数字-空间联结SNARC效应的编码：视觉空间和言语空间

采用Gevers等的实验范式,以判断数字大小并选择不同言语符号方向信息左右为任务。材料为阿拉伯数字（1、2、8、9）和汉字、英文单词符号（“左”、“右”、“left”、“m#t”）。考察在不同语言符号方向信息下数字-空间联结SANBC效应的编码方式,结果发现：（1）在汉字和英文符号信息下,被试在数字大小比较任务中都表现出SNARC效应;（2）在汉字符号方向信息下。SNARC效应的编码方式主要存在视觉空间和言语空间编码,且以言语空间编码为主;（3）在英文符号方向信息下。SNARC效应的鳊码方式主要是视觉空间编码。     

视觉和言语空间信息共同作用下SNARC效应的空间参照特点

已有研究显示,SNARC效应存在多个灵活的空间参照系统,可在不同的实验条件下激活。心理数字线理论对于SNARC效应空间编码的理解仅局限于物理空间层面,并不能很好地甄别SNARC效应空间参照系统的激活条件。研究以视觉空间和言语空间双编码理论为基础,考查在视觉空间信息与言语空间信息共同作用下,单手（左手或右手）与双手反应下SNARC效应的空间参照特点。结果显示,在视觉空间信息与言语空间信息共同作用下,左手、右手和双手反应下均出现了典型SNARC效应,且左手、右手和双手反应下的数字空间映射模式相似。研究结果证实,在视觉-空间与言语空间信息共同作用下仅激活SNARC效应多个灵活的空间参照系统中的身体中心为基础的参照系统,说明言语空间信息的参与有助于激活该效应中身体中心为基础的空间参照系统。     

符号数量和非符号数量的空间表征:5岁儿童的SNARC效应和距离效应

对物理刺激的数量信息表征是符号数字表征的前提和基础,据此假设在儿童的SNARC效应发生的时序问题上,非符号数量(如面积)的空间表征早于符号数量(如阿拉伯数字)的空间表征。本研究邀请5岁幼儿完成数字比较和面积比较两类任务,结果发现在数字比较任务中没有出现SNARC效应,但却存在距离效应;在面积比较任务中出现了SNARC效应和距离效应。可以推断,在阿拉伯数字的空间表征出现之前,儿童已经能够对非符号数量信息进行空间表征。     

Task instructions determine the visuospatial and verbal–spatial nature of number–space associations

Evidence for number–space associations comes from the spatial–numerical association of response codes (SNARC) effect, consisting in faster reaction times to small/large digits with the left/right hand, respectively. Two different proposals are commonly discussed concerning the cognitive origin of the SNARC effect: the visuospatial account and the verbal–spatial account. Recent studies have provided evidence for the relative dominance of verbal–spatial over visuospatial coding mechanisms, when both mechanisms were directly contrasted in a magnitude comparison task. However, in these studies, participants were potentially biased towards verbal–spatial number processing by task instructions based on verbal–spatial labels. To overcome this confound and to investigate whether verbal–spatial coding mechanisms are predominantly activated irrespective of task instructions, we completed the previously used paradigm by adding a spatial instruction condition. In line with earlier findings, we could confirm the predominance of verbal–spatial number coding under verbal task instructions. However, in the spatial instruction condition, both verbal–spatial and visuospatial mechanisms were activated to an equal extent. Hence, these findings clearly indicate that the cognitive origin of number–space associations does not always predominantly rely on verbal–spatial processing mechanisms, but that the spatial code associated with numbers is context dependent.     

The effect of working memory load on the SNARC effect: Maybe tasks have a word to say

We investigated the effect of working memory load on the SNARC (spatial–numerical association of response codes) effect under different number judgment tasks (parity judgment and magnitude comparison), using a novel dual task. Instead of exerting load over the whole block of number judgment trials, in this dual task, number judgment trials were inserted into each interstimulus interval of an n-back task, which served as the working memory load. We varied both load type (verbal and spatial) and amount (1-load, 2-load, and 3-load). The results indicated that the SNARC effect disappeared even under the 1-load condition for a parity judgment, regardless of the type of load. However, during the magnitude comparison task, the SNARC effect increased with increasing load amounts under spatial load conditions; under verbal load conditions, the SNARC effect decreased with increasing amounts of load, and disappeared during the 3-load task. The difference between the parity and magnitude tasks was not attributable to the interval stimuli or task switching. These findings confirm that different spatial–numerical associations for comparing numerical magnitudes and judgments of parity have different needs with respect to working memory resources.     

