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Modulation of sensorimotor rhythms (SMR) was suggested as a control signal for brain-computer interfaces (BCI). Yet, there is a population of users estimated between 10 to 50% not able to achieve reliable control and only about 20% of users achieve high (80–100%) performance. Predicting performance prior to BCI use would facilitate selection of the most feasible system for an individual, thus constitute a practical benefit for the user, and increase our knowledge about the correlates of BCI control. In a recent study, we predicted SMR-BCI performance from psychological variables that were assessed prior to the BCI sessions and BCI control was supported with machine-learning techniques. We described two significant psychological predictors, namely the visuo-motor coordination ability and the ability to concentrate on the task. The purpose of the current study was to replicate these results thereby validating these predictors within a neurofeedback based SMR-BCI that involved no machine learning.Thirty-three healthy BCI novices participated in a calibration session and three further neurofeedback training sessions. Two variables were related with mean SMR-BCI performance: (1) a measure for the accuracy of fine motor skills, i.e., a trade for a person’s visuo-motor control ability; and (2) subject’s “attentional impulsivity”. In a linear regression they accounted for almost 20% in variance of SMR-BCI performance, but predictor (1) failed significance. Nevertheless, on the basis of our prior regression model for sensorimotor control ability we could predict current SMR-BCI performance with an average prediction error of M = 12.07%. In more than 50% of the participants, the prediction error was smaller than 10%. Hence, psychological variables played a moderate role in predicting SMR-BCI performance in a neurofeedback approach that involved no machine learning. Future studies are needed to further consolidate (or reject) the present predictors.
Humans form impressions of others by associating persons (faces) with negative or positive social outcomes. This learning process has been referred to as social conditioning. In everyday life, affective nonverbal gestures may constitute important social signals cueing threat or safety, which therefore may support aforementioned learning processes. In conventional aversive conditioning, studies using electroencephalography to investigate visuocortical processing of visual stimuli paired with danger cues such as aversive noise have demonstrated facilitated processing and enhanced sensory gain in visual cortex. The present study aimed at extending this line of research to the field of social conditioning by pairing neutral face stimuli with affective nonverbal gestures. To this end, electro-cortical processing of faces serving as different conditioned stimuli was investigated in a differential social conditioning paradigm. Behavioral ratings and visually evoked steady-state potentials (ssVEP) were recorded in twenty healthy human participants, who underwent a differential conditioning procedure in which three neutral faces were paired with pictures of negative (raised middle finger), neutral (pointing), or positive (thumbs-up) gestures. As expected, faces associated with the aversive hand gesture (raised middle finger) elicited larger ssVEP amplitudes during conditioning. Moreover, theses faces were rated as to be more arousing and unpleasant. These results suggest that cortical engagement in response to faces aversively conditioned with nonverbal gestures is facilitated in order to establish persistent vigilance for social threat-related cues. This form of social conditioning allows to establish a predictive relationship between social stimuli and motivationally relevant outcomes.
Objective: The aim of this longitudinal study was to identify predictors of instantaneous well-being in patients with amyotrophic lateral sclerosis (ALS). Based on flow theory well-being was expected to be highest when perceived demands and perceived control were in balance, and that thinking about the past would be a risk factor for rumination which would in turn reduce well-being.
Methods: Using the experience sampling method, data on current activities, associated aspects of perceived demands, control, and well-being were collected from 10 patients with ALS three times a day for two weeks.
Results: Results show that perceived control was uniformly and positively associated with well-being, but that demands were only positively associated with well-being when they were perceived as controllable. Mediation analysis confirmed thinking about the past, but not thinking about the future, to be a risk factor for rumination and reduced well-being.
Discussion: Findings extend our knowledge of factors contributing to well-being in ALS as not only perceived control but also perceived demands can contribute to well-being. They further show that a focus on present experiences might contribute to increased well-being.
