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In order to unify two major theories of moral judgment, a novel task is employed which combines elements of Kohlberg´s stage theory and of the theory of information integration. In contrast to the format of Kohlberg´s moral judgment interview, a nonverbal and quantitative response which makes low demands on verbal facility was used . Moral informers differing in value, i.e. high and low, are presented. The differences in effect of those two pieces of information should be substantial for a person at that specific moral stage, but small for a person at a different stage. Hence, these differences may diagnose the person's moral stage in the simplest possible way as the two levels of each of the thoughts were about typical content of the four Kohlbergian preconventional and conventional stages. The novel task allowed additionally to measure the influence of another moral concept which was about the non-Kohlbergian moral concept of recompense. After a training phase, pairs of those thoughts were presented to allow for the study of integration and individual differences. German and Korean children, 8, 10, and 12 years in age, judged deserved punishment. The patterns of means, correlations and factor loadings showed that elements of both theories can be unified, but produced unexpected results also. Additive integration of each of the two pairs of moral informers appeared, either with two Kohlbergian moral informers or with another Kohlbergian moral informer in combination with information about recompense. Also cultural independence as well as dependence, developmental changes between 8 and 10 years, and an outstanding moral impact of recompense in size and distinctiveness were observed.
Brain–computer interfaces (BCIs) enable paralyzed patients to communicate; however, up to date, no creative expression was possible. The current study investigated the accuracy and user-friendliness of P300-Brain Painting, a new BCI application developed to paint pictures using brain activity only. Two different versions of the P300-Brain Painting application were tested: A colored matrix tested by a group of ALS-patients (n = 3) and healthy participants (n = 10), and a black and white matrix tested by healthy participants (n = 10). The three ALS-patients achieved high accuracies; two of them reaching above 89% accuracy. In healthy subjects, a comparison between the P300-Brain Painting application (colored matrix) and the P300-Spelling application revealed significantly lower accuracy and P300 amplitudes for the P300-Brain Painting application. This drop in accuracy and P300 amplitudes was not found when comparing the P300-Spelling application to an adapted, black and white matrix of the P300-Brain Painting application. By employing a black and white matrix, the accuracy of the P300-Brain Painting application was significantly enhanced and reached the accuracy of the P300-Spelling application. ALS-patients greatly enjoyed P300-Brain Painting and were able to use the application with the same accuracy as healthy subjects. P300-Brain Painting enables paralyzed patients to express themselves creatively and to participate in the prolific society through exhibitions.
Several studies have investigated the neural responses triggered by emotional pictures, but the specificity of the involved structures such as the amygdala or the ventral striatum is still under debate. Furthermore, only few studies examined the association of stimuli’s valence and arousal and the underlying brain responses. Therefore, we investigated brain responses with functional magnetic resonance imaging of 17 healthy participants to pleasant and unpleasant affective pictures and afterwards assessed ratings of valence and arousal. As expected, unpleasant pictures strongly activated the right and left amygdala, the right hippocampus, and the medial occipital lobe, whereas pleasant pictures elicited significant activations in left occipital regions, and in parts of the medial temporal lobe. The direct comparison of unpleasant and pleasant pictures, which were comparable in arousal clearly indicated stronger amygdala activation in response to the unpleasant pictures. Most important, correlational analyses revealed on the one hand that the arousal of unpleasant pictures was significantly associated with activations in the right amygdala and the left caudate body. On the other hand, valence of pleasant pictures was significantly correlated with activations in the right caudate head, extending to the nucleus accumbens (NAcc) and the left dorsolateral prefrontal cortex. These findings support the notion that the amygdala is primarily involved in processing of unpleasant stimuli, particularly to more arousing unpleasant stimuli. Reward-related structures like the caudate and NAcc primarily respond to pleasant stimuli, the stronger the more positive the valence of these stimuli is.