视觉空间指令条件下SOAs变化对数字-空间联结编码的影响:来自ERP的证据

采用数字奇偶判断任务,以数字1-9(5除外)及汉字标签(左、右)作为实验材料,在视觉空间任务指令下探讨系统改变SOAs对数字-空间联结编码方式的影响。行为结果发现,SNARC效应以视觉空间编码方式为主,SOA为0ms并未出现SNARC效应; ERP结果发现,物理一致性在早期成分N1上的主效应显著。表明任务指导语影响SNARC效应的编码方式,其本质受词语信息标签加工程度的影响,且对SNARC效应的编码出现早期感觉阶段,SOAs与目标数字的特性影响SNARC效应的产生。     

刺激模拟量的空间表征:面积和亮度的类SNARC效应

在数字比较任务中的SNARC效应表明心理数字线具有空间上从左到右的方向性。本研究在两个实验中分别用面积和亮度作为比较刺激来探讨SNARC效应是否存在于面积比较任务和亮度比较任务中。实验结果显示,面积比较和亮度比较任务中存在类SNARC效应。     

物理大小和面积的无意识空间表征

意识水平的研究发现,数字量的比较机制与物理刺激比较的机制是一样的;在无意识水平上的研究发现,数字加工存在无意识语义启动现象。我们假设,在数字的物理特性的比较任务中可能存在无意识启动效应和类SNARC效应。实验一的数字比较任务和数字的物理大小比较任务发现,在33毫秒的无意识启动条件下,数字语义比较任务和数字物理大小比较任务中都发现了类SNARC效应、启动效应以及Stroop效应。实验二的数字覆盖面积比较任务中发现,在33毫秒的启动水平,数字比较与数字覆盖面积的比较任务中均存在SNARC效应、Stroop效应和启动效应。     

不同加工深度非符号数量信息的SNARC效应：眼动证据

通过两项眼动实验考察了个体在水平和垂直方向上对点阵数量进行较浅(浏览)和较深(数字比较)程度加工时的数量空间表征联系。结果显示：点阵在水平方向上出现了SNARC效应, 且SNARC效应的大小不受加工深浅的影响, 而在垂直方向上没有出现SNARC效应。表明(1)点阵数量SNARC效应的稳定性不如阿拉伯数字; (2)方向对点阵SNARC效应的影响更大, 加工程度的影响则不明显。结合加工程度、空间方向和点阵数量的自身特征等对研究发现进行了讨论, 认为数字的空间表征在多个因素的共同影响下可能呈现出多样性。     

Cognitive control acts locally

Cognitive control adjusts information processing to momentary needs and task requirements. We investigated conflict adaptation when participants are performing two tasks, a Simon task and a SNARC task. The results indicated that one congruency effect (e.g., Simon) was reduced after conflict in the other task (e.g., SNARC), but only when both tasks used identical relevant information. On the other hand, when both tasks used different relevant information, a larger congruency effect was observed after conflict in the other task. The results are explained in terms of a local control mechanism.     

