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ABSTRACT: The burgeoning field of social neuroscience has begun to illuminate the complex biological bases of human social cogni-tive abilities. However, in spite of being based on the premise of investigating the neural bases of interacting individuals, a major-ity of studies has focused on studying brains in isolation using paradigms that investigate "offline" social cognition, i.e., social cognition from an observer's point of view, rather than "online" social cognition, i.e., social cognition from an interactor's point of view. Consequently, the neural correlates of real-time social inter-action have remained largely elusive and may—paradoxically— be seen to represent the "dark matter" of social neuroscience (Schilbach et al., 2013). More recently, a growing number of researchers have begun to study social cognition from an interactor's point of view, based on the assumption that there is something fundamentally different when we are actively engaged with others in real-time social inter-action as compared to when we merely observe them. Whereas for "offline" social cognition, interaction and feedback are merely a way of gathering data about the other person that feeds into pro-cessing algorithms "inside" the agent, it has been proposed that in "online" social interaction the knowledge of the other—at least in part—may reside in the interaction dynamics "between" the agents. Furthermore, being a participant in an interaction may entail a commitment toward being responsive created by impor-tant difference in the motivational foundations of "online" and "offline" social cognition. There are at least three different axes along which social neu-roscience will have to evolve in order to (a) be able to validate the idea that interaction is more than just an online recruitment of essentially two or more agents' internal social knowledge, and (b) move toward a true understanding of what it is like to exist and function in a social context. In a recent paper (Schilbach et al., 2013; see Figure 1), we describe one axis representing detachment versus emotional engagement; a second axis that runs from purely spectatorial setups to setups that allow par-ticipants to produce a meaningful change in their environment, to paradigms in which two agents can interact with each other in a dynamic way; and a third axis that contrasts methodolo-gies that look for explanatory variance within a single agent with approaches focusing on explanatory power of a system of multi-ple agents. It is important to note that a more enactive approach that incorporates meaningful interaction need not necessarily focus exclusively on dynamic components of ongoing interaction. For instance, establishing the degree to which "passive" social perception and related biobehavioral markers change when in interaction as compared to merely observing, or the study of how we perceive cooperative interaction and adapt to it, is extremely useful and necessary in order to come to a full understanding of social interaction. In this line of thought, this Frontiers Research Topic brings together contributions from researchers in social neuroscience and related fields, whose work contributes to the development of the neuroscientific investigation of "online" social cognition and draws upon behavioral studies, psychophysiological investi-gations, computational approaches, developmental, and patient studies while also providing theoretical contributions that can help to advance research in social neuroscience. This creates an interdisciplinary perspective on what it is that separates "online" from "offline" social cognition and how differences in the underlying neurobiological processes and mechanisms can be investigated. The contributions highlight the importance of methodological advances to quantify the interpersonal processes of real-time social interaction and demonstrate how this can be related to measurements obtained from one or two brains. Without going into each of the 52 contributions to this Research Topic, there are a number of emerging patterns com-ing to the foreground. All of them, to some degree, focus on at least one aspect of the three axes and try to find an explana-tion of behavioral variance that cannot be found by exclusively focusing on disengaged agents—be it in engagement, active par-ticipation in joint actions, or in the interaction dynamics itself. The theoretical contributions shed light on how recent findings might reveal the crucial and subtle differences between spectato-rial versus interactionist social cognition. Moreover, they suggest various ways of conceptualizing this distinction by focusing on coordination dynamics or interactive alignment/synchronization, cooperation, intentionality, brain-computer interfaces, differen-tial involvement of (conscious) top-down processes, and more implicit, automatic processing, or by pointing toward findings in developmental neuroscience. Among the original research articles, a number focus on neural correlates of some form of live social interaction, either face-to-face, or via gaze and joint attention, joint action in various dual tasks such as imitation, behavioral or listener-speaker cou-pling. These are not limited to investigating only single agents' neural correlates, but also look at the coupling of participants' neural correlates within an interactive setup. The field of interest pertaining to the nature of interaction stretches far beyond that and incorporates inquiries into risk-taking, inequity, deception— often in the context of games, emotion, and face perception, machine interaction, the role of oxytocin, and specific interaction deficits in persons with autism.
