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Functional magnetic resonance imaging (fMRI) hypothesis testing based on the blood oxygenation level dependent (BOLD) contrast mechanism typically involves a search for a positive effect during a specific task relative to a control state. However, aside from positive BOLD signal changes there is converging evidence that neuronal responses within various(More)
While the relationship between sensory stimulation and tasks and the size of the cortical activations is generally unknown, the visual modality offers a unique possibility of an experimental manipulation of stimulus size-related increases of the spatial extent of cortical activation even during the earliest activity in the retinotopically organized primary(More)
Somatosensory signals modulate activity throughout a widespread network in both of the brain hemispheres: the contralateral as well as the ipsilateral side of the brain relative to the stimulated limb. To analyze the ipsilateral somatosensory brain areas that are engaged during limb stimulation, we performed functional magnetic resonance imaging (fMRI) in(More)
Development of the fetal autonomic nervous system's integrative capacity in relation to gestational age and emerging behavioral pattern is reflected in fetal heart rate patterns. Conventional indices of vagal and sympathetic rhythms cannot sufficiently reflect their complex interrelationship. Universal behavioral indices of developing complex systems may(More)
Following stroke, many patients suffer from chronic motor impairment and reduced somatosensation in the stroke-affected body parts. Recent experimental studies suggest that temporary functional deafferentation (TFD) of parts of the stroke-affected upper limb or of the less-affected contralateral limb might improve the sensorimotor capacity of the(More)
Repeated auditory stimulation results usually in a response decrement of event-related potential components. In the current study, we investigated the impact of the interstimulus interval (ISI) on the response decrement. Healthy subjects were stimulated with trains of five tones, with an ISI of 600, 1,200, or 1,800 ms within the trains. Auditory evoked(More)
Studies on attention to tactile stimuli have produced conflicting results concerning the possibility and/or direction of modulation of early somatosensory-evoked fields (SEFs). To evaluate sources of these conflicting results, the same subjects performed four different tasks in which the stimulation site, type, and intensity were kept constant. Twelve(More)
In the present study, responses of the somatosensory cortex to sensory input of ten human volunteers were investigated during a one-back task with different conditions of attention. During an condition of attention subjects were requested to detect a predefined sequence of tactile stimuli applied to two different fingers of the dominant hand while a series(More)
Several functional brain imaging studies of pain using positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) have shown that painful stimulation causes activation of different brain areas. The aim of the present study was to develop and implement painful stimulation of the trigeminal nerve, which can be applied with(More)
The advent of methods to investigate network dynamics has led to discussion of whether somatosensory inputs are processed in serial or in parallel. Both hypotheses are supported by DCM analyses of fMRI studies. In the present study, we revisited this controversy using DCM on magnetoencephalographic (MEG) data during somatosensory stimulation. Bayesian model(More)