Robert Wirth

Thinking with portals: Revisiting kinematic cues to intention

What we intend to achieve with our actions affects the way we move our body. This has been repeatedly shown for both, movement-related intentions such as grasping and turning an object, and relatively high-level intentions such as the intention to collaborate or to compete with a social partner. The impact of an intermediate level of intentions - referring to action-contingent changes in the physical environment - is far less clear, however. We present three experiments that aim at scrutinizing this level of analysis by showing how such anticipated consequences affect movement trajectories. Participants steered a virtual avatar toward portals that displaced the avatar to a different but predictable location. Even though this displacement occurred only after the movement was completed, hand movements were clearly torn toward the anticipated final location of the avatar. These results show that properties of anticipated action consequences leave a fingerprint on movement trajectories and provide an opportunity to unite previous accounts on the relation of intentions and movements with general frameworks of action planning.

Pushing the rules: effects and aftereffects of deliberate rule violations

Most of our daily life is organized around rules and social norms. But what makes rules so special? And what if one were to break a rule intentionally? Can we simply free us from the present set of rules or do we automatically adhere to them? How do rule violations influence subsequent behavior? To investigate the effects and aftereffects of violating simple S-R rule, we conducted three experiments that investigated continuous finger-tracking responses on an iPad. Our experiments show that rule violations are distinct from rule-based actions in both response times and movement trajectories, they take longer to initiate and execute, and their movement trajectory is heavily contorted. Data not only show differences between the two types of response (rule-based vs. violation), but also yielded a characteristic pattern of aftereffects in case of rule violations: rule violations do not trigger adaptation effects that render further rule violations less difficult, but every rule violation poses repeated effort on the agent. The study represents a first step towards understanding the signature and underlying mechanisms of deliberate rule violations, they cannot be acted out by themselves, but require the activation of the original rule first. Consequently, they are best understood as reformulations of existing rules that are not accessible on their own, but need to be constantly derived from the original rule, with an add-on that might entail an active tendency to steer away from mental representations that reflect (socially) unwanted behavior.

Asymmetric transfer effects between cognitive and affective task disturbances

Task-irrelevant features of a stimulus can disturb performance on a given task, and this can occur for cognitive reasons such as irrelevant stimulus position, and affective reasons such as high stimulus valence. The human brain adapts to such disturbances in order to ensure successful task performance. Adaptations can occur in a transient manner in response to recent events, and they can also be sustained to account for overall probabilities of disturbances. Here, we study the mutual interplay between affective and cognitive task disturbances under conditions of sustained conflict adaptation. More precisely, we examined the trajectory of finger movements in a speeded classification task and investigated whether adaptation to a high probability of spatial disturbances transfers to the impact of affective disturbances (Experiment 1) and whether adaptation to a high probability of affective disturbances transfers to the impact of spatial disturbances (Experiment 2). Our observations point towards an asymmetric transfer from adaptation to affective onto the processing of cognitive disturbances, but not the other way around.

Stroking me softly: Body-related effects in effect-based action control

Empirical investigations of ideomotor effect anticipations have mainly focused on action effects in the environment. By contrast, action effects that apply to the agent’s body have rarely been put to the test in corresponding experimental paradigms. We present a series of experiments using the response–effect compatibility paradigm, in which we studied the impacts of to-be-produced tactile action effects on action selection, initiation, and execution. The results showed a robust and reliable impact if these tactile action effects were rendered task-relevant (Exp. 1), but not when they were task-irrelevant (Exps. 2a and 2b). We further showed that anticipations of tactile action effects follow the same time course as anticipations of environment-related effects (Exps. 3 and 4). These findings demonstrate that body-related action effects affect action control much as environment-related effects do, and therefore support the theoretical assumption of the functional equivalence of all types of action effects.

Effect Monitoring in Dual-Task Performance.

Actions aim to produce effects in the environment. To accomplish this properly, we not only have to recruit the appropriate motor patterns, but also we must be able to monitor whether an intended effect has ultimately been realized. Here, we investigated the impact of such effect monitoring on performance in multitasking situations: Multitasking basically means to produce and monitor multiple actions and effects in fast succession. We show that effect monitoring cannot run in parallel, without causing processing decrements, with a second task. Also, monitoring of effects that are spatially incompatible to a response seems to take longer than the monitoring of spatially compatible action effects (Experiments 1 through 4). We further argue that effect monitoring is essential toward learning of response-effect associations, as it captures not only anticipated action effects, but also unpredictable occurrences in the environment (Experiments 5a and 5b).

