Environmental Reference Frame Research Articles

Cardinal direction judgment based on the integration of spatial reference frames in different languages

Abstract This study investigates how integrated egocentric and environmental reference frames influence direction determination and cardinal direction judgments in L1 speakers of Mongolian and Mandarin. The results show that in direction determination, Mandarin participants’ integrated frame of reference is “front-north, back-south, left-west, and right-east.” By contrast, Mongolian participants use two modes of integrated spatial representation: “front-south, back-north, left-east, and right-west” and “front-north, back-south, left-west, and right-east”. This behavior points to influences from the participants’ dominant and non-dominant languages. Mongolian and Mandarin participants showed a north advantage in cardinal direction judgment tasks with a “front-north” response configuration. Whereas Mandarin participants consistently showed a north advantage effect, Mongolian participants showed a south advantage effect in the “front-south” configuration. This suggests that in addition to the long-recognized difference in north-south/east-west axis preference, a north-south axis specification where south was the normative direction instead of north can result from cultural and linguistic influence. The results corroborate the idea that language affects the integration of spatial reference frames, lending support to linguistic relativism.

Things are looking up: Vertical eye gaze in the environment affects perceptions of emotional valence in sad faces.

Successful social interactions depend on the ability to quickly evaluate emotional facial expressions. Research has shown that head orientation and eye gaze are informative affective signals. Across four experiments, we explored a novel eye-gaze cue grounded in a consideration of English spatial metaphors, where up connotes positive feelings ("I'm flying high") and down connotes negative feelings ("I'm feeling low"). Participants either rated the valence of or categorised a set of sad and happy faces gazing in different directions along the vertical axis. We expected to find a spatial-valence congruency effect, where valence ratings and reaction times would be moderated by whether or not the face was gazing in a metaphor-consistent direction. The results partially supported this hypothesis: sad faces gazing upwards (as opposed to downwards) were rated as happier or more positive (Experiments 1 and 2) and classified slower (Experiments 3 and 4). This was true whether the looking direction was cued by eye gaze in front-view faces (Experiment 1) or by the orientation of profile faces (Experiments 2-4). In addition, this spatial-valence congruency effect was only reliable in the environmental frame of reference (Experiment 4). We found little evidence for a comparable effect of gaze direction on judgements of happy faces, suggesting that eye gaze along the vertical axis may differentially affect judgements of approach and avoidance-related emotional expressions. This has implications for the inferences scholars draw about underlying cognitive representations from observations of conventional metaphorical language.

Roles of the Retinotopic and Environmental Frames of Reference on Vection

Humans perceive self-motion using multisensory information, while vision has a dominant role as is utilized in virtual reality (VR) technologies. Previous studies reported that visual motion presented in the lower visual field (LoVF) induces stronger illusion of self-motion (vection) as compared with the upper visual field (UVF). However, it was still unknown whether the LoVF superiority in vection was based on the retinotopic frame, or rather related to the environmental frame of reference. Here, we investigated the influences of retinotopic and environmental frames on the LoVF superiority of vection. We presented a planer surface along the depth axis in one of four visual fields (upper, lower, right, or left). The texture on the surface moved forward or backward. Participants reported vection while observing the visual stimulus through a VR head mounted display (HMD) in the sitting posture or lateral recumbent position. Results showed that the visual motion induced stronger vection when presented in the LoVF compared with the UVF in both postures. Notably, the vection rating in LoVF was stronger in the sitting than in the recumbent. Moreover, recumbent participants reported stronger vection when the stimulus was presented in the gravitationally lower field than in the gravitationally upper field. These results demonstrate contribution of multiple spatial frames on self-motion perception and imply the importance of ground surface.

Reading sideways: Effects of egocentric and environmental orientation in a lexical decision task

Many image-level factors affect reading speed and comprehension, including the in-plane orientation of text. As words’ angular deviation from upright increases, so do response times. Here we investigated whether these orientation effects in reading are based purely on an egocentric (retinal) reference frame, or whether there is also a contribution of the environmental reference frame. Participants completed a lexical decision task with six-letter, two-syllable words and nonwords presented at a wide range of angles, in increments of 22.5°. A control group of participants (N = 66) completed the task while sitting upright, and an experimental group (N = 43) completed the task while lying sideways on their right side. The function relating the egocentric orientation of strings to response times was symmetric for upright observers, but skewed for observers who lay sideways, with an advantage for responding to environmentally upright text. Our results suggest that sideways readers may use an oblique reference frame (similar to the perceptual upright) for mentally rotating text. We discuss implications for designing optimal text orientations in head mounted displays.