The subjective experience of controlling events in the environment alters the perception of these events. For instance, the interval between one's own actions and their consequences is subjectively compressed—a phenomenon known as intentional binding. In two experiments, we studied intentional binding in a social setting in which actions of one agent prompted a second agent to perform another action. Participants worked in pairs and were assigned to a “leader” and a “follower” role, respectively. The leader's key presses triggered (after a variable interval) a tone and this tone served as go signal for the follower to perform a keypress as well. Leaders and followers estimated the interval between the leader's keypress and the following tone, or the interval between the tone and the follower's keypress. The leader showed reliable intentional binding for both intervals relative to the follower's estimates. These results indicate that human agents experience a pre-reflective sense of agency for genuinely social consequences of their actions.
One of the most often used instruments for the assessment of food cravings is the Food Cravings Questionnaire (FCQ), which consists of a trait (FCQ-T; 39 items) and state (FCQ-S; 15 items) version. Scores on the FCQ-T have been found to be positively associated with eating pathology, body mass index (BMI), low dieting success and increases in state food craving during cognitive tasks involving appealing food stimuli. The current studies evaluated reliability and validity of a reduced version of the FCQ-T consisting of 15 items only (FCQ-T-r). Study 1 was a questionnaire study conducted online among students (N = 323). In study 2, female students (N = 70) performed a working memory task involving food and neutral pictures. Study 1 indicated a one-factorial structure and high internal consistency (α = 0.94) of the FCQ-T-r. Scores of the FCQ-T-r were positively correlated with BMI and negatively correlated with dieting success. In study 2, participants reported higher state food craving after the task compared to before. This increase was positively correlated with the FCQ-T-r. Hours since the last meal positively predicted food craving before the task when controlling for FCQ-T-r scores and the interaction of both variables. Contrarily, FCQ-T-r scores positively predicted food craving after the task when controlling for food deprivation and the interaction term. Thus, trait food craving was specifically associated with state food craving triggered by palatable food-cues, but not with state food craving related to plain hunger. Results indicate high reliability of the FCQ-T-r. Replicating studies that used the long version, small-to-medium correlations with BMI and dieting success could be found. Finally, scores on the FCQ-T-r predicted cue-elicited food craving, providing further support of its validity. The FCQ-T-r constitutes a succinct, valid and reliable self-report measure to efficiently assess experiences of food craving as a trait.
Recent research revealed that action video game players outperform non-players in a wide range of attentional, perceptual and cognitive tasks. Here we tested if expertise in action video games is related to differences regarding the potential of shortly presented stimuli to bias behavior. In a response priming paradigm, participants classified four animal pictures functioning as targets as being smaller or larger than a reference frame. Before each target, one of the same four animal pictures was presented as a masked prime to influence participants' responses in a congruent or incongruent way. Masked primes induced congruence effects, that is, faster responses for congruent compared to incongruent conditions, indicating processing of hardly visible primes. Results also suggested that action video game players showed a larger congruence effect than non-players for 20 ms primes, whereas there was no group difference for 60 ms primes. In addition, there was a tendency for action video game players to detect masked primes for some prime durations better than non-players. Thus, action video game expertise may be accompanied by faster and more efficient processing of shortly presented visual stimuli.
Action feedback affects the perception of action-related objects beyond actual action success
(2014)
Successful object-oriented action typically increases the perceived size of aimed target objects. This phenomenon has been assumed to reflect an impact of an actor's current action ability on visual perception. The actual action ability and the explicit knowledge of action outcome, however, were confounded in previous studies. The present experiments aimed at disentangling these two factors. Participants repeatedly tried to hit a circular target varying in size with a stylus movement under restricted feedback conditions. After each movement they were explicitly informed about the success in hitting the target and were then asked to judge target size. The explicit feedback regarding movement success was manipulated orthogonally to actual movement success. The results of three experiments indicated the participants' bias to judge relatively small targets as larger and relatively large targets as smaller after explicit feedback of failure than after explicit feedback of success. This pattern was independent of the actual motor performance, suggesting that the actors' evaluations of motor actions may bias perception of target objects in itself.
