Poster C119, Sunday, March 26, 5:00 – 7:00 pm, Pacific Concourse
Functional parcellation of the planum temporale
Alex Teghipco1, Prantik Kundu2,3, Bradley R. Buchsbaum4, Peter A. Bandettini5, Gregory Hickok1; 1University of California, Irvine, 2Icahn School of Medicine at Mt. Sinai, 3University of Cambridge, 4University of Toronto, 5National Institute of Mental Health
The planum temporale (PT) is classically linked to language but has been shown to play a role in a wide range of auditory, speech, and sensorimotor function. Evidence from cytoarchitectonics supports the presence of several subregions within PT and fMRI has demonstrated broad functional-anatomical parcellations along a handful of dimensions including sensory-motor versus spatial processing, speech perception versus production, and spatial versus non-speech auditory processing. Here we use a multivariate approach to functionally parcellate the PT using activation patterns reported in over 10,000 published articles in the Neurosynth database and independently validate the parcellation in a group of 136 participants who performed resting state fMRI. Voxels within a meta-analytically defined functional PT region were clustered based on the likelihood that they coactivated with similar regions of the brain. Clustering was carried out using k-means and an optimal solution was determined, revealing an organization of 9 anatomically segregable clusters. Analysis of cluster similarity on the basis of both resting functional connectivity and coactivation indicated the presence of two supraordinate clusters in PT. Nonparametric tests displayed subtle differences between clusters but highlighted a consistent pattern whereby dorsal clusters of the PT were more connected and coactivated with premotor, motor, and sensorimotor regions. In contrast ventral clusters showed a stronger relationship to the superior and middle temporal gyri, as well as the inferior and superior frontal gyri. These methods shed new light on functional organization within the PT, indicating a constellation of subfields that are broadly organized into dorsal and ventral streams.
Topic Area: PERCEPTION & ACTION: Other