Temporal Tuning of Word- and Face-selective Cortex.
Temporal Tuning of Word- and Face-selective Cortex.
复制标题
单词和面部选择性皮层的时间调整。
DOI：
10.1162/jocn_a_01002
复制
发表时间：
2016
影响因子：
3.2
通讯作者：
Norcia,AnthonyM
中科院分区：
文献类型：
--
作者：
Yeatman,JasonD;Norcia,AnthonyM
对时间变化的敏感性对视觉系统中的对象处理产生了根本性的限制。一个新兴的共识，从行为和神经影像学文献表明，时间分辨率有很大的不同，为刺激的不同复杂性和大脑区域在不同层次的皮层层次。在这里，我们使用稳态视觉诱发电位直接测量三个基本参数，这些参数表征了对文本和人脸图像的潜在神经反应：时间分辨率，峰值时间频率和反应延迟。我们呈现了文本或人脸的全屏图像，与乱序图像交替，时间频率在1到12 Hz之间。这些图像在第一谐波处引起了稳健的响应，其显示了文本和面部图像的差分调谐、头皮形貌和延迟。面部选择性反应在4 Hz时最大，而文本选择性反应在1 Hz时最大。地形的文字图像的反应是强烈的左侧在较高的刺激率，而面部图像的反应是轻微的右侧，但几乎双边在所有频率。文本和面部图像都在一个以上的明显潜伏期引起稳态活动;我们观察到早期（141-160毫秒）和晚期（>250毫秒）的文本和面部选择性反应。这些差异的时间调谐配置文件很可能反映了不同的性质的计算执行的字和脸的选择性皮层。尽管文字和面孔选择性区域的皮质表面上的紧密接近，我们的测量表明，在时间动态的文字与面孔选择性反应的实质性差异。
Sensitivity to temporal change places fundamental limits on object processing in the visual system. An emerging consensus from the behavioral and neuroimaging literature suggests that temporal resolution differs substantially for stimuli of different complexity and for brain areas at different levels of the cortical hierarchy. Here, we used steady-state visually evoked potentials to directly measure three fundamental parameters that characterize the underlying neural response to text and face images: temporal resolution, peak temporal frequency, and response latency. We presented full-screen images of text or a human face, alternated with a scrambled image, at temporal frequencies between 1 and 12 Hz. These images elicited a robust response at the first harmonic that showed differential tuning, scalp topography, and delay for the text and face images. Face-selective responses were maximal at 4 Hz, but text-selective responses, by contrast, were maximal at 1 Hz. The topography of the text image response was strongly left-lateralized at higher stimulation rates, whereas the response to the face image was slightly right-lateralized but nearly bilateral at all frequencies. Both text and face images elicited steady-state activity at more than one apparent latency; we observed early (141–160 msec) and late (>250 msec) text- and face-selective responses. These differences in temporal tuning profiles are likely to reflect differences in the nature of the computations performed by word- and face-selective cortex. Despite the close proximity of word- and face-selective regions on the cortical surface, our measurements demonstrate substantial differences in the temporal dynamics of word- versus face-selective responses.