Description of the ASL sequence A sequence with pseudo-continuous labeling, background suppression and 3D RARE Stack-Of-Spirals readout with optional through-plane acceleration was implemented for this study. At the beginning of the sequence, gradients were rapidly played with alternating polarity to correct for their delay in the spiral trajectories, followed by two preparation TRs, to allow the signal to reach the steady state. A non-accelerated readout was played during the preparation TRs, in order to obtain a fully sampled k-space dataset, used for calibration of the parallel imaging reconstruction kernel, needed to reconstruct the skipped kz partitions in the accelerated images.

Description of study Non-accelerated and accelerated versions of the sequence were compared during the execution of a functional activation paradigm. For each participant, first a high-resolution anatomical T1-weighted image was acquired with a magnetization prepared rapid gradient echo (MPRAGE) sequence. Subjects underwent two perfusion runs, in which functional data were acquired with the non-accelerated and the accelerated version of the sequence, in pseudo-randomized order, during a visual-motor activation paradigm. During each run, 3 resting blocks alternated with 3 task blocks, with each block comprising 8 label-control pairs (72 s and 64 s for the non-accelerated and accelerated sequence versions, respectively). During the resting blocks, subjects were instructed to remain still while looking at a fixation cross. During the task blocks, a flashing checkerboard was displayed and subjects were asked to tap their right-hand fingers while looking at the center of the board. Labeling and PLD times were 1.5 and 1.5 s. In addition, four M0 images with long TR and no magnetization preparation were acquired per perfusion run for CBF quantification purposes.

Comments added by Openfmri Curators

===========================================

General Comments

Defacing

Pydeface was used on all anatomical images to ensure deindentification of subjects. The code can be found at https://github.com/poldracklab/pydeface

Quality Control

Mriqc was run on the dataset. Results are located in derivatives/mriqc. Learn more about it here: https://mriqc.readthedocs.io/en/latest/

Where to discuss the dataset

1) www.openfmri.org/dataset/ds000234/ See the comments section at the bottom of the dataset page. 2) www.neurostars.org Please tag any discussion topics with the tags openfmri and ds000234. 3) Send an email to submissions@openfmri.org. Please include the accession number in your email.

Known Issues

N/A

Bids-validator Output

Description of the ASL sequence A sequence with pseudo-continuous labeling, background suppression and 3D RARE Stack-Of-Spirals readout with optional through-plane acceleration was implemented for this study. At the beginning of the sequence, gradients were rapidly played with alternating polarity to correct for their delay in the spiral trajectories, followed by two preparation TRs, to allow the signal to reach the steady state. A non-accelerated readout was played during the preparation TRs, in order to obtain a fully sampled k-space dataset, used for calibration of the parallel imaging reconstruction kernel, needed to reconstruct the skipped kz partitions in the accelerated images.

Description of study Perfusion data were acquired on an elderly cohort using the single-shot, accelerated sequence. For each participant, first a high-resolution anatomical T1-weighted image was acquired with a magnetization prepared rapid gradient echo (MPRAGE) sequence. Resting perfusion data were acquired with a 1-shot 1D-accelerated readout for a total scan duration of 5 min, with labeling and PLD times of 1.5 and 1.5 s. Two M0 images with long TR and no magnetization preparation were acquired per run for CBF quantification purposes.

Comments added by Openfmri Curators

===========================================

General Comments

Defacing

Pydeface was used on all anatomical images to ensure deindentification of subjects. The code can be found at https://github.com/poldracklab/pydeface

Quality Control

Mriqc was run on the dataset. Results are located in derivatives/mriqc. Learn more about it here: https://mriqc.readthedocs.io/en/latest/

Where to discuss the dataset

1) www.openfmri.org/dataset/ds000236/ See the comments section at the bottom of the dataset page. 2) www.neurostars.org Please tag any discussion topics with the tags openfmri and ds000236. 3) Send an email to submissions@openfmri.org. Please include the accession number in your email.

Known Issues

N/A

Bids-validator Output

1: This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. (code: 1 - NOT_INCLUDED) /sub-01/func/sub-01_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-01_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-02/func/sub-02_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-02_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-03/func/sub-03_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-03_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-04/func/sub-04_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-04_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-05/func/sub-05_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-05_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-06/func/sub-06_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-06_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-07/func/sub-07_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-07_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-08/func/sub-08_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-08_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-09/func/sub-09_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-09_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-10/func/sub-10_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-10_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-11/func/sub-11_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-11_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-12/func/sub-12_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-12_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-13/func/sub-13_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-13_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-14/func/sub-14_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-14_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-15/func/sub-15_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-15_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-16/func/sub-16_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-16_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-17/func/sub-17_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-17_task-rest_acq-1Daccel1shot_asl.nii.gz /sub-18/func/sub-18_task-rest_acq-1Daccel1shot_asl.nii.gz This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: sub-18_task-rest_acq-1Daccel1shot_asl.nii.gz /task-rest_asl.json This file is not part of the BIDS specification, make sure it isn't included in the dataset by accident. Data derivatives (processed data) should be placed in /derivatives folder. Evidence: task-rest_asl.json

  Summary:         Available Tasks:    Available Modalities:
  61 Files, 915.87MB                T1w
  18 - Subjects
  1 - Session

Description of the ASL sequence A sequence with pseudo-continuous labeling, background suppression and 3D RARE Stack-Of-Spirals readout with optional through-plane acceleration was implemented for this study. At the beginning of the sequence, gradients were rapidly played with alternating polarity to correct for their delay in the spiral trajectories, followed by two preparation TRs, to allow the signal to reach the steady state. A non-accelerated readout was played during the preparation TRs, in order to obtain a fully sampled k-space dataset, used for calibration of the parallel imaging reconstruction kernel, needed to reconstruct the skipped kz partitions in the accelerated images.

Description of study Single-shot and two-shot versions of the accelerated sequence were acquired during rest. For each participant, first a high-resolution anatomical T1-weighted image was acquired with a magnetization prepared rapid gradient echo (MPRAGE) sequence. Subjects were instructed to remain still and awake, while resting perfusion data were acquired using either 1-shot or 2-shot 1D-accelerated readout. 64 and 32 label-control images were acquired, respectively, during a total scan time of 5 min. Labeling and PLD times where 1.8 and 1.8 s. Two M0 images with long TR and no magnetization preparation were acquired per run for CBF quantification purposes.

Comments added by Openfmri Curators

===========================================

General Comments

Defacing

Pydeface was used on all anatomical images to ensure deindentification of subjects. The code can be found at https://github.com/poldracklab/pydeface

Quality Control

Mriqc was run on the dataset. Results are located in derivatives/mriqc. Learn more about it here: https://mriqc.readthedocs.io/en/latest/

Where to discuss the dataset

1) www.openfmri.org/dataset/ds000235/ See the comments section at the bottom of the dataset page. 2) www.neurostars.org Please tag any discussion topics with the tags openfmri and ds000235. 3) Send an email to submissions@openfmri.org. Please include the accession number in your email.

Known Issues

N/A

Bids-validator Output