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[show abstract]
[hide abstract]
ABSTRACT: The burgeoning field of social neuroscience has begun to illuminate the complex biological bases of human social cogni-tive abilities. However, in spite of being based on the premise of investigating the neural bases of interacting individuals, a major-ity of studies has focused on studying brains in isolation using paradigms that investigate "offline" social cognition, i.e., social cognition from an observer's point of view, rather than "online" social cognition, i.e., social cognition from an interactor's point of view. Consequently, the neural correlates of real-time social inter-action have remained largely elusive and may—paradoxically— be seen to represent the "dark matter" of social neuroscience (Schilbach et al., 2013). More recently, a growing number of researchers have begun to study social cognition from an interactor's point of view, based on the assumption that there is something fundamentally different when we are actively engaged with others in real-time social inter-action as compared to when we merely observe them. Whereas for "offline" social cognition, interaction and feedback are merely a way of gathering data about the other person that feeds into pro-cessing algorithms "inside" the agent, it has been proposed that in "online" social interaction the knowledge of the other—at least in part—may reside in the interaction dynamics "between" the agents. Furthermore, being a participant in an interaction may entail a commitment toward being responsive created by impor-tant difference in the motivational foundations of "online" and "offline" social cognition. There are at least three different axes along which social neu-roscience will have to evolve in order to (a) be able to validate the idea that interaction is more than just an online recruitment of essentially two or more agents' internal social knowledge, and (b) move toward a true understanding of what it is like to exist and function in a social context. In a recent paper (Schilbach et al., 2013; see Figure 1), we describe one axis representing detachment versus emotional engagement; a second axis that runs from purely spectatorial setups to setups that allow par-ticipants to produce a meaningful change in their environment, to paradigms in which two agents can interact with each other in a dynamic way; and a third axis that contrasts methodolo-gies that look for explanatory variance within a single agent with approaches focusing on explanatory power of a system of multi-ple agents. It is important to note that a more enactive approach that incorporates meaningful interaction need not necessarily focus exclusively on dynamic components of ongoing interaction. For instance, establishing the degree to which "passive" social perception and related biobehavioral markers change when in interaction as compared to merely observing, or the study of how we perceive cooperative interaction and adapt to it, is extremely useful and necessary in order to come to a full understanding of social interaction. In this line of thought, this Frontiers Research Topic brings together contributions from researchers in social neuroscience and related fields, whose work contributes to the development of the neuroscientific investigation of "online" social cognition and draws upon behavioral studies, psychophysiological investi-gations, computational approaches, developmental, and patient studies while also providing theoretical contributions that can help to advance research in social neuroscience. This creates an interdisciplinary perspective on what it is that separates "online" from "offline" social cognition and how differences in the underlying neurobiological processes and mechanisms can be investigated. The contributions highlight the importance of methodological advances to quantify the interpersonal processes of real-time social interaction and demonstrate how this can be related to measurements obtained from one or two brains. Without going into each of the 52 contributions to this Research Topic, there are a number of emerging patterns com-ing to the foreground. All of them, to some degree, focus on at least one aspect of the three axes and try to find an explana-tion of behavioral variance that cannot be found by exclusively focusing on disengaged agents—be it in engagement, active par-ticipation in joint actions, or in the interaction dynamics itself. The theoretical contributions shed light on how recent findings might reveal the crucial and subtle differences between spectato-rial versus interactionist social cognition. Moreover, they suggest various ways of conceptualizing this distinction by focusing on coordination dynamics or interactive alignment/synchronization, cooperation, intentionality, brain-computer interfaces, differen-tial involvement of (conscious) top-down processes, and more implicit, automatic processing, or by pointing toward findings in developmental neuroscience. Among the original research articles, a number focus on neural correlates of some form of live social interaction, either face-to-face, or via gaze and joint attention, joint action in various dual tasks such as imitation, behavioral or listener-speaker cou-pling. These are not limited to investigating only single agents' neural correlates, but also look at the coupling of participants' neural correlates within an interactive setup. The field of interest pertaining to the nature of interaction stretches far beyond that and incorporates inquiries into risk-taking, inequity, deception— often in the context of games, emotion, and face perception, machine interaction, the role of oxytocin, and specific interaction deficits in persons with autism.
