# QUANTUM_4S: 7T fMRI of context inference in a hierarchical decision task

## Overview
Fourteen healthy adults (10 female, aged 20-33 years) performed a hierarchical decision-making task across four fMRI sessions on different days. On each trial, a cloud of colored moving dots (cue) indicated which of two categorization subtasks to perform on a composite face/scene image (probe): face (male vs. female) or scene (city vs. landscape). The mapping between cue attributes (red, yellow, left, right) and subtasks defined four latent task contexts, two based on color and two based on motion. The context changed covertly every 10-20 trials and had to be inferred from feedback. Subjects reported both the subtask answer and the cue attribute they used, so their believed context could be identified on every trial. Color and motion coherence of the cue were varied independently across trials.

## Dataset structure
- 14 subjects, 4 sessions each (`ses-1` to `ses-4`, numbered in chronological order)
- per session: 5 runs of the task (`task-Quantum4S`, 40 trials and 430 volumes per run) and one T1-weighted anatomical image

## Acquisition
GE SIGNA 7T, Magnetic Resonance Research Facility, University of Iowa.
- Functional: multiband EPI (factor 2), TR = 1712 ms, TE = 20.5 ms, flip angle 60 deg, FoV 220 mm, 2 x 2 x 2 mm voxels, 68 transverse slices
- Anatomical: MPRAGE, TR = 3600 ms, TE = 3 ms, flip angle 8 deg, FoV 220 mm, 0.70 x 0.43 x 0.43 mm voxels, 220 sagittal slices

Anatomical images are defaced.

## Ethics
The study was approved by the University of Iowa Institutional Review Board (IRB No. 202207126). All participants gave written informed consent, including consent for data sharing.