The influence of visual and vestibular orientation cues in a clock reading task.

We investigated how performance in the real-life perceptual task of analog clock reading is influenced by the clock's orientation with respect to egocentric, gravitational, and visual-environmental reference frames. In Experiment 1, we designed a simple clock-reading task and found that observers' reaction time to correctly tell the time depends systematically on the clock's orientation. In Experiment 2, we dissociated egocentric from environmental reference frames by having participants sit upright or lie sideways while performing the task. We found that both reference frames substantially contribute to response times in this task. In Experiment 3, we placed upright or rotated participants in an upright or rotated immersive virtual environment, which allowed us to further dissociate vestibular from visual cues to the environmental reference frame. We found evidence of environmental reference frame effects only when visual and vestibular cues were aligned. We discuss the implications for the design of remote and head-mounted displays.

Representing Spatial Layout According to Intrinsic Frames of Reference: Limitations From Position Regularity and Instructions.

Mou and McNamara have suggested that object locations are represented according to intrinsic reference frames. In three experiments, we investigated the limitations of intrinsic reference frames as a mean to represent object locations in spatial memory. Participants learned the locations of seven or eight common objects in a rectangular room and then made judgments of relative direction based on their memory of the layout. The results of all experiments showed that when all objects were positioned regularly, judgments of relative direction were faster or more accurate for novel headings that were aligned with the primary intrinsic structure than for other novel headings; however, when one irregularly positioned object was added to the layout, this advantage was eliminated. The experiments further indicated that with a single view at study, participants could represent the layout from either an egocentric orientation or a different orientation, according to experimental instructions. Together, these results suggest that environmental reference frames and intrinsic axes can influence performance for novel headings, but their role in spatial memory depends on egocentric experience, layout regularity, and instructions.

Representation of Gravity-Aligned Scene Structure in Ventral Pathway Visual Cortex

The ventral visual pathway in humans and non-human primates is known to represent object information, including shape and identity [1]. Here, we show the ventral pathway also represents scene structure aligned with the gravitational reference frame in which objects move and interact. We analyzed shape tuning of recently described macaque monkey ventral pathway neurons that prefer scene-like stimuli to objects [2]. Individual neurons did not respond to a single shape class, but to a variety of scene elements that are typically aligned with gravity: large planes in the orientation range of ground surfaces under natural viewing conditions, planes in the orientation range of ceilings, and extended convex and concave edges in the orientation range of wall/floor/ceiling junctions. For a given neuron, these elements tended to share a common alignment in eye-centered coordinates. Thus, each neuron integrated information about multiple gravity-aligned structures as they would be seen from a specific eye and head orientation. This eclectic coding strategy provides only ambiguous information about individual structures but explicit information about the environmental reference frame and the orientation of gravity in egocentric coordinates. In the ventral pathway, this could support perceiving and/or predicting physical events involving objects subject to gravity, recognizing object attributes like animacy based on movement not caused by gravity, and/or stabilizing perception of the world against changes in head orientation [3-5]. Our results, like the recent discovery of object weight representation [6], imply that the ventral pathway is involved not just in recognition, but also in physical understanding of objects and scenes.

D’Alembert’s Direct and Inertial Forces Acting on Populations: The Price Equation and the Fundamental Theorem of Natural Selection

I develop a framework for interpreting the forces that act on any population described by frequencies. The conservation of total frequency, or total probability, shapes the characteristics of force. I begin with Fisher’s fundamental theorem of natural selection. That theorem partitions the total evolutionary change of a population into two components. The first component is the partial change caused by the direct force of natural selection, holding constant all aspects of the environment. The second component is the partial change caused by the changing environment. I demonstrate that Fisher’s partition of total change into the direct force of selection and the forces from the changing environmental frame of reference is identical to d’Alembert’s principle of mechanics, which separates the work done by the direct forces from the work done by the inertial forces associated with the changing frame of reference. In d’Alembert’s principle, there exist inertial forces from a change in the frame of reference that exactly balance the direct forces. I show that the conservation of total probability strongly shapes the form of the balance between the direct and inertial forces. I then use the strong results for conserved probability to obtain general results for the change in any system quantity, such as biological fitness or energy. Those general results derive from simple coordinate changes between frequencies and system quantities. Ultimately, d’Alembert’s separation of direct and inertial forces provides deep conceptual insight into the interpretation of forces and the unification of disparate fields of study.