In order to survive, organisms avoid threats and seek rewards. Classical conditioning is a simple model to explain how animals and humans learn associations between events that allow them to predict threats and rewards efficiently. In the classical conditioning paradigm, a neutral stimulus is paired with a biologically significant event (the unconditioned stimulus – US). In virtue of this association, the neutral stimulus acquires affective motivational properties, and becomes a conditioned stimulus (CS+). Defensive responses emerge for pairings with an aversive US (e.g., pain), and appetitive responses emerge for pairing with an appetitive event (e.g., reward). It has been observed that animals avoid a CS+ when it precedes an aversive US during a training phase (CS+ US; forward conditioning); whereas they approach a CS+ when it follows an aversive US during the training phase (US CS+; backward conditioning). These findings indicate that the CS+ acquires aversive properties after a forward conditioning, whereas acquires appetitive properties after a backward conditioning. It is thus of interest whether event timing also modulates conditioned responses in such an opponent fashion in humans, who are capable of explicit cognition about the associations. For this purpose, four experiments were conducted in which a discriminative conditioning was applied in groups of participants that only differed in the temporal sequence between CS+ onset and US onset (i.e., the interstimulus interval – ISI). During the acquisition phase (conditioning), two simple geometrical shapes were presented as conditioned stimuli. One shape (CS+) was always associated with a mild painful electric shock (i.e., the aversive US) and the other one (CS-) was never associated with the shock. In a between-subjects design, participants underwent either forward or backward conditioning. During the test phase (extinction), emotional responses to CS+ and CS- were tested and the US was never presented. Additionally, a novel neutral shape (NEW) was presented as control stimulus. To assess cognitive components, participants had to rate both the valence (the degree of unpleasantness or pleasantness) and the arousal (the degree of calmness or excitation) associated with the shapes before and after conditioning. In the first study, startle responses, an ancestral defensive reflex consisting of a fast twitch of facial and body muscles evoked by sudden and intense stimuli, was measured as an index of stimulus implicit valence. Startle amplitude was potentiated in the presence of the forward CS+ whilst attenuated in the presence of the backward CS+. Respectively, the former response indicates an implicit negative valence of the CS+ and an activation of the defensive system; the latter indicated an implicit positive valence of the CS+ and an activation of the appetitive system. In the second study, the blood-oxygen level dependent (BOLD) response was measured by means of functional magnetic resonance imaging (fMRI) to investigate neural responses after event learning. Stronger amygdala activation in response to forward CS+ and stronger striatum activation in response to backward CS+ were found in comparison to CS-. These results support the notion that the defensive motivational system is activated after forward conditioning since the amygdala plays a crucial role in fear acquisition and expression. Whilst the appetitive motivational system is activated after backward conditioning since the striatum plays a crucial role in reward processing. In the third study, attentional processes underlying event learning were observed by means of steady-state visual evoked potentials (ssVEPs). This study showed that both forward and backward CS+ caught attentional resources. More specifically, ssVEP amplitude was higher during the last seconds of forward CS+ that is just before the US, but during the first seconds of backward CS+ that is just after the US. Supposedly, attentional processes were located at the most informative part of CS+ in respect to the US. Participants of all three studies rated both forward and backward CS+ more negative and arousing compared to the CS-. This indicated that event timing did not influence verbal reports similarly as the neural and behavioral responses indicating a dissociation between the explicit and implicit responses. Accordingly, dual process theories propose that human behavior is determined by the output of two systems: (1) an impulsive implicit system that works on associative principles, and (2) a reflective explicit system that functions on the basis of knowledge about facts and values. Most importantly, these two systems can operate in a synergic or antagonistic fashion. Hence, the three studies of this thesis congruently suggest that the impulsive and the reflective systems act after backward association in an antagonistic fashion. In sum, event timing may turn punishment into reward in humans even though they subjectively rate the stimulus associated with aversive events as being aversive. This dissociation might contribute to understand psychiatric disorders, like anxiety disorders or drug addiction.
