TY - JOUR A1 - Kliegl, Reinhold T1 - Publication statistics show collaboration, not competition Y1 - 2008 ER - TY - JOUR A1 - Moshel, Shay A1 - Zivotofsky, Ari Z. A1 - Liang, Jin-Rong A1 - Engbert, Ralf A1 - Kurths, Jürgen A1 - Kliegl, Reinhold A1 - Havlin, Shlomo T1 - Persistence and phase synchronization properties of fixational eye movement N2 - When we fixate our gaze on a stable object, our eyes move continuously with extremely small involuntary and autonomic movements, that even we are unaware of during their occurrence. One of the roles of these fixational eye movements is to prevent the adaptation of the visual system to continuous illumination and inhibit fading of the image. These random, small movements are restricted at long time scales so as to keep the target at the centre of the field of view. In addition, the synchronisation properties between both eyes are related to binocular coordination in order to provide stereopsis. We investigated the roles of different time scale behaviours, especially how they are expressed in the different spatial directions (vertical versus horizontal). We also tested the synchronisation between both eyes. Results show different scaling behaviour between horizontal and vertical movements. When the small ballistic movements, i.e., microsaccades, are removed, the scaling behaviour in both axes becomes similar. Our findings suggest that microsaccades enhance the persistence at short time scales mostly in the horizontal component and much less in the vertical component. We also applied the phase synchronisation decay method to study the synchronisation between six combinations of binocular fixational eye movement components. We found that the vertical-vertical components of right and left eyes are significantly more synchronised than the horizontal-horizontal components. These differences may be due to the need for continuously moving the eyes in the horizontal plane in order to match the stereoscopic image for different viewing distances. Y1 - 2008 UR - 1960 = DOI: 10.1140/epjst/e2008-00762-3 SN - 1951-6355 ER - TY - JOUR A1 - Laucht, Manfred A1 - Becker, Katja A1 - Frank, Josef A1 - Schmidt, Martin H. A1 - Esser, Günter A1 - Treutlein, Jens A1 - Skowronek, Markus H. A1 - Schumann, Gunter T1 - Genetic variation in dopamine pathways differentially associated with smoking progression in adolescence N2 - Objective: To clarify the nature of the association between dopamine genes and smoking by examining whether genetic variability in components of the dopamine pathway could explain refined phenotypes in adolescent smoking progression. Method: Data are from an ongoing prospective study of the long-term outcome of early risk factors studied since birth. At age 15 years, 220 participants (108 males, 112 females) completed a self-report questionnaire measuring smoking behavior and were genotyped for five dopamine gene variants. Results: Smoking initiation was related to allelic variation in the dopamine D-4 receptor gene (DRD4), whereas smoking continuation and dependence showed association with the dopamine D-2 receptor gene (DRD2). Adolescents with the seven-repeat allele of the common DRD4 exon 3 polymorphism had rates of ever smoking that were significantly higher than in those with other genotypes. Once smoking started, carriers of the T allele of a single nucleotide polymorphism of DRD2 (rs4648317) reported higher rates of current smoking and scored higher on nicotine dependence than their allelic counterparts. Among current smokers, intention to quit was significantly lower in adolescents homozygous for the 10-repeat allele of the common dopamine transporter 3 untranslated region polymorphism. Conclusions: Our results provide preliminary evidence of genetic influences on different stages of smoking and suggest the importance of specific dopamine genes in smoking progression in adolescence. Y1 - 2008 U6 - https://doi.org/10.1097/Chi.0b013e31816bff77 SN - 0890-8567 ER - TY - JOUR A1 - Laubrock, Jochen A1 - Engbert, Ralf A1 - Kliegl, Reinhold T1 - Fixational eye movements predict the perceived direction of ambiguous apparent motion N2 - Neuronal activity in area LIP is correlated with the perceived direction of ambiguous apparent motion (Z. M. Williams, J. C. Elfar, E. N. Eskandar, L. J. Toth, & J. A. Assad, 2003). Here we show that a similar correlation exists for small eye movements made during fixation. A moving dot grid with superimposed fixation point was presented through an aperture. In a motion discrimination task, unambiguous motion was compared with ambiguous motion obtained by shifting the grid by half of the dot distance. In three experiments we show that (a) microsaccadic inhibition, i.e., a drop in microsaccade frequency precedes reports of perceptual flips, (b) microsaccadic inhibition does not accompany simple response changes, and (c) the direction of microsaccades occurring before