Knowledge Media Research Center, Tuebingen, Germany Department of Psychology, Eberhard Karls University, Tuebingen, Germany.
Br J Psychol. 2011 Aug;102(3):623-45. doi: 10.1111/j.2044-8295.2011.02034.x. Epub 2011 Apr 27.
Recent research indicated that processes of unit-decade integration pose particular difficulty on multi-digit addition. In fact, longer response latencies as well as higher error rates have been observed for addition problems involving a carry operation (e.g., 18 +27) compared to problems not requiring a carry (e.g., 13 +32). However, the cognitive instantiation of this carry effect remained unknown. In the current study, this question was pursued by recording participants' eye fixation behaviour during addition problem verification. Analyses of the eye fixation data suggested a prominent role of the unit digits of the summands. The need for a carry seems to be recognized very early during the encoding of the problem after initial unit sum calculation has established the basis for the no carry/carry detection. Additionally, processes related to the actual carry execution seemed to be associated with the processing of the decade digit of the solution probe but were less unambiguous. Taken together, our findings indicate that unit-based calculations and the associated recognition that a carry is needed as well as its completion determine the difficulty of carry addition problems. On a more general level, this study shows how the nature of numerical-cognitive processes can be further differentiated by the evaluation of eye movement measures.
最近的研究表明，在多位数字加法中，单位十进制整合过程特别困难。事实上，与不需要进位的问题（例如 13 + 32）相比，涉及进位操作的加法问题（例如 18 + 27）会观察到更长的反应时和更高的错误率。然而，进位效应的认知体现仍然未知。在本研究中，通过记录参与者在加法问题验证过程中的眼动行为来探讨这个问题。对眼动数据的分析表明，加数的单位数字起着重要作用。在初始单位和计算为无进位/进位检测奠定基础后，对问题进行编码时似乎很早就需要进位。此外，与实际进位执行相关的过程似乎与解探针的十年数字的处理有关，但不太明确。总的来说，我们的发现表明，基于单位的计算以及对进位的需求和进位的完成决定了进位加法问题的难度。在更广泛的层面上，这项研究表明，通过评估眼动测量，如何进一步区分数值认知过程的性质。
