Publications by authors named "Lars Haab"

The in-vivo optical imaging of the cortical surface provides the ability to record different types of biophysiological signals, e.g., structural information, intrinsic signals, like blood oxygenation coupled reflection changes as well as extrinsic properties of voltage sensitive probes, like fluorescent voltage-sensitive dyes.

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Recent work has shown that sharp spectral edges in acoustic stimuli might have advantageous effects in the treatment of tonal tinnitus. In the course of this paper, we evaluate the long-term effects of spectrally notched hearing aids on the subjective tinnitus distress. By merging recent experimental work with a computational tinnitus model, we modified the commercially available behind-the-ear hearing aids so that a frequency band of 0.

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Video motion magnification forms a relatively novel family of visualization techniques, that aim to magnify imperceivably small motions in videos. The most prominent techniques are based on Eulerian video processing and local phase shifting, which modify pixel time courses, rather than relying on explicit motion estimation.In this work, we show that under ideal conditions in the context of psychophysiological experiments, a Lagrangian motion magnification approach based on dense optical flow estimation, can be superior to Eulerian motion magnification strategies.

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Functional optical imaging (OI) of intrinsic signals (like blood oxygenation coupled reflection changes) and of extrinsic properties of voltage sensitive probes (like voltage-sensitive dyes (VSD)) forms a group of invasive neuroimaging techniques, that possess up to date the highest temporal and spatial resolution on a meso- to macroscopic scale. There are different sources that contribute to the OI signal of which many are noise. In our previous works, we have used dense optical flow for the reduction of movement artefacts.

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Functional Optical Imaging (OI) through the opened skull forms a group of Neuroimaging techniques characterized by a high temporal and spatial resolution on a meso-to macroscopic scale. State of the art OI experiments are generally difficult to execute, with a very timely surgical preparation preceding the experiment, that requires a skilled surgeon to mount a sealed imaging chamber onto the skull. The chamber reduces brain pulsation artifacts and swelling of the brain through movement restriction.

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Functional optical imaging (OI) of intrinsic signals (like blood oxygenation coupled reflection changes) and of extrinsic properties of voltage sensitive probes (like voltage-sensitive dyes (VSD)) forms a group of neuroimaging techniques that possess up to date highest temporal and spatial resolution on a meso-to macroscopic scale. An inherent problem of OI is a very low signal to noise ratio (SNR), which restricts the recordings to be completely motionless and requires detailed knowledge of the properties of the different noise sources. In our experiments we performed a durectomy and did not use an imaging chamber to allow us future joint electroencephalography-optical imaging (EEG-OI) measures, which resulted in movement artifacts.

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Recent studies have focused on modeling the response of the early auditory processing stages to sound stimuli. However, the influence of sound on the higher stages like the auditory thalamus are not well identified. To understand how different sound stimuli affect the response of neurons in these higher stages, it is necessary to model the auditory pathway from the auditory nerve (AN) through the different stages up to the cortex.

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During the last years, the demand of accurate diagnostic tools for individualized tinnitus treatment gradually increased. Today several different psychometric instruments for the estimation of the patients degree of decompensation with clinical relevance have emerged. All of these tools are questionnaires for a subjective self-assessment and have deficits in comparability due to severe differences in their factor structure in the anamnesis.

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Multiple studies demonstrate the influence of the limbic system on the processing of sensory events and attentional guidance. But the mechanisms involved therein are yet not entirely clear. The close connection of handling incoming sensory information and memory retrieval, like in the case of habituation towards insignificant stimuli, suggests a crucial impact of the hippocampus on the direction of attention.

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For social species nonverbal communication by assessment of emotion expression is crucial for building up and maintaining social structures. In humans, body language not only includes gestures but also a variety of facial expressions. Negative associated facial expressions, e.

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About 93% of healthy subjects suffer from tinnituslike symptoms when deprived of auditory stimuli, e.g., in a sound-proof chamber.

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Auditory evoked cortical potentials (AECPs) have been consolidated as a diagnostic tool in audiology. Further applications of this technique are in experimental neuropsychology, neuroscience, and psychiatry, e.g.

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The study of tinnitus has become of great interest due to the increasing number and severity of cases reported worldwide. To cope with such situation, many experimental and theoretical studies have been dedicated to gain deeper insight into the neurophysiological mechanisms involved in the tinnitus decompensation. In this direction, some of the most influential tinnitus models have emphasized the link between selective attention and the tinnitus decompensation.

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Auditory evoked cortical potentials (AECP) are well established as diagnostic tool in audiology and gain more and more impact in experimental neuropsychology, neuro-science, and psychiatry, e.g., for the attention deficit disorder, schizophrenia, or for studying the tinnitus decompensation.

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