Author name cluster

Andreas Fritsche

Possible papers associated with this exact author name in Arrow. This page groups case-insensitive exact name matches and is not a full identity disambiguation profile.

5 papers

1 author row

YNIMG Journal 2016 Journal Article

Specific white matter tissue microstructure changes associated with obesity

Stephanie Kullmann
Martina F. Callaghan
Martin Heni
Nikolaus Weiskopf
Klaus Scheffler
Hans-Ulrich Häring
Andreas Fritsche
Ralf Veit

Obesity-related structural brain alterations point to a consistent reduction in gray matter with increasing body mass index (BMI) but changes in white matter have proven to be more complex and less conclusive. Hence, more recently diffusion tensor imaging (DTI) has been employed to investigate microstructural changes in white matter structure. Altogether, these studies have mostly shown a loss of white matter integrity with obesity-related factors in several brain regions. However, the variety of these obesity-related factors, including inflammation and dyslipidemia, resulted in competing influences on the DTI indices. To increase the specificity of DTI results, we explored specific brain tissue properties by combining DTI with quantitative multi-parameter mapping in lean, overweight and obese young adults. By means of multi-parameter mapping, white matter structures showed differences in MRI parameters consistent with reduced myelin, increased water and altered iron content with increasing BMI in the superior longitudinal fasciculus, anterior thalamic radiation, internal capsule and corpus callosum. BMI-related changes in DTI parameters revealed mainly alterations in mean and axial diffusivity with increasing BMI in the corticospinal tract, anterior thalamic radiation and superior longitudinal fasciculus. These alterations, including mainly fiber tracts linking limbic structures with prefrontal regions, could potentially promote accelerated aging in obese individuals leading to an increased risk for cognitive decline.

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YNICL Journal 2014 Journal Article

Reduced cortical thickness associated with visceral fat and BMI

Ralf Veit
Stephanie Kullmann
Martin Heni
Jürgen Machann
Hans-Ulrich Häring
Andreas Fritsche
Hubert Preissl

Structural brain imaging studies have shown that obesity is associated with widespread reductions in gray matter (GM) volume. Although the body mass index (BMI) is an easily accessible anthropometric measure, substantial health problems are more related to specific body fat compartments, like visceral adipose tissue (VAT). We investigated cortical thickness measures in a group of 72 healthy subjects (BMI range 20-35 kg/m(2), age range 19-50 years). Multiple regression analyses were performed using VAT and BMI as predictors and age, gender, total surface area and education as confounds. BMI and VAT were independently associated with reductions in cortical thickness in clusters comprising the left lateral occipital area, the left inferior temporal cortex, and the left precentral and inferior parietal area, while the right insula, the left fusiform gyrus and the right inferior temporal area showed a negative correlation with VAT only. In addition, we could show significant reductions in cortical thickness with increasing VAT adjusted for BMI in the left temporal cortex. We were able to detect widespread cortical thinning in a young to middle-aged population related to BMI and VAT; these findings show close resemblance to studies focusing on GM volume differences in diabetic patients. This may point to the influence of VAT related adverse effects, like low-grade inflammation, as a potentially harmful factor on brain integrity already in individuals at risk of developing diabetes, metabolic syndromes and arteriosclerosis.

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YNIMG Journal 2012 Journal Article

Neuronal correlates of reduced memory performance in overweight subjects

Krunoslav T. Stingl
Stephanie Kullmann
Caroline Ketterer
Martin Heni
Hans-Ulrich Häring
Andreas Fritsche
Hubert Preissl

There is growing evidence that excessive body weight correlates with impaired cognitive performance like executive function, attention and memory. In our study, we applied a visual working memory task to quantify associations between body weight and executive function. In total, 34 lean (BMI 22±2. 1kg/m2) and 34 obese (BMI 30. 4±3. 2kg/m2) subjects were included. Magnetic brain activity and behavioral responses were recorded during a one-back visual memory task with food and non-food pictures, which were matched for color, size and complexity. Behavioral responses (reaction time and accuracy) were reduced in obese subjects independent of the stimulus category. Neuronal activity at the source level showed a positive correlation between the right dorsolateral prefrontal cortex (DLPFC) activity and BMI only for the food category. In addition, a negative correlation between BMI and neuronal activity was observed in the occipital area for both categories. Therefore we conclude that increased body weight is associated with reduced task performance and specific neuronal changes. This altered activity is probably related to executive function as well as encoding and retrieval of information.

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YNIMG Journal 2010 Journal Article

The temporal sequence of magnetic brain activity for food categorization and memorization — an exploratory study

Krunoslav T. Stingl
Maja Rogić
Katarína Stingl
Carlos Canova
Otto Tschritter
Christoph Braun
Andreas Fritsche
Hubert Preissl

The importance of food stimuli for all living organisms is defined by their relevance for survival. Therefore, visual processing of food stimuli is influenced by many factors, such as cultural and societal background. In this magnetoencephalography (MEG) study, we examined the categorization and memorization of visual food and non-food stimuli in lean subjects, using a one-back working memory task. We found an increase in neural activity in several different regions of the brain elicited by food stimuli in comparison to non-food stimuli. The first observed significant difference was found in low-level visual areas as early as 120ms after stimulus onset. The stimulus category of the previous picture did not influence this effect. However, preceding stimuli modulated behavioral measures (reaction time and accuracy of responses) and later components of the evoked responses around 350ms. The evoked magnetic field of this late component showed a significant increase inactivity in the temporal cortex for food versus non-food objects. This late component exhibited a significant correlation with the reaction time. The difference of category-specific effects in the early components and the behavioral modulation of late components could be useful for further investigations of the cortical activity in response to food stimuli, e. g. in subjects with eating disorders or obesity.

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YNIMG Journal 2006 Journal Article

Subjective feeling of appetite modulates brain activity

Katarína Porubská
Ralf Veit
Hubert Preissl
Andreas Fritsche
Niels Birbaumer

Obesity and overweight are important risk factors for the development of diabetes mellitus type 2 and associated chronic diseases, and therefore, they have become serious global problems in the western and developed countries. But little is known about the neuroanatomical correlates of eating behavior and its influences on the central nervous processing in humans. We used functional magnetic resonance imaging (fMRI) to measure the cortical activation in 12 lean healthy humans during visual stimulation with food-related and nonfood pictures after a fasting period of at least 5 h. Compared to the nonfood pictures, the food stimuli elicited a significantly greater activity in the left orbitofrontal cortex and the insular/opercular cortex bilaterally with a stronger focus on the left side. Subjective ratings of appetite during the presentation of food-related stimuli modulated the activity in the insula bilaterally, the left operculum and the right putamen. These results provide further insights in the central nervous processing of food relevant stimuli in humans, specifically with respect to the subjective experience of appetite.

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