@phdthesis{Herrmann2003, author = {Herrmann, Martin Josef}, title = {Neurophysiologische Korrelate der Verarbeitung von Gesichtern und emotionalen Gesichtsausdr{\"u}cken bei Gesunden und Patienten mit schizophrenen Erkrankungen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-8202}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2003}, abstract = {Ausgangspunkt f{\"u}r diese Arbeit war die Diskrepanz zwischen der vielfach belegten Schwierigkeit schizophrener Patienten bei der Dekodierung emotionaler Gesichtsausdr{\"u}cke und dem mangelhaften Wissen {\"u}ber die hierf{\"u}r verantwortlichen Prozesse. In der Literatur der letzten Jahre gab es einige viel versprechende Ergebnisse, die nahe legten, dass mit dem Elektroenzephalogramm (EEG) sowohl die Verarbeitung von Gesichtern, als auch der Mimik messbar ist. Somit w{\"a}re das EEG eine geeignete Methode den Prozess der Emotionsdekodierung bei schizophrenen Patienten zu untersuchen. Diese Arbeit untersucht folgende zwei Hauptfragestellungen. Erstens, wie lassen sich die f{\"u}r die Verarbeitung von Gesichtern und das Erkennen von emotionalen Gesichtsausdr{\"u}cken verantwortlichen kognitiven Prozesse mit Hilfe ereigniskorrelierter Potentiale des EEGs reliabel messen? Zweitens, sind diese Prozesse bei schizophrenen Patienten im Vergleich zu gesunden Probanden beeintr{\"a}chtigt? Zur Kl{\"a}rung der ersten Fragestellung wurden drei Stichproben gesunder Personen untersucht. Es zeigte sich in allen drei Untersuchungen, dass sich die Verarbeitung von Gesichtern im Vergleich zu Kontrollreizen in einer negativen Komponente um 170 ms {\"u}ber temporalen Elektrodenpositionen widerspiegelt (Gesichterpeak, N170). Die N170 konnte mit dem Quellenlokalisationsprogramm LORETA unter anderem im Gyrus Fusiformis, der entsprechenden Hirnregion f{\"u}r die Gesichtsverarbeitung, lokalisiert werden. F{\"u}r die Dekodierung emotionaler Gesichtsausdr{\"u}cke konnten keine wiederholbaren Effekte nachgewiesen werden. Im Weiteren wurde die Gesichtsverarbeitung bei schizophrenen Patienten untersucht. 22 als schizophren diagnostizierte Patienten wurden mit einer nach dem Alter, dem Geschlecht und dem Bildungsstatus angepassten Kontrollgruppe verglichen. In dieser Auswertung deutete sich bei schizophrenen Patienten ein Defizit in den fr{\"u}hen Verarbeitungsschritten von Gesichtern an. Dieses Ergebnis wurde in dieser Art noch nicht gezeigt und reiht sich ein in Studien, die sowohl strukturelle Ver{\"a}nderungen in den f{\"u}r die Gesichtsverarbeitung wesentlichen Hirnregionen bei schizophrenen Patienten zeigen konnten als auch ein allgemeines Defizit fr{\"u}her visueller Verarbeitung nahe legen.}, subject = {Schizophrener}, language = {de} } @article{KleihKuebler2013, author = {Kleih, Sonja C. and K{\"u}bler, Andrea}, title = {Empathy, motivation, and P300-BCI performance}, series = {Frontiers in Human Neuroscience}, volume = {7}, journal = {Frontiers in Human Neuroscience}, number = {642}, doi = {10.3389/fnhum.2013.00642}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-130559}, year = {2013}, abstract = {Motivation moderately influences brain-computer interface (BCI) performance in healthy subjects when monetary reward is used to manipulate extrinsic motivation. However, the motivation of severely paralyzed patients, who are potentially in need for BCI, could mainly be internal and thus, an intrinsic motivator may be more powerful. Also healthy subjects who participate in BCI studies could be internally motivated as they may wish to contribute to research and thus extrinsic motivation by monetary reward would be less important than the content of the study. In this respect, motivation could be defined as "motivation-to-help." The aim of this study was to investigate, whether subjects with high motivation for helping and who are highly empathic would perform better with a BCI controlled by event-related potentials (P300-BCI). We included N = 20 healthy young participants na{\"i}ve to BCI and grouped them according to their motivation for participating in a BCI study in a low and highly motivated group. Motivation was further manipulated with interesting or boring presentations about BCI and the possibility to help patients. Motivation for helping did neither influence BCI performance nor the P300 amplitude. Post hoc, subjects were re-grouped according to their ability for perspective taking. We found significantly higher P300 amplitudes on parietal electrodes in participants with a low ability for perspective taking and therefore, lower empathy, as compared to participants with higher empathy. The lack of an effect of motivation on BCI performance contradicts previous findings and thus, requires further investigation. We speculate that subjects with higher empathy who are good perspective takers with regards to patients in potential need of BCI, may be more emotionally involved and therefore, less able to allocate attention on the BCI task at hand.