Frontiers in Human Neuroscience 02/2013; · 2.34 Impact Factor
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ABSTRACT: Structural disconnectivity has been hypothesized as being accountable for the pathophysiology of schizophrenia. Morphometric variables suitable for the empirical study of disconnectivity were studied aiming at the research question whether empirical indicators for disconnectivity are already informative in subjects at risk (SAR) and in young matched patients diagnosed with schizophrenia (SZ). In MRI data of subjects of the two diagnostic groups SZ and SAR, the size of the corpus callosum (CC) as indicator for interhemispherical long distance connections and the gyrification index (GI) as indicator for cortico-cortical connections were analyzed compared to a healthy controls (HC). Each subgroup consists of 21 subjects matched for sex and age. Measurements of the CC and GI were estimated in manually performed tracing procedures. GI data revealed significant differences between the diagnostic groups of both SAR and SZ as compared to HC in the frontal and parietal cortices. Measurements of total CC yielded no significant differences between diagnostic groups. The results are suggestive for impaired cortico-cortical connections as indicated by gyrification changes in SZ and also in SAR, whereas interhemispherical connectivity at the same time appears to be unaffected.
Archiv f ur Psychiatrie und Nervenkrankheiten 07/2012; · 2.75 Impact Factor
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ABSTRACT: We investigated the influence of control over a social stimulus on the ability to detect direct gaze in high-functioning autism (HFA). In a pilot study, 19 participants with and 19 without HFA were compared on a gaze detection and a gaze setting task. Participants with HFA were less accurate in detecting direct gaze in the detection task, but did not differ in their ability to establish direct gaze in the setting task. In the main experiment, the results of the pilot study were replicated with 37 participants with and 39 without HFA, suggesting that individuals with HFA have a specific deficit in the passive perception of social cues as opposed to the active control, which seems to be intact.
Journal of Autism and Developmental Disorders 06/2012; · 3.34 Impact Factor
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ABSTRACT: Although theories that examine direct links between behavior and brain remain incomplete, it is known that brain expansion
significantly correlates with caloric and oxygen demands. Therefore, one of the principles governing evolutionary cognitive
neuroscience is that cognitive abilities that require significant brain function (and/or structural support) must be accompanied
by significant fitness benefit to offset the increased metabolic demands. One such capacity is self-awareness (SA), which
(1) is found only in the greater apes and (2) remains unclear in terms of both cortical underpinning and possible fitness
benefit. In the current experiment, transcranial magnetic stimulation (TMS) was applied to the prefrontal cortex during a
spatial perspective-taking task involving self and other viewpoints. It was found that delivery of TMS to the right prefrontal
region disrupted self-, but not other-, perspective. These data suggest that self-awareness may have evolved in concert with
other right hemisphere cognitive abilities.
Human Nature 04/2012; 18(2):132-142. · 1.96 Impact Factor
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ABSTRACT: First impressions profoundly influence our attitudes and behavior toward others. However, little is known about whether and to what degree the cognitive processes that underlie impression formation depend on the domain of the available information about the target person. To investigate the neural bases of the influence of verbal as compared to nonverbal information on interpersonal judgments, we identified brain regions where the BOLD signal parametrically increased with increasing strength of evaluation based on either short text vignettes or mimic and gestural behavior. While for verbal stimuli the increasing strength of subjective evaluation was correlated with increased neural activation of precuneus and posterior cingulate cortex (PC/PCC), a similar effect was observed for nonverbal stimuli in the amygdala. These findings support the assumption that qualitatively different cognitive operations underlie person evaluation depending upon the stimulus domain: while the processing of nonverbal person information may be more strongly associated with affective processing as indexed by recruitment of the amygdala, verbal person information engaged the PC/PCC that has been related to social inferential processing.
