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Re:Deep image reconstruction from human brain activity (2017) by gamegoblin on Tuesday September 11, 2018 @10:07PM (#17965063)
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 clicking, try to draw a 2D representation of a bicycle -- the wheels, the frame, pedals, handlebars, etc. You'd be surprised how difficult it is. https://road.cc/content/blog/90885-science-cycology-can-you-...

I would be very interested to see them repeat the experiment on e.g. artists who specialize in photorealism, or asking an expert on a very particular thing to imagine that particular thing (e.g. ask a violinist to imagine a violin). I wonder if that would yield more recognizable results than asking a random grad student to visualize a lion's face.

Re:Deep image reconstruction from human brain activity (2017) by westoncb on Tuesday September 11, 2018 @10:43PM (#17965225)
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) by gamegoblin on Tuesday September 11, 2018 @10:57PM (#17965274)
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) by westoncb on Tuesday September 11, 2018 @11:30PM (#17965367)
True. I hesitated to use that as an example because of the potential for confusion—but to clarify, I just meant that the motor skills are an example of another thing being involved beyond a clear representation somewhere, not that they are actually the limiting factor for reproducing the drawing.

A more realistic problem in the case of the bicycle drawing has to do with the procedural knowledge they use for drawing. For instance, maybe they approach it analytically, top-down, breaking it into major components to draw first, and those into sub components. Well, in order to do that, they need explicit knowledge of that hierarchy; they may have an accurate representation of the image somewhere, but they can't bring it directly into consciousness, and they didn't break it into that hierarchy while they had it around. So now what's left to them is to attempt to produce the hierarchy from an imperfectly recalled image, which leads to the strange configurations.

Just a guess—but I wouldn't be surprised to learn it's something on those lines.

Re:Deep image reconstruction from human brain activity (2017) by stuntmachine on Wednesday September 12, 2018 @09:48AM (#17968701)
Re:Deep image reconstruction from human brain activity (2017) by lsh on Tuesday September 11, 2018 @10:32PM (#17965163)
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) by dcw303 on Wednesday September 12, 2018 @12:59AM (#17965679)
I am highly skeptical of Aphantasia, as it's impossible to evaluate what someone else believes they see. I think it's much more likely that Aphantasia is people (like me) who make sharp distinctions between what they can imagine (rotating colors on shapes etc etc) and what they see when looking at something for real - e.g - the detail of a loved one's face.

I challenge anyone who believes they have a highly developed mind's eye to draw such a face purely from memory.

Re:Deep image reconstruction from human brain activity (2017) by jonplackett on Wednesday September 12, 2018 @04:15AM (#17966448)
I have this! I found out from a random daytime TV program and did some online tests. I didn’t realise until that point that other people can make clear images of things in their head.

Weirdly I’m actually quite good at drawing something from memory like a bicycle (I love Pictionary!) but I can’t actually make a image of it in my head.

Brains are strange.

Re:Deep image reconstruction from human brain activity (2017) by kuroguro on Wednesday September 12, 2018 @05:41AM (#17966877)
Agreed, from the description it sounds closer to "people who are aware of the missing parts in the imagined image".

Never heard of this "condition" before. It may apply to me. I can somewhat imagine a static thing or a face but trying to "zoom in"/"rotate" or imagining smaller details completely ruins the illusion.

Re:Deep image reconstruction from human brain activity (2017) by miguelrochefort on Tuesday September 11, 2018 @11:48PM (#17965413)
Do people actually see images of things in their head?

I can close my eyes and think of something, but I won't perceive anything more than a linear description of it.

At best, I can use these visual descriptions to draw an outline in my head, but it instantly fades out if I don't continuously re-draw it.

Kind of like this: https://i.imgur.com/0zuPIPV.gifv

Re:Deep image reconstruction from human brain activity (2017) by selestify on Wednesday September 12, 2018 @12:19AM (#17965521)
Can't reply to your other comment, presumably due to comment depth -- but yes, I did all of those vividly and with ease, even with my eyes open, except for counting the number of icons in my imagined phone screen. Somehow I can imagine the phone screen as a whole, filled with icons, but actually counting them feels weird, like how reading written text inside a dream is weird.

Until I read [0], I had never thought about it and just assumed that everything else was like me. Hah!

[0] https://www.lesswrong.com/posts/baTWMegR42PAsH9qJ/generalizi...

Re:Deep image reconstruction from human brain activity (2017) by ghkbrew on Wednesday September 12, 2018 @12:08AM (#17965487)
Supposedly, most people do. There was an article on hn about "aphantasia" (the lack of mental imagery) not to long ago, but I can't seem to find it now. Google turns up quite a few hits though.

I can't help but be a little sceptical of the concept though. I believe there's probably a spectrum but maybe not as wide is claimed. Based on the comment sections of basically any article on the subect, I wonder if there isn't something like imposter syndrome going on. Where the majority of people dont think they have as sharp mental imagery as the average person.