The thesis deals with the question which motivation direction—approach or avoidance—is connected to the emotion relief—a positive, low-arousal emotion, which is caused by an expected or nonexpected, motive-consistent change for the better, thus caused by the absence of an aversive stimulus. Based on the idea of postulating different levels of approach avoidance motivation, the Reflective-Impulsive Model of Behavior (RIM, Strack & Deutsch, 2004) is applied to relief and approach avoidance. The RIM differentiates between an impulsive and a reflective system of information processing, with both systems working in relative independence from each other. Two central variables moderate the relation between relief and approach avoidance. The first is the psychological system in which approach avoidance is processed and assessed. Two levels of approach avoidance are distinguished: an impulsive distance orientation (distance change in relation to specific stimuli) and a reflective goal orientation (attainment of positive versus avoidance of negative end states). The second is the psychological system in which relief developed: In the impulsive system, relief develops as the affect that is conditioned to the absence of negative states; in the reflective system, relief develops as a result of goal-oriented behaviour of controlling or preventing of negative stimulation. The thesis looks at both moderators (level of approach avoidance and psychological system of development of relief) at once. The central prediction for the impulsive distance orientation is: Relief leads to an approach distance orientation (distance reduction), independent from the system in which relief develops. The central prediction for the reflective goal orientation is: Relief leads to an avoidance goal orientation (control of negative end states). This latter prediction is only made for the case when relief was caused by (develops in) the reflective system, that is by one’s own, goal-directed behaviour; it is further necessary for an avoidance goal orientation that the relief state cannot certainly reached, instead there always has to uncertainty in the control of negative states. The methodology in the thesis is based on studies of aversive conditioning. In most studies, a differentiation paradigm is applied. The impulsive relief is operationalized via a classically conditioned relief (aversive CS-), whereas the reflective relief is operationalized via an active avoidance paradigm which ensures the methodological comparability of “reflective relief” to “impulsive relief”. The predictions are as follows: Prediction A: Relief will elicit positive affective valence and an approach distance orientation. This should be true for both relief that is caused by the impulsive system and for relief that is caused by the reflective system (Experiments 2-3). Prediction B: More positive valence of relief—caused by a larger change of affective states—will elicit a stronger approach distance orientation (Experiment 4). Prediction C: Relief caused by the impulsive system will not elicit a specific goal orientation (Experiment 5). Prediction D: Uncertain self-induced relief—caused by the reflective system—will elicit an avoidance goal orientation (Experiments 6-7). In addition, Experiment 1 validated the conditioning paradigm used for the elicitation of relief. The experiments in the thesis support all predictions made in the theoretical part. The work has implications for the assumptions made in the RIM (Strack & Deutsch, 2004). In the impulsive system, the affective valence determines approach avoidance orientation (e.g., R. Neumann & Strack, 2000), the reflective goal not playing an important role. Relief elicits an approach orientation in the impulsive system. In the reflective system, the active goal is decisive for the approach avoidance orientation. Uncertain self-caused relief elicits an avoidance goal orientation in the reflective system. The studies of the thesis thus support and validate the assumptions made in the RIM (Strack & Deutsch, 2004) in the specific field of motivational direction.
Neuroplasticity is a term indicating structural and functional changes in the brain through the lifespan. In the present study, differences in the functional cortical activations between the musical talents and non-talents were investigated after a short-term practice of the visuomotor and auditory tasks. Visuomotor task consisted of the finger tapping sequences, while auditory task consisted of passive listening to the classical music excerpts. Non-talents were divided in two groups: trained non-talents who practiced the task prior to scanning and untrained non-talents who did not practice the task. Functional activations were obtained by the functional magnetic resonance imaging (fMRI) in a 1.5T Scanner. It was hypothesized that talents would exhibit different functional activations from non-talents in both tasks as a result of the long-term music practice, which would account for the brain plasticity. Decreased activation of the same areas in talents in respect to the non-talents as well as the activation of different areas between the talents and non-talents was hypothesized. In addition due to a plethora of previous studies showing increased activations in the primary motor cortex (M1) in musicians, as well as left inferior frontal gyrus (lIFG), increased activation of the M1 and lIFG in talents were hypothesized. Behavioral results did not reveal differences in performance among the three groups of subjects (talents, non-talents who practiced the task, and non-talents who did not practice the task). The main findings from imaging results of the visuomotor task confirmed the hypothesis of the increased activation in the M1 in talents. Region of interest analyses of the lIFG revealed the highest activation in the untrained non-talents, lower activation in talents, and least activation in the trained non-talents. Posthoc imaging analyses revealed higher activations in the cerebella of subjects who practiced the visuomotor task. For the auditory task, the effect of auditory practice was observed in the right inferior frontal gyrus (rIFG). These results should be interpreted with caution due to the absence of behavioral differences among the groups.
