情境对分数和小数影响的ERP研究

An ERP Study on the Processing of Common and Decimal Fractions Affected by Contexts

本研究采用数量比较的分类范式测定了14名大学生完成任务时的事件相关电位(ERPs)。实验设置了单纯和混合两种情境以考察情境是否对分数和小数有不同的影响,探讨两种符号数字是否表现出特异性的加工。行为数据显示:分数受情境影响显著,而小数不受情境影响。电生理结果显示:在分数条件中,N1、P2和P2p的波幅及N2的潜伏期都受情境影响,而在小数条件中,只有N2的波幅和潜伏期受情境影响。这些结果表明分数和小数的特异性加工主要源于知觉辨别,符号意义的提取,数量大小表征和分类反应关联阶段的差异。

Event-related potentials （ERPs） were measured in the brains of 14 normal young adults carrying out a magnitude comparison task. Our experiment included a simple context consisting exclusively of common fractions or decimal fractions, and a mixed context with both symbols interspersed. The aim of the present study was to examine the critical distinction between the processing of common fractions versus that of decimal fractions by comparing the context effect of the two symbols. The results showed that： Context had an effect on error rate for common fractions but not for decimal fractions. Our electrophysiological data reflected symbol-specific processing in N1, P2p, P2 and N2. Context did affect N1, P2p and P2 amplitude, and N2 latency for common fractions. Only N2 amplitude and latency were affected by context for decimal fractions. Our results indicated that differences in perceptual identification, extraction of numeral symbolic meaning, numerical magnitude representation and category-response associations may be the main source of the specific processing differences between common and decimal fraction symbols.