensional space

Cue depth influences badminton players' inhibition of return in 3-D static and dynamic scenarios

The inhibition of return (IOR) is a phenomenon where response times (RTs) to a target appearing at a previously cued location are slower than those for an uncued location. IOR can improve visual search efficiency. This study aimed to investigate IOR in badminton athletes at different cue depths using a cue-target paradigm in three-dimensional (3-D) static and dynamic scenarios. The study involved 28 badminton athletes (M age = 21.29, SD = 2.39, 14 males) and 25 non-athletes (M age = 21.56, SD = 2.38, 11 males). In the static scenario (Experiment 1), no significant difference between IOR in cueing near and far conditions. IOR was showed both in cueing the near and far condition. Badminton athletes had a speed advantage than non-athletes. In the dynamic scenario (Experiment 2), only badminton athletes showed IOR in cueing the far-to-near condition, but not for the near-to-far. The present study showed that depth information influenced the IOR only in far-to-near condition. Badminton athletes showed more sensitivity to depth information than non-athletes. Additionally, the study expands the object-based IOR in 3-D dynamic scenario.

Object-based inhibition of return in three-dimensional space: From simple drawings to real objects

Cued to an object in space, inhibition of the attended location can spread to the entire object. Although object-based inhibition of return (IOR) studies in a two-dimensional plane have been documented, the IOR has not been explored when objects cross depth in three-dimensional (3D) space. In the present study, we used a virtual reality technique to adapt the double-rectangle paradigm to a 3D space, and manipulated the cue validity and target location to examine the difference in object-based IOR between far and near spaces under different object representations. The study showed that the object-based IOR of simple drawings existed only in near space, whereas object-based IOR of real objects existed only in far space at first, and as the object similarity decreases, it appeared in both far and near spaces.

Spatial attention based on 2D location and relative depth order modulates visual working memory in a 3D environment

The attentional effect on visual working memory (VWM) has been a heated research topic in the past two decades. Studies show that VWM performance for an attended memory item can be improved by cueing its two-dimensional (2D) spatial location during retention. However, few studies have investigated the effect of attentional selection on VWM in a three-dimensional setting, and it remains unknown whether depth information can produce beneficial attentional effects on 2D visual representations similar to 2D spatial information. Here we conducted four experiments, displaying memory items at various stereoscopic depth planes, and examined the retro-cue effects of four types of cues - a cue would either indicate the 2D or depth location of a memory item, and either in the form of physical (directly pointing to a location) or symbolic (numerically mapping onto a location) cues. We found that retro-cue benefits were only observed for cues directly pointing to a 2D location, whereas a null effect was observed for cues directly pointing to a depth location. However, there was a retro-cue effect when cueing the relative depth order, though the effect was weaker than that for cueing the 2D location. The selective effect on VWM based on 2D spatial attention is different from depth-based attention, and the divergence suggests that an object representation is primarily bound with its 2D spatial location, weakly bound with its depth order but not with its metric depth location. This indicates that attentional selection based on memory for depth, particularly metric depth, is ineffective.

The Inhibition of Return of Sanda Athletes in Three Dimensional Static and Dynamic Scenes

Sanda is a combat sport in which athletes adopt offensive and defensive techniques for barehanded confrontations. Inhibition of return (IOR) describes a phenomenon in which an individual's response time to a target appearing at a previously cued location is slower than to a target appearing at an un-cued location. Because Sanda requires attention skills and fast response times in dynamic situations, a good understanding of IOR among Sanda athletes is important for enhancing their performance. We recruited 180 research participants for a 3-part study - 90 Sanda athletes (age M = 21.56, SD = 2.68; 52 males, 38 females) and 90 college student controls (age M = 21.64, SD = 2.40; 45 males, 45 females). We used the IOR paradigm with virtual reality technology to explore Sanda athletes' IOR in three experimental conditions: three-dimensional (3-D) static, dynamic, and mixed. There was a robust IOR effect in the 3-D static scenario, with the IOR effect larger among Sanda athletes than controls. There were different IOR spread patterns between Sanda athletes and controls, and the IOR effect was weaker or absent when the objects moved. There was a speed advantage for Sanda athletes once a static object started moving. In conclusion, the Sanda athletes' faster response times and more fine-graded IOR in 3-D environments may benefit their visual search in combat, and the reference of the static location may be critical for the IOR effect.

Spatial Inhibition of Return Affected by Self-Prioritization Effect in Three-Dimensional Space

Spatial inhibition of return (IOR) being affected by the self-prioritization effect (SPE) in a two-dimensional plane has been well documented. However, it remains unknown how the spatial IOR interacts with the SPE in three-dimensional (3D) space. By constructing a virtual 3D environment, Posner's classically two-dimensional cue-target paradigm was applied to a 3D space. Participants first associated labels for themselves, their best friends, and strangers with geometric shapes in a shape-label matching task, then performed Experiment 1 (referential information appeared as the cue label) and Experiment 2 (referential information appeared as the target label) to investigate whether the IOR effect could be influenced by the SPE in 3D space. This study showed that when the cue was temporarily established with a self-referential shape and appeared in far space, the IOR effect was the smallest. When the target was temporarily established with a self-referential shape and appeared in near space, the IOR effect disappeared. This study suggests that the IOR effect was affected by the SPE when attention was oriented or reoriented in 3D space and that the IOR effect disappeared or decreased when affected by the SPE in 3D space.

