Comparison of manual vs. speech-based interaction with in-vehicle information systems

  • Published: Accident Analysis & Prevention, 41(5), 2009
  • Authors: Maciej, J., & Vollrath, M.
  • Date Added: 28 Mar 2015
  • Last Update: 28 Mar 2015
  • Format: html


This study examined whether speech-based interfaces for different in-vehicle-information-systems (IVIS) reduce the distraction caused by these systems.


For three frequently used systems (audio, telephone with name selection, navigation system with address entry and point of interest selection) speech, manual control and driving without IVIS (baseline) were compared. The Lane Change Task was used to assess driving performance. Additionally, gaze behavior and a subjective measure of distraction were analyzed.

The subjects were 30 drivers (16 male, 14 female) who had normal or corrected to normal vision. All had a valid driver's license. The age ranged from 19 to 59 with a mean age of 33.2 (SD = 11.9). They were paid 10€ an hour for the two to three hours they took to complete the experiment.

Key Findings:

  • Speech interfaces improved driving performance, gaze behavior and subjective distraction for all systems with the exception of point-of-interest entry.

  • However, these improvements were overall not strong enough to reach the baseline performance level.

  • Only in easy segments of the driving task the performance level was comparable to baseline.

  • Thus, speech-based IVIS have to be further developed to keep the cognitive complexity at an adequate level which does not disturb driving. However, looking at the benefits, speech control is a must for the car of the future.