THE INFLUENCE OF SPATIAL LATERAL BIASES AND NATIVE READING DIRECTION ON DRIVING AND AESTHETIC PREFERENCES
The neglect of leftward space occurring after a right parietal lesion, known as hemispatial neglect, results in a rightward spatial bias. Neurotypical individuals display an opposite leftward spatial bias, known as pseudoneglect (Bowers & Heilman, 1980). The leftward lighting bias and the leftward aesthetic preference are hypothesized to be related to pseudoneglect (Smith & Elias, 2018). Leftward biases are attenuated, or even flipped to the right in certain circumstances, notably in participants whose native reading direction (NRD) moves from right-to-left (RTL) and when spatial tasks occur in extrapersonal space. Aesthetic preferences and spatial abilities were compared between RTL and left-to-right (LTR) groups in an image rating task using eye tracking (Chapter 2) and image lighting tasks of three-dimensional (3D) images of sculptures (Chapter 3) and two-dimensional (2D) images of abstract paintings (Chapter 4). Participants’ basic spatial ability was assessed using the greyscales task (Mattingley, Bradshaw, Nettleton, & Bradshaw, 1994), a measure of perceptual asymmetries. LTR and RTL participants show clearly diverging trends of behaviour when making aesthetic judgments. When examining 2D images in Chapter 2 and illuminating 2D images in Chapter 4, preferences were leftward among LTRs and rightward among RTLs, however, both groups demonstrated a consistent leftward bias on the greyscales task. In Chapter 3, similar group differences between professionals in LTR and RTL regions were found for sculpture lighting, but participants illuminating 3D sculpture images did not show any light placement biases. In Chapter 4, a rudimentary version of a virtual mapping technique known as Halos (Baudisch & Rosenholtz, 2003) was carried out in a procedurally similar way to the artwork lighting task of the same chapter but measured spatial abilities rather than aesthetic preferences. Contrary to predictions, smaller errors were made when estimating the size of halos on the right, and as circle size increased estimation accuracy decreased. Studies in Chapter 5 examined navigation spatial abilities when driving, experimentally using a driving simulation, and through the analysis of naturalistic data from the Strategic Highway Research Program Naturalistic Driving Study (SHRP 2 NDS). Lane deviations were rightward, and collisions were more frequent and severe on the right side in the simulation and naturalistic data analysis revealed greater likelihoods of collisions from crossing over the right line or edge of the road and when making a right turn. Overall, findings suggest that an RTL NRD and task complexity modulate pseudoneglect and that lateral spatial biases when driving are in line with previous lateral bumping when walking results. Across all studies, findings provide clarity about the occurrence leftward bias attenuation.
neglect, hemispatial neglect, pseudoneglect, leftward bias, spatial bias, lighting bias, aesthetics, aesthetic preference, driving, driving simulation, navigation, navigation spatial abilities, native reading direction, right to left reading direction
Doctor of Philosophy (Ph.D.)