5 Matching Annotations
  1. May 2022
    1. what happens when you see one of these so-called pictures of the brain you've all seen these things they have red and blue and yellow and so on there's no red 00:01:21 and blue and yellow in the brain what happens is this if the pictures are not pictures of the brain they're pictures of gia the ratio of oxygenated to 00:01:35 deoxygenated blood in certain places and when neurons fire they need to be getting some oxygen back in there too so they can fire again and it turns out that they have different magnetic 00:01:49 properties if their oxygen if the blood is oxygenated or not and what you see actually is a bunch of pixels and each little pixel is actually 3 millimeters 00:02:03 by 3 millimeters by 3 millimeters 3 millimeters cubed and it goes over anywhere between one second and several seconds now if you ask how many neurons are in there the answer is about 125 00:02:17 million per pixel each neuron is connected to between a thousand and 10,000 other neurons so there are tens of billions of connections lots of circuitry in that one little 00:02:30 pixel and that picture doesn't show you what's going on in that circuitry very important you know we cannot see that we can say hey something is happening there

      Each pixel is an output from 125 million cells. It's similar to a country that votes for a president or prime minister. If you try to figure out how that leader was voted into power without analyzing all the voters, that is quite an impossible task!

  2. Jan 2022
    1. Douaud, G., Lee, S., Alfaro-Almagro, F., Arthofer, C., Wang, C., McCarthy, P., Lange, F., Andersson, J. L. R., Griffanti, L., Duff, E., Jbabdi, S., Taschler, B., Winkler, A. M., Nichols, T. E., Collins, R., Matthews, P. M., Allen, N., Miller, K. L., & Smith, S. M. (2021). Brain imaging before and after COVID-19 in UK Biobank (p. 2021.06.11.21258690). https://doi.org/10.1101/2021.06.11.21258690

  3. Nov 2021
    1. (the VTA is also part ofthis system, but is too small to image with standard fMRImethods, but see [35] for successful imaging methods).

      All imaging studies face questions of validity and should (and many do) link to comprehensive details on instrumentation, methodology, and interpretation. Apparently, the professional consensus remains that, properly executed and interpreted, fMRI and other functional imaging techniques based on detection of oxygenation can lead to highly valid conclusions. (See Nautil.us article.)

    2. imaging the brain of an individual who claims to generatejoy without any external rewards or cues could point the waytoward improved training in joy and greater resilience in theface of external difficulties. Of particular interest is the neuralmechanisms by which happiness is generated.

      Such a self-administered neural 'technology' of happiness should be driving much more related research but I see no other neuroscientific studies delving into jhanas.

    3. We report the first neural recording during ecstatic meditations called jhanas and test whether a brain reward system plays a rolein the joy reported. Jhanas are Altered States of Consciousness (ASC) that imply major brain changes based on subjective reports:(1) external awareness dims, (2) internal verbalizations fade, (3) the sense of personal boundaries is altered, (4) attention is highlyfocused on the object of meditation, and (5) joy increases to high levels. The fMRI and EEG results from an experienced meditatorshow changes in brain activity in 11 regions shown to be associated with the subjective reports, and these changes occur promptlyafter jhana is entered. In particular, the extreme joy is associated not only with activation of cortical processes but also with activationof the nucleus accumbens (NAc) in the dopamine/opioid reward system. We test three mechanisms by which the subject mightstimulate his own reward system by external means and reject all three. Taken together, these results demonstrate an apparentlynovel method of self-stimulating a brain reward system using only internal mental processes in a highly trained subject.

      I can find no other research on this particular matter. It would be helpful to have other studies to validate or invalidate this one. This method of reward requires a highly-trained participant and involves no external means.