The extinction of conditioned fear depends on an efficient interplay between the amygdala and the medial prefrontal cortex (mPFC). In rats, high-frequency electrical mPFC stimulation has been shown to improve extinction by means of a reduction of amygdala activity. However, so far it is unclear whether stimulation of homologues regions in humans might have similar beneficial effects. Healthy volunteers received one session of either active or sham repetitive transcranial magnetic stimulation (rTMS) covering the mPFC while undergoing a 2-day fear conditioning and extinction paradigm. Repetitive TMS was applied offline after fear acquisition in which one of two faces (CS+ but not CS−) was associated with an aversive scream (UCS). Immediate extinction learning (day 1) and extinction recall (day 2) were conducted without UCS delivery. Conditioned responses (CR) were assessed in a multimodal approach using fear-potentiated startle (FPS), skin conductance responses (SCR), functional near-infrared spectroscopy (fNIRS), and self-report scales. Consistent with the hypothesis of a modulated processing of conditioned fear after high-frequency rTMS, the active group showed a reduced CS+/CS− discrimination during extinction learning as evident in FPS as well as in SCR and arousal ratings. FPS responses to CS+ further showed a linear decrement throughout both extinction sessions. This study describes the first experimental approach of influencing conditioned fear by using rTMS and can thus be a basis for future studies investigating a complementation of mPFC stimulation to cognitive behavioral therapy (CBT).
Oculomotor dominance in multitasking: Mechanisms of conflict resolution in cross-modal action
(2014)
In daily life, eye movement control usually occurs in the context of concurrent action demands in other effector domains. However, little research has focused on understanding how such cross-modal action demands are coordinated, especially when conflicting information needs to be processed conjunctly in different action modalities. In two experiments, we address this issue by studying vocal responses in the context of spatially conflicting eye movements (Experiment 1) and in the context of spatially conflicting manual actions (Experiment 2, under controlled eye fixation conditions). Crucially, a comparison across experiments allows us to assess resource scheduling priorities among the three effector systems by comparing the same (vocal) response demands in the context of eye movements in contrast to manual responses. The results indicate that in situations involving response conflict, eye movements are prioritized over concurrent action demands in another effector system. This oculomotor dominance effect corroborates previous observations in the context of multiple action demands without spatial response conflict. Furthermore, and in line with recent theoretical accounts of parallel multiple action control, resource scheduling patterns appear to be flexibly adjustable based on the temporal proximity of the two actions that need to be performed.
Fear conditioning is an efficient model of associative learning, which has greatly improved our knowledge of processes underlying the development and maintenance of pathological fear and anxiety. In a differential fear conditioning paradigm, one initially neutral stimulus (NS) is paired with an aversive event (unconditioned stimulus, US), whereas another stimulus does not have any consequences. After a few pairings the NS is associated with the US and consequently becomes a conditioned stimulus (CS+), which elicits a conditioned response (CR).
The formation of explicit knowledge of the CS/US association during conditioning is referred to as contingency awareness. Findings about its role in fear conditioning are ambiguous. The development of a CR without contingency awareness has been shown in delay fear conditioning studies. One speaks of delay conditioning, when the US coterminates with or follows directly on the CS+. In trace conditioning, a temporal gap or “trace interval” lies between CS+ and US. According to existing evidence, trace conditioning is not possible on an implicit level and requires more cognitive resources than delay conditioning.
The associations formed during fear conditioning are not exclusively associations between specific cues and aversive events. Contextual cues form the background milieu of the learning process and play an important role in both acquisition and the extinction of conditioned fear and anxiety. A common limitation in human fear conditioning studies is the lack of ecological validity, especially regarding contextual information. The use of Virtual Reality (VR) is a promising approach for creating a more complex environment which is close to a real life situation.
