We present an ultra-high resolution MRI dataset of an ex vivo human brain specimen. The brain specimen was donated by a 58-year-old woman who had no history of neurological disease and died of non-neurological causes. After fixation in 10% formalin, the specimen was imaged on a 7 Tesla MRI scanner at 100 µm isotropic resolution using a custom-built 31-channel receive array coil. Single-echo multi-flip Fast Low-Angle SHot (FLASH) data were acquired over 100 hours of scan time (25 hours per flip angle), allowing derivation of synthesized FLASH volumes. This dataset provides an unprecedented view of the three-dimensional neuroanatomy of the human brain. To optimize the utility of this resource, we warped the dataset into standard stereotactic space. We now distribute the dataset in both native space and stereotactic space to the academic community via multiple platforms. We envision that this dataset will have a broad range of investigational, educational, and clinical applications that will advance understanding of human brain anatomy in health and disease.

1We present an ultra-high resolution MRI dataset of an ex vivo human brain 2 2 specimen. The brain specimen was donated by a 58-year-old woman who 2 3 had no history of neurological disease and died of non-neurological causes. 4After fixation in 10% formalin, the specimen was imaged on a 7 Tesla MRI 2 5 scanner at 100 µm isotropic resolution using a custom-built 31-channel 2 6 receive array coil. Single-echo multi-flip Fast Low-Angle SHot (FLASH) data 2 7 were acquired over 100 hours of scan time (25 hours per flip angle), allowing 2 8 derivation of a T1 parameter map and synthesized FLASH volumes. This 2 9dataset provides an unprecedented view of the three-dimensional 3 0 neuroanatomy of the human brain. To optimize the utility of this resource, we 3 1 warped the dataset into standard stereotactic space. We now distribute the 3 2 dataset in both native space and stereotactic space to the academic 3 3 community via multiple platforms. We envision that this dataset will have a 3 4 broad range of investigational, educational, and clinical applications that will 3 5 advance understanding of human brain anatomy in health and disease. 3 6 3 7 Design Type(s) Single measure design Measurement Type(s) Nuclear magnetic resonance assay Technology Type(s) 7 Tesla MRI scanner Factor Type(s) Sample Characteristic(s) Homo sapiens • brain 3 8 3 Background & Summary 3 9 Postmortem ex vivo MRI provides significant advantages over in vivo MRI for 4 0 visualizing the microstructural neuroanatomy of the human brain. Whereas in 4 1 vivo MRI acquisitions are constrained by time (i.e. ~hours) and affected by 4 2 motion, ex vivo MRI can be performed without time constraints (i.e. ~days) 4 3 and without cardiorespiratory or head motion. The resultant advantages for 4 4 characterizing neuroanatomy at microscale are particularly important for 4 5 identifying cortical layers and subcortical nuclei 1-5 , which are difficult to 4 6 visualize even in the highest-resolution in vivo MRI datasets 6,7 . Ex vivo MRI 4 7 also provides advantages over histological methods that are associated with 4 8distortion and tearing of human brain tissue during fixation, embedding, and 4 9

Summary Prior research using functional magnetic resonance imaging (fMRI) [1–4] and behavioral studies of patients with acquired or congenital amusia [5–8] suggest that the right posterior superior temporal gyrus (STG) in the human brain is specialized for aspects of music processing (for review see 9–12). Intracranial electrical brain stimulation in awake neurosurgery patients is a powerful means to determine the computations supported by specific brain regions and networks [13–21], because it provides reversible causal evidence with high spatial resolution (for review, see [22, 23]). Prior intracranial stimulation or cortical cooling studies have investigated musical abilities related to reading music scores [13, 14] and singing familiar songs [24, 25]. However, individuals with amusia (congenitally, or from a brain injury) have difficulty humming melodies but can be spared for singing familiar songs with familiar lyrics [26]. Here we report a detailed study of a musician with a low-grade tumor in the right temporal lobe. Functional MRI was used pre-operatively to localize music processing to the right STG, and the patient subsequently underwent awake intraoperative mapping using direct electrical stimulation during a melody repetition task. Stimulation of the right STG induced ‘music arrest’ and errors in pitch, but did not affect language processing. These findings provide causal evidence for the functional segregation of music and language processing in the human brain, and confirm a specific role of the right STG in melody processing.