MP2RAGE: challenges and artifacts of its use for layer-fMRI

The MP2RAGE sequence is very popular for 7T anatomical imaging and is very commonly used to acquire 0.7-1 mm resolution whole brain anatomical reference data. Aside of this common application, it can also be very helpful for layer-fMRI studies to obtain even higher resolution T1 maps in the range of 0.5mm iso. However, when optimizing MP2RAGE sequence parameters for layer-fMRI studies, there are a few things that might be helpful to keep in mind.

In this post, I would like to discuss the challenges of using the popular MP2RAGE sequence in layer-fMRI studies. Specifically I will discuss challenges/features regarding:

Continue reading “MP2RAGE: challenges and artifacts of its use for layer-fMRI” →

Example analysis pipeline of layer-VASO

In this blog post I want to go through the analysis pipeline of layer-dependent VASO.

I will go through the all the analysis steps that need to be done to go from raw data from the scanner to final layer profiles. The entire thing will take about 30 min (10 min analysis and 20 min explaining and browsing through data).

During the entire analysis pipeline I am using the following software packages: SPM, AFNI, and LAYNII, and gnuplot (if you want fancier plotting tools)

Continue reading “Example analysis pipeline of layer-VASO” →

How many layers should I extract?

In this blog post, I want to share my thoughts on the number of layers that should be extracted from any given dataset. I will try to give an overview of how many layers are usually extracted in the field, I’ll describe my personal choices of layer numbers, and I will try to discuss the challenges of layer signal extraction along the way.

Continue reading “How many layers should I extract?” →

‘layer fMRI’, ‘sub-millimeter fMRI’, ‘mesoscopic fMRI’, or ‘cortical depth dependent fMRI’…. Which term should I use?

What’s the best name of our field and what’s the best attributing term for our data? There are many competing options: “Layer fMRI”, “mesoscopic fMRI”, “sub-millimeter fMRI”, “ultra-high resolution fMRI”, “laminar fMRI”, “cortical depth-dependent fMRI”. They differ with respect to how flashy they are, how scientifically appropriate they are, and how popular they are.

In this blog post, I want to review which ones are the most popular ones in the field and also share some thoughts on my favourite candidates.

Edits on March 3rd 2019 with contributions and clarifications taken from Kamil Uludağ, Sri Kashyap and  Faruk Gulban.

Continue reading “‘layer fMRI’, ‘sub-millimeter fMRI’, ‘mesoscopic fMRI’, or ‘cortical depth dependent fMRI’…. Which term should I use?” →

Registration of high-resolution data

In this blog post Sri Kashyap and I describe how to deal with the registration of high-resolution datasets across days, across different resolutions, and across different sequences.

I am particularly fond of the following two tools: Firstly, ITK-SNAP for visually-guided manual alignment and secondly, using ANTs programs: antsRegistration and antsApplyTransforms.

Continue reading “Registration of high-resolution data” →