title: Greater Activity in the Frontal Cortex on Left Curves: A Vector-Based fNIRS Study of Left and Right Curve Driving.
abstract: OBJECTIVE
  In the brain, the mechanisms of attention to the left and the right are known to be different. It is possible that brain activity when driving also differs with different horizontal road alignments (left or right curves), but little is known about this. We found driver brain activity to be different when driving on left and right curves, in an experiment using a large-scale driving simulator and functional near-infrared spectroscopy (fNIRS).
  
  
  METHODS
  The participants were fifteen healthy adults. We created a course simulating an expressway, comprising straight line driving and gentle left and right curves, and monitored the participants under driving conditions, in which they drove at a constant speed of 100 km/h, and under non-driving conditions, in which they simply watched the screen (visual task). Changes in hemoglobin concentrations were monitored at 48 channels including the prefrontal cortex, the premotor cortex, the primary motor cortex and the parietal cortex. From orthogonal vectors of changes in deoxyhemoglobin and changes in oxyhemoglobin, we calculated changes in cerebral oxygen exchange, reflecting neural activity, and statistically compared the resulting values from the right and left curve sections.
  
  
  RESULTS
  Under driving conditions, there were no sites where cerebral oxygen exchange increased significantly more during right curves than during left curves (p > 0.05), but cerebral oxygen exchange increased significantly more during left curves (p < 0.05) in the right premotor cortex, the right frontal eye field and the bilateral prefrontal cortex. Under non-driving conditions, increases were significantly greater during left curves (p < 0.05) only in the right frontal eye field.
  
  
  CONCLUSIONS
  Left curve driving was thus found to require more brain activity at multiple sites, suggesting that left curve driving may require more visual attention than right curve driving. The right frontal eye field was activated under both driving and non-driving conditions.
authors.affiliation: Department of Brain Environmental Research, KatoBrain Co., Ltd., Tokyo, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Oka
authors.affiliation: Department of Brain Environmental Research, KatoBrain Co., Ltd., Tokyo, Japan.
authors.forename: Kayoko
authors.initials: K
authors.lastname: Yoshino
authors.affiliation: Department of Environment/Engineering, Tokyo Branch, Central Nippon Expressway Co., Ltd, Tokyo, Japan.
authors.forename: Kouji
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: Department of Environment/Engineering, Central Nippon Expressway Co., Ltd., Nagoya, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Takahashi
authors.affiliation: Institute of Industrial Science, the University of Tokyo, Tokyo, Japan.
authors.forename: Shuguang
authors.initials: S
authors.lastname: Li
authors.affiliation: Institute of Industrial Science, the University of Tokyo, Tokyo, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Sugimachi
authors.affiliation: Institute of Industrial Science, the University of Tokyo, Tokyo, Japan.
authors.forename: Kimihiko
authors.initials: K
authors.lastname: Nakano
authors.affiliation: Institute of Industrial Science, the University of Tokyo, Tokyo, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Suda
authors.affiliation: Department of Brain Environmental Research, KatoBrain Co., Ltd., Tokyo, Japan.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Kato
mesh_terms: D000328:Adult; D001334:Automobile Driving; D005260:Female; D005625:Frontal Lobe / Q000502:physiology*; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D019265:Spectroscopy, Near-Infrared / Q000379:methods*