Comparing eye movements recorded by search coil and infrared eye tracking

OBJECTIVE: The performance of a new video-based infrared eye tracker (IR) was compared to the magnetic search coil technique (SC). Since the IR offers interesting possibilities as a diagnostic tool in neuro-ophthalmology, it was investigated whether the new device has overcome shortcomings that were reported from former IR systems. METHODS: Horizontal saccades were recorded using the IR and the SC. The IR allowed eye movement recordings at different sampling rates ranging from 250 Hz to 1000 Hz while the SC recorded at 1000 Hz. RESULTS/CONCLUSIONS: The results show that the IR and the SC were in good agreement and produced similar results. In contrast to other studies, the influence of the sampling rate of the IR was small. The saccade main-sequences did not show significant differences. The latency times observed for both systems were mainly in the short-latency range

Trauma BiomechanicsAn Introduction to Injury Biomechanics /

XVI, 243 p. 111 illus.online resource

Saccadic eye movements after low-dose oral alcohol exposure

OBJECTIVES: The influence of low-dose alcohol intake on reflexive visually guided saccades was investigated. METHODS: 40 healthy human subjects were orally given alcohol resulting in low-dose alcohol concentration (less than 0.8‰) blood alcohol concentration. Before and after exposure, horizontal saccadic eye movements were recorded at several points in time. The recordings were evaluated with regard to accuracy of the eye movements, latency, the peak eye velocity and the time constant that characterizes the main sequence. The results were compared to recordings from a reference group. RESULTS: It was found that the saccadic eye movement was clearly altered by low-dose alcohol intake. However, its characteristics were not unambiguously pathological when compared to the reference group, even though the subjects reported a moderate to strong effect of alcohol and there were clear signs of inebriation. CONCLUSIONS: The findings render the evaluation of saccades unsuitable as a simple test for the detection of low-dose alcohol intake