TY  - THES
A1  - Beck, Stefanie
T1  - Visuelles Arbeitsgedächtnis bei Patienten mit bipolarer Störung - eine Untersuchung mit funktioneller Nah-Infrarot Spektroskopie
T1  - Visual working memory in patients with bipolar depression - a study with functional near-infrared spectroscopy
N2  - Beeinträchtigungen des Arbeitsgedächtnisses und der präfrontalen Hirnaktivität (Hypofrontalität) sind Anwärter für Endophänotypen für bipolare Störungen. Diese Studie untersuchte zum ersten Mal manisch-depressive Patienten (n=14) mit einer Arbeitsgedächtnisaufgabe, die verschiedene Prozesse (Speicherung und Abgleich) und verschiedene Komponenten (objektbezogenes und visuell-räumliches) beinhaltete. Mit Hilfe der funktionellen Nah-Infrarot Spektroskopie wurde die neuronale Aktivität über dem präfrontalen Kortex erfasst. Bei der Kontrollgruppe, die der Patientengruppe vergleichbar war, zeigten Veränderungen von oxygeniertem und deoxygeniertem Hämoglobin eine Zunahme der Aktivität im ventero-lateralen, im dorso-lateralen und superioren präfrontalen Kortex in der objektbezogenen und visuell-räumlichen Arbeitsgedächtnisaufgabe im Vergleich zur Kontrollaufgabe. Obwohl sich die kognitive Leistung (Anzahl der korrekten Antworten und Reaktionszeit) zwischen den beiden Gruppen nicht unterschied, zeigte die Patientengruppe eine verminderte Gehirnaktivität während der Speicherphase der Arbeitsgedächtnisaufgaben. Die fNIRS kann als valides, leicht zu handhabendes, billiges und schnelles Mittel verwendet werden um (verminderte) präfrontale kortikale Aktivität zu messen.
N2  - Altered working memory and prefrontal brain activity (hypofrontality) are candidate endophenotypes for bipolar disorder. The present study investigated for the first time BI patients (n=14) in a working memory task including different processes (storage and matching) and components (object and spatial visual) with functional near-infrared spectroscopy (fNIRS) over prefrontal cortex. In healthy controls (n=14) comparable to the patient group, changes of oxygenated and deoxygenated haemoglobin indicated increased ventro-lateral, dorso-lateral prefrontal and superior frontal cortex activity for object and spatial visual working memory storage as compared to the control condition. Altough cognitive functioning (number of correct answers and reaction-time) was comparable between the two groups, the patient group showed diminished brain activity in the working memory conditions. fNIRS can be considered as a valid, easy manageable, low cost and rapid tool for measuring (diminished) prefrontal cortex functions.
KW  - Depression
KW  - funktionelle Nah-Infrarot Spektroskopie
KW  - bipolare Störung
KW  - manisch-depressive Störung
KW  - Arbeitsgedächtnis
KW  - exekutive Funktion
KW  - functional near-infrared spectroscopy
KW  - functional neuroimaging
KW  - bipolar disorder
KW  - working memory
KW  - executive functions
Y1  - 2010
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-55627
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  -