The dishonest mind set in sequence

Dishonest responding is an important part of the behavioral repertoire and perfectly integrated in communication and daily actions. Thus, previous research aimed at uncovering the cognitive mechanisms underlying dishonest responding by studying its immediate behavioral effects. A comprehensive account of the aftereffects of this type of behavior has not been presented to date, however. Based on the methods and theories from research on task switching, we, therefore, explored the notion of honest and dishonest responding as two distinct intentional sets. In four experiments, participants responded either honestly or dishonestly to simple yes/no questions. Crucially, robust switch costs were found between honest and dishonest responding when questions succeeded promptly (Exp. 1) but also when an unrelated task intervened between questions (Exp. 2). Surprisingly, responding dishonestly to a question also affected responses in the subsequent intervening task in terms of a more liberal response criterion. Time to prepare for the upcoming intentional set further induced asymmetrical switch costs (Exp. 3). Finally, a novel control condition (Exp. 4) allowed us to pinpoint most of the observed effects to negation processing as an inherent mechanism of dishonesty. The experiments shed new light on the cognitive mechanisms underlying dishonesty by providing strong support for the concept of distinct mental sets for honest and dishonest responding. The experiments further reveal that these mental sets are notably stable and are not disturbed by intervening task performance. The observed aftereffects of dishonest responding might also provide a potent extension to applied protocols for lie detection.

The electrophysiological signature of deliberate rule violations.

Humans follow rules by default, and violating even simple rules induces cognitive conflict for the rule breaker. Previous studies revealed this conflict in various behavioral measures, including response times and movement trajectories. Based on these experiments, we investigated the electrophysiological signature of deliberately violating a simple stimulus-response mapping rule. Such rule violations were characterized by a delayed and attenuated P300 component when evaluating a rule-relevant stimulus, most likely reflecting increased response complexity. This parietal attenuation was followed by a frontal positivity for rule violations relative to correct response trials. Together, these results reinforce previous findings on the need to inhibit automatic S-R translation when committing a rule violation, and they point toward additional factors involved in rule violation. Candidate processes such as negative emotional responses and increased monitoring should be targeted by future investigations.

Smooth criminal: convicted rule-breakers show reduced cognitive conflict during deliberate rule violations

Classic findings on conformity and obedience document a strong and automatic drive of human agents to follow any type of rule or social norm. At the same time, most individuals tend to violate rules on occasion, and such deliberate rule violations have recently been shown to yield cognitive conflict for the rule-breaker. These findings indicate persistent difficulty to suppress the rule representation, even though rule violations were studied in a controlled experimental setting with neither gains nor possible sanctions for violators. In the current study, we validate these findings by showing that convicted criminals, i.e., individuals with a history of habitual and severe forms of rule violations, can free themselves from such cognitive conflict in a similarly controlled laboratory task. These findings support an emerging view that aims at understanding rule violations from the perspective of the violating agent rather than from the perspective of outside observer.

The role of feedback delay in dual-task performance

Doing two things at once is hard, and it is probably hard for various reasons. Here we aim to demonstrate that one so far barely considered reason is the monitoring of sensory action feedback, which detracts from processing of other concurrent tasks. To demonstrate this, we engaged participants in a psychological refractory period paradigm. The responses in the two tasks produced visual action effects. These effects occurred either immediately or they were delayed for the first of the two responses. We assumed that delaying these effects would engage a process of monitoring visual feedback longer, and delay a concurrent task more, as compared to immediate effects. This prediction was confirmed in two experiments. We discuss the reasons for feedback monitoring and its possible contribution to dual tasking.

Long-term and short-term action-effect links and their impact on effect monitoring.

People aim to produce effects in the environment, and according to ideomotor theory, actions are selected and executed via anticipations of their effects. Further, to ensure that an action has been successful and an effect has been realized, we must be able to monitor the consequences of our actions. However, action-effect links might vary between situations, some might apply for a majority of situations, while others might only apply to special occasions. With a combination of behavioral and electrophysiological markers, we show that monitoring of self-produced action effects interferes with other tasks, and that the length of effect monitoring is determined by both, long-term action-effect links that hold for most situations, and short-term action-effect links that emerge from a current setting. Effect monitoring is fast and frugal when these action-effect links allow for valid anticipation of action effects, but otherwise effect monitoring takes longer and delays a subsequent task. Specific influences of long-term and short-term links on the P1/N1 and P3a further allow to dissect the temporal dynamics of when these links interact for the purpose of effect monitoring.