Live data from Hacker News

Deep image reconstruction from human brain activity (2017)

biorxiv.org

21–30 of 97 posts

Re: Deep image reconstruction from human brain activity (2017)

#23

Acknowledging that I know nothing about psychology or neuroscience... It's interesting that they were not able to extract good images from the test when they just asked the subjects to imagine the pictures. I speculate that is because the vast majority of people are able to recognize images of things, but not produce those images. For a simple example, see this article about people trying to draw a bicycle. Before cl…

there is also evidence this ability to conjure imagery in our minds simply does not exist for some: https://en.wikipedia.org/wiki/Aphantasia

which leads me to wonder if the capability exists on a spectrum and is stronger or weaker in some. A stronger capability might correlate to a stronger 'signal' ...?

Re: Deep image reconstruction from human brain activity (2017)

#24
post #23

Acknowledging that I know nothing about psychology or neuroscience... It's interesting that they were not able to extract good images from the test when they just asked the subjects to imagine the pictures. I speculate that is because the vast majority of people are able to recognize images of things, but not produce those images. For a simple example, see this article about people trying to draw a bicycle. Before cl…

there is also evidence this ability to conjure imagery in our minds simply does not exist for some: https://en.wikipedia.org/wiki/Aphantasia which leads me to wonder if the capability exists on a spectrum and is stronger or weaker in some. A stronger capability might correlate to a stronger 'signal' ...?

[deleted]

Re: Deep image reconstruction from human brain activity (2017)

#25

Acknowledging that I know nothing about psychology or neuroscience... It's interesting that they were not able to extract good images from the test when they just asked the subjects to imagine the pictures. I speculate that is because the vast majority of people are able to recognize images of things, but not produce those images. For a simple example, see this article about people trying to draw a bicycle. Before cl…

I think what's maybe misleading here is that while there may be an accurate representation of a bicycle somewhere in someone's brain, that does not mean they're able to consciously access it and, e.g., recreate it through a task of complex motor coordination etc. (in order to produce a drawing, I mean).

However, if you are using an fMRI, as in the paper, all you need is the accurate representation somewhere (and you need to know where that somewhere is of course).

Another example: let's say you look at a picture of cheetah. Now you try to imagine it; what appears to you is a vague sort of resemblance but nowhere near as clear as when you were looking directly at it. But, just because the prompting for you to imagine the image didn't cause an accurate recreation in consciousness, doesn't mean it didn't occur elsewhere, perhaps at some earlier/lower-level stage of visual processing.

Re: Deep image reconstruction from human brain activity (2017)

#26
post #13

When we build neural networks to decode our own neural networks...

neuroscientists have been using "ai" for basically ever. except to them it's not "ai," it's just mathematical tools for data analysis.

Never mentioned AI. Simply noting that the mathematical tool used here is inspired by the brain.

Re: Deep image reconstruction from human brain activity (2017)

#27

Acknowledging that I know nothing about psychology or neuroscience... It's interesting that they were not able to extract good images from the test when they just asked the subjects to imagine the pictures. I speculate that is because the vast majority of people are able to recognize images of things, but not produce those images. For a simple example, see this article about people trying to draw a bicycle. Before cl…

I think what's maybe misleading here is that while there may be an accurate representation of a bicycle somewhere in someone's brain, that does not mean they're able to consciously access it and, e.g., recreate it through a task of complex motor coordination etc. (in order to produce a drawing, I mean). However, if you are using an fMRI, as in the paper, all you need is the accurate representation somewhere (and you…

I don't think the "draw a bicycle" task involves complex motor coordination. It's drawing 2 circles and ~10 straight lines. Doesn't need to be photorealistic, just in the correct configuration.

For example, I cannot visualize a 13-sided polygon accurately, but I can draw one pretty easily without having any drawing skills.

Re: Deep image reconstruction from human brain activity (2017)

#28

When we build neural networks to decode our own neural networks...

Do you remember that project that mapped where words are "stored" in the brain? I don't have it right now, but it was something like that. They used a neural approach to map the word vectors in the brain.

Re: Deep image reconstruction from human brain activity (2017)

#30
This looks awesome, but the methodology and experimental setup look pretty complicated and just on that basis alone it seems like there'd be some risk of bias or overfitting to creep into the analysis... I'm not criticizing the researchers or the experimental design, it's just a danger in any complicated study like this.

Bottom line, I'm definitely interested in this paper, but want to wait and see if others can replicate the results before getting overly excited.

Post reply on HN