I conducted three studies to examine cue and contextual fear conditioning with regard to the role of contingency awareness. For this purpose a VR paradigm was created, which allowed for exact manipulation of cues and contexts as well as timing of events. In all three experiments, participants were guided through one or more virtual rooms serving as contexts, in which two different lights served as CS and an electric stimulus as US. Fear potentiated startle (FPS) responses were measured as an indicator of implicit fear conditioning. To test whether participants had developed explicit awareness of the CS-US contingencies, subjective ratings were collected.
The first study was designed as a pilot study to test the VR paradigm as well as the conditioning protocol. Additionally, I was interested in the effect of contingency awareness. Results provided evidence, that eye blink conditioning is possible in the virtual environment and that it does not depend on contingency awareness. Evaluative conditioning, as measured by subjective ratings, was only present in the group of participants who explicitly learned the association between CS and US.
To examine acquisition and extinction of both fear associated cues and contexts, a novel cue-context generalization paradigm was applied in the second study. Besides the interplay of cues and contexts I was again interested in the effect of contingency awareness. Two different virtual offices served as fear and safety context, respectively. During acquisition, the CS+ was always followed by the US in the fear context. In the safety context, none of the lights had any consequences. During extinction, a additional (novel) context was introduced, no US was delivered in any of the contexts. Participants showed enhanced startle responses to the CS+ compared to the CS- in the fear context. Thus, discriminative learning took place regarding both cues and contexts during acquisition. This was confirmed by subjective ratings, although only for participants with explicit contingency awareness. Generalization of fear to the novel context after conditioning did not depend on awareness and was observable only on trend level.
In a third experiment I looked at neuronal correlates involved in extinction of fear memory by means of functional magnetic resonance imaging (fMRI). Of particular interest were differences between extinction of delay and trace fear conditioning. I applied the paradigm tested in the pilot study and additionally manipulated timing of the stimuli: In the delay conditioning group (DCG) the US was administered with offset of one light (CS+), in the trace conditioning group (TCG) the US was presented 4s after CS+ offset. Most importantly, prefrontal activation differed between the two groups. In line with existing evidence, the ventromedial prefrontal cortex (vmPFC) was activated in the DCG. In the TCG I found activation of the dorsolateral prefrontal cortex (dlPFC), which might be associated with modulation of working memory processes necessary for bridging the trace interval and holding information in short term memory.
Taken together, virtual reality proved to be an elegant tool for examining human fear conditioning in complex environments, and especially for manipulating contextual information. Results indicate that explicit knowledge of contingencies is necessary for attitude formation in fear conditioning, but not for a CR on an implicit level as measured by FPS responses. They provide evidence for a two level account of fear conditioning. Discriminative learning was successful regarding both cues and contexts. Imaging results speak for different extinction processes in delay and trace conditioning, hinting that higher working memory contribution is required for trace than for delay conditioning.
Albeit research on brain-computer interfaces (BCI) for controlling applications has expanded tremendously, we still face a translational gap when bringing BCI to end-users. To bridge this gap, we adapted the user-centered design (UCD) to BCI research and development which implies a shift from focusing on single aspects, such as accuracy and information transfer rate (ITR), to a more holistic user experience. The UCD implements an iterative process between end-users and developers based on a valid evaluation procedure. Within the UCD framework usability of a device can be defined with regard to its effectiveness, efficiency, and satisfaction. We operationalized these aspects to evaluate BCI-controlled applications. Effectiveness was regarded equivalent to accuracy of selections and efficiency to the amount of information transferred per time unit and the effort invested (workload). Satisfaction was assessed with questionnaires and visual-analogue scales. These metrics have been successfully applied to several BCI-controlled applications for communication and entertainment, which were evaluated by end-users with severe motor impairment. Results of four studies, involving a total of N = 19 end-users revealed: effectiveness was moderate to high; efficiency in terms of ITR was low to high and workload low to medium; depending on the match between user and technology, and type of application satisfaction was moderate to high. The here suggested evaluation metrics within the framework of the UCD proved to be an applicable and informative approach to evaluate BCI controlled applications, and end-users with severe impairment and in the locked-in state were able to participate in this process.