Exploring green criminology: toward a green criminological revolution

Few criminologists have drawn attention to the fact that widespread and significant forms of harm such as green or environmental crimes are neglected by criminology. Others have suggested that green crimes present the most important challenge to criminology as a discipline. This book argues that criminology needs to take green harms more seriously and to be revolutionized so that it forms part of the solution to the large environmental problems currently faced across the word. It asks how criminology should be redesigned to consider green/environmental harm as a key area of study in an era where destruction of the earth and the world’s ecosystem is a major concern and examines why this has remained unaccomplished so far. The chapters in this book apply an environmental frame of reference underlying a green approach to issues which can be addressed from within criminology and which can encourage criminologists and environmentalists to respond and react differently to environmental crime.

Insights from introspection: a commentary on Gould et al. (2014), "An extended case study on the phenomenology of spatial form synaesthesia".

Insights from introspection: a commentary on Gould et al. (2014), "An extended case study on the phenomenology of spatial form synaesthesia".

Visual attention to reference frames affects perceptions of shape from shading.

Perception of shape from shading is processed locally in a bottom-up manner, but is also influenced by global or contextual factors. This study examined the influence of attention to the reference frame on the perception of shape from shading. In a visual search task, participants were asked to identify the location of a target relative to the reference frame. The results showed that shaded targets were more quickly and accurately detected when the shading gradient was parallel, rather than orthogonal, to the orientation of the environmental reference frame. This was further supported by a second experiment with a masking paradigm. Consequently, the perceptual process of shape from shading may be a flexible mechanism in which the representation of gradient orientation is calibrated by top-down processing in visual attention.

Integration of visuospatial information encoded from different viewpoints

Two experiments investigated whether separate sets of objects viewed in the same environment but from different views were encoded as a single integrated representation or maintained as distinct representations. Participants viewed two circular layouts of objects that were placed around them in a round (Experiment 1) or a square (Experiment 2) room and were later tested on perspective-taking trials requiring retrieval of either one layout (within-layout trials) or both layouts (between-layout trials). Results from Experiment 1 indicated that participants did not integrate the two layouts into a single representation. Imagined perspective taking was more efficient on within- than on between-layout trials. Furthermore, performance for within-layout trials was best from the perspective that each layout was studied. Results from Experiment 2 indicated that the stable environmental reference frame provided by the square room caused many, but not all, participants to integrate all locations within a common representation. Participants who integrated performed equally well for within-layout and between-layout judgments and also represented both layouts using a common reference frame. Overall, these findings highlight the flexibility of organizing information in spatial memory.

Selective role of lingual/parahippocampal gyrus and retrosplenial complex in spatial memory across viewpoint changes relative to the environmental reference frame

Remembering object locations across different views is a fundamental competence for keeping oriented in large-scale space. Here we investigated such ability by comparing encoding and retrieval of locations across viewpoint changes relative to different spatial frames of reference. We acquired functional magnetic resonance images while subjects detected target displacements across consecutive views of a familiar virtual room, reporting changes in the target absolute position in the room (stable environmental frame), changes in its position relative to a set of movable objects (unstable object-based frame), and changes relative to their point of view (control viewer-centered frame). Behavioral costs were higher for the stable environmental frame, and a cortical network including the lingual/parahippocampal gyrus (LPHG) and the retrosplenial complex (RSC) selectively encoded spatial locations relative to this frame. Several regions, including the dorsal fronto-parietal cortex and the LPHG, were modulated by the amount of experienced viewpoint change, but only the RSC was selectively modulated by the amount of viewpoint change relative to the environmental frame, thus showing a special role in coding one's own position and heading in familiar environments.

