Sabine Windmann

Electrophysiological Correlates of Emotion-Induced Recognition Bias

The question of how emotions influence recognition memory is of interest not only within basic cognitive neuro-science but from clinical and forensic perspectives as well. Emotional stimuli can induce at recognition bias such that individuals are more likely to respond old to a negative item than to an emotionally neutral item, whether the item is actually old or new. We investigated this bias using event-related brain potential (ERP) measures by comparing the processing of words given old responses with accurate recognition of old/new differences. For correctly recognized items, the ERP difference between old items (hits) and new items (correct rejections, CR) was largely unaffected by emotional violence. That is, regardless of emotional valence, the ERP associated with hits was characterized by a widespread positivity between 300 and 700 msec relative to that for CRs. By contrast, the analysis of ERPs to old and new items that were judged old (hits and false alarms [FAs], respectively) revealed a differential effect of valence by 300 msec: Neutral items showed a large old/new difference over prefrontal sites, whereas negative items did not. These results are the first clear demonstration of response bias effects on ERPs linked to recognition memory. They are consistent with the idea that frontal cortex areas may be responsible for relaxing the retrieval criterion for negative stimuli so as to ensure that emotional events are not as easily missed or forgotten as neutral events.

Beyond revenge: Neural and genetic bases of altruistic punishment

It is still debated how altruistic punishment as one form of strong reciprocity has established during evolution and which motives may underlie such behavior. Recent neuroscientific evidence on the activation of brain reward regions during altruistic punishment in two-person one-shot exchange games suggests satisfaction through the punishment of norm violations as one underlying motive. In order to address this issue in more detail, we used fMRI during a one-shot economic exchange game that warrants strong reciprocity by introducing a third party punishment condition wherein revenge is unlikely to play a role. We report here that indeed, reward regions such as the nucleus accumbens showed punishment-related activation. Moreover, we provide preliminary evidence that genetic variation of dopamine turnover impacts similarly on punishment-related nucleus accumbens activation during both first person and third party punishment. The overall pattern of results suggests a common cognitive-affective-motivational network as the driving force for altruistic punishment, with only quantitative differences between first person and third party perspectives.

Creativity and the brain: Uncovering the neural signature of conceptual expansion

Neurophysiological studies of creativity thus far have not allowed for clear conclusions to be made regarding the specific neural underpinnings of such complex cognition due to overgeneralizations concerning the creativity construct, heterogeneity in the type of creativity tasks used, and the questionable efficacy of the employed comparison tasks. A novel experimental design was developed in the present fMRI study which rendered it possible to investigate a critical facet of creative cognition - that of conceptual expansion - as distinct from general divergent thinking, working memory, or cognitive load. Brain regions involved in the retention, retrieval and integration of conceptual knowledge such as the anterior inferior frontal gyrus, the temporal poles and the lateral frontopolar cortex were found to be selectively involved during conceptual expansion. The findings go against generic ideas that argue for the dominance of the right hemisphere during creative thinking and indicate the necessity to reconsider the functions of regions such as the anterior cingulate cortex to include more abstract facets of cognitive control. This study represents a new direction in the investigation of creativity in that it highlights the necessity to adopt a process based perspective in which the multifaceted nature of creativity can be truly grasped.

On Framing Effects in Decision Making: Linking Lateral versus Medial Orbitofrontal Cortex Activation to Choice Outcome Processing

Two correlates of outcome processing in the orbitofrontal cortex (OFC) have been proposed in the literature: One hypothesis suggests that the lateral/medial division relates to representation of outcome valence (negative vs. positive), and the other suggests that the medial OFC maintains steady stimulus-outcome associations, whereas the lateral OFC represents changing (unsteady) outcomes to prepare for response shifts. These two hypotheses were contrasted by comparing the original with the inverted version of the Iowa Gambling Task in an event-related functional magnetic resonance imaging experiment. Results showed (1) that (caudo) lateral OFC was indeed sensitive to the steadiness of the outcomes and not merely to outcome valence and (2) that the original and the inverted tasks, although both designed to measure sensitivity for future outcomes, were not equivalent as they enacted different behaviors and brain activation patterns. Results are interpreted in terms of Kahneman and Tverskys prospect theory suggesting that cognitions and decisions are biased differentially when probabilistic future rewards are weighed against consistent punishments relative to the opposite scenario [Kahneman, D., & Tversky, A. Choices, values, and frames. American Psychologist, 39, 341350, 1984]. Specialized processing of unsteady rewards (involving caudolateral OFC) may have developed during evolution in support of goal-related thinking, prospective planning, and problem solving.

