title: Functional diffusion tensor imaging at 3 Tesla.
abstract: In a previous study we reported on a non-invasive functional diffusion tensor imaging (fDTI) method to measure neuronal signals directly from subtle changes in fractional anisotropy along white matter tracts. We hypothesized that these fractional anisotropy changes relate to morphological changes of glial cells induced by axonal activity. In the present study we set out to replicate the results of the previous study with an improved fDTI scan acquisition scheme. A group of twelve healthy human participants were scanned on a 3 Tesla MRI scanner. Activation was revealed in the contralateral thalamo-cortical tract and optic radiations during tactile and visual stimulation, respectively. Mean percent signal change in FA was 3.47% for the tactile task and 3.79% for the visual task, while for the MD the mean percent signal change was only -0.10 and -0.09%. The results support the notion of different response functions for tactile and visual stimuli. With this study we successfully replicated our previous findings using the same types of stimuli but on a different group of healthy participants and at different field-strength. The successful replication of our first fDTI results suggests that the non-invasive fDTI method is robust enough to study the functional neural networks in the human brain within a practically feasible time period.
authors.affiliation: 1Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht Utrecht, Netherlands.
authors.forename: René C W
authors.initials: RC
authors.lastname: Mandl
authors.affiliation: 1Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht Utrecht, Netherlands.
authors.forename: Hugo G
authors.initials: HG
authors.lastname: Schnack
authors.affiliation: 2Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour Centre for Cognitive Neuroimaging Nijmegen, Netherlands.
authors.forename: Marcel P
authors.initials: MP
authors.lastname: Zwiers
authors.affiliation: 1Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht Utrecht, Netherlands.
authors.forename: René S
authors.initials: RS
authors.lastname: Kahn
authors.affiliation: 1Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht Utrecht, Netherlands.
authors.forename: Hilleke E
authors.initials: HE
authors.lastname: Hulshoff Pol
keywords: DTI; MRI imaging; activation; task performance and analysis; white matter