TY - JOUR A1 - Ziegler, Georg C. A1 - Ehlis, Ann-Christine A1 - Weber, Heike A1 - Vitale, Maria Rosaria A1 - Zöller, Johanna E. M. A1 - Ku, Hsing-Ping A1 - Schiele, Miriam A. A1 - Kürbitz, Laura I. A1 - Romanos, Marcel A1 - Pauli, Paul A1 - Kalisch, Raffael A1 - Zwanzger, Peter A1 - Domschke, Katharina A1 - Fallgatter, Andreas J. A1 - Reif, Andreas A1 - Lesch, Klaus-Peter T1 - A Common CDH13 Variant is Associated with Low Agreeableness and Neural Responses to Working Memory Tasks in ADHD JF - Genes N2 - The cell—cell signaling gene CDH13 is associated with a wide spectrum of neuropsychiatric disorders, including attention-deficit/hyperactivity disorder (ADHD), autism, and major depression. CDH13 regulates axonal outgrowth and synapse formation, substantiating its relevance for neurodevelopmental processes. Several studies support the influence of CDH13 on personality traits, behavior, and executive functions. However, evidence for functional effects of common gene variation in the CDH13 gene in humans is sparse. Therefore, we tested for association of a functional intronic CDH13 SNP rs2199430 with ADHD in a sample of 998 adult patients and 884 healthy controls. The Big Five personality traits were assessed by the NEO-PI-R questionnaire. Assuming that altered neural correlates of working memory and cognitive response inhibition show genotype-dependent alterations, task performance and electroencephalographic event-related potentials were measured by n-back and continuous performance (Go/NoGo) tasks. The rs2199430 genotype was not associated with adult ADHD on the categorical diagnosis level. However, rs2199430 was significantly associated with agreeableness, with minor G allele homozygotes scoring lower than A allele carriers. Whereas task performance was not affected by genotype, a significant heterosis effect limited to the ADHD group was identified for the n-back task. Heterozygotes (AG) exhibited significantly higher N200 amplitudes during both the 1-back and 2-back condition in the central electrode position Cz. Consequently, the common genetic variation of CDH13 is associated with personality traits and impacts neural processing during working memory tasks. Thus, CDH13 might contribute to symptomatic core dysfunctions of social and cognitive impairment in ADHD. KW - ADHD KW - CDH13 KW - neurodevelopment KW - executive functions KW - working memory KW - Big Five KW - agreeableness Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-245220 SN - 2073-4425 VL - 12 IS - 9 ER - TY - JOUR A1 - Rosenbaum, David A1 - Blum, Leonore A1 - Schweizer, Paul A1 - Fallgatter, Andreas J. A1 - Herrmann, Martin J. A1 - Ehlis, Ann-Christine A1 - Metzger, Florian G. T1 - Comparison of speed versus complexity effects on the hemodynamic response of the trail making test in block designs JF - Neurophotonics N2 - The use of functional near-infrared spectroscopy (fNIRS) in block designs provides measures of cortical activity in ecologically valid environments. However, in some cases, the use of block designs may be problematic when data are not corrected for performance in a time-restricted block. We sought to investigate the effects of task complexity and processing speed on hemodynamic responses in an fNIRS block design. To differentiate the effects of task complexity and processing speed, 20 subjects completed the trail making test (TMT) in two versions (TMT-A versus TMT-B) and three different speed levels (slow versus moderate versus fast). During TMT-A, subjects are asked to connect encircled numbers in numerically ascending order (1-2-3 ... ). In the more complex TMT-B, subjects are instructed to connect encircled numbers and letters in alternating ascending order (1-A-2-B ... ). To illustrate the obscuring effects of processing speed on task complexity, we perform two different analyses. First, we analyze the classical measures of oxygenated blood, and second, we analyze the measures corrected for the number of processed items. Our results show large effects for processing speed within the bilateral inferior frontal gyrus, left dorsolateral prefrontal cortex, and superior parietal lobule (SPL). The TMT contrast did not show significant effects with classical measures, although trends are observed for higher activation during TMT-B. When corrected for processed items, higher activity for TMT-B in comparison to TMT-A is found within the SPL. The results are discussed in light of recent research designs, and simple