A prospective study of loss of consciousness in epilepsy using virtual reality driving simulation and other video games

Abstract

Patients with epilepsy are at risk of traffic accidents when they have seizures while driving. However, driving is an essential part of normal daily life in many communities, and depriving patients of driving privileges can have profound consequences for their economic and social well-being. In the current study, we collected ictal performance data from a driving simulator and two other video games in patients undergoing continuous video/EEG monitoring. We captured 22 seizures in 13 patients and found that driving impairment during seizures differed in terms of both magnitude and character, depending on the seizure type. Our study documents the feasibility of a prospective study of driving and other behaviors during seizures through the use of computer-based tasks. This methodology may be applied to further describe differential driving impairment in specific types of seizures and to gain data on anatomical networks disrupted in seizures that impair consciousness and driving safety.

Fig. 1. Performance on rFactor driving simulator during different seizure types

Change in driving performance over time is shown for representative examples of different types of seizures. All of the variable units are arbitrary game units. (A) Partial seizure (Patient 5). (B) Partial seizure (Patient 6). Note that after the second collision the throttle remained depressed for a while but the car did not move since it had collided with a wall. (C) Absence seizure (Patient 13). Note that the first two collisions occurred very close together and appear merged at this time resolution. (D) Secondarily generalized seizure (Patient 10). Driving performance variables shown include the following: Steering wheel velocity (top row) is the absolute value of the derivative of the steering wheel position vs. time. This value represents the quantity of steering wheel position changes at each time point and was used as a measure of patients’ engagement in avoiding collisions. Throttle (second row) shows engagement of the throttle, where 1.0 means the gas pedal is fully depressed and 0 means the patient’s foot is off the pedal. Car position (third row) displays the location of the vehicle in terms of the game world grid, according to two dimensions x and y vs. time as the car travels around the track in the x-y plane. If the car is moving, then one or both of these values should change over time. Car velocity (fourth row) shows vehicle’s total speed as it moves along the track vs. time. In all plots, time is relative to seizure onset, which is set to time 0 s. The red line indicates seizure onset. The green line indicates seizures offset. Black lines represent collisions.