The traditional view in cognitive science is that computations involving abstract mathematics, symbols and following multi-step rules can only be done consciously. Research has yet to demonstrate that the unconscious mind is capable of performing calculations on more than one basic abstract unit.
Although some simple arithmetic facts may be retrieved unconsciously, more complex tasks, such as understanding language, appear to require consciousness.This requirement for consciousness has been used to show that humans are uniquely capable of generating rich language and understanding abstract mathematics.
But other processes once thought to be conscious, such as learning, forming intuitions, executive functions and goal pursuit, are now understood to occur unconsciously. Research is now starting to show that the ability to understand the abstract resides in unconscious processes as well.
A recent study conducted by Asael Sklar et al. at Hebrew University shows that our unconscious mind does in fact perform operations on abstract information, which, in turn, affects how this information makes it into consciousness. Researchers used Continuous Flash Suppression (CFS) to present participants’ unconscious processes with a set of stimuli. CFS works by presenting a static stimulus to one eye while flashing a Mondrian-like image presented to the other eye. In some studies, CFS has been shown to suppress stimuli from consciousness for over three minutes.
In this experiment, the goal was to show that the meaning represented by a stimulus can affect the speed at which we become conscious of the stimulus. In the first set of trials, participants were presented with verbal expressions. Participants were instructed to press one of two keys to indicate whether stimuli appeared above or below a fixation point as soon as it broke suppression, “popping” into consciousness. Stimuli consisted of different types of three-word expressions that either were incoherent (“I ironed coffee”) or coherent (“I made coffee” or “I ironed clothes”).
In the second set of trials, the incoherent stimuli were altered so that inanimate objects were performing the action (“The bench ate a zebra”). In a third set of trials, participants were presented with verbal phrases that varied in affectivity (“black eye” versus “sand box”).
In all of these variations of stimuli, the experimenters found that incoherent phrases made it into consciousness significantly faster than coherent phrases.
In another set of trials, participants were subjected to an arithmetic priming task. Two-step mathematical equations (“9 – 3 – 4 =”) were presented as primes by means of a CFS mask. Participants were then presented with a number that was either the correct or incorrect solution to the prime, which participants were instructed to pronounce out loud.
The experimenters found that pronouncing a correct solution was facilitated by exposure to its corresponding prime. Increasing the exposure time to corresponding primes led to a decrease in the time it took for participants to answer correctly.
One possible explanation for why incoherent verbal stimuli break suppression faster is that words are only weakly associated. For example, the reason the “The window got mad at her” becomes conscious faster than “The gentleman got mad at her” because windows and getting mad are more weakly associated than gentlemen and getting mad. Another possible explanation, which the experimenters endorse, is that the entire phrase is understood and, because incoherent phrases are surprising, they break suppression faster.
But what are the limits to our unconscious abilities? Sklar et al. has argued that unconscious processes are capable of performing every fundamental computation that consciousness can perform. Cases of acquired savant syndrome, which typically emerge as the result of traumatic brain injury, furthermore suggest that everyday unconscious processes are capable of performing calculations far more sophisticated than consciousness allows.
Savants are capable of extraordinary cognitive feats yet lack the ability to explain how they able to solve complex equations, write symphonies overnight or effortlessly complete beautiful paintings. Research suggests that savants somehow gain conscious access to normally unconscious processes that are not normally accessible.
The present study lends plausibility to this explanation of savant syndrome as well as the increasingly popular belief that unconscious processes are far more sophisticated than was once thought.
Hassin RR, Sklar AY. (2012). Anything you can do: A tale of unconscious processes. In Dual Process Theories, eds Gawronski B, Sherman JW, Trope Y (Psychology Press, New York), in press.
Hassin RR, Uleman JS, Bargh JA. (2005). The New Unconscious (Oxford Univ. Press, New York).
Sklar AY, Levy N, Goldstein A, Mandel R, Maril A, Hassin R. (2012). Reading and doing arithmetic nonconsciously. PNAS.