数字空间联结的灵活性及其内在机制

数字空间联结一直是认知心理学领域研究的热点之一。探索数字空间联结的一个重要指标为空间-数字反应联合编码(spatial-numerical association of response codes, SNARC)效应(左/右手对小/大数反应更快更准确)。以往研究已验证SNARC效应的普遍性及其在方向上的灵活性, 并提出多种理论解释。此外, SNARC效应在加工阶段上也具有灵活性, 其原因可能有：(1)加因素法则的理解偏差; (2)观察的角度单一; (3)观察效标的差异; (4)使用任务的差异。结合以上因素, 提出双阶段(数量信息的空间表征、空间表征到反应选择)加工模型, 不同的操控因素分别作用于两个阶段可能是引起SNARC效应灵活变化的核心原因。未来研究可从对比任务差异、引入不同干扰因素等方面进一步验证双阶段加工模型, 并结合认知神经科学技术揭示数字空间联结灵活性的内在神经机制。     

身体形式和社会环境对SNARC效应的影响:基于具身认知观的理解

目前SNARC效应在认知心理学领域得到了广泛研究,然而较少有研究考察身体形式和社会环境对SNARC效应的影响.研究以127名在校大学生为被试,使用奇偶判断任务、Go/No-go任务以及合作情境下的Go/No-go任务依次展开了三个研究,拟揭示身体形式和社会环境对SNARC效应的影响.实验一要求被试双手完成奇偶判断任务,结果出现了经典的SNARC效应.实验二要求被试完成Go/No-go任务,并让被试单手(左手或右手)对奇数或偶数进行反应,结果SNARC效应没有出现,这表明认知主体的身体形式对SNARC效应产生了影响.实验三要求被试合作完成Go/No-go任务,该实验按照被试所坐的位置(左边和右边)和反应手(左手和右手),设计了四个条件,结果只有身体位置和反应手完全一致时出现了 SNARC 效应.以上结果一方面表明了具身认知观的合理性,另外一方面扩展了以往对SNARC效应本质的理解.     

Exploring the mental number line: evidence from a dual-task paradigm

In a parity-judgment task smaller numbers are responded to faster with the left-hand key and vice versa for larger numbers (SNARC effect; Dehaene et al., in Journal of Experimental Psychology: General, 122, 371-396, 1993). We used the psychological refractory period paradigm involving a parity-judgment task and tone-discrimination task to address the question at which stage this effect arises. When the parity-judgment task is performed second, then we found equal SNARC effects for the short and the long SOA. According to the central bottleneck model, this indicates that the effect arises during the response-selection or execution stage. In Experiment 2 the parity-judgment task was performed first. The pattern of results indicates that the SNARC effect originates during the perceptual encoding or response-selection. Together, our results suggest that the SNARC effect originates while the response is selected.     

Processing negative numbers by transforming negatives to positive range and by sign shortcut

Numerals are processed by a phylogenetically old analogue magnitude system. Can culturally new negative numerals be processed using this same representation? To find out whether magnitude representation could be used, we contrasted three possible processing mechanisms: an extended magnitude system for both positive and negative numbers, a mirroring mechanism that could transform negative values to the positive range to be processed on the positive magnitude system, and a sign shortcut strategy that can process the signs of numbers independently of the absolute values of numerals. To test these three hypotheses, a comparison task was used and the reaction time pattern, numerical distance, and Spatial-Numerical Association of Response Codes (SNARC) effect was analysed. The results revealed a mirroring process along with a sign shortcut mechanism. The SNARC effect was observed only when positive numbers were compared.     

Grammatical number elicits SNARC and MARC effects as a function of task demands

Despite the robustness of the spatial–numerical association of response codes (SNARC) and linguistic markedness of response codes (MARC) effect, the mechanisms that underlie these effects are still under debate. In this paper, we investigate the extraction of quantity information from German number words and nouns inflected for singular and plural using two alternative forced choice paradigms. These paradigms are applied to different tasks to investigate how access to quantity representation is modulated by task demands. In Experiment 1, we replicated previous SNARC findings for number words—that is, a relative left-hand advantage for words denoting small numbers and a right-hand advantage for words denoting large numbers in semantic tasks (parity decision and quantity comparison). No SNARC effect was obtained for surface or lexical processing tasks (font categorization and lexical decision). In Experiment 2, we found that German words inflected for singular had a relative left-hand advantage, and German words inflected for plural a relative right-hand advantage, showing a SNARC-like effect for grammatical number. The effect interfered, however, with a MARC-like effect based on the markedness asymmetry of singulars and plurals. These two effects appear to be dissociated by response latency rather than task demands, with MARC being more pronounced in early responses and SNARC being more pronounced in late responses. The present findings shed light on the relationship of conceptual number and grammatical number and constrain current accounts of the SNARC and MARC effects.     

