摘要
目的研究双眼竞争的客观检测方法,并分析梭状回与视觉皮质的相关性。方法 6名受试者进行双眼竞争试验,受试者一只眼呈现8.57 Hz闪烁的平静表情面孔图片,另一只眼分别呈现12、15 Hz闪烁的恐惧表情面孔图片,并记录脑电图(electroencephalogram,EEG)信号。两个不同频率闪烁的刺激诱发稳态视觉诱发电位(steady state visual evoked potential,SSVEP),通过短时傅里叶变换(short time Fourier transformation,STFT)的时频分析方法,解析面孔刺激中双眼竞争的持续时间和交替频率,比较两侧梭状回面孔识别区(fusiform face area,FFA)与视觉皮质的相关系数。结果双眼竞争下左眼观看平静表情面孔的时长平均(411.6±73.8)ms,右眼观看恐惧表情面孔的时长平均(547.6±126.7)ms,不同组合下交替频率没有差异,左侧FFA与右侧相比,对恐惧表情面孔的加工更敏感,两侧FFA对恐惧表情面孔的加工没有频率差异。结论 SSVEP能作为双眼竞争中优势态感知的频率标记,成功对双眼竞争下视觉感知进行客观评价,双眼竞争和SSVEP结合的方法可用于视觉感知神经机制的研究。
Objective To study binocular rivalry （BR）objectively and the correlation between fusiform face area （FFA）and visual cortex.Methods Six subjects participated in this study,with one eye presented a normal face expres-sion picture flickered at 8.57 Hz,while the other presented a fearful face flickered at 12 Hz or 15 Hz,respectively.Electro-encephalogram（EEG）was recorded during this process.Steady state visual evoked potential（SSVEP）evoked by two flick-ering rates was analyzed by time-frequency analysis of short time fourier transformation（STFT）.The time index of BR was estimated and the correlation coefficient between FFA and visual cortex compared.Results The total average time was （411.6 ±73.8）ms for the left eye and （547.6 ±126.7）ms for the right eye.The switch rate of the two groups was not different,but the left FFA was more sensitive than the right FFA in process of the fearful face.Neither side of FFA had any frequency preference to the flickered fearful face.Conclusion SSVEP can be used as a frequency tag of BR or as a tool to evaluate visual sensation under BR objectively.SSVEP combined with BR can be used in research of neural mechanisms of visual awareness.
出处
《军事医学》
CAS
CSCD
北大核心
2015年第11期842-846,共5页
Military Medical Sciences
基金
国家杰出青年科学基金资助项目(31125013)