to use correction methods are suggested. (c) The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI. KW - functional near-infrared spectroscopy KW - trail making test KW - processing speed KW - task complexity Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-226982 VL - 5 IS - 4 ER - TY - JOUR A1 - Haeussinger, Florian B. A1 - Heinzel, Sebastian A1 - Hahn, Tim A1 - Schecklmann, Martin A1 - Ehlis, Ann-Christine A1 - Fallgatter, Andreas J. T1 - Simulation of Near-Infrared Light Absorption Considering Individual Head and Prefrontal Cortex Anatomy: Implications for Optical Neuroimaging JF - PLoS ONE N2 - Functional near-infrared spectroscopy (fNIRS) is an established optical neuroimaging method for measuring functional hemodynamic responses to infer neural activation. However, the impact of individual anatomy on the sensitivity of fNIRS measuring hemodynamics within cortical gray matter is still unknown. By means of Monte Carlo simulations and structural MRI of 23 healthy subjects (mean age: (25.0 +/- 2.8) years), we characterized the individual distribution of tissue-specific NIR-light absorption underneath 24 prefrontal fNIRS channels. We, thereby, investigated the impact of scalp-cortex distance (SCD), frontal sinus volume as well as sulcal morphology on gray matter volumes (V(gray)) traversed by NIR-light, i.e. anatomy-dependent fNIRS sensitivity. The NIR-light absorption between optodes was distributed describing a rotational ellipsoid with a mean penetration depth of (23.6 +/- 0.7) mm considering the deepest 5% of light. Of the detected photon packages scalp and bone absorbed (96.4 +/- 9: 7)% and V(gray) absorbed (3.1 +/- 1.8)% of the energy. The mean V(gray) volume (1.1 +/- 0.4)cm(3) was negatively correlated (r = - .76) with the SCD and frontal sinus volume (r = - .57) and was reduced by 41.5% in subjects with relatively large compared to small frontal sinus. Head circumference was significantly positively correlated with the mean SCD (r = .46) and the traversed frontal sinus volume (r = .43). Sulcal morphology had no significant impact on V(gray). Our findings suggest to consider individual SCD and frontal sinus volume as anatomical factors impacting fNIRS sensitivity. Head circumference may represent a practical measure to partly control for these sources of error variance. KW - Beer-lambert law KW - Adult head KW - Human brain KW - Spectroscopy fnirs KW - Photon migration KW - Propagation KW - Scattering KW - Model KW - Tissues KW - Media Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-142311 VL - 6 IS - 10 ER - TY - THES A1 - Ehlis, Ann-Christine T1 - Hirnelektrische Hypofrontalität bei schizophrenen Patienten und ihre Bedeutung für die Auswahl der neuroleptischen Medikation T1 - Hypofrontality in schizophrenic patients and its relevance for the choice of antipsychotic medication N2 - Hintergrund und Ziel der Untersuchung: Patienten mit schizophrenen Erkrankungen zeigen in einer Vielzahl von Untersuchungssituationen eine verminderte Funktion frontaler Hirnregionen (Hypofrontalität), die insbesondere auch den anterioren cingulären Cortex (ACC) betrifft. Verschiedene Arten antipsychotischer Medikation unterscheiden sich hinsichtlich ihrer Wirkung auf Metabolismus und Funktion des Frontalcortex, wobei es Hinweise darauf gibt, dass atypische Antipsychotika diesen Bereich des Gehirns positiv beeinflussen, während konventionelle Antipsychotika (Typika) hier nur geringe oder sogar negative Effekte zeigen. Hinsichtlich der Auswahl eines Antipsychotikums zu Beginn einer medikamentösen Behandlung gibt es bislang keine etablierten neurophysiologischen/biologischen Marker, die eine Vorhersage der Therapie-Response unter verschiedenen Arten antipsychotischer Medikation erlauben. Ziel der Studie war es daher, die Eignung der NoGo-Anteriorisierung (NGA) als Prädiktor der Therapie-Response schizophrener Patienten unter typischer bzw. atypischer Medikation zu untersuchen. Die NGA ist ein neurophysiologischer Marker, der die Funktion präfrontaler Areale einschließlich des ACC widerspiegeln soll. Unter Zuhilfenahme dieses Parameters wurde an einer Gruppe schizophrener Patienten überprüft, ob das Ausmaß der initialen Hypofrontalität eine Vorhersage der individuellen Therapie-Response erlaubt. Methoden: Es wurden 76 Patienten mit Erkrankungen aus dem schizophrenen Formenkreis zu jeweils drei Messzeitpunkten neurophysiologisch, neuropsychologisch und psychometrisch getestet. Die Baseline-Messung (t1) fand