Reading and doing arithmetic nonconsciously

Abstract

The modal view in the cognitive and neural sciences holds that consciousness is necessary for abstract, symbolic, and rule-following computations. Hence, semantic processing of multiple-word expressions, and performing of abstract mathematical computations, are widely believed to require consciousness. We report a series of experiments in which we show that multiple-word verbal expressions can be processed outside conscious awareness and that multistep, effortful arithmetic equations can be solved unconsciously. All experiments used Continuous Flash Suppression to render stimuli invisible for relatively long durations (up to 2,000 ms). Where appropriate, unawareness was verified using both objective and subjective measures. The results show that novel word combinations, in the form of expressions that contain semantic violations, become conscious before expressions that do not contain semantic violations, that the more negative a verbal expression is, the more quickly it becomes conscious, and that subliminal arithmetic equations prime their results. These findings call for a significant update of our view of conscious and unconscious processes.nonconscious processes | automaticity | CFS T he scientific investigation of consciousness and the human unconscious is an ongoing interdisciplinary effort that is central to our understanding of the human mind. The goal is simple: to map the functions performed by nonconscious processes and the functions that are performed consciously, and to understand how these two sets of functions are implemented in the brain. The modal view in cognitive sciences associates consciousness with capabilities that are uniquely (or largely) human. Two prime examples of capabilities of this kind, which are cataloged among the greatest achievements of human culture, are complex language and abstract mathematics. It is not surprising then that the modal view holds that the semantic processing of multiple-word expressions and performing of abstract mathematical computations require consciousness (1-4). In more general terms, sequential rule-following manipulations of abstract symbols are thought to lie outside the capabilities of the human unconscious.This view has received extensive empirical support. Although numerous studies have documented processing of subliminally presented single units of meaning (e.g., a word or a number) (5-8) as well as unconscious retrieval of simple arithmetic facts (9-11), previous research has generally failed to document unconscious performance of functions that require multiple (and sequenced) rule-based operations on more than one abstract unit (12)(13)(14).[Recently, work by Ric and Muller (10) has shown that simple addition (adding two numbers with a sum that is not greater than six) can occur nonconsciously. Although addition of this sort does not require more than one operation, we find these data very encouraging in terms of the challenge that we propose here.]The present study challenges this modal view of consciousness and the unconscious. Specifically...

The importance of awareness for understanding language

“…We are grateful to the authors of Sklar et al (2012) for generously sharing their stimulus presentation scripts with us. These presented stimuli in a roughly similar fashion to ours; perhaps the most important difference was that participants did not complete a Perceptual (74) to ensure that these studies had sufficient power to detect any effect.…”

A critical reexamination of doing arithmetic nonconsciously

“…For the following reasons, we believe that it is crucial to reexamine whether the claims made by Sklar et al (2012) are fully supported by the available data. From a theoretical standpoint, the claim of Bdoing arithmetic nonconsciously^is a strong claim and, hence, demands strong evidence.…”

“…The goal of the current article is to provide a critical reexamination of the claims made by Sklar et al (2012) based on the data they collected. We do so by approaching the original data set from different angles, and we assess whether the conclusions based on the original results still hold when taking the results of these new analyses into account.…”

“…In their article, Sklar et al (2012) claimed to have shown that participants can solve complex arithmetic equations nonconsciously, i.e., in the absence of consciously perceiving the equations. Specifically, they examined whether the presentation of multistep additions and subtractions with three single-digit operands (e.g., B9 − 3 − 4 =^, B3 + 1 + 4 =^) and without the result (2 and 8, respectively) would bias the verbal enumeration of a subsequently presented, visible number.…”

“…

Abstract A recent study claimed to have obtained evidence that participants can solve invisible multistep arithmetic equations (Sklar et al, 2012). The authors used a priming paradigm in which reaction times to targets congruent with the equation's solution were responded to faster compared with incongruent ones.

…”