NeuroImage 03/2012; 60(1):179-88. · 5.89 Impact Factor
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ABSTRACT: Morally judicious behavior forms the fabric of human sociality. Here, we sought to investigate neural activity associated with different facets of moral thought. Previous research suggests that the cognitive and emotional sources of moral decisions might be closely related to theory of mind, an abstract-cognitive skill, and empathy, a rapid-emotional skill. That is, moral decisions are thought to crucially refer to other persons' representation of intentions and behavioral outcomes as well as (vicariously experienced) emotional states. We thus hypothesized that moral decisions might be implemented in brain areas engaged in 'theory of mind' and empathy. This assumption was tested by conducting a large-scale activation likelihood estimation (ALE) meta-analysis of neuroimaging studies, which assessed 2,607 peak coordinates from 247 experiments in 1,790 participants. The brain areas that were consistently involved in moral decisions showed more convergence with the ALE analysis targeting theory of mind versus empathy. More specifically, the neurotopographical overlap between morality and empathy disfavors a role of affective sharing during moral decisions. Ultimately, our results provide evidence that the neural network underlying moral decisions is probably domain-global and might be dissociable into cognitive and affective sub-systems.
Brain Structure and Function 01/2012; 217(4):783-96. · 5.63 Impact Factor
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ABSTRACT: Previous research suggests overlap between brain regions that show task-induced deactivations and those activated during the performance of social-cognitive tasks. Here, we present results of quantitative meta-analyses of neuroimaging studies, which confirm a statistical convergence in the neural correlates of social and resting state cognition. Based on the idea that both social and unconstrained cognition might be characterized by introspective processes, which are also thought to be highly relevant for emotional experiences, a third meta-analysis was performed investigating studies on emotional processing. By using conjunction analyses across all three sets of studies, we can demonstrate significant overlap of task-related signal change in dorso-medial prefrontal and medial parietal cortex, brain regions that have, indeed, recently been linked to introspective abilities. Our findings, therefore, provide evidence for the existence of a core neural network, which shows task-related signal change during socio-emotional tasks and during resting states.
PLoS ONE 01/2012; 7(2):e30920. · 4.09 Impact Factor
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ABSTRACT: Social gaze provides a window into the interests and intentions of others and allows us to actively point out our own. It enables us to engage in triadic interactions involving human actors and physical objects and to build an indispensable basis for coordinated action and collaborative efforts. The object-related aspect of gaze in combination with the fact that any motor act of looking encompasses both input and output of the minds involved makes this non-verbal cue system particularly interesting for research in embodied social cognition. Social gaze comprises several core components, such as gaze-following or gaze aversion. Gaze-following can result in situations of either "joint attention" or "shared attention." The former describes situations in which the gaze-follower is aware of sharing a joint visual focus with the gazer. The latter refers to a situation in which gazer and gaze-follower focus on the same object and both are aware of their reciprocal awareness of this joint focus. Here, a novel interactive eye-tracking paradigm suited for studying triadic interactions was used to explore two aspects of social gaze. Experiments 1a and 1b assessed how the latency of another person's gaze reactions (i.e., gaze-following or gaze version) affected participants' sense of agency, which was measured by their experience of relatedness of these reactions. Results demonstrate that both timing and congruency of a gaze reaction as well as the other's action options influence the sense of agency. Experiment 2 explored differences in gaze dynamics when participants were asked to establish either joint or shared attention. Findings indicate that establishing shared attention takes longer and requires a larger number of gaze shifts as compared to joint attention, which more closely seems to resemble simple visual detection. Taken together, novel insights into the sense of agency and the awareness of others in gaze-based interaction are provided.
