Université de Fribourg

Effects of lactate on the early visual cortex of non-human primates, investigated by pharmaco-MRI and neurochemical analysis

Pföstl, Veronika von ; Li, Juan ; Zaldivar, Daniel ; Goense, Jozien ; Zhang, Xiaozhe ; Serr, Nadine ; Logothetis, Nikos K. ; Rauch, Alexander

In: NeuroImage, 2012, vol. 61, no. 1, p. 98–105

In contrast to the limited use of functional magnetic resonance imaging (fMRI) in clinical diagnostics, it is currently a mainstay of neuroimaging in clinical and basic brain research. However, its non-invasive use in combination with its high temporal and spatial resolution would make fMRI a perfect diagnostic tool. We are interested in whether a pharmacological challenge imposed on the brain...

Université de Fribourg

Measuring multiple neurochemicals and related metabolites in blood and brain of the rhesus monkey by using dual microdialysis sampling and capillary hydrophilic interaction chromatography–mass spectrometry

Li, Juan ; Pföstl, Veronika von ; Zaldivar, Daniel ; Zhang, Xiaozhe ; Logothetis, Nikos ; Rauch, Alexander

In: Analytical and Bioanalytical Chemistry, 2012, p. -

In vivo measurement of multiple functionally related neurochemicals and metabolites (NMs) is highly interesting but remains challenging in the field of basic neuroscience and clinical research. We present here an analytical method for determining five functionally and metabolically related polar substances, including acetylcholine (quaternary ammonium), lactate and pyruvate (organic acids), as...

Université de Fribourg

Temporal kernel CCA and its application in multimodal neuronal data analysis

Bießmann, Felix ; Meinecke, Contact Information, Frank C. ; Gretton, Contact Information, Arthur ; Rauch, Alexander ; Rainer, Gregor ; Logothetis, Nikos K. ; Müller, Klaus-Robert

In: Machine Learning, 2010, vol. 79, no. 1-2, p. 5-27

Data recorded from multiple sources sometimes exhibit non-instantaneous couplings. For simple data sets, cross-correlograms may reveal the coupling dynamics. But when dealing with high-dimensional multivariate data there is no such measure as the cross-correlogram. We propose a simple algorithm based on Kernel Canonical Correlation Analysis (kCCA) that computes a multivariate temporal filter...