Abstract:

 Objective  To explore the visual health and fatigue induced by watching three dimensional (3D) video using electroencephalogram (EEG). Design Experimental study. Participants Forty healthy subjects, aged 20 to 30 years old, with refractive status being emmetropia, or mild myopia (sphere power >-3.0 D, cylinder power changed between -1.0D~+1.0D). Methods Every subject watched 40 minutes video showed in two kinds of pattern, two dimension (2D) and tree dimension (3D) video with the same content in different two days.  Electroencephalogram (EEG) analyzer was used to record EEG signal changing when subjects watching 2D or 3D video with real time.  EEG signals of relative energy in α, β, θ and δ rhythms, R value, AB value and gravity frequency in 2D video pattern and 3D video pattern were compared, using software of EEG analyzer and statistics methods. Main Outcome Measures    EEG parameters include relative energy of α, β, θ, δ rhythms, and R value, AB value and gravity frequency. Results   EEG signals of 22 subjects watching 2D pattern video and 35 subjects watching the same film in 3D pattern were evaluated.  Relative energy of α rhythm was larger in watching 2D video pattern than that in watching 3D video pattern. Relative energy of β rhythm was lower in watching 2D video pattern than that in watching 3D video pattern. Relative energy of θ rhythm in watching 2D pattern video was close to watching 3D pattern video. Relative energy of δ rhythm was higher in watching 3D pattern. R value and AB value were larger in watching 2D pattern video than those in watching 3D pattern video, and this difference was lessened with time. Gravity frequency was higher in watching 3D pattern video. The relative energy of α, β, θ and δ rhythms in different brain areas behaved differently in watching 2D and 3D patterns video. O1, O2, Oz, TP8 and T5 channels of  relative energy ofαrhythm, the difference was significant, compared among 4 time periods (watching video for 10 min, 20min, 30 min, 40min), Pvalues were 0.03， 0.03， 0.02， 0.05， 0.04, respectively. The relative energy of α rhythm decreased with viewing time extension. The differences of relative energy of β rhythm in T3 channel was significant among 4 time periods, P value was 0.03. The relative energy of β rhythm increased with viewing time extension. T5 and T8 channels of relative energy of α rhythm was significantly higher in 2D than in 3D pattern video(P=0.02, 0.01 respectively). T3 channel of relative energy of β rhythm was significantly lower in 2D than in 3D pattern video(P=0.001). The R value in watching 3D pattern video was always higher than the ones in watching 2D pattern video, and the AB values were consistent with the change of R values. Conclusion EEG was used to evaluate the effect to health and fatigue in viewing 3D pattern video, the relative energy of α and β rhythm, and fatigue factor R value are consistent with the state of alert and nervous in the brain during 40 min for viewing 3D pattern video. Because 3D video information the brain processing is so rich, the brain may gradually produce fatigue with the viewing time extension. (Ophthalmol CHN, 2015, 24: 324-331)

Key words: three dimension video, electroencephalogram, stereo vision; , fatigue