A silent event-related functional MRI technique for brain activation studies without interference of scanner acoustic noise
Autor: | Su Xu, Almut Engelien, Emily Stern, David Silbersweig, Wolfgang Engelien, Yihong Yang |
---|---|
Rok vydání: | 2000 |
Předmět: |
Scanner
Time Factors Computer science Stimulus (physiology) Auditory cortex Brain mapping Gyrus Reference Values medicine Humans Radiology Nuclear Medicine and imaging Least-Squares Analysis Evoked Potentials Cerebral Cortex Brain Mapping business.industry Dynamic range Hemodynamics Brain Magnetic Resonance Imaging Noise medicine.anatomical_structure Acoustic Stimulation Tonotopy Telecommunications business Artifacts Neuroscience Algorithms |
Zdroj: | Magnetic resonance in medicine. 43(2) |
ISSN: | 0740-3194 |
Popis: | A new data acquisition method for silent, event-related functional MRI in which scanner acoustic noise does not interfere with brain activation is introduced and evaluated in an auditory tonotopic mapping experiment. This method takes into account the hemodynamic-response characteristics of the brain during activation, associated with both task performance and scanner noise. A data acquisition scheme was designed to collect task-induced brain activation signals without interference of scanner noise on stimulus delivery or on the measured response. The advantages of the technique were demonstrated in a tonotopic mapping experiment of human auditory cortex. Tonotopic maps obtained by the technique in normal subjects showed distinct spatial shifts of the activation foci in the lateral part of Heschl's gyrus with changing stimulus frequency, whereas no systematic shift was shown in a conventional event-related experiment using the same stimulation paradigm. Signal change in the activation foci with the new technique was 54% larger than with the conventional technique, suggesting an increased dynamic range of the signal change associated with task-induced brain activation under silent conditions. |
Databáze: | OpenAIRE |
Externí odkaz: |