Role of the Prefrontal Cortex in Attentional Control over Bistable Vision

The primary source of top-down attentional control in object perception is the prefrontal cortex. This region is involved in the maintenance of goal-related information as well as in attentional selection and set shifting. Recent approaches have emphasized the role of top-down processes during elementary visual processes as exemplified in bistable vision where perception oscillates automatically between two mutually exclusive states. The prefrontal cortex might influence this process either by maintaining the dominant pattern while protecting it against the competing representation, or by facilitating perceptual switches between the two competing representations. To address this issue, we investigated reported perceptual reversals in patients with circumscribed lesions of the prefrontal cortex and healthy control participants in three experimental conditions: hold (maintaining the dominant view), speed (inducing as many perceptual switches as possible), and neutral (no intervention). Results indicated that although the patients showed normal switching rates in the neutral condition and were able to control perceptual switches in the hold condition as much as control subjects were, they were less able to facilitate reversals specifically in the speed condition. These results suggest that the prefrontal cortex is necessary to bias the selection of visual representations in accord with current goals, but is less essential for maintaining selected information active that is continuously available in the environment. As for attentional selection, the present results suggest that the prefrontal cortex initiates perceptual reversals by withdrawing top-down support from the dominant representation without (or prior to) boosting the suppressed view.

Creative Thinking in Adolescents with Attention Deficit Hyperactivity Disorder (ADHD)

A widened attentional focus, that is typically associated with ADHD, has been postulated to be accompanied by enhanced creative ability. However, creativity has been only limitedly examined in ADHD. Performance across several creativity measures were investigated in three groups: adolescents with ADHD, those with conduct disorder, and a healthy control sample. The ADHD group exhibited selective cognitive advantages and disadvantages by demonstrating an enhanced ability in overcoming the constraining influence of examples, but a reduced capacity to generate a functional invention during an imagery task. These findings are interpreted with reference to inhibitory control mechanisms and the contextual modulation of creative cognition. The authors thank Till Schneider and Meike Ramon for their assistance in carrying out the experiments. This study was financially supported by the International Graduate School of Neuroscience (IGSN) at the Ruhr University Bochum in Germany.

Conceptual expansion and creative imagery as a function of psychoticism

The ability to be creative is often considered a unique characteristic of conscious beings and many efforts have been directed at demonstrating a relationship between creativity and the personality construct of psychoticism. The present study sought to investigate this link explicitly by focusing on discrete facets of creative cognition, namely the originality/novelty dimension and the practicality/usefulness dimension. Based on Eysencks conceptualisation of psychoticism as being characterised by an overinclusive cognitive style, it was expected that higher levels of psychoticism would accompany a greater degree of conceptual expansion and elevated levels of originality in creative imagery, but would be unrelated to the practicality/usefulness of an idea. These hypotheses were confirmed in 80 healthy participants who were contrasted based on their EPQ psychoticism scale scores. Our findings suggest that the link between psychoticism and creativity is based on associative thinking and broader but weak top-down activation patterns rather than on goal-related thinking.

Creative thinking in schizophrenia: The role of executive dysfunction and symptom severity

Introduction. This study examines the notion of enhanced creative thinking in schizophrenia and determines the mediating role of executive dysfunction and symptom severity in this relationship. Method. Patients with chronic schizophrenia (n=28) were assessed on varied facets of creative cognition and standard tests of executive control relative to matched healthy control participants (n=18). Results. Multivariate analyses revealed poorer performance by the patient group across almost all creative and executive function measures, except in the ability to be unconstrained by the influence of restrictive examples. Symptom-based contrasts using partial correlations revealed that differences were most extensive in the presence of thought disorder. Using hierarchical regression analyses, performance on the executive function tasks was found to play a mediatory role on specific aspects of creative cognition. Conclusions. Results are at odds with the popular notion of enhanced creative thinking in schizophrenia, but elucidate complex interactions between executive control and certain facets of creative thinking. In particular, performance of the schizophrenia group on measures that tap creativity elements of fluency and relevance were either partially or fully mediated by their performance on the executive control tasks, but this was not true of measures of originality.

Selective Information Processing Advantages in Creative Cognition as a Function of Schizotypy

Schizotypy has been consistently associated with an enhanced capacity for creative thinking, but the specificity of this cognitive advantage is, as yet, unclear. Different facets of creative cognition were assessed in the present study by contrasting groups based on the degree of extreme schizotypy personality scores. The high schizotypy group exhibited a selective advantage with better performance relative to a low schizotypy group in overcoming the constraining influence of examples when trying to generate original responses. The results are contrasted with previous findings on a related construct of psychoticism and are interpreted with reference to inhibitory control and other executive functions.

Using a shoe as a plant pot: Neural correlates of passive conceptual expansion

Conceptual expansion is a key process that underlies our ability to think creatively. In the present event-related fMRI study, a modified Alternate Uses Task was used to identify brain regions involved during passive conceptual expansion and thereby separately assess the effects of the two defining elements of creative output: Originality (unusualness) and Relevance (appropriateness). Participants viewed word pairs consisting of an object and a use and indicated whether the given use was unusual and/or appropriate for the given object. Trials with object-use combinations judged as unusual and appropriate (HUHA) were contrasted against trials judged as just unusual but inappropriate (HULA) or just appropriate but not unusual (LUHA). As hypothesized, conceptual expansion related activation (HUHA) was found in the bilateral inferior frontal gyrus (BA 45, 47), left temporal pole (BA 38) and left frontopolar cortex (BA 10). We discuss the specific contributions of these regions with reference to semantic cognition.