title: Perceptual load in different regions of the visual scene and its relevance for driving.
abstract: OBJECTIVE
  The aim of this study was to better understand the role played by perceptual load, at both central and peripheral regions of the visual scene, in driving safety.
  
  
  BACKGROUND
  Attention is a crucial factor in driving safety, and previous laboratory studies suggest that perceptual load is an important factor determining the efficiency of attentional selectivity. Yet, the effects of perceptual load on driving were never studied systematically.
  
  
  METHODS
  Using a driving simulator, we orthogonally manipulated the load levels at the road (central load) and its sides (peripheral load), while occasionally introducing critical events at one of these regions.
  
  
  RESULTS
  Perceptual load affected driving performance at both regions of the visual scene. Critically, the effect was different for central versus peripheral load: Whereas load levels on the road mainly affected driving speed, load levels on its sides mainly affected the ability to detect critical events initiating from the roadsides. Moreover, higher levels of peripheral load impaired performance but mainly with low levels of central load, replicating findings with simple letter stimuli.
  
  
  CONCLUSIONS
  Perceptual load has a considerable effect on driving, but the nature of this effect depends on the region of the visual scene at which the load is introduced.
  
  
  CONCLUSIONS
  Given the observed importance of perceptual load, authors of future studies of driving safety should take it into account. Specifically, these findings suggest that our understanding of factors that may be relevant for driving safety would benefit from studying these factors under different levels of load at different regions of the visual scene.
authors.affiliation: University of Haifa, Haifa, Israel hmarcia1@univ.haifa.ac.il.
authors.forename: Hadas
authors.initials: H
authors.lastname: Marciano
authors.affiliation: University of Haifa, Haifa, Israel.
authors.forename: Yaffa
authors.initials: Y
authors.lastname: Yeshurun
mesh_terms: D000063:Accidents, Traffic / Q000706:statistics & numerical data*; D000328:Adult; D001288:Attention / Q000502:physiology*; D001334:Automobile Driving / Q000592:standards / Q000706:statistics & numerical data; D003198:Computer Simulation; D005260:Female; D006801:Humans; D008297:Male; D011930:Reaction Time / Q000502:physiology*; D012449:Safety; D014796:Visual Perception; D055815:Young Adult
keywords: driving distraction; driving simulator; perceptual load; selective attention