Frontiers in psychology. 01/2012; 3:537.
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ABSTRACT: The field of social neuroscience has made considerable progress in unraveling the neural correlates of human cooperation by making use of brain imaging methods. Within this field, neuroeconomic research has drawn on paradigms from experimental economics, such as the Prisoner's Dilemma (PD) and the Trust Game. These paradigms capture the topic of conflict in cooperation, while focusing strongly on outcome-related decision processes. Cooperation, however, does not equate with that perspective, but relies on additional psychological processes and events, including shared intentions and mutually coordinated joint action. These additional facets of cooperation have been successfully addressed by research in developmental psychology, cognitive science, and social philosophy. Corresponding neuroimaging data, however, is still sparse. Therefore, in this paper, we present a juxtaposition of these mutually related but mostly independent trends in cooperation research. We propose that the neuroscientific study of cooperation could benefit from paradigms and concepts employed in developmental psychology and social philosophy. Bringing both to a neuroimaging environment might allow studying the neural correlates of cooperation by using formal models of decision-making as well as capturing the neural responses that underlie joint action scenarios, thus, promising to advance our understanding of the nature of human cooperation.
Frontiers in Human Neuroscience 01/2012; 6:148. · 2.34 Impact Factor
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ABSTRACT: Cortical thickness (CT) changes possibly contribute to the complex symptomatology of autism. The aberrant developmental trajectories underlying such differences in certain brain regions and their continuation in adulthood are a matter of intense debate. We studied 28 adults with high-functioning autism (HFA) and 28 control subjects matched for age, gender, IQ and handedness. A surface-based whole brain analysis utilizing FreeSurfer was employed to detect CT differences between the two diagnostic groups and to investigate the time course of age-related changes. Direct comparison with control subjects revealed thinner cortex in HFA in the posterior superior temporal sulcus (pSTS) of the left hemisphere. Considering the time course of CT development we found clusters around the pSTS and cuneus in the left and the paracentral lobule in the right hemisphere to be thinner in HFA with comparable age-related slopes in patients and controls. Conversely, we found clusters around the supramarginal gyrus and inferior parietal lobule (IPL) in the left and the precentral and postcentral gyrus in the right hemisphere to be thinner in HFA, but with different age-related slopes in patients and controls. In the latter regions CT showed a steady decrease in controls but no analogous thinning in HFA. CT analyses contribute in characterizing neuroanatomical correlates of HFA. Reduced CT is present in brain regions involved in social cognition. Furthermore, our results demonstrate that aberrant brain development leading to such differences is proceeding throughout adulthood. Discrepancies in prior morphometric studies may be induced by the complex time course of cortical changes.
NeuroImage 09/2011; 58(2):391-400. · 5.89 Impact Factor
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ABSTRACT: Previous evidence suggests that 'social gaze' can not only cause shifts in attention, but also can change the perception of objects located in the direction of gaze and how these objects will be manipulated by an observer. These findings implicate differences in the neural networks sub-serving action control driven by social cues as compared with nonsocial cues. Here, we sought to explore this hypothesis by using functional magnetic resonance imaging and a stimulus-response compatibility paradigm in which participants were asked to generate spatially congruent or incongruent motor responses to both social and nonsocial stimuli. Data analysis revealed recruitment of a dorsal frontoparietal network and the locus coeruleus for the generation of incongruent motor responses, areas previously implicated in controlling attention. As a correlate for the effect of 'social gaze' on action control, an interaction effect was observed for incongruent responses to social stimuli in sub-cortical structures, anterior cingulate and inferior frontal cortex. Our results, therefore, suggest that performing actions in a--albeit minimal--social context significantly changes the neural underpinnings of action control and recruits brain regions previously implicated in action monitoring, the reorienting of attention and social cognition.
