Using Structural and Functional Brain Imaging to Investigate Responses to Acute Thermal Pain.
Despite a fundamental interest in the relationship between structure and function, the relationships between measures of white matter microstructural coherence and functional brain responses to pain are poorly understood. We investigated whether fractional anisotropy (FA) in 2 white matter regions in pathways associated with pain is related to the functional magnetic resonance imaging (fMRI) blood oxygen level-dependent (BOLD) response to thermal stimulation. BOLD fMRI was measured from 16 healthy male subjects during painful thermal stimulation of the right arm. Diffusion-weighted images were acquired for each subject and FA estimates were extracted from the posterior internal capsule and the cingulum (cingulate gyrus). These values were then included as covariates in the fMRI data analysis. We found BOLD response in the midcingulate cortex (MCC) to be positively related to FA in the posterior internal capsule and negatively related to FA in the cingulum. Our results suggest that the MCC's involvement in processing pain can be further delineated by considering how the magnitude of the BOLD response is related to white matter microstructural coherence and to subjective perception of pain. Considering relationships to white matter microstructural coherence in tracts involved in transmitting information to different parts of the pain network can help interpretation of MCC BOLD activation.



Relationships between functional brain responses, white matter microstructural coherence, and subjective ratings are crucial for understanding the role of the MCC in pain. These findings provide a basis for investigating the effect of the reduced white matter microstructural coherence observed in some pain disorders on the functional responses to pain.
Institute of Neuroscience and Medicine, Jülich, Germany. Electronic address: t.warbrick@fz-juelich.de.
Tracy
T
Warbrick
Institute of Neuroscience and Medicine, Jülich, Germany.
Vera
V
Fegers-Stollenwerk
Institute of Neuroscience and Medicine, Jülich, Germany.
Ivan I
II
Maximov
Institute of Neuroscience and Medicine, Jülich, Germany; Department of Neurology, Faculty of Medicine, RWTH Aachen University, Aachen, Germany.
Farida
F
Grinberg
Institute of Neuroscience and Medicine, Jülich, Germany; Department of Neurology, Faculty of Medicine, RWTH Aachen University, Aachen, Germany; Jülich Aachen Research Alliance (JARA) - Translational Brain Medicine, Aachen and Jülich, Germany.
N Jon
NJ
Shah
D000328:Adult; D016880:Anisotropy; D001921:Brain / Q000000981:diagnostic imaging* / Q000473:pathology; D001931:Brain Mapping; D038524:Diffusion Magnetic Resonance Imaging; D006801:Humans; D006930:Hyperalgesia / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology*; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D010100:Oxygen / Q000097:blood; D010147:Pain Measurement; D013696:Temperature; D066127:White Matter / Q000000981:diagnostic imaging*; D055815:Young Adult
D010100:Oxygen
Acute pain; diffusion tensor imaging; fractional anisotropy; functional magnetic resonance imaging; multimodal imaging