}, language = {en} } @article{ErlbeckKueblerKotchoubeyetal.2014, author = {Erlbeck, Helena and K{\"u}bler, Andrea and Kotchoubey, Boris and Veser, Sandra}, title = {Task instructions modulate the attentional mode affecting the auditory MMN and the semantic N400}, series = {Frontiers in Human Neuroscience}, volume = {8}, journal = {Frontiers in Human Neuroscience}, number = {654}, doi = {10.3389/fnhum.2014.00654}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-115553}, year = {2014}, abstract = {Event-related potentials (ERPs) have been proven to be a useful tool to complement clinical assessment and to detect residual cognitive functions in patients with disorders of consciousness. These ERPs are of ten recorded using passive or unspecific instructions. Patient data obtained this way are then compared to data from healthy participants, which are usually recorded using active instructions. The present study investigates the effect of attentive modulations and particularly the effect of activevs. passive instruction on the ERP components mismatch negativity (MMN) and N400. A sample of 18 healthy participants listened to three auditory paradigms: anoddball, aword priming, and a sentence paradigm. Each paradigm was presented three times with different instructions: ignoring auditory stimuli, passive listening, and focused attention on the auditory stimuli. After each task, the participants indicated their subjective effort. The N400 decreased from the focused task to the passive task, and was extinct in the ignore task. The MMN exhibited higher amplitudes in the focused and passive task compared to the ignore task. The data indicate an effect of attention on the supratemporal component of the MMN. Subjective effort was equally high in the passive and focused tasks but reduced in the ignore task. We conclude that passive listening during EEG recording is stressful and attenuates ERPs, which renders the interpretation of the results obtained in such conditions difficult.}, language = {en} } @article{BlechertMeuleBuschetal.2014, author = {Blechert, Jens and Meule, Adrian and Busch, Niko A. and Ohla, Kathrin}, title = {Food-pics: an image database for experimental research on eating and appetite}, series = {Frontiers in Psychology}, volume = {5}, journal = {Frontiers in Psychology}, issn = {1664-1078}, doi = {10.3389/fpsyg.2014.00617}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-115987}, pages = {617}, year = {2014}, abstract = {Our current environment is characterized by the omnipresence of food cues. The sight and smell of real foods, but also graphically depictions of appetizing foods, can guide our eating behavior, for example, by eliciting food craving and influencing food choice. The relevance of visual food cues on human information processing has been demonstrated by a growing body of studies employing food images across the disciplines of psychology, medicine, and neuroscience. However, currently used food image sets vary considerably across laboratories and image characteristics (contrast, brightness, etc.) and food composition (calories, macronutrients, etc.) are often unspecified. These factors might have contributed to some of the inconsistencies of this research. To remedy this, we developed food-pics, a picture database comprising 568 food images and 315 non-food images along with detailed meta-data. A total of N = 1988 individuals with large variance in age and weight from German speaking countries and North America provided normative ratings of valence, arousal, palatability, desire to eat, recognizability and visual complexity. Furthermore, data on macronutrients (g), energy density (kcal), and physical image characteristics (color composition, contrast, brightness, size, complexity) are provided. The food-pics image database is freely available under the creative commons license with the hope that the set will facilitate standardization and comparability across studies and advance experimental research on the determinants of eating behavior. Read F}, language = {en} } @article{RealKotchoubeyKuebler2014, author = {Real, Ruben G. L. and Kotchoubey, Boris and K{\"u}bler, Andrea}, title = {Studentized continuous wavelet transform (t-CWT) in the analysis of individual ERPs: real and simulated EEG data}, doi = {10.3389/fnins.2014.00279}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-113581}, year = {2014}, abstract = {This study aimed at evaluating the performance of the Studentized Continuous Wavelet Transform (t-CWT) as a method for the extraction and assessment of event-related brain potentials (ERP) in data from a single subject. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of the t-CWT were assessed and compared to a variety of competing procedures using simulated EEG data at six low signal-to-noise ratios. Results show that the t-CWT combines high sensitivity and specificity with favorable PPV and NPV. Applying the t-CWT to authentic EEG data obtained from 14 healthy participants confirmed its high sensitivity. The t-CWT may thus be well suited for the assessment of weak ERPs in single-subject settings.}, language = {en} }