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echo_time

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This is fantastic - but I encountered something strange. I was searching `ghostty per window shader` and your site came up as the first hit. Excellent - however, this was the text under the link:

Fun with Ghostty Shaders 22 Feb 2025 — Ghostty doesn't directly support shaders, but a repo with shaders can be cloned to ~/.config/ghostty/shaders. Examples include 'drunkard+retro- ...

Now, no where in the text on the site does it say this - so did google just wrongly summarize and put it in as "website text". To be clear, this isn't an AI overview - its in the main list of links! Maybe this has been happening and i just missed it but its absurd! It doesn't even fit with the text! Thanks for the resource, again, had a lot of fun with that.

This looks incredible, and its obvious that a lot of work has been done, but in exploring it I notice a lot of things that make me hesitate to spend the money!

First, in the section "Expressions are flashcards on steroids", the flavor text on each element (Translations, Audio, etc) is identical.

Next, I look at the pricing and get one idea. Then when I create an account and go to upgrade, I see completely different pricing options. Its not that I care so much about the options, but it kind of worries me!

At one point I swear I saw the phrase "Say something about comprehensible input" instead of an explanation of CI, and the sentence itself was duplicated but now I don't. Maybe you are making this landing page live? It _is_ a nice landing page, to be sure.

Overall, I think it looks really cool and I'm interested in trying it out but just a little nervous at the moment.

Note for Firefox users - view the page in Chrome to see more of what they are talking about. I was very confused by some of the images, and it was a world of difference when I tried again in Chrome. Things began to make a lot more sense - is there a flag I am missing in Firefox on the Mac?

In some ways, absolutely not - precision is a huge challenge with an indirect method like fMRI - but this example is over a decade old now: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3130346/

Fig4 shows the letter M on the cortical surface, where the stimulus accounted for the effects of foveal magnification (foveal vision gets more cortical space). Keep in mind that we now, in theory, have stronger magnets, better head coils (the part that picks up the image information), and better sequences (the software that manipulates the magnets to produce the images) so we could do even better than that these days.

If the images are in DICOM format, which is common, then dcm2niix should be able to convert them https://github.com/rordenlab/dcm2niix

I think it can handle a few other formats as well. Once they are .nii(.gz) files, then mricrogl (https://www.nitrc.org/projects/mricrogl) should be able to render it - of course, for a brain scan - this would be your whole head. Brain extraction is performed by more specialized software, but that would get you started.

They are human size research (and now clinical, albeit limited so far) magnets, so big enough, think about 60cm. It's an elbow rubbing environment, but sufficient for even somewhat large adults. The animals magnets are super tiny, of course.

Clinical scanners often use 2mm isotropic voxels, or even 3. Clinical usage is almost a bad reference point!. Research MRI at ultra high field (7T) goes to 0.8mm isotropic and below (0.5 or 0.6 is possible).

7T is already regularly used for human research, and approval for human usage has been granted for 10.5T and I believe for 11.7T (though I'm not sure how many images they've gotten out of that yet).

Yes it is incredibly expensive, but it is in fact already done.

This is incorrect - all of the protons align along the static (the strong 1.5, 3 , 9.4 etc Tesla) field, some point one way, and some the other - but they have all shifted so that they line up. The excite portion is a separate step, distinct from the static (B0) field. edit: distinct in some ways - the strength of the static field determines the RF used to flip the protons out of alignment.