Computational Neuroanatomy - Science topic

I need a standard brain connectivity matrix (CM) for healthy and pathological conditions, such as Alzheimer's disease, Down syndrom, etc. namely, a text or binary file which has all the connection strengths between some regions of interest (ROIs). I need this matrix, in addition to the MNI map of the ROIs used in the matrix. I couldn't find any database for it. It seems that each group measures these matrices by their own, rather than referring to a general database.

Is there a general database for brain connectivity that anyone can use and refer to? A matrix for the connections and physical locations of the default mode network (DMN) would also help.

Thanks in advance for your help!

In sleep, brain activity, specially in the default mode network (DMN) is reduced. For example, Amyloid beta production by neurons has a 70 % jump in wakefulness compared with sleep (Kress et al. 2018 J Exper Med). Can one assume that the same would happen in case of coma, or anaesthesia? Are they similar at all in terms of brain activity?

As I searched, it seems we are able to induce an artificial coma, like what we do for anaesthesia? If so, how long could it last at most?

The last but not least, have people taken effect systematic MRI during comma, anaesthesia, and sleep?

I thank you in advance for your help.

Hi everyone. I am currently investigating data on cerebral blood flow in an aging population of Alzheimer's disease (MCI, demented) and matched controls. My method is Arterial Spin Labeling (ASL-MRI). Does anyone have experience, whether the correction for partial volume effects (PVE) should be used in addition (!) with atrophy rates from a VBM analysis as a covariate in group comparisons? Or will this "over-correct" the results? I will compare the diagnostic groups, as well as different imaging modalities. Thank you in advance.

I want to study aneurysm growth (in volume) in a set of subjects, based on Time of Flight images (MR) images at two time points.

For each subject, I want to do a rigid registration between time of flight images as well as a segmentation of the cerebral vascular system. And then, I want to compare the two registered segmentation volumes in order to quantify the aneurysm growth.

For doing this, some teams used in-house registration tools (not distributed as far as I know, AnToNIA for ex) and the registration is performed using a volume of interest around the aneurysm sac (and not using the whole brain).

I currently know free registration tools not specific to aneurysms (FLIRT of FSL for exemple: http://fsl.fmrib.ox.ac.uk/fsl/fslwiki/FLIRT). Additional question: Do you think these kind of methods is appropriate to do "aneurysms registration" ? 

Thanks in advance,

Hi all ! I have 100 patients with a pASL sequence and would like to get some information about the CBF. Is this actually possible with just one TI ? Can I somehow calculate an arterial transit time ? Because if I just measure at one time-point, I do not know whether the bolus has already passed or not arrived yet, right ? Is it only useful for grey matter or also white matter ?

Thanks for any help !

We need to evaluate the density of neurons per volume in different brain nuclei. We have serial sections of brain tissue and want to perform dissector counting method. Any cues?