Lateral spatial biases in naturalistic and simulated driving: Does pseudoneglect influence performance?

Whereas a rightward bump is more likely than a leftward bump when walking through a doorway, investigations into potential similar asymmetries for drivers are limited. The research presented here aims to determine the influence of innate lateral spatial biases when driving. Data from the Strategic Highway Research Program Naturalistic Driving Study (SHRP 2 NDS) and a driving simulation were used to address our research questions. Data points from SHRP 2 were aggregated within relevant variables (e.g., left/right obstacles). In the simulation, participants drove in ways that were consistent with their everyday driving in urban and rural environments. Collision frequency, collision severity and average lateral lane position were analyzed with rightward biases throughout both analyzes. SHRP 2 data indicated greater likelihoods of collisions when vehicles crossed the right line/edge of the road and when making a right turn. There were more collisions with obstacles on the right side, which were also more severe, and greater rightward lane deviations in the driving simulation, contrasted with more severe collisions on the left side in SHRP 2 data, possibly because of the presence of traffic. These findings suggest that previously observed rightward biases in distant space when walking are also present when driving.

Evidence for abnormal visuospatial attentional processes in the interictal migraineur.

Research shows decreased brain region activity in the right temporo-parietal junction (rTPJ) in people with migraine headache relative to headache-free controls when performing an orienting visuospatial attention task. Functional inactivation of the rTPJ has been associated with rightward performance deviations on laterality-based attention Landmark (LM) and greyscale (GRE) tasks in individuals with unilateral neglect and heightened activation in the rTPJ is associated with leftward deviation, known as pseudoneglect, in controls on these tasks. Given this, we investigated whether migraineurs would lack the leftward deviation found in headache-free controls on visuospatial attention tasks. 36 migraineurs and 38 controls were presented with LM and GRE tasks. Response bias scores showed a significant difference in responses between groups (p = 0.036) on the GRE, a luminance-based task, but not on the LM, a size-based task (p = 0.826). This study is the first to show laterality-based attentional differences in migraineurs, as compared to controls. Specifically, migraineurs were found to have smaller leftward biases on luminance-based visuospatial attention tasks, as compared to controls, aligning with previous research suggesting that migraine may be having an impact on a variety of attention tasks in migraineurs in between headache attacks.

Lateral biases in aesthetic and spatial location judgments: differences between tasks and native reading directions.

People exhibit consistent leftward spatial biases across a variety of tasks. However, individuals with a native reading direction other than left-to-right (LTR) show an attenuation of the leftward bias. The current study used procedurally similar tasks to examine spatial ability and aesthetic preferences in LTR and right-to-left (RTL) groups. In the spatial task participants viewed a centred rectangle partially occluded by an overlapping circle and estimated the centre of the circle with a single mouse click. In the aesthetic task participants used the mouse to control a "virtual flashlight" to light images of abstract paintings in the most aesthetically pleasing way. Contrary to predictions, smaller errors were made for circles on the right and estimations were progressively less accurate as circle size increased in the spatial task. On the aesthetic task, light placements of LTR participants were biased to the left and significantly different from the slightly rightward placements of RTL participants. As predicted, when completing the aesthetics task amounts of time scanning left or right visual space were different between groups. Findings support the theory that directional scanning biases attenuate leftward lateral biases and further, the nature of the visuospatial task may vary the strength of lateral bias.

Overestimation of self-reported driving exposure: Results from the SHRP2 Naturalistic Driving Study.

OBJECTIVES: The accuracy of self-reported driving exposure has questioned the validity of using self-reported mileage to inform research questions. Studies examining the accuracy of self-reported driving exposure compared to objective measures find low validity, with drivers overestimating and underestimating driving distance. The aims of the current study were to (1) examine the discrepancy between self-reported annual mileage and driving exposure the following year and (2) investigate whether these differences depended on age and annual mileage. METHODS: Two estimates of drivers' self-reported annual mileage collected during vehicle installation (obtained via prestudy questionnaires) and approximated annual mileage driven (based upon Global Positioning System data) were acquired from 3,323 participants who participated in the Strategic Highway Research Program 2 (SHRP2) Naturalistic Driving Study. RESULTS: A Wilcoxon signed rank test showed that there was a significant difference between self-reported and annual driving exposure during participation in SHRP 2, with the majority of self-reported responses overestimating annual mileage the following year, irrespective of whether an ordinal or ratio variable was examined. Over 15% of participants provided self-reported responses with over 100% deviation, which were exclusive to participants underestimating annual mileage. Further, deviations in reporting differed between participants who had low, medium, and high exposure, as well as between participants in different age groups. CONCLUSIONS: These findings indicate that although self-reported annual mileage is heavily relied on for research, such estimates of driving distance may be an overestimate of current or future mileage and can influence the validity of prior research that has utilized estimates of driving exposure.