innerhalb der ersten drei Tage eines stationär-psychiatrischen Aufenthalts, die beiden Folgemessungen (t2, t3) drei bzw. sechs Wochen nach Beginn einer Therapie mit typischen (n=36) oder atypischen Antipsychotika (n=40) statt. Im Rahmen der neurophysiologischen Untersuchung führten die Patienten eine Go-NoGo-Aufgabe durch, wobei anhand der durch Go- und NoGo-Stimuli evozierten ereigniskorrelierten Potentiale individuell die NGA ermittelt wurde. Beide Behandlungsgruppen wurden aufgrund der NGA-Werte zu t1 in Patienten mit initial starker vs. schwacher Frontalhirnfunktion unterteilt (Mediansplit). Ergebnisse: Alle Patientengruppen zeigten eine signifikante Besserung der psychotischen Symptomatik im Verlauf des 6-wöchigen Untersuchungszeitraums. Außerdem hatten Atypika hypothesengemäß einen signifikant positiven Einfluss auf die Entwicklung der neuropsychologischen Testleistungen, während Typika oftmals mit einer Verschlechterung entsprechender Maße einhergingen. Atypika hatten zudem eine günstigere Wirkung auf die subjektiv erlebte Lebensqualität der Patienten. Darüber hinaus war die zu t1 erhobene NGA ein signifikanter Prädiktor der Therapie-Response. Niedrige Werte der NGA zu Beginn der Behandlung sagten dabei ein besonders gutes Ansprechen auf atypische Antipsychotika voraus, während hohe Werte der NGA zu t1 mit einer besonders deutlichen klinischen Besserung unter typischer Medikation einhergingen. Die NGA korrelierte zudem signifikant mit den neuropsychologischen Testleistungen, unterlag selbst aber keinen systematischen Veränderungen unter typischer vs. atypischer Medikation. Schlussfolgerung: Der auf der Basis früherer Untersuchungen vermutete Zusammenhang zwischen der NGA und präfrontalen Hirnfunktionen konnte anhand der vorliegenden Befunde bestätigt werden. Außerdem war aufgrund der zu Beginn einer stationär-psychiatrischen Behandlung gemessenen NGA eine signifikante Vorhersage der Therapie-Response unter typischen und atypischen Antipsychotika möglich. Die NGA könnte somit im klinischen Alltag zu einer individualisierten Entscheidungsfindung bei der Auswahl eines antipsychotischen Präparats, unter Berücksichtigung pathophysiologischer Aspekte der Erkrankung, beitragen. N2 - Background and objective: Schizophrenic patients often exhibit functional deficits in frontal cortical areas (hypofrontality), particularly within the anterior cingulate cortex (ACC). Different classes of antipsychotic medication differ with respect to their influence on function and metabolism of the frontal cortex, with a more positive effect of atypical as compared to typical compounds. Regarding the therapeutic choice of a particular antipsychotic substance, previous research efforts have not yet been able to establish neurobiological markers that are able to predict the patients’ clinical response to different kinds of antipsychotic medication. The present study, therefore, aimed at examining the NoGo-Anteriorization (NGA) as a possible predictor of the clinical response to typical and atypical antipsychotic treatment. The NGA is a neurophysiological marker that presumably reflects activation of prefrontal cortical structures, including the ACC. For the present study, a group of schizophrenic patients was examined three times in the course of a psychiatric in-patient treatment, to confirm that prefrontal cortical function is positively influenced by atypical antipsychotics, and to explore whether the amount of hypofrontality at the beginning of treatment (quantified by means of the NGA) allows for a prediction of the clinical response to both kinds of antipsychotic medication. Methods: 76 patients with schizophrenic illnesses were examined three times each, by means of neurophysiological, neuropsychological and psychometric measures. Baseline measurements (t1) were conducted within the first three days of a psychiatric in-patient treatment, follow-up measurements (t2, t3) three and six weeks after the start of a therapy with typical (n=36) or atypical antipsychotics (n=40). For the neurophysiological examination, patients performed a Go-NoGo-task, and the individual NGA was calculated on the basis of the corresponding Go- and NoGo-ERPs (event-related potentials). Moreover, the NGA at baseline was used to subdivide both treatment groups into patients with initially strong vs. weak frontal cortical function (NGA above and below group-median, respectively). Results: On a clinical level, patients in each of the four