Mask‐ and distractor‐triggered inhibitory processes in the priming of motor responses: An EEG study

Abstract

Masked stimuli presented near the threshold of conscious awareness may act as primes, affecting responses to subsequent targets. With arrows as primes and targets, the prime-mask-target sequence has been shown to evoke triphasic lateralized readiness potentials (LRP) with two phases of imbalance between hemispheres preceding the target-related contralateral preponderance of negativity: first a negative, then a positive preponderance contralateral to prime direction. The present article provides evidence that the second wave is related to mask presentation and reflects inhibitory processing independent of reductions in prime visibility, even being evoked by nonmasking distractors that leave the prime fully accessible for consciousness. Of all hypotheses put forward to account for inverse effects in masked priming, this finding is most compatible with the mask-triggered inhibition hypothesis suggested by P. Jaśkowski (2007).

The reversal of perceptual and motor compatibility effects differs qualitatively between metacontrast and random-line masks

“…Two main theories have been proposed to explain the NCE. The motor inhibition theory considers that the NCE is caused by an inhibitory mechanism in the motor system, which suppresses the initial premature motor activation evoked by the prime (Eimer, 1999;Jaśkowski, 2008;Jaśkowski et al, 2008;Jaśkowski & PrzekorackaKrawczyk, 2005;Jaśkowski & Verleger, 2007;Schlaghecken & Eimer, 2000. This theory holds that the origin of the NCE is purely motor and can be demonstrated when masks do not share perceptual features with their primes.…”

“…While the self-generated motor inhibition hypothesis provides a plausible account of the NCE when the prime is strongly masked, it does not provide a convincing explanation of the origin of the NCE. Several studies have shown that the NCE occurs even if the primes were not effectively masked; suggesting that suppression of perceptual evidence by the mask is unlikely to be the cause of the NCE (Jaśkowski, 2008;Jaśkowski et al, 2008;Jaśkowski & Przekoracka-Krawczyk, 2005;Jaśkowski & Verleger, 2007). For instance, NCEs have been observed when random-line mask stimuli were presented after the prime but not in the same location, so that the prime was perfectly visible (e.g., Jaśkowski, 2008).…”

“…In such cases, the NCE is likely to be the result of Motor Inhibitory Mechanisms (Eimer, 1999;Jaśkowski, 2008;Jaśkowski, Bialunska, Tomanek, & Verleger, 2008;Jaśkowski & Przekoracka-Krawczyk, 2005;Jaśkowski & Verleger, 2007;Schlaghecken & Eimer, 2000. According to this account, the NCE is caused by an inhibitory mechanism in the motor system which suppresses the initial premature motor activation evoked by the prime.…”

The availability of attentional resources modulates the inhibitory strength related to weakly activated priming

“…An alternative view of the NCE inhibitory mechanism was suggested by Jaśkowski and colleagues (Jaśkowski, 2007(Jaśkowski, , 2008a(Jaśkowski, , b, 2009Jaśkowski, Białuńska, Tomanek, & Verleger, 2008;Jaśkowski & Przekoracka-Krawczyk, 2005;Jaśkowski & Slósarek, 2007;Jaśkowski & Verleger, 2007;Verleger, Jaśkowski, Aydemir, van der Lubbe, & Groen, 2004), who proposed the mask-triggered inhibition (MTI) hypothesis. This hypothesis assumes that perceptual interactions between the prime and the mask can produce inverse priming effects.…”

“…Both studies of the NCE and other studies have suggested that inhibitory processes are usually automatic and do not require attention, regardless of their involvement in subliminal masked priming (i.e., unconscious priming; see, Eimer & Schlaghecken, 1998Eysenck, 1984;Ohman & Soares, 1994;Ocampo & Finkbeiner, 2013;Posner & Snyder, 1975;Schlaghecken et al, 2007;Schneider & Shiffrin, 1977), of the presence of flanked priming (i.e., weakly activated priming, which is elicited by the presentation of primes for a relatively short time (e.g., 50 ms or 20 ms) followed by the presentation of distractors or short masks (e.g., 80 ms or 50 ms in Wang, Zhao, Liu, Wei, & Di, 2014); see, Bennett, Lleras, Oriet, & Enns, 2007;Jaśkowski, 2007Jaśkowski, , 2008aJaśkowski, , b, 2009Jaśkowski et al, 2008;Jaśkowski & Verleger, 2007;Lleras & Enns, 2006), or even of the absence of backward masking (i.e., relatively strong activated priming; see, Vainio, 2009Vainio, , 2011Vainio & Mustonen, 2011). In particular, Vainio (2011) suggested that when motor activation is triggered by naturalistic objects, it can be automatically inhibited in the absence of backward masking, even when the object does not contain any task-relevant features.…”