The Trajectory of Pseudoneglect in Adults: A Systematic Review.

Neurologically healthy adults tend to display a reliable leftward perceptual bias during visuospatial tasks, a phenomenon known as pseudoneglect. However, the phenomenon in older adults is not well understood, and a synthesis of research that examines pseudoneglect using the line bisection task, as well as other tasks, in the context of aging is lacking. The aim of the current systematic review is to integrate the available research on pseudoneglect in late adulthood, and to discuss the association between age and a bias to the left hemispace. The systematic search revealed that five different tasks have been used to examine pseudoneglect in younger and older adults, and that participants over 60 years of age have demonstrated inconsistent perceptual biases (e.g., enhanced leftward bias, suppressed leftward bias, and rightward bias). Based on current evidence, although some age-related trends in the perceptual bias can be identified within each task, no firm conclusions about the effects of age on pseudoneglect can be drawn. A number of recommendations for future research are outlined throughout the review, including use of smaller age ranges within age groups, differentiating between neurologically healthy participants and those with clinical diagnoses, continued examination of gender, and consistent use of stimuli and methods of analyses within each task to improve internal comparability.

Left wings to the left: Posing and perceived political orientation.

Images of individuals posing with the left cheek toward the camera are rated as more emotionally expressive than images with the right cheek toward the camera, which is theorized to be due to right hemisphere specialization for emotion processing. Liberals are stereotyped as being more emotional than conservatives. In the present study, we presented images of people displaying either leftward or rightward posing biases in an online task, and asked participants to rate people's perceived political orientation. Participants rated individuals portrayed with a leftward posing bias as significantly more liberal than those presented with a rightward bias. These findings support the idea that posing direction is related to perceived emotionality of an individual, and that liberals are stereotyped as more emotional than conservatives. Our results differ from those of a previous study, which found conservative politicians are more often portrayed with a leftward posing bias, suggesting differences between posing output for political parties and perceived political orientation. Future research should investigate this effect in other countries, and the effect of posing bias on perceptions of politicians.

Presenting Your Best Self(ie): The Influence of Gender on Vertical Orientation of Selfies on Tinder.

When taking a self-portrait or "selfie" to display in an online dating profile, individuals may intuitively manipulate the vertical camera angle to embody how they want to be perceived by the opposite sex. Concepts from evolutionary psychology and grounded cognition suggest that this manipulation can provide cues of physical height and impressions of power to the viewer which are qualities found to influence mate-selection. We predicted that men would orient selfies more often from below to appear taller (i.e., more powerful) than the viewer, and women, from an above perspective to appear shorter (i.e., less powerful). A content analysis was conducted which coded the vertical orientation of 557 selfies from profile pictures on the popular mobile dating application, Tinder. In general, selfies were commonly used by both men (54%) and women (90%). Consistent with our predictions, a gender difference emerged; men's selfies were angled significantly more often from below, whereas women's were angled more often from above. Our findings suggest that selfies presented in a mate-attraction context are intuitively or perhaps consciously selected to adhere to ideal mate qualities. Further discussion proposes that biological or individual differences may also facilitate vertical compositions of selfies.

Crashing Left vs. Right: Examining Navigation Asymmetries Using the SHRP2 Naturalistic Driving Study Data.