The aim of this project was to investigate whether reflex-like innate facial reactions to tastes and odors are altered in patients with eating disorders. Qualitatively different tastes and odors have been found to elicit specific facial expressions in newborns. This specificity in newborns is characterized by positive facial reactions in response to pleasant stimuli and by negative facial reactions in response to unpleasant stimuli. It is, however, unclear, whether these specific facial displays remain stable during ontogeny (1). Despite the fact that several studies had shown that taste-and odor-elicited facial reactions remain quite stable across a human’s life-span, the specificity of research questions, as well as different research methods, allow only limited comparisons between studies. Moreover, the gustofacial response patterns might be altered in pathological eating behavior (2). To date, however, the question of whether dysfunctional eating behavior might alter facial activity in response to tastes and odors has not been addressed. Furthermore, changes in facial activity might be linked to deficient inhibitory facial control (3). To investigate these three research questions, facial reactions in response to tastes and odors were assessed. Facial reactions were analyzed using the Facial Action Coding System (FACS, Ekman & Friesen, 1978; Ekman, Friesen, & Hager, 2002) and electromyography.
The aim of the present thesis was to explore how food deprivation and reward expectancy versus frustrative nonreward change implicit and explicit food-liking and food-wanting. As a result, Experiment 1-3 were successful in revealing that liking- and wanting-related associations toward food stimuli dissociate as a function of food deprivation, given that participants were not rewarded with real food during the experiment. More specifically, whereas food-deprived participants showed more wanting-related associations toward food stimuli than satiated participants, the liking-related associations did not differ across both conditions of hunger. Overall, this effect could be replicated in 3 experiments using different manipulations of nonreward versus reward expectancy. However, neither food deprivation nor nonreward were found to influence participants’ self-reported mood and frustration. Moreover, participants of Experiment 2 anticipating food consumption showed the same liking- and wanting-related responses due to food deprivation than participants in the nonreward condition. But providing participants with individual control over food consumption abolished the dissociation of liking- and wanting-related associations. In this condition, however, participants’ liking- and wanting-related associations were not moderated by need state, maybe due to the (partial) consumption of snack food before the implicit attitude assessment. This, in turn, may have reduced participants’ disposition to respond with more liking- and wanting-related associations when being hungry. Finally, Experiment 4 revealed that the presentation of need-relevant vs. need-irrelevant stimuli prompted different liking-related associations depending on the time participants had fasted before the experiment. Specifically, it could be demonstrated that whereas moderately-hungry compared to satiated participants responded with more positive associations toward need-relevant stimuli, 15 hours food-deprived participants responded with more negative associations compared to moderately-hungry and satiated participants. Respectively, a significant curvilinear function of need state was obtained. In addition, participants were found to immediately respond more negatively to need-irrelevant stimuli as soon as they became moderately hungry, evidencing devaluation effects (see Brendl, Markman, & Messner, 2003) to also occur on an implicit level of responding. Contrary to the implicit liking- and wanting-related evaluations, self-reported explicit food-liking and food-wanting did not dissociate as a function of food deprivation and nonreward, revealing that participants’ explicit self-reports of food-liking and food-wanting did not mirror their implicit responses. As the most important result, it could be demonstrated that explicit food-liking and food-wanting varied positively as a function of need state. The results were discussed on the background of different theoretical assumptions on the malleability of implicit and explicit need-relevant attitudes (e.g. motivational theories, frustrative nonreward).
Der Einfluss von Methylphenidat auf die affektive Bildverarbeitung bei erwachsenen AD(H)S Patienten
(2010)
