We present a method which allows the analytic determination of phase diagrams in the self-organizing map, a model for the formation of topographic projection patterns in the brain and in signal processing applications. The method only requires an ansatz for the tesselation of the data space induced by the map, not for the explicit state of the map. We analytically obtain phase diagrams for vari...

To evaluate whether hemispheric lesion distribution in multiple sclerosis is related to the uneven interhemispheric localisation of cerebral function, a 10 item self administered questionnaire evaluating hand preference and supratentorial brain MRI was obtained in 23 patients with clinically definite multiple sclerosis. The mean degree of hand preference was +74 (range -86 to +100). The median ...

The pattern formation in orientation and ocular dominance columns is one of the most investigated problems in the brain. From a known cortical structure, we build spinlike Hamiltonian models with long-range interactions of the Mexican hat type. These Hamiltonian models allow a coherent interpretation of the diverse phenomena in the visual map formation with the help of relaxation dynamics of sp...

Ocular dominance column formation in visual cortex depends on both the presence of subplate neurons and the endogenous expression of neurotrophins. Here we show that deletion of subplate neurons, which supply glutamatergic inputs to visual cortex, leads to a paradoxical increase in brain-derived neurotrophic factor mRNA in the same region of visual cortex in which ocular dominance columns are a...

Using event-related fMRI we investigated the rewarding properties of cultural objects (cars) signaling wealth and social dominance. It has been shown recently that reward mechanisms are involved in the regulation of social relations like dominance and social rank. Based on evolutionary considerations we hypothesized that sports cars in contrast to other categories of cars, e.g. limousines and s...

Functional hemispheric asymmetry is a common feature of vertebrate brain organization, yet little is known about how hemispheric dominance is implemented at the neural level. One notable example of hemispheric dominance in birds is the leading role of the left hippocampal formation in controlling navigational processes that support homing in pigeons. Relying on resting state fMRI analyses (wher...

BACKGROUND AND PURPOSE Determining language dominance with fMRI is challenging in patients with brain tumor, particularly in cases of suspected atypical language representation. Supratentorial activation patterns must be interpreted with great care when the tumor is in or near the presumed language areas, where tumor tissue or mass effect can lead to false-negative fMRI results. In this study, ...

Human brain mapping allows the systematic assessment of interindividual differences in functional brain anatomy. Functional transcranial Doppler sonography (fTCD) is an imaging tool that allows for fast and mobile assessment of hemispheric lateralization of task-related brain activation. It is ideal to screen large cohorts of subjects. The goal of the present study was to investigate whether fT...

There are striking behavioural and neural parallels between the acquisition of speech in humans and song learning in songbirds. In humans, language-related brain activation is mostly lateralised to the left hemisphere. During language acquisition in humans, brain hemispheric lateralisation develops as language proficiency increases. Sleep is important for the formation of long-term memory, in h...