motion onset biases the subsequent perception of ambiguous motion. We conclude that microsaccades provide a signal on which perceptual judgments rely in the absence of objective disambiguating stimulus information. Y1 - 2008 UR - http://www.journalofvision.org/content/by/year U6 - https://doi.org/10.1167/8.14.13 SN - 1534-7362 ER - TY - JOUR A1 - Kinder, Annette A1 - Rolfs, Martin A1 - Kliegl, Reinhold T1 - Sequence learning at optimal stimulus-response mapping : evidence from a serial reaction-time task N2 - We propose a new version of the serial reaction time (SRT) task in which participants merely looked at the target instead of responding manually. As response locations were identical to target locations, stimulus - response compatibility was maximal in this task. We demonstrated that saccadic response times decreased during training and increased again when a new sequence was presented. It is unlikely that this effect was caused by stimulus - response (S - R) learning because bonds between (visual) stimuli and (oculomotor) responses were already well established before the experiment started. Thus, the finding shows that the building of S - R bonds is not essential for learning in the SRT task. Y1 - 2008 UR - http://tandfprod.literatumonline.com/doi/full/10.1080/17470210701557555 U6 - https://doi.org/10.1080/17470210701557555 ER - TY - JOUR A1 - Titze, Karl A1 - Koch, Sabine A1 - Helge, Hans A1 - Lehmkuhl, Ulrike A1 - Rauh, Hellgard A1 - Steinhausen, Hans-Christoph T1 - Prenatal and familial risks of children born by epileptic mothers : long term effects on the cognitive development Y1 - 2008 UR - http://onlinelibrary.wiley.com/doi/10.1111/j.1469-8749.2007.02020.x/pdf U6 - https://doi.org/10.1111/j.1469-8749.2007.02020.x ER - TY - JOUR A1 - Becker, Katja A1 - El-Faddagh, Mahha A1 - Schmidt, Martin H. A1 - Esser, Günter A1 - Laucht, Manfred T1 - Interaction of dopamine transporter genotype with prenatal smoke exposure on ADHD symptoms N2 - Objective To demonstrate that children homozygous for the 10-repeat allele of the common dopamine transporter (DAT1) polymorphism who were exposed to maternal prenatal smoke exhibited significantly higher hyperactivity-impulsivity than children without these environmental or genetic risks. Study design We performed a prospective longitudinal study from birth into early adulthood monitoring the long-term outcome of early risk factors. Maternal prenatal smoking was determined during a standardized interview with the mother when the child was 3 months old. At age 15 years, 305 adolescents participated in genotyping for the DAT1 40 base pair variable number of tandem repeats polymorphism and assessment of inattention, hyperactivity-impulsivity, and oppositional defiant/conduct disorder symptoms with die Kiddie- Sads-Present and Lifetime Version. Results There was no bivariate association between DAT1 genotype, prenatal smoke exposure and symptoms of attention deficit hyperactivity disorder. However, a significant interaction between DAT1 genotype and prenatal smoke exposure emerged (P =.012), indicating that males with prenatal smoke exposure who were homozygous for the DAT1 10r allele had higher hyperactivity-impulsivity than males from all other groups. In females, no significant main effects of DAT1 genotype or prenatal smoke exposure or interaction effects on any symptoms were evident (all P >.25). Conclusions This study provides further evidence for the multifactorial nature of attention deficit hyperactivity disorder and the importance of studying both genetic and environmental factors and their interaction. Y1 - 2008 SN - 0022-3476 ER - TY - JOUR A1 - Ihle, Wolfgang A1 - Laucht, Manfred T1 - Unter welchen Bedingungen macht Armut psychisch krank? Y1 - 2008 SN - 978-3-940793-34-8 ER - TY - JOUR A1 - Bohn, Christiane A1 - Kliegl, Reinhold T1 - Mikrobewegungen des Auges und Nanophilologie : was uns die Blickbewegungen über die Verarbeitungsprozesse beim Lesen verraten Y1 - 2008 SN - 978-3-484-55047-6 ER - TY - JOUR A1 - Esser, Günter T1 - Verhaltensdiagnostik N2 - Unter Verhaltensdiagnostik versteht man ein Buendel diagnostischer Instrumente, die darauf abzielen, die aenderungsmoeglichkeiten von Problemverhalten zu eruieren. Verhaltensdiagnostik ist das klassische diagnostische Vorgehen der Verhaltenstherapie. Ausgehend von einer Analyse des Problemverhaltens und der Bedingungen seines Auftretens werden durch verschiedene Techniken Hinweise zu seiner Genese und seiner Aufrechterhaltung erwartet. Vertreter der Verhaltensdiagnostik sehen sie als Alternative und im Gegensatz zur klassischen Eigenschaftsdiagnostik (Reinecker-Hecht & Baumann, 1998), zu der die Ergebnisse aus psychologischen Testverfahren zur Erfassung von Intelligenzleistungen und Persoenlichkeitsmerkmalen ebenso zaehlen wie die Diagnostischen Klassifikationssysteme (z.B. ICD-10 oder DSM- IV)à. Y1 - 2008 SN - 978-3-13-126083-3 ER -