Social Cognitive and Affective Neuroscience 09/2011; 6(4):393-403. · 6.13 Impact Factor
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ABSTRACT: Individuals suffering from autism spectrum disorders (ASD) often show a tendency for detail- or feature-based perception (also referred to as "local processing bias") instead of more holistic stimulus processing typical for unaffected people. This local processing bias has been demonstrated for the visual and auditory domains and there is evidence that multisensory processing may also be affected in ASD. Most multisensory processing paradigms used social-communicative stimuli, such as human speech or faces, probing the processing of simultaneously occuring sensory signals. Multisensory processing, however, is not limited to simultaneous stimulation. In this study, we investigated whether multisensory processing deficits in ASD persist when semantically complex but nonsocial stimuli are presented in succession. Fifteen adult individuals with Asperger syndrome and 15 control persons participated in a visual-audio priming task, which required the classification of sounds that were either primed by semantically congruent or incongruent preceding pictures of objects. As expected, performance on congruent trials was faster and more accurate compared with incongruent trials (crossmodal priming effect). The Asperger group, however, did not differ significantly from the control group. Our results do not support a general multisensory processing deficit, which is universal to the entire autism spectrum.
Autism Research 08/2011; 4(5):383-8. · 3.69 Impact Factor
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ABSTRACT: Perceiving someone else's gaze shift toward an object can influence how this object will be manipulated by the observer, suggesting a modulatory effect of a gaze-based social context on action control. High-functioning autism (HFA) is characterized by impairments of social interaction, which may be associated with an inability to automatically integrate socially relevant nonverbal cues when generating actions. To explore these hypotheses, we made use of a stimulus-response compatibility paradigm in which a comparison group and patients with HFA were asked to generate spatially congruent or incongruent motor responses to changes in a face, a face-like and an object stimulus. Results demonstrate that while in the comparison group being looked at by a virtual other leads to a reduction of reaction time costs associated with generating a spatially incongruent response, this effect is not present in the HFA group. We suggest that this modulatory effect of social gaze on action control might play an important role in direct social interactions by helping to coordinate one's actions with those of someone else. Future research should focus on these implicit mechanisms of interpersonal alignment ('online' social cognition), which might be at the very heart of the difficulties individuals with autism experience in everyday social encounters.
Autism 08/2011; 16(2):151-62. · 2.27 Impact Factor
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ABSTRACT: In social interaction, gaze behavior provides important signals that have a significant impact on our perception of others. Previous investigations, however, have relied on paradigms in which participants are passive observers of other persons' gazes and do not adjust their gaze behavior as is the case in real-life social encounters. We used an interactive eye-tracking paradigm that allows participants to interact with an anthropomorphic virtual character whose gaze behavior is responsive to where the participant looks on the stimulus screen in real time. The character's gaze reactions were systematically varied along a continuum from a maximal probability of gaze aversion to a maximal probability of gaze-following during brief interactions, thereby varying contingency and congruency of the reactions. We investigated how these variations influenced whether participants believed that the character was controlled by another person (i.e., a confederate) or a computer program. In a series of experiments, the human confederate was either introduced as naïve to the task, cooperative, or competitive. Results demonstrate that the ascription of humanness increases with higher congruency of gaze reactions when participants are interacting with a naïve partner. In contrast, humanness ascription is driven by the degree of contingency irrespective of congruency when the confederate was introduced as cooperative. Conversely, during interaction with a competitive confederate, judgments were neither based on congruency nor on contingency. These results offer important insights into what renders the experience of an interaction truly social: Humans appear to have a default expectation of reciprocation that can be influenced drastically by the presumed disposition of the interactor to either cooperate or compete.
