The data published in the journal PLOS ONE demonstrated that even a simple conversation can slow down important stages of eye movement necessary for adequate perception of the environment, especially while operating a vehicle.
In the experiment involving 30 healthy participants, researchers studied eye movements under three different conditions: during conversation, while listening to text, and at rest without additional stimuli. It was found that conversation specifically increased eye reaction time, slowed their movement towards targets, and worsened fixation on objects. These delays occurred at early stages of visual information processing.
The authors of the study noted that while each delay may seem insignificant, in real-world conditions, it can accumulate, leading to later detection of potential threats such as pedestrians, road obstacles, or signals. This is particularly important considering that about 90% of the information necessary for safe driving is obtained through vision.
The results of the study confirm that conversations, including hands-free calls, can subtly affect visually-motor functions that precede recognition and decision-making. Scientists emphasize that the cognitive load arising during conversation may be one of the factors increasing the likelihood of errors and traffic accidents in complex situations.
