Tinnitus Multimodal Imaging
Abstract
Tinnitus is a common auditory perceptual disorder whose neural substrates are under intense debate. This project takes a multimodal imaging approach to dissect its neural circuits. Resting-state functional MRI revealed increased striatal-auditory cortical connectivity was isolated to area LC, positioned at the junction of the head and body of the caudate nucleus, where hyperconnectivity was positively correlated with tinnitus severity. Striatal connectivity was also increased between area LC and dorsal prefrontal cortex, but reduced between area LC and nucleus accumbens of the ventral striatum. Connectivity of primary auditory cortex was increased to regions within the default-mode network. Those findings provide further evidence to support a striatal gating model of tinnitus, where dysfunctionally-permissive area LC enables auditory phantoms to reach perceptual awareness. Magnetoencephalographic resting-state functional connectivity imaging (MEGI) in tinnitus subjects in the alpha-band showed increased medial prefrontal cortical connectivity. MR spectroscopic imaging (MRSI) successfully captured GABA spectroscopic levels in the caudate nucleus and auditory cortices reliably. 7T structural MRI delivered higher resolution of anatomic structures of the basal ganglia and auditory cortex.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2014
- Accession Number
- ADA613544
Entities
People
- Srikantan S. Nagarajan
- Steven W. Cheung
Organizations
- University of California, San Francisco