Electrophysiological activation by masked primes: Independence of prime-related and target-related activities

Haberkamp

2015

Psychological Research

Many visual illusions result from assumptions of our visual system that are based on its long-term adaptation to our visual environment. Thus, visual illusions provide the opportunity to identify and learn about these fundamental assumptions. In this paper, we investigate the Ponzo illusion. Although many previous studies researched visual processing of the Ponzo illusion, only very few considered temporal processing aspects. However, it is well known that our visual percept is modulated by temporal factors. First, we used the Ponzo illusion as prime in a response priming task to test whether it modulates subsequent responses to the longer (or shorter) of two target bars. Second, we used the same stimuli in a perceptual task to test whether the Ponzo illusion is effective for very short presentation times (12 ms). We observed considerable priming effects that were of similar magnitude as those of a control condition. Moreover, the variations in the priming effects as a function of prime-target stimulus-onset asynchrony were very similar to that of the control condition. However, when analyzing priming effects as a function of participants' response speed, effects for the Ponzo illusion increased in slower responses. We conclude that although the illusion is established rapidly within the visual system, the full integration of context information is based on more time-consuming and later visual processing.

Section: Discussionsupporting

confidence: 63%

Section: Response Priming As a Tool To Investigate The Time Course Ofmentioning

confidence: 90%

Temporal processing characteristics of the Ponzo illusion

Haberkamp

2015

Psychological Research

Advances in Cognitive Psychology

“…As a result, their responses will be delayed, and the hallmark properties of response priming may not be obtained. The same pattern can be observed when in some of the trials participants must not respond at all ( nogo condition ; see Klotz et al, 2007). We advise to block short SOAs (say, up to 100 ms) and longer SOAs (longer than 100 ms) to avoid such confounds.…”

Section: Things That Can Go Wrongsupporting

confidence: 65%

Dos and don'ts in response priming research

Schmidt¹,

Haberkamp²,

Schmidt³

2011

Response priming is a well-understood but sparsely employed paradigm in cognitive science. The method is powerful and well-suited for exploring early visuomotor processing in a wide range of tasks and research fields. Moreover, response priming can be dissociated from visual awareness, possibly because it is based on the first sweep of feedforward processing of primes and targets. This makes it a theoretically interesting device for separating conscious and unconscious vision. We discuss the major opportunities of the paradigm and give specific recommendations (e.g., tracing the time-course of priming in parametric experiments). Also, we point out typical confounds, design flaws, and data processing artifacts.

“…This was first demonstrated in the time course of lateralized readiness potentials (LRPs), which start out timelocked to the prime, first develop in the direction specified by the prime, and only later proceed in the direction specified by the actual target (Eimer & Schlaghecken, 1998;Klotz, Heumann, Ansorge, & Neumann, 2007;Leuthold & Kopp, 1998;Vath & Schmidt, 2007;. The same pattern of sequential response activation can be observed in overt response behavior, such as the kinematics of primed pointing responses (Brenner & Smeets, 2004;T.…”

Section: Motor Activation In Response Primingmentioning

confidence: 86%

Mask-triggered thrust reversal in the negative compatibility effect

Hauch

Atten Percept Psychophys

2015

Rapid motor responses to visual stimuli can involve both the activation and inhibition of motor responses. Here, we trace the early processing dynamics of response generation, examining whether activation and inhibition events form a strict sequence when elicited by sequential stimuli, as we would expect if motor events are driven by fast, stimulustriggered feedforward sweeps. We employed identical stimuli in two complementary paradigms. In response priming, responses to a target stimulus are speeded or slowed by a masked prime triggering the same or an alternative response, respectively. By prolonging the prime-target interval, the response-priming effect can reverse to form the negative compatibility effect (NCE), especially when the mask contains response-relevant features. We report two experiments in which primed pointing movements going in ten possible directions were measured with response-relevant, response-irrelevant, or no masks interleaved between the primes and targets, while selective visual attention was varied. We showed that in response priming, initial responses are controlled exclusively by the prime. In the NCE, however, even the earliest movement phase is controlled jointly by the prime, mask, and target information, and a massive force in counterdirection to the primed response reverses the priming effects specifically for slow responses. We conclude that response priming reflects a strict sequence of feedforward response activations, whereas the activation/inhibition events in the NCE are not strictly serial, but integrate information from the different stimuli over time. Even though the mask features and visual attention modulate the NCE, its major source is a mask-induced, direction-specific thrust reversal of the initial response.