study groups improved significantly over the course of the study period. In line with previous findings, atypical antipsychotics furthermore positively influenced neuropsychological test performance, whereas typical medication often caused a decline in test scores. Similarly, atypical compounds had a more favourable impact on the patients’ self-reported quality of life. Moreover, baseline values of the NGA significantly predicted the patients’ clinical response: Low values at t1 were associated with a particularly strong improvement under atypical medication, whereas high initial values of the NGA predicted a particularly good response to typical antipsychotics. The NGA furthermore significantly correlated with neuropsychological test scores, but did not systematically change over the course of a treatment with typical vs. atypical antipsychotics. Conclusion: The present findings confirm the putative association between the NGA and prefrontal brain functions. Furthermore, the NGA at the beginning of a psychiatric in-patient treatment significantly predicted the clinical response to typical and atypical antipsychotic treatment. Since the NGA can be easily determined in clinical routine settings, it might be a useful parameter for the development of individualised treatment strategies based on pathophysiological aspects of schizophrenic illnesses. KW - Schizophrenie KW - Präfrontaler Cortex KW - Gyrus cinguli KW - Neuroleptikum KW - Ereigniskorreliertes Potenzial KW - Inhibition KW - Prädiktor KW - Neuropsychologie KW - NoGo-Anteriorisierung KW - NGA KW - Continuous Performance Test KW - CPT KW - P300 KW - Schizophrenia KW - Anterior cingulate KW - Antipsychotics KW - NoGo-Anteriorisation KW - Event-related potential Y1 - 2007 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-26566 ER - TY - JOUR A1 - Biehl, Stefanie C. A1 - Ehlis, Ann-Christine A1 - Müller, Laura D. A1 - Niklaus, Andrea A1 - Pauli, Paul A1 - Herrmann, Martin J. T1 - The impact of task relevance and degree of distraction on stimulus processing JF - BMC Neuroscience N2 - Background The impact of task relevance on event-related potential amplitudes of early visual processing was previously demonstrated. Study designs, however, differ greatly, not allowing simultaneous investigation of how both degree of distraction and task relevance influence processing variations. In our study, we combined different features of previous tasks. We used a modified 1-back task in which task relevant and task irrelevant stimuli were alternately presented. The task irrelevant stimuli could be from the same or from a different category as the task relevant stimuli, thereby producing high and low distracting task irrelevant stimuli. In addition, the paradigm comprised a passive viewing condition. Thus, our paradigm enabled us to compare the processing of task relevant stimuli, task irrelevant stimuli with differing degrees of distraction, and passively viewed stimuli. EEG data from twenty participants was collected and mean P100 and N170 amplitudes were analyzed. Furthermore, a potential connection of stimulus processing and symptoms of attention deficit hyperactivity disorder (ADHD) was investigated. Results Our results show a modulation of peak N170 amplitudes by task relevance. N170 amplitudes to task relevant stimuli were significantly higher than to high distracting task irrelevant or passively viewed stimuli. In addition, amplitudes to low distracting task irrelevant stimuli were significantly higher than to high distracting stimuli. N170 amplitudes to passively viewed stimuli were not significantly different from either kind of task irrelevant stimuli. Participants with more symptoms of hyperactivity and impulsivity showed decreased N170 amplitudes across all task conditions. On a behavioral level, lower N170 enhancement efficiency was significantly correlated with false alarm responses. Conclusions Our results point to a processing enhancement of task relevant stimuli. Unlike P100 amplitudes, N170 amplitudes were strongly influenced by enhancement and enhancement efficiency seemed to have direct behavioral consequences. These findings have potential implications for models of clinical disorders affecting selective attention, especially ADHD. KW - Selective attention KW - Working memory KW - Cognitive control KW - P100 KW - N170 KW - ADHD Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-97271 UR - http://www.biomedcentral.com/1471-2202/14/107 ER -