Compulsivity predicts fronto striatal activation in severely anorectic individuals.

Anorexia nervosa is a severe illness and shows one of the highest death rates among psychiatric or psychosomatic diseases. However, despite several lines of research, the etiology of this disease is still unknown. One of those features is the rigidity of behaviors, for example, controlling of weight and pursuing of thinness, that often meets the criteria for obsessive-compulsive behavior. In this study, it was investigated whether the clinical feature of compulsivity in anorexia nervosa patients relates to regional brain activation. Using functional magnetic resonance imaging, 12 severely anorectic women were compared to 12 normal-weight female individuals following a cue-reactivity paradigm. Cues comprised food cues of high and low calorie content as well as eating-related utensils. Voxel-based morphometric analysis indicated significantly overall reduced gray matter volume and significantly increased cerebrospinal fluids in anorexia nervosa (AN) patients, which was controlled for in subsequent analyses. Following the high-calorie stimulation, AN patients activated the right caudate body and right precuneus, whereas control subjects did not show significant regional activations. In both other conditions, low-calorie foods and eating utensils, regional brain activations did not survive FDR thresholds. During the high-calorie condition, compulsivity, that is, the subscore "obsessive thoughts," predicted activation of the superior frontal gyrus [Brodmann areas (BA) 10], inferior frontal gyrus, anterior cingulate cortex (BA 32), cingulate gyrus (BA 24), caudate body, cuneus, pre- and postcentral gyrus. The subscore "compulsive acts" correlated with activation of the claustrum during the high-calorie condition and predicted a number of deactivations of frontal and temporal regions. We conclude that in severely anorectic individuals, the degree of compulsivity predicts activation and deactivation of the fronto-striatal pathway.

[Group therapeutic concept for chronic tinnitus]. / Gruppentherapeutische Ansätze bei chronischem Tinnitus.

The aim of this article is to show an established group therapeutic concept for chronic tinnitus. The treatment of chronic tinnitus is intended to improve the way patients cope with tinnitus but it does not eliminate it. It means that patients learn how to reduce the impairment they are experiencing. Patients with tinnitus are supported in the process of habituation through the treatment. Multimodal cognitive behavioral therapeutic interventions in a group setting are particularly helpful because they may demonstrate differences in the influence of cognitive processes on the emotional perception of the tinnitus between the patients. Psychological factors like emotional support through other patients and learning from other examples can ease the process of internalizing coping strategies. Psychological processes seem to be of particular importance. Those processes can have an effect on concentration, appraisal, and coping with the tinnitus. Progressive muscle relaxation using Jacobson's technique, physical therapy, education via lectures, training of selective attention and change of appraisal, mental attitude and behavior concerning the tinnitus are the main factors in tinnitus therapy and can enable tinnitus patients to decrease their psychological strain.

Brain activation responses to subliminal or supraliminal rectal stimuli and to auditory stimuli in irritable bowel syndrome.

Visceral hypersensitivity in irritable bowel syndrome (IBS) has been associated with altered cerebral activations in response to visceral stimuli. It is unclear whether these processing alterations are specific for visceral sensation. In this study we aimed to determine by functional magnetic resonance imaging (fMRI) whether cerebral processing of supraliminal and subliminal rectal stimuli and of auditory stimuli is altered in IBS. In eight IBS patients and eight healthy controls, fMRI activations were recorded during auditory and rectal stimulation. Intensities of rectal balloon distension were adapted to the individual threshold of first perception (IPT): subliminal (IPT -10 mmHg), liminal (IPT), or supraliminal (IPT +10 mmHg). IBS patients relative to controls responded with lower activations of the prefrontal cortex (PFC) and anterior cingulate cortex (ACC) to both subliminal and supraliminal stimulation and with higher activation of the hippocampus (HC) to supraliminal stimulation. In IBS patients, not in controls, ACC and HC were also activated by auditory stimulation. In IBS patients, decreased ACC and PFC activation with subliminal and supraliminal rectal stimuli and increased HC activation with supraliminal stimuli suggest disturbances of the associative and emotional processing of visceral sensation. Hyperreactivity to auditory stimuli suggests that altered sensory processing in IBS may not be restricted to visceral sensation.

[Integrated intensive treatment of tinnitus: method and initial results]. / Integrierte Tinnitusintensivbehandlung: Konzept und erste praktische Erfahrungen.

In recent years, no major advances have been made in understanding the mechanisms underlying the development of tinnitus. Hence, the present therapeutic strategies aim at decoupling the subconscious from the perception of tinnitus. Mindful of the lessons drawn from existing tinnitus retraining and desensitisation therapies, a new integrated day hospital strategy of treatment lasting 7-14 days has been developed at the Charité Hospital and is presented in the present paper. The strategy for treating tinnitus in the proximity of patient domicile is designed for patients who feel disturbed in their world of perception and their efficiency due to tinnitus and give evidence of mental and physical strain. In view of the etiologically non-uniform and multiple events connected with tinnitus, consideration was also given to the fact that somatic and psychosocial factors are equally involved. Therefore, therapy should aim at diagnosing and therapeutically influencing those psychosocial factors that reduce the hearing impression to such an extent that the affected persons suffer from strain. The first results of therapy-dependent changes of 46 patients suffering from chronic tinnitus are presented. The data were evaluated before and after 7 days of treatment and 6 months after the end of treatment. Immediately after the treatment, the scores of both the tinnitus questionnaire (Goebel and Hiller) and the subscales improved significantly. These results were maintained during the 6-month post-treatment period and even improved.

Pitfalls in the clustering of neuroimage data and improvements by global optimization strategies.

In this paper, we examined three vector quantization (VQ) methods used for the unsupervised classification (clustering) of functional magnetic resonance imaging (fMRI) data. Classification means that each brain volume element (voxel), according to a given scanning raster, was assigned to one group of voxels based on similarity of the fMRI signal patterns. It was investigated how the VQ methods can isolate a cluster that describes the region involved in a particular brain function. As an example, word processing was stimulated by a word comparison task. VQ analysis methodology was verified using simulated fMRI response patterns. It was demonstrated in detail that VQ based on global rather than local optimization of the objective function yielded a higher performance. Performance was measured in statistically relevant series of VQ attempts using several indices for goodness, reliability and efficiency of VQ solutions. Furthermore, it was shown that a poor local optimization caused either an underestimation or an overestimation of the stimulus-induced brain activation. However, this was not observed if the cluster analysis was based upon a global optimization strategy.

fMRI during word processing in dyslexic and normal reading children.

The present study addresses phonological processing in children with developmental dyslexia. Following the hypothesis of a core deficit of assembled phonology in dyslexia a set of hierarchically structured tasks was applied that specifically control for different kinds of phonological coding (assembled versus addressed phonological strategies). Seventeen developmental dyslexics and 17 normal reading children were scanned during four different tasks: (1) passive viewing of letter strings (control condition), (2) passive reading of non-words, (3) passive reading of legal words, and (4) a task requiring phonological transformation. Statistical analysis of the data was performed using statistical parametric mapping (SPM96). Comparison of patterns of activation in dyslexic and normal reading children revealed significant differences in Broca's area and the left inferior temporal region for both, non-word reading and the phonological transformation task. The present data provide new evidence for alteration of the phonological system in dyslexic children, and in particular, the system that mediates assembled phonological coding.