Allocation of attention in 3D space is adaptively modulated by relative position of target and distractor stimuli

Allocation of attention across different depth planes is a prerequisite for visual selection in a three-dimensional environment. Previous research showed that participants successfully used stereoscopic depth information to focus their attention. This, however, does not mean that salient information from other depth planes is completely neglected. The present study investigated the question of whether competing visual information is differentially processed when displayed in a single depth plane or across two different depth planes. Moreover, it was of interest whether potential effects were further modulated by the items' relative spatial position (near or far). In three experiments participants performed a variant of the additional singleton paradigm. Targets were defined by stereoscopic depth information and as such appeared either in a near or far depth plane. Distractor stimuli were displayed in the same or in the opposed depth plane. The results consistently showed that visual selection was slower when target and distractor coincided within the same depth plane. There was no general advantage for targets presented in near or far depth planes. However, differential effects of target depth plane and the target-distractor relation were observed. Selection of near targets was more affected by distractors within the same depth plane while far targets were identified more slowly when the amount of information in closer depth planes increased. While attentional resources could not be exclusively centered to a distinct depth plane, the allocation of attention might be organized along an egocentric gradient through space and varies with the organization of the visual surrounding.

Different visual and auditory latencies affect cross-modal non-spatial repetition inhibition

The present study examined the effect of different latencies for processing visual and auditory stimuli in cross-modal non-spatial repetition inhibition. In two experiments, the cue validity of modality and identity between the prime and the target was manipulated in a "prime-neutral cue-target" paradigm. A distinct neutral event was presented after the prime and before the onset of the target. The prime probe was visual in Experiment 1 and auditory in Experiment 2. The results in both experiments showed that RTs for identity-cued trials were significantly slower than RTs for identity-cued trials regardless of whether the modality of the target was visual or auditory. In addition, RTs for visual trials were significantly faster than RTs for auditory trials, indicating different latencies of processing visual and auditory stimuli. This latency difference affects cross-modal non-spatial repetition inhibition in two aspects: 1) creating a new representation (identity uncued) that is delivered via visual modality is easier under audio-visual conditions, and 2) retrieving an inhibited representation (identity cued) that is delivered via auditory modality is more difficult under visual-audio conditions. We propose that cross-modal non-spatial repetition inhibition, which is distinct from unimodal repetition inhibition, can be easily influenced by different latencies of processing visual and auditory stimuli.

The influence of relevant and irrelevant stereoscopic depth cues: Depth information does not always capture attention

Previous research reported ambiguous findings regarding the relationship of visuospatial attention and (stereoscopic) depth information. Some studies indicate that attention can be focused on a distinct depth plane, while other investigations revealed attentional capture from irrelevant items located in other, unattended depth planes. To evaluate whether task relevance of depth information modulates the deployment of attentional resources across depth planes, the additional singleton paradigm was adapted: Singletons defined by depth (i.e., displayed behind or in front of a central depth plane) or color (green against gray) were presented among neutral items and served as targets or (irrelevant) distractors. When participants were instructed to search for a color target, no attentional capture from irrelevant depth distractors was observed. In contrast, it took substantially longer to search for depth targets when an irrelevant distractor was presented simultaneously. Color distractors as well as depth distractors caused attentional capture, independent of the distractors' relative depth position (i.e., in front of or behind the target). However, slight differences in task performance were obtained depending on whether or not participants fixated within the target depth plane. Thus, the current findings indicate that attentional resources in general are uniformly distributed across different depth planes. Although task relevant depth singletons clearly affect the attentional system, this information might be processed subsequent to other stimulus features.

Fast and Forceful: Modulation of Response Activation Induced by Shifts of Perceived Depth in Virtual 3D Space

Reaction time (RT) can strongly be influenced by a number of stimulus properties. For instance, there was converging evidence that perceived size rather than physical (i.e., retinal) size constitutes a major determinant of RT. However, this view has recently been challenged since within a virtual three-dimensional (3D) environment retinal size modulation failed to influence RT. In order to further investigate this issue in the present experiments response force (RF) was recorded as a supplemental measure of response activation in simple reaction tasks. In two separate experiments participants' task was to react as fast as possible to the occurrence of a target located close to the observer or farther away while the offset between target locations was increased from Experiment 1 to Experiment 2. At the same time perceived target size (by varying the retinal size across depth planes) and target type (sphere vs. soccer ball) were modulated. Both experiments revealed faster and more forceful reactions when targets were presented closer to the observers. Perceived size and target type barely affected RT and RF in Experiment 1 but differentially affected both variables in Experiment 2. Thus, the present findings emphasize the usefulness of RF as a supplement to conventional RT measurement. On a behavioral level the results confirm that (at least) within virtual 3D space perceived object size neither strongly influences RT nor RF. Rather the relative position within egocentric (body-centered) space presumably indicates an object's behavioral relevance and consequently constitutes an important modulator of visual processing.