University of Fribourg

About: University of Fribourg is a education organization based out in Fribourg, Freiburg, Switzerland. It is known for research contribution in the topics: Population & Context (language use). The organization has 6040 authors who have published 14975 publications receiving 542500 citations. The organization is also known as: UNIFR & Universität Freiburg.

Pathways from weight fluctuations to metabolic diseases: focus on maladaptive thermogenesis during catch-up fat.

Abstract: It has long been known that obesity is a high risk factor for cardiovascular diseases. In more recent years, the analysis of several large epidemiological databases has also revealed that, independently of excess weight, large fluctuations in body weight at some point earlier in life represent an independent risk factor for type 2 diabetes and hypertension-two major contributors to cardiovascular diseases. High cardiovascular morbidity and mortality have indeed been reported in men and women who in young adulthood experienced weight fluctuations (involving the recovery of body weight after weight loss due to disease, famine or voluntary slimming), or when weight fluctuations occurred much earlier in life and involved catch-up growth after fetal or neonatal growth retardation. This paper addresses the pathways from weight fluctuations to chronic metabolic diseases by focusing on the phenomenon of accelerated fat recovery (ie catch-up fat) after weight loss or growth retardation. Arguments are put forward that, during catch-up growth or weight recovery on our modern refined foods, the mechanisms of adaptive thermogenesis that regulate catch-up fat are pushed beyond the limits for which they were meant to operate and turn maladaptive. The consequences are enhanced susceptibilities towards skeletal muscle insulin resistance and overactive sympathetic activity, both of which are major contributors to the pathogenesis of chronic metabolic diseases. Since weight fluctuation earlier in life (independently of excess weight later in life) is an independent risk factor for metabolic diseases, the mechanisms by which body fat is acquired would seem to be at least as important as the consequences of excess fat per se in the pathogenesis of diabetes, hypertension and cardiovascular diseases.

Cognitive humor processing: different logical mechanisms in nonverbal cartoons--an fMRI study.

Abstract: Although recent fMRI studies on humor have begun to elucidate cognitive and affective neural correlates, they weren't able to distinguish between different logical mechanisms or steps of humor processing, i.e., the detection of an incongruity and its resolution. This fMRI study aimed to focus in more detail on cognitive humor processing. In order to investigate pure incongruity resolution without preprocessing steps, nonverbal cartoons differing in their logical mechanisms were contrasted with nonhumorous pictures containing an irresolvable incongruity. The logical mechanisms were: (1) visual puns (visual resemblance, PUNs); (2) semantic cartoons (pure semantic relationships, SEMs); and (3) Theory of Mind cartoons (which require additionally mentalizing abilities, TOMs). Thirty cartoons from each condition were presented to 17 healthy subjects while acquiring fMR images. The results reveal a left-sided network involved in pure incongruity resolution: e.g., temporo-parietal junction, inferior frontal gyrus and ventromedian prefrontal cortex. These areas are also involved in processing of SEMs, whereas PUNs show more activation in the extrastriate cortex and TOMs show more activation in so-called mentalizing areas. Processing of pictures containing an irresolvable incongruity evokes activation in the rostral cingulate zone, which might reflect error processing. We conclude that cognitive processing of different logical mechanisms depends on separate neural networks.

Auditory feedback blocks memory benefits of cueing during sleep

Abstract: It is now widely accepted that re-exposure to memory cues during sleep reactivates memories and can improve later recall. However, the underlying mechanisms are still unknown. As reactivation during wakefulness renders memories sensitive to updating, it remains an intriguing question whether reactivated memories during sleep also become susceptible to incorporating further information after the cue. Here we show that the memory benefits of cueing Dutch vocabulary during sleep are in fact completely blocked when memory cues are directly followed by either correct or conflicting auditory feedback, or a pure tone. In addition, immediate (but not delayed) auditory stimulation abolishes the characteristic increases in oscillatory theta and spindle activity typically associated with successful reactivation during sleep as revealed by high-density electroencephalography. We conclude that plastic processes associated with theta and spindle oscillations occurring during a sensitive period immediately after the cue are necessary for stabilizing reactivated memory traces during sleep.