Finn Årup Nielsen

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We apply nine analytic methods employed currently in imaging neuroscience to simulated and actual BOLD fMRI signals and compare their performances under each signal type. Starting with baseline time series generated by a resting subject during a null hypothesis study, we compare method performance with embedded focal activity in these series of three(More)
BACKGROUND A polymorphism in the promoter region of the serotonin transporter gene (5-HTTLPR) has been associated with seasonality both in patients with seasonal affective disorder and in the general population. METHOD We used in vivo molecular imaging to measure cerebral serotonin transporter (5-HTT) binding in 57 healthy Scandinavians and related the(More)
Potentiation of serotonergic transmission increases cognitive flexibility, but can in other circumstances increase sensitivity to stressful environmental cues. The personality trait Openness to Experience reflects and is also associated with an increased risk for mood disorders. We hypothesized that the personality trait has an association with a biomarker(More)
Data The database is inspired by the hierarchical structure of BrainMap [1] with scientific articles (“bib” structures) on the highest level containing one or more experiments (“exp” structure”, corresponding to a contrast in general linear model analyses), these in turn comprising one or more locations (“loc” structures). The information on the “bib” level(More)
Analysis of fMRI time series is often performed by extracting one or more parameters for the individual voxels. Methods based, e.g., on various statistical tests are then used to yield parameters corresponding to probability of activation or activation strength. However, these methods do not indicate whether sets of voxels are activated in a similar way or(More)
Sentiment analysis of microblogs such as Twitter has recently gained a fair amount of attention. One of the simplest sentiment analysis approaches compares the words of a posting against a labeled word list, where each word has been scored for valence, — a “sentiment lexicon” or “affective word lists”. There exist several affective word lists, e.g., ANEW(More)
BACKGROUND Serotonergic dysfunction has been associated with affective disorders. High trait neuroticism, as measured on personality inventories, is a risk factor for major depression. In this study we investigated whether neuroticism is associated with serotonin 2A receptor binding in brain regions of relevance for affective disorders. METHODS(More)
Generalization can be defined quantitatively and can be used to assess the performance of principal component analysis (PCA). The generalizability of PCA depends on the number of principal components retained in the analysis. We provide analytic and test set estimates of generalization. We show how the generalization error can be used to select the number(More)
Neuroimaging studies of learning focus on brain areas where the activity changes as a function of time. To circumvent the difficult problem of model selection, we used a data-driven analytic tool, cluster analysis, which extracts representative temporal and spatial patterns from the voxel-time series. The optimal number of clusters was chosen using a(More)
The web has greatly improved the accessibility of scientific information, however the role of the web in formal scientific publishing has been debated. Some argue that the lack of persistence of web resources means that they should not be cited in scientific research. We analyze references to web resources in computer science publications, finding that the(More)