Spatial attention: differential shifts in pseudoneglect direction with time-on-task and initial bias support the idea of observer subtypes.
Asymmetry in human spatial attention has long been documented. In the general population the majority of individuals tend to misbisect horizontal lines to the left of veridical centre. Nonetheless in virtually all previously reported studies on healthy participants, there have been subsets of people displaying rightward biases. In this study, we report differential time-on task effects depending on participants' initial pseudoneglect bias: participants with an initial left bias in a landmark task (in which they had to judge whether a transection mark appeared closer to the right or left end of a line) showed a significant rightward shift over the course of the experimental session, whereas participants with an initial right bias shifted leftwards. We argue that these differences in initial biases as well as the differential shifts with time-on task reflect genuine observer subtypes displaying diverging behavioural patterns. These observer subtypes could be driven by differences in brain organisation and/or lateralisation such as varying anatomical pathway asymmetries (Thiebaut de Schotten et al., 2011).
Centre for Cognitive Neuroimaging, Institute of Neuroscience and Psychology, University of Glasgow, Glasgow 58 Hillhead Street, G12 8QB, United Kingdom; School of Psychology, University of Glasgow, Glasgow G12 8QB, United Kingdom.
Christopher S Y
CS
Benwell
Gregor
G
Thut
Gemma
G
Learmonth
Monika
M
Harvey
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology*; D015982:Bias; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D010775:Photic Stimulation; D011594:Psychometrics; D012890:Sleep / Q000502:physiology; D013028:Space Perception / Q000502:physiology*; D013997:Time Factors; D055815:Young Adult
Attentional biases; Hemispatial neglect; Landmark; Lateralisation; Line bisection