Background: Food craving refers to an intense desire to consume a specific food. The Food Cravings Questionnaires (FCQs) assess food cravings on a trait and a state level.
Method: The current study examined half-year retest-reliability of the Food Cravings Questionnaire-Trait-reduced (FCQ-T-r) and the Food Cravings Questionnaire-State (FCQ-S) and reports associations with current food deprivation in female students.
Results: The FCQ-T-r had higher retest-reliability (rtt = .74) than the FCQ-S (rtt = .39). Although trait food craving was correlated with state food craving, it was unaffected by current food deprivation.
Conclusions: Although state and trait food craving are interdependent, the FCQs are able to differentiate between the two. As scores of the FCQ-T-r represent a stable trait, but are also sensitive to changes in eating behavior, they may be useful for the investigation of the course of eating disorders and obesity.
Background
People with severe disabilities, e.g. due to neurodegenerative disease, depend on technology that allows for accurate wheelchair control. For those who cannot operate a wheelchair with a joystick, brain-computer interfaces (BCI) may offer a valuable option. Technology depending on visual or auditory input may not be feasible as these modalities are dedicated to processing of environmental stimuli (e.g. recognition of obstacles, ambient noise). Herein we thus validated the feasibility of a BCI based on tactually-evoked event-related potentials (ERP) for wheelchair control. Furthermore, we investigated use of a dynamic stopping method to improve speed of the tactile BCI system.
Methods
Positions of four tactile stimulators represented navigation directions (left thigh: move left; right thigh: move right; abdomen: move forward; lower neck: move backward) and N = 15 participants delivered navigation commands by focusing their attention on the desired tactile stimulus in an oddball-paradigm.
Results
Participants navigated a virtual wheelchair through a building and eleven participants successfully completed the task of reaching 4 checkpoints in the building. The virtual wheelchair was equipped with simulated shared-control sensors (collision avoidance), yet these sensors were rarely needed.
Conclusion
We conclude that most participants achieved tactile ERP-BCI control sufficient to reliably operate a wheelchair and dynamic stopping was of high value for tactile ERP classification. Finally, this paper discusses feasibility of tactile ERPs for BCI based wheelchair control.
Human risk behavior is the subject of growing research in the field of psychology as well as economics. One central topic is the influence of psychological variables on risk behavior. Studies contained in this work investigated the impact of arousal, framing and motivation on risk behavior.
Arousal can on the one hand be a temporarily stable trait and on the other hand a situation-dependent variable. We showed that low trait arousal, measured via resting heart rate, predicted risky behavior. After physical exercise, state arousal was heightened in the experiment. Participants tended to act less risky after physical exercise. Taken together, the results suggest an inverse relation of arousal and risk behavior. Most studies investigating risk behavior employ a payment method that we call pay-one method: although the gambles that are used consist of many trials, only one trial is paid out. We investigated the effect of the payment method on risk behavior by employing both the pay-one and a pay-all method, which pays out all trials, in a within-subjects design. We found that participants acted about 10% less risky in the pay-one condition compared to the pay-all condition. This result suggests that risk-aversion is over-estimated in common risk paradigms that use the pay-one method.
When we worked on a hard task before, we like to engage in a more likable task afterwards. That observation led to the general classification of tasks in want-to and have-to tasks. Our body system strives towards a balance between those two task types in the sense of a homeostasis. We assessed event-related potentials (ERPs) in a risk game that we treated as a want-to task. When participants worked on a difficult have-to task before, amplitudes of the ERP-components in the risk game were raised compared to a condition where participants worked on an easy task before. We conclude that the motivation shift towards a want-to task after a have-to task can be assessed via ERP amplitudes.
In conclusion, it was shown that arousal, framing and motivation are important psychological variables that influence risk behavior. The specific mechanisms of these influences have been investigated and discussed.
