Yurgil Kate A, Golob Edward J
VA Center of Excellence for Stress and Mental Health, San Diego, California, USA; VA San Diego Healthcare System, San Diego, California, USA; Department of Psychology, Tulane University, New Orleans, Louisiana, USA.
Psychophysiology. 2013 Dec;50(12):1263-74. doi: 10.1111/psyp.12140. Epub 2013 Sep 9.
This study determined whether auditory cortical responses associated with mechanisms of attention vary with individual differences in working memory capacity (WMC) and perceptual load. The operation span test defined subjects with low versus high WMC, who then discriminated target/nontarget tones while EEG was recorded. Infrequent white noise distracters were presented at midline or ±90° locations, and perceptual load was manipulated by varying nontarget frequency. Amplitude of the N100 to distracters was negatively correlated with WMC. Relative to targets, only high WMC subjects showed attenuated N100 amplitudes to nontargets. In the higher WMC group, increased perceptual load was associated with decreased P3a amplitudes to distracters and longer-lasting negative slow wave to nontargets. Results show that auditory cortical processing is associated with multiple facets of attention related to WMC and possibly higher-level cognition.
本研究确定了与注意力机制相关的听觉皮层反应是否会因工作记忆容量（WMC）和知觉负载的个体差异而有所不同。运算广度测试界定了低WMC和高WMC的受试者，然后在记录脑电图的同时让他们辨别目标/非目标音调。不频繁出现的白噪声干扰刺激呈现在中线或±90°位置，通过改变非目标频率来操纵知觉负载。干扰刺激的N100波幅与WMC呈负相关。相对于目标而言，只有高WMC受试者对非目标的N100波幅有所衰减。在高WMC组中，知觉负载增加与干扰刺激的P3a波幅降低以及非目标的负向慢波持续时间延长有关。结果表明，听觉皮层处理与注意力的多个方面相关，这些方面与WMC以及可能的高级认知有关。
