Is the colour you see the same as what I see? It’s a question that has puzzled both philosophers and neuroscientists for decades, but has proved notoriously difficult to answer… Now, a study that recorded patterns of brain activity in 15 participants suggests that colours are represented and processed in the same way in the brains of different people.

The researchers found that in most cases they were able to predict which colour was being viewed by a participant in this second group, using the patterns of brain activity they had seen in the first group. They also found that different colours were processed by subtly different areas within the same region of the visual cortex, and that different brain cells responded more strongly to particular colours. These differences were consistent across participants.

The paper on Journal of Neuroscience (sadly not open access): https://www.jneurosci.org/content/early/2025/08/29/JNEUROSCI.2717-20.2025


My critique is… the researchers are based in Tubingen, Germany, and I assume most of their 15 participants are of European cultural heritage (cannot verify… no open access). I would love to see if they can replicate this in a more multi-cultured setting. Some Asian cultures have rather different verbiage for different colors, and I wonder whether that would bias ppl’s perception.

  • MrEff@lemmy.world
    link
    fedilink
    English
    arrow-up
    8
    ·
    edit-2
    15 hours ago

    Participants 120 We analyzed fMRI data from N = 15 (2 male, 13 female) participants aged between 22 and 35 121 years (mean: 25.5) who took part in a previously published fMRI study about color vision 122 (Bannert & Bartels, 2018). The participants were the subset from the prior study for whom the 123 cortical retinotopic representations of the visual field were measured along both the polar and 124 the eccentricity axis of the visual field. All participants had normal or corrected-to-normal visual 125 acuity and were tested for normal color vision using Ishihara color plates (Ishihara, 2011). Each 126 participant gave written informed consent before the first study session. The experiment was 127 approved by the local ethics committee of the Tübingen University Hospital.

    Ignore the numbers 120-127, those are line numbers.

    Doesn’t say. To be fair, you normally aren’t allowed to collect biographical data or any additional identifying data without a specific purpose tied directly to your research question. If they wanted to answer your question they would have to redo the study under a different IRB application. Interesting question, but I would guess you wouldn’t see a difference in an fmri. The voxel sizes for functional are normally 2mm while what you are eluding to is the difference of a few thousand neurons wired a little differently. That difference would be extremely difficult to detect with 2mm voxels. Even at 1mm it would be difficult. When it comes to brain structures there really aren’t significant different between races or cultures more than the variance that already exists between people.

    • zlatiah@lemmy.worldOP
      link
      fedilink
      English
      arrow-up
      1
      ·
      11 hours ago

      That checks out, thanks for pointing this out. I’m much more familiar with clinical trials where ppl’s race/ethnicity do play an importance (and is also a hot topic for debate… from both sides of the political spectrum), hence I was a bit surprised they didn’t include it. If there really is no significant cultural differences that would be amazing

      Also one can dream they get 120+ participants for scanning

      • MrEff@lemmy.world
        link
        fedilink
        English
        arrow-up
        2
        ·
        5 hours ago

        N=15 is a normal size on FMRI studies. It is about the smallest size you can have and still make your significance cut offs while still detecting decently small effects. The time and cost is so much higher than other studies. Some of the bigger FMRI studies start to reach 30-40 ppl. Getting into clinical trial sizes of subjects is unheard of.

        The other thing with FMRI studies that most everyone doesn’t understand is that they aren’t actually looking at activity. They are looking at the BOLD response (blood oxygen level dependance) and that is then correlated to activity. Meaning You can only see blood oxygen uptake. You are not seeing neuron firing, just the metabolic side effect of oxygen use after increased neuron use. This is why you will never be able to see something like a “thought process”. You can only track structures/locations used.

        At the same time we know that no two brains are wired the same even for the smallest of tasks, but they will “structure” their wiring the same. There have been literally hundreds of studies that indirectly see that. Soeach other. Plot out cultural differences versus individual differences would be basically two variance plots on top of eachother.