Behavioral Ecology Meets Motor Behavior: Choosing Between Walking and Reaching Paths

ABSTRACT

Behavioral ecology is a field in which scientists try to predict behavioral choices, typically by estimating costs of behavioral alternatives even though those costs may involve different currencies. Researchers interested in motor behavior often have similar concerns, though the connections between these two fields have been largely unnoticed. The authors pursued a study of motor behaviors involving different currencies: walking over different distances and reaching over different distances. They found that the cost of reaching was much greater than the cost of walking. They also found that walking paths took into account hand preferences. The present study extends previous research on the neglected topic of the coordination of reaching and walking and provides a simple method that can be applied in other contexts.

Keywords:

• ecology
• locomotion
• planning
• reaching
• walking

ACKNOWLEDGMENTS

The authors are indebted to Carrie Gager and Casey Kennedy for help with data collection and to Chase Coelho, Rajal Cohen, Lanyun Gong, Steven Jax, Joe Santamaria, and Jonathan Vaughan for helpful comments during the conduct of this research. They also thank Richard Carson and two anonymous reviewers for helpful feedback on a first submission of this work. Finally, the authors thank Dennis Proffitt for pointing out the links between this study and the field of behavioral ecology.

The research was aided by grants from the National Science Foundation and the National Institutes of Health.

Notes

As far as we know, there has been little or no work on the evolving transition from one phase relation to the other during shifts from ordinary gait to walking with lifting or vice versa, from walking while holding a lifted object back to ordinary walking after setting down the grasped object or otherwise releasing it. Ongoing research in our lab is concerned with this topic.

Jonathan Zadra (personal communication, September 16, 2010) of the University of Virginia conducted an experiment modeled after the experiment reported in the present article. According to him, the data from his experiment were very similar to the data reported for the experiment reported here.