Correlation between cortical inhibition and auditory stream segregation in a driving environment

Streams of information reach the brain in different modalities while driving (both from the vehicle user interface as well as the environment), each requiring a certain degree of attention from the driver. The driver should ideally be able to focus on the road ahead and not on secondary streams such as vehicle alerts, mobile phone, passengers or radio. However, the individual ability to selectively ignore distractions can have a direct influence on driving performance. Here, we use paired-chirp auditory late responses (ALRs) in order to assess long interval cortical inhibition (LICI) in healthy subjects, and compare it to the score in an auditory stream segregation task within a driving simulator. Results show significant correlation between LICI and task scores, suggesting that people with a higher/more effective cortical inhibition as measured by ALRs can ignore distracting streams easily, while people with less effective cortical inhibition find harder to concentrate on a single, more relevant stream. The fundamental results obtained suggest that cortical inhibition may be employed as a predictor of driving performance, useful for the design of auditory human-vehicle interfaces.