PLoS ONE 01/2011; 6(11):e27591. · 4.09 Impact Factor
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ABSTRACT: Die Fähigkeit, mit anderen Personen in einen interaktiven Austausch zu treten, gehört zu den wesentlichen kognitiven Ausstattungsmerkmalen
des Menschen und kann spekulativ sogar als Ausgangspunkt unserer kulturellen Entwicklung angenommen werden. Eine wesentliche
Komponente dieser Leistungen, die verbal oder nonverbal vermittelt sein können, ist die Fähigkeit, anderen Personen „innere“
Zustände oder Erlebnisse zuzuschreiben. Diese Leistungen sind in den letzten Jahren auch zentraler Forschungsgegenstand der
kognitiven Neurowissenschaft geworden. Unter der Annahme der Naturalisierbarkeit dieser Leistungen hat sich hier das Forschungsprogramm
der sozialen Neurowissenschaft etabliert. Funktionell hirnbildgebende Verfahren zeigen, dass besonders der medial präfrontale
und der superior temporale bzw. temporoparietale Cortex wesentlich mit diesen sozial kognitiven Leistungen assoziiert sind.
Damit steht eine Methodologie zur Verfügung, die es nun auch erlaubt, die Diversität sozialer Informationsverarbeitung in
den Blick zu nehmen, die sich beispielsweise aus psychopathologisch relevanten Grenzzuständen oder kultureller Variabilität
ergeben kann.
12/2010: pages 111-137;
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Consciousness and Cognition 09/2010; 19(3):687-9. · 2.31 Impact Factor
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ABSTRACT: The goal of the study was to investigate the size of the corpus callosum (CC) and its subsegments in relation to total brain volume (TBV) as an empirical indicator of impaired connectivity in autism with special respect to gender. In MRI data sets of 29 adults with high-functioning autism (HFA) and 29 age-, gender- and IQ-matched control subjects, the TBV was measured and the CC was analyzed as a whole and in subsegments employing two different manual segmentation procedures. With respect to diagnosis, there were no significant differences in the dependent variables (CC, CC subsegments, and TBV). With respect to gender, only TBV was significantly increased in males compared with females, resulting in a significantly decreased CC/TBV ratio in males. This finding, however, was independent from gender and can be fully attributed to brain size. Our findings do not support the following hypotheses: (1) a hypothesis of impaired CC in HFA adults as a subgroup of patients with autism spectrum disorders, and (2) the sexual dimorphism hypothesis of the CC.
Psychiatry Research 07/2010; 183(1):38-43. · 2.52 Impact Factor
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ABSTRACT: Individuals with autism often show a fragmented way of perceiving their environment, suggesting a disorder of information integration, possibly due to disrupted communication between brain areas. We investigated thirteen individuals with high-functioning autism (HFA) and thirteen healthy controls using the metastable motion quartet, a stimulus consisting of two dots alternately presented at four locations of a hypothetical square, thereby inducing an apparent motion percept. This percept is vertical or horizontal, the latter requiring binding of motion signals across cerebral hemispheres. Decreasing the horizontal distance between dots could facilitate horizontal percepts. We found evidence for altered horizontal binding in HFA: Individuals with HFA needed stronger facilitation to experience horizontal motion. These data are interpreted in light of reduced cross-hemispheric communication.
Journal of Autism and Childhood Schizophrenia 04/2010; 40(12):1549-51. · 3.06 Impact Factor
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ABSTRACT: The field of social neuroscience has made remarkable progress in elucidating the neural mechanisms of social cognition. More recently, the need for new experimental approaches has been highlighted that allow studying social encounters in a truly interactive manner by establishing 'online' reciprocity in social interaction. In this article, we present a newly developed adaptation of a method which uses eyetracking data obtained from participants in real time to control visual stimulation during functional magnetic resonance imaging, thus, providing an innovative tool to generate gaze-contingent stimuli in spite of the constraints of this experimental setting. We review results of two paradigms employing this technique and demonstrate how gaze data can be used to animate a virtual character whose behavior becomes 'responsive' to being looked at allowing the participant to engage in 'online' interaction with this virtual other in real-time. Possible applications of this setup are discussed highlighting the potential of this development as a new 'tool of the trade' in social cognitive and affective neuroscience.
Social Cognitive and Affective Neuroscience 03/2010; 5(1):98-107. · 6.13 Impact Factor