Beyond the retina: Evidence for a face inversion effect in the environmental reference frame

Beyond the retina: Evidence for a face inversion effect in the environmental reference frame

Frames of reference for biological motion and face perception

We investigated the roles of egocentric, gravitational, and visual environmental reference frames for face and biological motion perception. We tested observers on face and biological motion tasks while orienting the visual environment and the observer independently with respect to gravity using the York Tumbling Room. The relative contribution of each reference frame was assessed by arranging pairs of frames to be either aligned or opposed to each other while rendering the third uninformative by orienting it sideways relative to the stimulus. The perception of both biological motion and faces were optimal when the stimulus was aligned with egocentric coordinates. However, when the egocentric reference frame was rendered uninformative, the perception of biological motion, but not faces, relied more on stimulus alignment with gravity rather than the visual environment.

Frame of Reference in the Mental Representation of Objects Layout

Frame of Reference in the Mental Representation of Objects Layout

Changes in frame of reference use across the preschool years: A longitudinal study of the gestures and speech produced during route descriptions

This study longitudinally investigated developmental changes in the frame of reference used by children in their gestures and speech. Fifteen children, between 4 and 6 years of age, were asked once a year to describe their route home from their nursery school. When the children were 4 years old, they tended to produce gestures that directly and continuously indicated their actual route in a large gesture space. In contrast, as 6-year-olds, their gestures were segmented and did not match the actual route. Instead, at age 6, the children seemed to create a virtual space in front of themselves to symbolically describe their route. These results indicate that the use of frames of reference develops across the preschool years, shifting from an actual environmental to an abstract environmental frame of reference. Factors underlying the development of frame of reference, including verbal encoding skills and experience, are discussed.

Location memory biases reveal the challenges of coordinating visual and kinesthetic reference frames

Five experiments explored the influence of visual and kinesthetic/proprioceptive reference frames on location memory. Experiments 1 and 2 compared visual and kinesthetic reference frames in a memory task using visually-specified locations and a visually-guided response. When the environment was visible, results replicated previous findings of biases away from the midline symmetry axis of the task space, with stability for targets aligned with this axis. When the environment was not visible, results showed some evidence of bias away from a kinesthetically-specified midline (trunk anterior-posterior [a-p] axis), but there was little evidence of stability when targets were aligned with body midline. This lack of stability may reflect the challenges of coordinating visual and kinesthetic information in the absence of an environmental reference frame. Thus, Experiments 3-5 examined kinesthetic guidance of hand movement to kinesthetically-defined targets. Performance in these experiments was generally accurate with no evidence of consistent biases away from the trunk a-p axis. We discuss these results in the context of the challenges of coordinating reference frames within versus between multiple sensori-motor systems.

Frame of reference for visual perception in young infants during change of body position

The visual and vestibular systems begin functioning early in life. However, it is unclear whether young infants perceive the dynamic world based on the retinal coordinate (egocentric reference frame) or the environmental coordinate (allocentric reference frame) when they encounter incongruence between frames of reference due to changes in body position. In this study, we performed the habituation-dishabituation procedure to assess novelty detection in a visual display, and a change in body position was included between the habituation and dishabituation phases in order to test whether infants dishabituate to the change in stimulus on the retinal or environmental coordinate. Twenty infants aged 3-4 months were placed in the right-side-down position (RSDp) and habituated to an animated human-like character that walked horizontally in the environmental frame of reference. Subsequently, their body position was changed in the roll plane. Ten infants were repositioned to the upright position (UPp) and the rest, to the RSDp after rotation. In the test phase, the displays that were spatially identical to those shown in the habituation phase and 90 degrees rotated displays were alternately presented, and visual preference was examined. The results revealed that infants looked longer at changes in the display on the retinal coordinate than at changes in the display on the environmental coordinate. This suggests that changes in body position from lying to upright produced incongruence of the egocentric and allocentric reference frames for perception of dynamic visual displays and that infants may rely more on the egocentric reference frame.

Modulation of neural activity by angle of rotation during imagined spatial transformations

Imagined spatial transformations of objects (e.g., mental rotation) and the self (e.g., perspective taking) are psychologically dissociable. In mental rotation, the viewer transforms the location or orientation of an object relative to stable egocentric and environmental reference frames. In imagined shifts of perspective, the viewer's egocentric reference frame is transformed with respect to stable objects and environment. Using fMRI, we showed that during mental transformations of objects the right superior parietal cortex exhibited a positive linear relationship between hemodynamic response and degrees of rotation. By contrast, during imagined transformations of the self, the same regions exhibited a negative linear trend. We interpret this finding in terms of the role of parietal cortex in coding the locations of objects in relation to the body.