ABSTRACT
Objective T o study the effect of different attentional conditions on the event-related potential (E R P ) com ponents generated by the visual inform ation stim uli related to visual acuity, and provide a theoretical reference for clinical forensic visual objective evaluation. Methods W ith visual acuity opto-types as norm al form of visual inform ation stim uli, 15 volunteers as study subjects w ere supposed to ac-count the visual acuity optotypes under the attentional condition of visual stim uli. Furtherm ore, the sub-jects w ere required to listen to the storytelling carefully under the non-attentional condition of visual stim uli, and after the exam ination, they needed to answ er the story-related questions. A ll the E E G re-sults of tw o different attentional conditions from the subjects w ere recorded by 32 channel E R P system . Results U nder tw o attentional conditions, P 1 and P 300 com ponents w ere evoked by the visual acuity opto-types on supra-threshold and threshold visual acuity levels, w hile only P 1 com ponent w ere evoked by the visual acuity optotypes on sub-threshold levels. In the E R P w aveform s evoked by the visual acuity optotypes on supra-threshold, P 1 and P 300 am plitudes under attentional condition w ere larger than that un-der non-attentional condition. Conclusion A ttentional conditions can influence the detection of visual acuity. P 300 com ponent can be used to distinguish the visual acuity levels w ith supra-threshold and sub-threshold under non-attentional condition.