Experimental Brain Research

, Volume 184, Issue 1, pp 115–120 | Cite as

Effects of a secondary task on obstacle avoidance in healthy young adults

  • Ka-Chun Siu
  • Robert D. Catena
  • Li-Shan Chou
  • Paul van Donkelaar
  • Marjorie H. Woollacott
Research Article


Research on attention and gait stability has suggested that the process of recovering gait stability requires attentional resources, but the effect of performing a secondary task on stability during obstacle avoidance is poorly understood. Using a dual-task paradigm, the present experiment investigated the extent to which young adults are able to respond to a secondary auditory Stroop task (requiring executive attentional network resources) concurrently with obstacle crossing during gait when compared with performing unobstructed walking or sitting (control task). Our results demonstrated that as the level of difficulty in the postural task increased, there was a significant reduction in verbal response time from congruent to incongruent conditions in the auditory Stroop task, but no differences in gait parameters, indicating that these postural tasks require attention, and that young adults use a strategy of modulating the auditory Stroop task performance while keeping stable gait performance under the dual-task situations. Our findings suggest the existence of a hierarchy of control within both postural task (obstacle avoidance requires the most information processing resources) and dual-task (with gait stability being a priority) conditions.


Attention Obstacle avoidance Dual-task paradigm Gait 



This study was support by the National Institute of Health, Aging Grant # AG-021598 (M. Woollacott, PI).


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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Ka-Chun Siu
    • 1
    • 3
  • Robert D. Catena
    • 2
  • Li-Shan Chou
    • 2
  • Paul van Donkelaar
    • 3
  • Marjorie H. Woollacott
    • 3
  1. 1.HPER Biomechanics LaboratoryUniversity of Nebraska at OmahaOmahaUSA
  2. 2.Motion Analysis Laboratory, Department of Human PhysiologyUniversity of OregonEugeneUSA
  3. 3.Motor Control Laboratory, Department of Human PhysiologyUniversity of OregonEugeneUSA

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