Large Single-Subject Functional MRI Datasets at 7T

# Overview

## Subjects
Three subjects with no known history of neurological disorders (2 females; age=25±2.5 years) completed this study. All participants gave informed consent in compliance with a protocol approved by the Institutional Review Board of the National Institute of Mental Health in Bethesda, MD, USA.

## Experimental Tasks
All functional runs had the same organization of blocks. An initial 10-s rest period was followed by 5 repetitions of a 20-s task block and a 40-s rest block. An additional 10 s of rest were added at the end of each func- tional run, resulting in 320 s runs. During the rest periods, subjects were instructed to remain still and focus their attention on a black fixation crosshair over a gray background. Note that the paradigm from our prior study at 3T had an additional 20 s of rest at the beginning of each run and used a white fixation cross on a black background. During the task epochs, each subject did 1 of 3 different tasks described below. Each subject always performed the same task across all 100 runs.
1. Full Field-of-View Visual Stimulation + Attention Control Task ( fFOV + Task): The subject was instructed to focus his/her attention on a crosshair at the center of a full FOV flickering checkerboard (frequency = 8 Hz) and to perform a letter/number discrimination task. Four random alphanumeric characters appeared for 400 ms at random intervals in the center of the flickering checkerboard during each block. The subject was provided with a four-button re- sponse box in his/her right hand and was instructed to press one button if the character on the screen was a letter and another button if it was a number (same as in Gonzalez-Castillo et al. (2012)).
2. Full Field-of-View Visual Stimulation Only (fFOV Only): The subject was instructed to focus his/her attention on a crosshair in the center of a full FOV flickering checkerboard (frequency = 8 Hz). No letter/number discrimination task was present.
3. Hemifield Visual Stimulation (hFOV Only): The subject was in- structed to focus his/her attention on a crosshair in the center of a left hemifield flickering checkerboard (frequency = 8 Hz; degrees left of center = 3). No letter/number discrimination task was present.

## Data Acquisition
Imaging was performed on a Siemens 7T MRI scanner equipped with a 32-element receive coil (Nova Medical, Wilmington, MA, USA). Function- al runs were obtained using a gradient-recalled, single-shot, echo-planar imaging (EPI) sequence (TR = 2.0 s, TE = 25 ms, FA = 50°, 54 oblique slices, slice thickness = 2 mm, spacing = 0 mm, in-plane resolution = 2 × 2 mm, FOV = 192 mm, acceleration factor (GRAPPA) = 2). T1-weighted magnetization-prepared rapid gradient-echo data were also acquired for presentation and alignment purposes (sagittal prescription, number of slices per slab = 192, slice thickness = 1 mm, square FOV = 256 mm)