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Background
The impact of task relevance on event-related potential amplitudes of early visual processing was previously demonstrated. Study designs, however, differ greatly, not allowing simultaneous investigation of how both degree of distraction and task relevance influence processing variations. In our study, we combined different features of previous tasks. We used a modified 1-back task in which task relevant and task irrelevant stimuli were alternately presented. The task irrelevant stimuli could be from the same or from a different category as the task relevant stimuli, thereby producing high and low distracting task irrelevant stimuli. In addition, the paradigm comprised a passive viewing condition. Thus, our paradigm enabled us to compare the processing of task relevant stimuli, task irrelevant stimuli with differing degrees of distraction, and passively viewed stimuli. EEG data from twenty participants was collected and mean P100 and N170 amplitudes were analyzed. Furthermore, a potential connection of stimulus processing and symptoms of attention deficit hyperactivity disorder (ADHD) was investigated.
Results
Our results show a modulation of peak N170 amplitudes by task relevance. N170 amplitudes to task relevant stimuli were significantly higher than to high distracting task irrelevant or passively viewed stimuli. In addition, amplitudes to low distracting task irrelevant stimuli were significantly higher than to high distracting stimuli. N170 amplitudes to passively viewed stimuli were not significantly different from either kind of task irrelevant stimuli. Participants with more symptoms of hyperactivity and impulsivity showed decreased N170 amplitudes across all task conditions. On a behavioral level, lower N170 enhancement efficiency was significantly correlated with false alarm responses.
Conclusions
Our results point to a processing enhancement of task relevant stimuli. Unlike P100 amplitudes, N170 amplitudes were strongly influenced by enhancement and enhancement efficiency seemed to have direct behavioral consequences. These findings have potential implications for models of clinical disorders affecting selective attention, especially ADHD.
Conflict Management
(2014)
Humans have a remarkable ability to plan ahead, set goals for the future and then to act accordingly. Unfortunately, this is not always the case. Everybody has experienced situations in which motivational urges like a tendency to drink another beer, or over-learned behavioral routines like driving on the right side of the road collide with ones´ goals. This tug of war between impulsive or habitual action tendencies and goal-directed actions is called a conflict.
Conflict is ubiquitous and comes in many different ways. Not surprisingly, the means to control conflict are diverse, too. Clearly, people can manage conflict in multiple ways: When expecting a conflict situation to occur in the future, one can recruit more effort to resolve the conflict, for instance by inhibiting unwanted urges or habits. Alternatively one can avoid the conflict situation and thereby circumvent possible failures to control habits and impulses. Furthermore, when currently facing a conflict, people can mobilize more effort to overcome the conflict. Alternatively they can withdraw from the conflict situation to minimize the risk of indulging in their impulses and habits.
To account for these different ways to master a conflict, the present thesis takes an initial step towards a characterization of the variability of control. To this aim, two dimensions of control will be identified that result from partially incompatible constraints on action control. These dimensions depict a trade-off between flexibility and stability and between anticipatory early selection and reactive late correction of control parameters. To describe how these control trade-offs interact and to explain how conflict is handled to ensure adaptation behavior, the conflict management framework is proposed. A corollary of this framework suggests that one strategy to control conflict comprises of a tendency to withdraw from a conflict situation.
The empirical part probed this behavioral response to conflict and tested whether participants withdraw from conflict situations. To approach this hypothesis, three series of experiments are presented that employ free choice paradigms, speeded response classification tasks and continuous movement tracking tasks to reveal withdrawal from conflict. Results show that conflict caused motivational avoidance tendencies (Experiment 1 &2), biased decision making away from conflict tasks (Experiment 3 & 5) and affected the execution of more complex courses of action (Experiment 6 & 7).
The results lend support for the proposed conflict management framework and provide the ground for a more thorough treatment of how the different conflict strategies can be integrated. As a first step, a connectionist model is presented that accounts for the simultaneous implementation of two conflict strategies observed in Experiments 3 – 5. The remainder of the present thesis analyses failures to integrate different conflict strategies. It is discussed how the conflict management framework can shed light on selected psychopathologies, inter-individual differences in control and break-downs of self-control.
