Abstract
The purpose of the present study is to examine sequential effects of prime-target compatibility in a response priming paradigm. In the priming task a left- or right-pointing arrow (target), requiring a speeded left or right hand response, was preceded by an arrow (prime) pointing to the same (compatible) or opposite direction (incompatible). In separate experimental sessions, the prime was either masked (subliminal), or unmasked (supraliminal) and was followed by the target either immediately or after a 150 ms delay. Average reaction times to the target were affected by compatibility, masking and delay between prime and target. With no delay between prime and target, responses to compatible trials were faster than incompatible trials (Positive Compatibility Effect, PCE), irrespective of the presence of a mask. When the target followed the prime with a 150 ms delay, a PCE was observed with unmasked primes, whereas with masked primes responses to compatible trials were slower than incompatible trials (Negative Compatibility Effect, NCE). To determine if these different compatibility effects persist across trials, we recorded series of 500 consecutive responses to randomized prime-target pairs and analyzed the sequential effects on reaction times over many lags (Wiener Kernel Analysis). We compared the sequential effects in the priming task with a baseline paradigm where no prime was presented. The results so far indicate some evidence for modulations of compatibility effects extending across several trials, with implications for mechanisms of control.