The magnitude of leftward bias demonstrated in pseudoneglect has been found to differ between younger and older adults in laboratory settings. The objective of this study was to examine the association between age and asymmetries in navigation in a naturalistic setting by examining the frequency of the location of impact on participants' vehicles during crashes and near crashes. The location of impact following crashes and near crashes, and participant's age and gender were retrieved from the SHRP2 NDS database, a large scale naturalistic driving study. Over the course of the study, data were collected from 3,546 participants driving in the United States of America (right-side traffic directionality), which included 1,465 crashes and 2,722 near crashes. During crashes and near crashes, irrespective of age, the location impact was most often on the front side of the participant vehicle. In contrast with results from laboratory environments, age was not associated with the location of impact during crashes and near crashes, and overall, crashes were over-represented on the left side of the vehicle compared to the right. Specifically, crashes were 1.41 times as likely to occur on the left compared to the right side of participants' vehicles. Overall, these findings inform future research that attempts to apply laboratory research, regarding asymmetry in navigation, to naturalistic settings.

Developmental trajectory of pseudoneglect in adults using the greyscales task.

Neurologically healthy adults display a reliable but slight leftward spatial bias, and this bias appears to change with age (Jewell & McCourt, 2000). Studies using line bisection and the landmark task to investigate pseudoneglect in participants over 60 years of age have shown suppression and near reversal of the leftward response bias. The current research investigates the developmental trajectory of perceptual biases using the greyscales task-a task that exhibits strengths compared to the line bisection and landmark task, as it generates a stronger and more consistent bias. Participants ranging from 18 to 88 years of age viewed 40 asymmetrical equiluminant gradient pairs with each stimulus appearing darker on the left and right side. Overall, a negative correlation was found between a leftward response bias and age, r(492) = -.154, p < .001, with the oldest age group (80-89 year olds) exhibiting a significantly stronger leftward bias compared to youngest age group (18-29 year olds), p = .016. These findings are in contrast with previous research proposing a reduced bias in perceptual attention among older adults, and suggest that further research is needed to understand the reliability of age-related changes in spatial attention. The findings also contribute to the understanding of developmental changes in allocation of spatial attention over the adult life span. (PsycINFO Database Record

Family matters: Directionality of turning bias while kissing is modulated by context.

When leaning forward to kiss to a romantic partner, individuals tend to direct their kiss to the right more often than the left. Studies have consistently demonstrated this kissing asymmetry, although other factors known to influence lateral biases, such as sex or situational context, had yet to be explored. The primary purpose of our study was to investigate if turning direction was consistent between a romantic (parent-parent) and parental (parent-child) kissing context, and secondly, to examine if sex differences influenced turning bias between parent-child kissing partners. An archival analysis coded the direction of turning bias for 161 images of romantic kissing (mothers kissing fathers) and 529 images of parental kissing (mothers or fathers kissing sons or daughters). The results indicated that the direction of turning bias differed between kissing contexts. As expected, a right-turn bias was observed for romantic kissing; however, a left-turn bias was exhibited for parental kissing. There was no significant difference of turning bias between any parent-child kissing partners. Interpretations for the left-turn bias discuss parental kissing as a learned lateral behaviour.

Did Buddha turn the other cheek too? A comparison of posing biases between Jesus and Buddha.

People tend to exhibit a leftward bias in posing. Various studies suggest that posing to the left portrays a stronger emotion, whereas posing to the right portrays a more neutral emotion. Religions such as Christianity emphasize the role of strong emotions in religious experience, whereas religions such as Buddhism emphasize the calming of emotions as being important. In the present study, we investigated if the emphasis on emotionality of a religion influences the depiction of their religious figures. Specifically, we coded 484 paintings of Jesus and Buddha from online art databases for whether the deity exhibited a left bias, right bias, or central face presentation. The posing biases were analysed to discover whether paintings of Jesus would more frequently depict a leftward bias than paintings of Buddha. Jesus is more commonly depicted with a leftward bias than Buddha, and Buddha is more commonly depicted with a central face presentation than Jesus. These findings support the idea that the amount of emotionality that is to be conveyed in artwork influences the whether the subject is posed with a leftward bias.

Take your seats: leftward asymmetry in classroom seating choice.

Despite an overall body symmetry, human behavior is full of examples of asymmetry, from writing or gesturing to kissing and cradling. Prior research has revealed that theatre patrons show a bias towards sitting on the right side of a movie theatre. Two competing theories have attempted to explain this seating asymmetry: one posits that expectation of processing demand drives the bias; the other posits that basic motor asymmetries drive the bias. To test these theories we assessed the real-world classroom seating choices of university students using photographs. A bias for students to choose seats on the left side of the classroom was observed, in contrast to the right side bias observed in theatre seating studies. These results provide evidence in support of a processing-expectation bias.

