University of Cologne

About: University of Cologne is a education organization based out in Cologne, Germany. It is known for research contribution in the topics: Population & Gene. The organization has 32050 authors who have published 66350 publications receiving 2210092 citations. The organization is also known as: Universität zu Köln & Universitatis Coloniensis.

Minds made for sharing: Initiating joint attention recruits reward-related neurocircuitry

Abstract: The ability and motivation to share attention is a unique aspect of human cognition. Despite its significance, the neural basis remains elusive. To investigate the neural correlates of joint attention, we developed a novel, interactive research paradigm in which participants' gaze behavior-as measured by an eye tracking device-was used to contingently control the gaze of a computer-animated character. Instructed that the character on screen was controlled by a real person outside the scanner, 21 participants interacted with the virtual other while undergoing fMRI. Experimental variations focused on leading versus following the gaze of the character when fixating one of three objects also shown on the screen. In concordance with our hypotheses, results demonstrate, firstly, that following someone else's gaze to engage in joint attention resulted in activation of anterior portion of medial prefrontal cortex (MPFC) known to be involved in the supramodal coordination of perceptual and cognitive processes. Secondly, directing someone else's gaze toward an object activated the ventral striatum which-in light of ratings obtained from participants-appears to underlie the hedonic aspects of sharing attention. The data, therefore, support the idea that other-initiated joint attention relies upon recruitment of MPFC previously related to the "meeting of minds." In contrast, self-initiated joint attention leads to a differential increase of neural activity in reward-related brain areas, which might contribute to the uniquely human motivation to engage in the sharing of experiences.

Standardization and Interlaboratory Reproducibility Assessment of Pulsed-Field Gel Electrophoresis-Generated Fingerprints of Acinetobacter baumannii

Abstract: A standard procedure for pulsed-field gel electrophoresis (PFGE) of macrorestriction fragments of Acinetobacter baumannii was set up and validated for its interlaboratory reproducibility and its potential for use in the construction of an Internet-based database for international monitoring of epidemic strains. The PFGE fingerprints of strains were generated at three different laboratories with ApaI as the restriction enzyme and by a rigorously standardized procedure. The results were analyzed at the respective laboratories and also centrally at a national reference institute. In the first phase of the study, 20 A. baumannii strains, including 3 isolates each from three well-characterized hospital outbreaks and 11 sporadic strains, were distributed blindly to the participating laboratories. The local groupings of the isolates in each participating laboratory were identical and allowed the identification of the epidemiologically related isolates as belonging to three clusters and identified all unrelated strains as distinct. Central pattern analysis by using the band-based Dice coefficient and the unweighted pair group method with mathematical averaging as the clustering algorithm showed 95% matching of the outbreak strains processed at each local laboratory and 87% matching of the corresponding strains if they were processed at different laboratories. In the second phase of the study, 30 A. baumannii isolates representing 10 hospital outbreaks from different parts of Europe (3 isolates per outbreak) were blindly distributed to the three laboratories, so that each laboratory investigated 10 epidemiologically independent outbreak isolates. Central computer-assisted cluster analysis correctly identified the isolates according to their corresponding outbreak at an 87% clustering threshold. In conclusion, the standard procedure enabled us to generate PFGE fingerprints of epidemiologically related A. baumannii strains at different locations with sufficient interlaboratory reproducibility to set up an electronic database to monitor the geographic spread of epidemic strains.