You stack the final few dishes on the sideboard, ready to be dried and put away. Your mind is elsewhere, perhaps remembering an email that still needs to be sent, or musing over plans for the weekend. At least, that is until your stray elbow silently tips a wine glass off the worktop. You watch in horror, helpless to do anything about it. Then, barely milliseconds into its descent, your hand shoots out of its own accord, saving what would have surely been a shattered mess. You only become aware of the catch when the glass is safely in your hand.
We surprise ourselves when events such as this occur. The miracle catch feels like a reflex, unbound from our inner sense of control. But if we can carry out automatic feats like this, what’s the point in being conscious in the first place? Recent experiments in neuroscience have been pushing the limits of the unconscious in order to find out. The idea is that if we find the unconscious can catch falling glasses but not understand Shakespeare, then perhaps we have found a fault line beyond which consciousness becomes useful.
Using a technique called visual masking, Hakwan Lau and Dick Passingham made a set of invisible symbols, but still left them capable of altering behaviour. The trick was to make the invisible symbol an instruction about what to do in an upcoming task. Responding to instructions is usually thought of as requiring conscious planning. However, not only did the symbols affect which task participants were preparing to carry out, they also modulated activity in the dorsolateral prefrontal cortex, a brain region traditionally associated with conscious control.
More recently, neuroscientist Simon van Gaal has been spearheading the work on the limits of the unconscious. In a recent paper reviewing his work, he outlines how visually masked stimuli can engage complex functions ranging from inhibiting one’s response to resolving conflict between competing actions. Surprisingly, he and his colleagues have yet to find anything the unconscious cannot do.
One striking thing about the miracle glass catch is that you can’t explain it to others. “I don’t know how I did that, it just happened…”. In these circumstances, we take no credit for our behaviour, and have no confidence in its causes. Chris Frith has proposed that conscious awareness gives us the ability to share our reasons for acting, and infer that others have similar reasons. Imagine a world in which every action was like the glass catch: we would be constantly surprised at ourselves, and social interactions would become meaningless. Distinguishing whether someone acted voluntarily is crucial for punishment and cooperation.
Perhaps, then, the point of being conscious is so that we can discuss, among other things, the point of being conscious!