Honest actions predominate human behavior. From time to time, this general preference must yield to dishonest actions, which require an effortful process of overcoming initial honest response activation. This thesis presents three experimental series to elucidate this tug-of-war between honest and dishonest response tendencies in overtly committed instances of lies, thereby joining recent efforts to move from a sheer phenomenological perspective on dishonest responding as being more difficult than honest responding to a precise description of the underlying cognitive processes. The consideration of cognitive theories, empirical evidence, and paradigms from different research fields – dishonesty, cognitive control and sensorimotor stage models of information processing – lay the groundwork for the research questions and methodological approach of this thesis.
The experiments pinpoint the underlying conflict of dishonest responding in the central, capacity-limited stage of information processing (Experiments 1 to 4), but they also demonstrate that cognitive control processes (Experiments 5 to 7) and the internalization of false alibis (Experiments 8 to 11) can reduce or even completely eliminate this conflict. The data reveals great flexibility at the cognitive basis of dishonest responding: On the one hand, dishonest responding appears to rely heavily on capacity-limited processes of response selection to overcome honest response tendencies alongside up- and downstream consequences of response activation and monitoring. On the other hand, agents have powerful tools to mitigate these effortful processes through control adaptation and false alibis. These results support and expand current theorizing of the cognitive underpinnings of dishonest responding. Furthermore, they are alerting from an applied perspective on the detection of lies, especially when considering the flexibility of even basic cognitive processes in the face of false alibis. A promising way to move forward from here would be a fine-grained discrimination of response activation, passive decay and active inhibition of honest representations in dishonest responding and the assessment of the adaptiveness of these processes.
From simply ringing a bell to preparing a five-course menu, human behavior commonly causes changes in the environment. Such episodes where an agent acts, thereby causing changes in their environment constitute the sense of agency. In this thesis four series of experi-ments elucidate how the sense of agency is represented in complex action-event sequences, thereby bridging a gap between basic cognitive research and real-life practice. It builds upon extensive research on the sense of agency in unequivocal sequences consisting of single ac-tions and distinct, predominantly auditory, outcomes. Employing implicit as well as explicit measures, the scope is opened up to multi-step sequences.
The experiments show that it is worthwhile devoting more research to complex action-event sequences. With a newly introduced auditory measure (Chapter II), common phenomena such as temporal binding and a decrease in agency ratings following distorted feedback were replicated in multi-step sequences. However, diverging results between traditional implicit and explicit measures call for further inspection. Multisensory integration appears to gain more weight when multiple actions have to be performed to attain a goal leading to more accurate representations of the own actions (Chapter III). Additionally, freedom of choice (Chapter III) as well as early spatial ambiguity altered the perceived timing of outcomes, while late spatial ambi-guity (Chapter IV) and the outcome’s self-relevance did not (Chapter V). The data suggests that the cognitive system is capable of representing multi-step action-event sequences implicitly and explicitly. Actions and sensory events show a temporal attraction stemming from a bias in the perception of outcomes. Explicit knowledge about causing an event-sequence facilitates neither feelings of control nor taking authorship. The results corroborate current theorizing on the un-derpinnings of temporal binding and the divergence between traditional implicit and explicit measures of the sense of agency. Promising avenues for further research include structured analyses of how much inferred causality contributes to implicit and explicit measures of agency as well as finding alternative measures to capture conceptual as well as non-conceptual facets of the agency experience with one method.
Cognitive control is what makes goal-directed actions possible. Whenever the environment or our impulses strongly suggests a response that is incompatible with our goals, conflict arises. Such conflicts are believed to cause negative affect. Aversive consequences of conflict may be registered in a conflict monitoring module, which subsequently initiates attentional changes and action tendencies to reduce negative affect. This association suggests that behavioral adaptation might be a reflection of emotion regulation. The theoretical cornerstone of current research on emotion regulation is the process model of emotion regulation, which postulates the regulation strategies situation selection, situation modification, attentional deployment, cognitive change, and response modulation. Under the assumption that conflict adaptation and affect regulation share common mechanisms, I derived several predictions regarding cognitive control from the process model of emotion regulation and tested them in 11 experiments (N = 509). Participants engaged in situation selection towards conflict, but only when they were explicitly pointed to action-outcome contingencies (Experiments 1 to 3). I found support for a mechanism resembling situation modification, but no evidence for a role of affect (Experiments 4 to 10). Changing the evaluation of conflict had no impact on the extent of conflict adaptation (Experiment 11). Overall, there was evidence for an explicit aversiveness of cognitive conflict, but less evidence for implicit aversiveness, suggesting that conflict may trigger affect regulation processes, particularly when people explicitly have affect regulation goals in mind.