Spatial reference frames and SNARC

In this work, the role that spatial reference frames play in determining the spatial-numerical association of response codes (SNARC) effect is examined. Participants were instructed to generate an image of the numbers 1–9 oriented spatially in either a horizontal, vertical, or proximo-distal manner. Responses to a magnitude comparison task were then provided manually using keys located either to the left and right or at the bottom and top of a computer keyboard. For conditions in which the orientation of the generated image and the response locations were orthogonally misaligned, SNARC effects were not evident. It is argued that such results imply that alignment of the spatial reference frames associated with the responses and with the representation of numerical magnitude is a necessary condition for the elicitation of the SNARC effect.     

Developing access to number magnitude: a study of the SNARC effect in 7- to 9-year-olds

The SNARC (spatial-numerical association of response codes) effect refers to the finding that small numbers facilitate left responses, whereas larger numbers facilitate right responses. The development of this spatial association was studied in 7-, 8-, and 9-year-olds, as well as in adults, using a task where number magnitude was essential to perform the task and another task where number magnitude was irrelevant. When number magnitude was essential, a SNARC effect was found in all age groups. But when number magnitude was irrelevant, a SNARC effect was found only in 9-year-olds and adults. These results are taken to suggest that (a) 7-year-olds represent number magnitudes in a way similar to that of adults and that (b) when perceiving Arabic numerals, children have developed automatic access to magnitude information by around 9 years of age.     

内源性注意和外源性注意对中小学生SNARC效应的影响

采用内源性注意和外源性注意实验范式,以判断数字奇偶为任务,材料为1～9的阿拉伯数字,考察内源性和外源性线索不同注意条件下中小学生的数字加工SNARC效应。结果发现:(1)内源性线索和外源性线索条件下,中小学生在数字加工任务中所表现出来的SNARC效应随着年龄增长逐渐增大;(2)内源性线索和外源性线索注意条件下,各年级学生均表现出显著的SNARC效应;(3)内源性线索非注意条件下,中学生能够表现出显著的SNARC效应,但小学生的SNARC效应不明显;外源性线索非注意条件下,高中生能够表现出显著的SNARC效应,但小学生和初中生的SNARC效应不明显,说明外源性注意对中小学生数字加工SNARC效应的影响比内源性注意大,且对SNARC效应的影响主要表现在较大的数字8和9上。     

The development of the SNARC effect: evidence for early verbal coding

In a recent study, Gevers and colleagues (2010, Journal of Experimental Psychology: General, Vol. 139, pp. 180-190) showed that the SNARC (spatial numerical association of response codes) effect in adults results not only from spatial coding of magnitude (e.g., mental number line hypothesis) but also from verbal coding. Because children are surrounded by rulers, number lines, and the like in the classroom, it is intuitively appealing to assume that they first use their mental number line to represent numbers and that only later in development a verbal recoding of magnitude information takes place. However, this hypothesis has never been tested. The goal of the current study was to define the developmental pattern of both accounts (spatial and verbal) in explaining the SNARC effect. To this end, 9- and 11-year-olds were tested in a magnitude comparison task. Surprisingly, clear and robust evidence for verbal coding of magnitude information was observed in both age groups. Our results imply that the ability to use verbal coding of magnitude information is robustly present early in formal schooling.     

数字SNARC效应中大小和顺序信息的分离*

分别以经度数和语言等级数为材料,采用快速刺激分类范式,通过两个实验试图分离出SNARC效应中的数字大小和顺序信息。结果发现,被试在对东经经度数的加工中存在SNARC效应,对西经经度数的加工出现反转的SNARC效应;正数组被试在汉语等级数加工中出现反转的SNARC效应,在日语等级数加工中出现SNARC效应,而负数组恰好相反。本研究表明,数字SNARC效应在大小信息和顺序信息中出现了分离,相较数字的大小信息而言,数字的顺序信息对SNARC效应影响更大。