The phenomenon of ‘conflict adaptation’ is a cognitive control function that has been thought to only apply when conscious information is used, that is, information that can be held for some time in working memory. Conflict adaptation happens in priming experiments: when a prime corresponds to the target, the target is more quickly and accurately identified but the correspondence has affects not just in its own trial but the following one, so that an incongruent prime-target produces less priming effect in the next trial. Although the priming correspondence effect applies to both conscious and unconscious primes, the conflict adaptation appeared to apply only to conscious primes. Conflict adaptation is thought to occur because following a conflict (incongruent prime-target) pre-frontal cortex control processes increase control over perceptual processes in a top-down way.

In a recent paper (see citation below), the researchers found that if attention was not relaxed between trails, the conflict adaptation could occur with unconscious priming. They used the same experiment setup as Kunde in which the priming had to be conscious to get conflict adaptation. They made only two changes: they did not use a warning sound before a trial which forced the subject to maintain vigilance between trials; and, they shortened the gap between trials to less that 1.5 seconds from about 2-2.3 seconds. Under these conditions, unconscious priming also gave conflict adaptation.

These results add to the growing body of literature suggesting that unconscious information can influence high-level (prefrontal) cognitive control functions, such as inhibitory control, task switching, error correction and conflict adaptation (present study). These results further elucidate and expand the potential influence of unconscious information on our direct, but also future decisions.

van Gaal, S., Lamme, V., & Ridderinkhof, K. (2010). Unconsciously Triggered Conflict Adaptation PLoS ONE, 5 (7) DOI: 10.1371/journal.pone.0011508