Effects of Experience on Spatial Frequency Tuning in the Visual System: Behavioral, Visuocortical, and Alpha-band Responses
Effects of Experience on Spatial Frequency Tuning in the Visual System: Behavioral, Visuocortical, and Alpha-band Responses
复制标题
DOI：
10.1162/jocn_a_01524
复制
发表时间：
2020-06-01
影响因子：
3.2
通讯作者：
Keil, Andreas
中科院分区：
文献类型：
--
作者：
Friedl, Wendel M.;Keil, Andreas
使用电生理学和经典的恐惧条件反射范式，这项工作研究了自适应视觉皮层的变化，在50名本科生的样本空间频率调谐。高密度脑电图记录，而参与者观看400个单独提出的10个不同的空间频率的伽柏补丁的总试验。贴片闪烁产生扫描稳态视觉诱发电位（ssVEP）在13.33 Hz的时间频率，刺激对比度斜坡上升从0%到41%迈克尔逊在每个2800毫秒的试验过程中。在最后的200次试验中，选定范围的Gabor刺激（最低或最高空间频率，在参与者之间操纵）与厌恶的90 dB白色噪声听觉刺激配对。在行为和电生理水平上评估了配对和非配对光栅条件反射前后空间频率调谐的变化。具体而言，ssVEP振幅变化进行了评价的侧抑制和泛化趋势，而α带（8-12 Hz）活动的变化进行了测试，跨空间频率的泛化趋势，使用置换控制的F对比。扫描ssVEP振幅包络和α波段功率的总体时间过程是正交的，并且ssVEP被证明对空间频率调节不敏感。当观察恐惧条件空间频率时，α减少（阻塞）最为明显，阻塞沿着条件频率之前的空间频率梯度沿着减少，表明空间频率的泛化。结果表明，阿尔法功率降低概念上与参与的注意力和警觉性/唤醒机制恐惧条件刺激独立运作的低级别空间频率处理（索引ssVEPs）在初级视觉皮层。
Using electrophysiology and a classic fear conditioning paradigm, this work examined adaptive visuocortical changes in spatial frequency tuning in a sample of 50 undergraduate students. High-density EEG was recorded while participants viewed 400 total trials of individually presented Gabor patches of 10 different spatial frequencies. Patches were flickered to produce sweep steady-state visual evoked potentials (ssVEPs) at a temporal frequency of 13.33 Hz, with stimulus contrast ramping up from 0% to 41% Michelson over the course of each 2800-msec trial. During the final 200 trials, a selected range of Gabor stimuli (either the lowest or highest spatial frequencies, manipulated between participants) were paired with an aversive 90-dB white noise auditory stimulus. Changes in spatial frequency tuning from before to after conditioning for paired and unpaired gratings were evaluated at the behavioral and electrophysiological level. Specifically, ssVEP amplitude changes were evaluated for lateral inhibition and generalization trends, whereas change in alpha band (8-12 Hz) activity was tested for a generalization trend across spatial frequencies, using permutation-controlled F contrasts. Overall time courses of the sweep ssVEP amplitude envelope and alpha-band power were orthogonal, and ssVEPs proved insensitive to spatial frequency conditioning. Alpha reduction (blocking) was most pronounced when viewing fear-conditioned spatial frequencies, with blocking decreasing along the gradient of spatial frequencies preceding conditioned frequencies, indicating generalization across spatial frequencies. Results suggest that alpha power reduction-conceptually linked to engagement of attention and alertness/arousal mechanisms-to fear-conditioned stimuli operates independently of low-level spatial frequency processing (indexed by ssVEPs) in primary visual cortex.