The thinker: opposing directionality of lighting bias within sculptural artwork.

Individuals tend to perceive the direction of light to come from above and slightly from the left; it has been speculated that this phenomenon is also producing similar lighting preferences within 2-dimensional artworks (e.g., paintings, advertisements). The purpose of the present study was to address if lighting bias was present in the 3-dimensional medium of sculpture by implementing a virtual art gallery lighting paradigm. Thirty-nine participants completed a computer task that consisted of 48 galleries each containing one sculpture (24 original sculptures, 24 mirror-reversed) which was surrounded by eight lights (above/below, left/right, front/back). Participants would select one light source to illuminate the sculpture in a manner they perceived to be the most aesthetically pleasing. The results indicated a significant preference for lights positioned from above and from the right, a finding that is contradictory to previous lighting bias research examining artworks. An interpretation for the rightward bias applies the perceptual concept of subjective lighting equality. Objects illuminated from the left typically appear brighter in comparison to right-side lighting; in sculpture, however, increased luminosity can reduce the sculptural detail, and may have been compensated via right-side lighting choices within the lighting task.

Native reading direction influences lateral biases in the perception of shape from shading.

Although neurologically normal individuals often exhibit leftward biases of perception and attention, known as pseudoneglect, factors such as lighting, spatial location and native reading direction have been found to modulate these biases. To investigate lighting and spatial biases in left-to-right and right-to-left readers search times were measured in a target finding task where lighting and target locations were manipulated. Target search times under upper-left lighting were significantly shorter than lower-left, upper-right and lower-right lighting among left-to-right readers. Right-to-left readers did not display the same leftward bias, even displaying significantly shorter search times under upper-right lighting than those of left-to-right readers. Significantly shorter search times for targets located in the upper-left quadrant (compared to other quadrants) were observed for left-to-right readers, while search times for upper-right located targets were significantly shorter for right-to-left readers compared to those of left-to-right readers. Participant scan times of stimuli divided into equal quadrants were monitored by an eye-tracking camera. Both groups displayed greater scan times in upper quadrants. These findings suggest that native reading direction modulates spatial and light perception biases resulting in weaker leftward, or a lack of lateral biases among right-to-left readers.

Behavioural asymmetries on the greyscales task: The influence of native reading direction.

Reliable leftward attentional and perceptual biases demonstrated in a variety of visuospatial tasks have been found to deviate from the left in research examining the influence of scanning habits. The aim of the current research was to examine the influence of native script direction on pseudoneglect during the greyscales task in a representative sample of native right-to-left readers. Fifty-four native left-to-right readers and 43 right-to-left readers completed the greyscales task, which required judging the darker of two left-right mirrored brightness gradients. Native left-to-right readers demonstrated a left response bias on the greyscales task, whereas right-to-left readers failed to demonstrate a bias, however, both groups responded more quickly when making leftward choices. The research suggests that the strength of attentional biases are influenced by behavioural biases, such as scanning habits, and neural and anatomical asymmetries in the right parietal and frontal cortices. Thus, to improve the clinical utility of the greyscales task for diagnosing neglect, right-to-left readers should be examined to fully understand the normal range of biases displayed by neurologically healthy individuals.

Lower-right and upper-left biases within upper and lower visual fields in a circular array task.

Visuospatial performance varies along the horizontal and vertical dimensions, resulting in behavioral biases such as pseudoneglect. The interaction between the horizontal and vertical attentional biases was investigated using a novel circular array task capable of conveying relative brightness information across vertical and horizontal dimensions simultaneously. In a novel circular array task comprised of six discs, the grayscale gradient was disrupted by switching two grayscale values within the array. Leftward biases were observed in the lower visual fields and rightward biases in the upper visual fields. More importantly, the magnitude of bias within the upper/lower horizontal dimension altered depending on the relative position of the stimuli along horizontal and vertical axes within each dimension. Manipulating the upper-most and leftward discs yield stronger biases than manipulating rightward discs. Furthermore, stronger biases were observed during bottom and rightward disc manipulation. The upper-left and lower-right biases within the horizontal dimension indicate that the interactions between the horizontal and vertical biases may not rely simply on the dichotomy within the horizontal and vertical dimensions, but also on the relative spatial distribution of stimuli within these dimensions.