Die vorliegende Arbeit wurde im Rahmen des ADHS-Forschungsprojektes der Universität Würzburg zur Identifikation von Endophänotypen der ADHS durchgeführt. Im Fokus des Interesses stand dabei die Untersuchung emotionaler Verarbeitungsprozesse bei erwachsenen ADHS-Patienten. Conzelmann und Kollegen (Conzelmann, et al., 2009) konnten zeigen, dass erwachsene ADHS-Patienten vom Mischtypus und vom hyperaktiv/ impulsiven Typus eine defizitäre affektive Startle Modulation aufweisen. Basierend auf diesen Ergebnissen stellte sich in der vorliegenden Arbeit die Frage, ob dieser defizitäre Schreckreflex auf emotionale Bilder des International Affective Picture Systems (IAPS) zunächst replizierbar und falls ja, durch die Einnahme eines Methylphenidatpräparats (MPH) vermindert oder gänzlich aufgehoben werden kann. Um dieser Frage nachzugehen, wurden zunächst im Rahmen einer Vorstudie 15 erwachsene ADHS-Patienten (Mischtypus) aus der Studie von Conzelmann et al. (2009) nach einer Zeitspanne von einem bis zwei Jahren ein weiteres Mal getestet. Etwa eine Stunde vor der zweiten Testung erhielten die Patienten die Instruktion, ihr MPH-Präparat einzunehmen. Im Anschluss daran wurden den Patienten positive, neutrale und negative IAPS-Bilder präsentiert. Diese Bilddarbietung wurde in unregelmäßigen Abständen von einem akustischen Störgeräusch unterbrochen, den die Patienten möglichst ignorieren sollten. Im zweiten Teil der Untersuchung wurden die Probanden sowohl während der ersten als auch während der zweiten Testung angewiesen, die einzelnen Bilder hinsichtlich ihrer Valenz (angenehm versus unangenehm) und ihres Arousals (aufregend versus ruhig) zu bewerten. Von den 15 getesteten Patienten konnten 13 in die Auswertung mit einbezogen werden (2 Patienten hatten unzureichend auf den Ton reagiert). Unterschiede zwischen den beiden Testzeitpunkten (also ohne und mit MPH) konnten bezüglich der affektiven Startle Modulation lediglich auf Bilder mit hohem Arousal festgestellt werden. Für diese spezifischen Stimuli zeigten die Patienten ohne MPH keine verringerte Startle Reaktion während der Betrachtung positiver Bilder. Mit MPH konnte dieses Ausbleiben der Startle Attenuation aufgehoben werden. Anders als bei der affektiven Startle Modulation, konnte bei den zusätzlich erhobenen physiologischen Maßen weder ein systematischer Einfluss durch die IAPS-Bilder noch durch die Medikation festgestellt werden. Gleiches ließ sich bei den Valenz- und Arousalratings feststellen. Ob sich diese positive MPH-Wirkung auf die affektive Startle Modulation auch unabhängig vom Arousalgehalt der betrachteten Bilder zeigt, sollte im Anschluss an diese Vortestung mittels einer zusätzlichen Studie mit wesentlich größerem Stichprobenumfang untersucht werden. Die Hauptstudie wurde sowohl doppelblind als auch placebo-kontrolliert und im cross-over Design durchgeführt. Die Testprozedur am Computer war vergleichbar mit dem Ablauf der Vortestung. Im Rahmen der Hauptstudie wurden 71 AD(H)S-Patienten (60 vom Mischtypus, 11 vom vorwiegend unaufmerksamen Typus) zweimal getestet. Von diesen 71 Patienten konnten letztlich 61 in die Auswertung der Haupttestung mit einbezogen werden (ein ADHS-Patient (Mischtypus) kam zur zweiten Testung nicht und 9 ADHS-Patienten (Mischtypus) hatten unzureichend auf den Startle-Ton reagiert). Dabei konnte zunächst für die Bilder mit hohem Arousal die defizitäre Startle Modulation auf positive Bilder repliziert werden. Durch die MPH-Einnahme ließ sich dieses Defizit jedoch nicht beheben. Da Conzelmann et al. (2009) lediglich beim Mischtypus und hyperaktiv-impulsiven Typus eine defizitäre Startle Modulation nachweisen konnten, wurde eine vergleichbare Auswertung für die Subgruppe der 51 ADHS-Patienten vom Mischtypus durchgeführt. Dabei unterschieden sich die Ergebnisse dieser Subgruppe im Wesentlichen nicht von der Gesamtstichprobe. Auch bei der Überprüfung der genetischen Hypothesen ließ sich keine Interaktion zwischen der Medikation und dem DRD4-7r, dem COMT Val/Met und dem DAT1-10r Polymorphismus feststellen. Die Ergebnisse zeigen zum einen eine defizitäre Startle Modulation der 61 AD(H)S-Patienten, die vergleichbar ist mit dem gezeigten Defizit von Conzelmann et al. (2009) bei Patienten des Mischtypus. Ein positiver Effekt durch die MPH-Einnahme konnte dabei ebenso wenig bestätigt werden wie eine mögliche Interaktion verschiedener dopaminerger Genpolymorphismen auf die MPH-Wirkung. Zusätzliche Studien werden zeigen, ob diese defizitäre Verarbeitung tatsächlich durch die MPH-Einnahme unbeeinflusst bleibt oder ob letztlich mittels medikamentöser Interventionen doch noch eine entsprechende Symptomverbesserung bei erwachsenen AD(H)S-Patienten zu erzielen ist.