Background: Food craving refers to an intense desire to consume a specific kind of food of which chocolate is the most often craved one. It is this intensity and specificity that differentiates food craving from feelings of hunger. Although food craving and hunger often co-occur, an energy deficit is not a prerequisite for experiencing food craving, that is, it can also occur without being hungry. Food craving often precedes and predicts over- or binge eating which makes it a reasonable target in the treatment of eating disorders or obesity. One of the arguably most extensively validated measures for the assessment of food craving are the Food Cravings Questionnaires (FCQs), which measure food craving on a state (FCQ-S) and trait (FCQ-T) level. Specifically, the FCQ-S measures the intensity of current food craving whereas the FCQ-T measures the frequency of food craving experiences in general. The aims of the present thesis were to provide a German measure for the assessment of food craving and to investigate cognitive, behavioral, and physiological correlates of food craving. For this purpose, a German version of the FCQs was presented and its reliability and validity was evaluated. Using self-reports, relationships between trait food craving and dieting were examined. Cognitive-behavioral correlates of food craving were investigated using food-related tasks assessing executive functions. Psychophysiological correlates of food craving were investigated using event-related potentials (ERPs) in the electroencephalogram and heart rate variability (HRV). Possible intervention approaches to reduce food craving were derived from results of those studies.
Methods: The FCQs were translated into German and their psychometric properties and correlates were investigated in a questionnaire-based study (articles #1 & #2). The relationship between state and trait food craving with executive functioning was examined with behavioral tasks measuring working memory performance and behavioral inhibition which involved highly palatable food-cues (articles #3 & #4). Electrophysiological correlates of food craving were tested with ERPs during a craving regulation task (article #5). Finally, a pilot study on the effects of HRV-biofeedback for reducing food craving was conducted (article #6).
Results: The FCQs demonstrated high internal consistency while their factorial structure could only partially be replicated. The FCQ-T also had high retest-reliability which, expectedly, was lower for the FCQ-S. Validity of the FCQ-S was shown by positive relationships with current food deprivation and negative affect. Validity of the FCQ-T was shown by positive correlations with related constructs. Importantly, scores on the subscales of the FCQ-T were able to discriminate between non-dieters and successful and unsuccessful dieters (article #1). Furthermore, scores on the FCQ-T mediated the relationship between rigid dietary control strategies and low dieting success (article #2). With regard to executive functioning, high-calorie food-cues impaired working memory performance, yet this was independent of trait food craving and rarely related to state food craving (article #3). Behavioral disinhibition in response to high-calorie food-cues was predicted by trait food craving, particularly when participants were also impulsive (article #4). Downregulation of food craving by cognitive strategies in response to high-calorie food-cues increased early, but not later, segments of the Late Positive Potential (LPP) (article #5). Few sessions of HRV-biofeedback reduced self-reported food cravings and eating and weight concerns in high trait food cravers (article #6).
Conclusions: The German FCQs represent sound measures with good psychometric properties for the assessment of state and trait food craving. Although state food craving increases during cognitive tasks involving highly palatable food-cues, impairment of task performance does not appear to be mediated by current food craving experiences. Instead, trait food craving is associated with low behavioral inhibition in response to high-calorie food-cues, but not with impaired working memory performance. Future studies need to examine if trait food craving and, subsequently, food-cue affected behavioral inhibition can be reduced by using food-related inhibition tasks as a training. Current food craving and ERPs in response to food-cues can easily be modulated by cognitive strategies, yet the LPP probably does not represent a direct index of food craving. Finally, HRV-biofeedback may be a useful add-on element in the treatment of disorders in which food cravings are elevated. To conclude, the current thesis provided measures for the assessment of food craving in German and showed differential relationships between state and trait food craving with self-reported dieting behavior, food-cue affected executive functioning, ERPs and HRV-biofeedback. These results provide promising starting points for interventions to reduce food craving based on (1) food-cue-related behavioral trainings of executive functions, (2) cognitive craving regulation strategies, and (3) physiological parameters such as HRV-biofeedback.
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.