Dynamic stimuli: accentuating aesthetic preference biases.

Despite humans' preference for symmetry, artwork often portrays asymmetrical characteristics that influence the viewer's aesthetic preference for the image. When presented with asymmetrical images, aesthetic preference is often given to images whose content flows from left-to-right and whose mass is located on the right of the image. Cerebral lateralization has been suggested to account for the left-to-right directionality bias; however, the influence of cultural factors, such as scanning habits, on aesthetic preference biases is debated. The current research investigates aesthetic preference for mobile objects and landscapes, as previous research has found contrasting preference for the two image types. Additionally, the current experiment examines the effects of dynamic movement on directionality preference to test the assumption that static images are perceived as aesthetically equivalent to dynamic images. After viewing mirror-imaged pairs of pictures and videos, right-to-left readers failed to show a preference bias, whereas left-to-right readers preferred stimuli with left-to-right directionality regardless of the location of the mass. The directionality bias in both reading groups was accentuated by the videos, but the bias was significantly stronger in left-to-right readers. The findings suggest that scanning habits moderate the leftward bias resulting from hemispheric specialization and that dynamic stimuli further fluent visual processing.

Lateral bias in theatre-seat choice.

Examples of behavioural asymmetries are common in the range of human behaviour; even when faced with a symmetrical environment people demonstrate reliable asymmetries in behaviours like gesturing, cradling, and even seating. One such asymmetry is the observation that participants tend to choose seats to the right of the screen when asked to select their preferred seating location in a movie theatre. However, these results are based on seat selection using a seating chart rather than examining real seat choice behaviour in the theatre context. This study investigated the real-world seating patterns of theatre patrons during actual film screenings. Analysis of bias scores calculated using photographs of theatre patrons revealed a significant bias to choose seats on the right side of the theatre. These findings are consistent with the prior research in the area and confirm that the seating bias observed when seats are selected from a chart accurately reflects real-world seating behaviour.

Native reading direction and corresponding preferences for left- or right-lit images.

The first language an individual learns has been shown to influence performance on cognitive tasks. Individuals who first learn to read and write in a left-to-right direction (native left-to-right readers) tend to bisect lines left of centre and draw counterclockwise circles, whereas those who learn to read and write from right-to-left (native right-to-left readers) will bisect lines closer to the objective centre and draw circles in a clockwise direction. The aim of the current study was to assess group differences in image preferences and eye movements when participants are simultaneously presented with an original and mirror image with an obvious illumination difference. Twenty native left-to-right readers (4 men, 16 women) and 25 native right-to-left readers (13 men, 12 women) participated. Left-to-right readers made more fixations on the left side of images and exhibited a significantly different left-lit image bias than right-to-left readers' choices. These results draw attention to the influence that reading direction has on scanning distributions and lighting preferences, and question previous results finding no difference between groups.

Dorsal stream contributions to perceptual asymmetries.

Neurologically normal individuals show a bias toward the left side of space, referred to as pseudoneglect due to its similarity to clinical hemispatial neglect. The left bias appears to be stronger in the lower visual field during free-viewing, which could result from preferential dorsal stream processing. The current experiments used modified greyscales tasks, incorporating motion and isoluminant color, to explore whether targeting dorsal or ventral stream processing influenced the strength of the left bias. It was expected that the left bias would be stronger on the motion task than on a task incorporating isoluminant color. In Study 1, similar left biases were observed during prolonged viewing for luminance, motion and red, but not green color. The unexpected finding of a leftward bias for red under prolonged viewing was replicated in Study 2. A leftward bias for motion was also evident during 150 ms viewing in Study 2. In Study 3, the left bias was not apparent when using a blue/yellow condition, suggesting the left bias for red under prolonged viewing was likely unique to red. Furthermore, the leftward bias for red disappeared under brief viewing conditions. It is suggested that dorsal stream processing likely underlies visual field differences in pseudoneglect.