Re:Deep image reconstruction from human brain activity (2017) by Henk0 on Wednesday September 12, 2018 @12:51AM (#17965638)
Aphantasia is definitely real. My inner visual world has always consisted of the view of the inside of my eyelids. Thinking for me is an almost purely verbal process, in an inner voice that I don’t percieve as sound in any way. I can navigate in my mind, and describe accurately places I’ve been, but there’s never an image, only a kind of spatial perception, combined with knowledge (of materials, colors etc.)

I thought this was how everyone’s mind worked, until I met my ex, who is on the opposite end of the scale. She described her inner world as sometimes more vivid and detailed than the real world. I thought she was almost unique in this, until I started asking other people and realised that most people see images in their mind, of varying detail and vividness. Some can easily project onto their visual input and, for example, put a moustache or wings on someone. I’ve also come to learn that many people hear their own voice when they think (and many, non-schizophrenic, people hear other voices too), and can also imagine smells and tastes.

My episodic memory is affected by my aphantasia, as well as my people recognition skills. I can find it hard to recognise someone if they’ve changed their hair, grown a beard or changed their appearance in some other way.

I do dream though, vivid dreams, and am quite good at recalling them. But again the memory of the dreams, like other memories, is not visual.

I’m quite fascinated with this subject, and have some thoughts of picking up where I left off on my psychology master to be able to study it more. It’d be interesting to see if there are correlates in big-5 personality, iq, mental health etc.)

Re:Deep image reconstruction from human brain activity (2017) by azeirah on Wednesday September 12, 2018 @05:53AM (#17966937)
As far as I know, aphantasia is very real. But you can train yourself to see images in your head.

See: image streaming by Win Wenger http://winwenger.com/imstream.htm

I'd be very curious to see if you are able to see simple things in your mind's eye after practising this for a week or two

Re:Deep image reconstruction from human brain activity (2017) by ekianjo on Tuesday September 11, 2018 @11:56PM (#17965440)
I have no issue conjuring clear images when closing eyes. I guess it depends how your brain is wired and this is probably why we have ways to refer people who are good at drawing, painting, etc. They probably have a mix of clear visualization and very good hand/finger coordination.
Re:Deep image reconstruction from human brain activity (2017) by miguelrochefort on Wednesday September 12, 2018 @12:12AM (#17965496)
- Can you imagine the color of the floor, walls and ceiling at work?

- Can you imagine the color of the eyes and hairs of your coworkers?

- Can you imagine the home screen of your phone and see how many application icons can fit in a row and column?

- Can you imagine Google's logo and see the color of each letter?

- Can you imagine your car manufacturer's logo and draw it?

Re:Deep image reconstruction from human brain activity (2017) by sidmani on Wednesday September 12, 2018 @12:48AM (#17965631)
1) I can do that easily, and even can imagine the paint texture for the walls.

2) Hair for all of them, but I can only picture the eyes of the people who had unusual colors (blue, gray, green). Maybe I never paid much attention if they had normal brown eyes.

3) Row yes, but I wasn't sure about the column (4 or 5).

4) Yes.

5) easiest task on the list.

Re:Deep image reconstruction from human brain activity (2017) by miguelrochefort on Wednesday September 12, 2018 @02:01PM (#17971340)
I'm pretty sure less than 1% of people know the colors of Google's letters.
Re:Deep image reconstruction from human brain activity (2017) by jaakl on Thursday September 13, 2018 @05:30AM (#17977215)
Google has colored letters?
Re:Deep image reconstruction from human brain activity (2017) by bemmu on Wednesday September 12, 2018 @02:13AM (#17965948)
What you described is exactly how I experience things in my head as well, including that redrawing part.

I've noticed though that as I've spent years learning Japanese characters, I am somewhat better at visualizing them in my head. I can see (or "feel", as it's not really visual exactly in the same sense as seeing, although they are not just concepts but have spatial locations) whole subcomponents at a time instead of having to plot each line.

Re:Deep image reconstruction from human brain activity (2017) by dwaltrip on Wednesday September 12, 2018 @01:25AM (#17965757)
Yep, I can visualize images of some things, especially things I am familiar with or that left an impression on me (incomplete and with inaccuracies, I'm sure). I think I am also fairly visual/spatial in my thought processes.
Re:Deep image reconstruction from human brain activity (2017) by Hoasi on Wednesday September 12, 2018 @09:18AM (#17968336)
Interesting. What are your dreams like? Do they look like abstract pictures (lanes? shapes?) or have no picture at all?
Re:Deep image reconstruction from human brain activity (2017) by miguelrochefort on Wednesday September 12, 2018 @02:00PM (#17971321)
Dreams are more visual, although I can't recall ever seeing colors. There's no texture or details, just general outlines.
Re:Deep image reconstruction from human brain activity (2017) by rasz on Wednesday September 12, 2018 @12:44AM (#17965618)
>Do people actually see images of things in their head?

Yes, and Forbidden Planet "plastic educator" comes to mind :)

Re:Deep image reconstruction from human brain activity (2017) by docbrown on Wednesday September 12, 2018 @01:29AM (#17965772)
Basing this on my rough memory of abnormal and developmental psych, the article and example you’re presenting is a type of Rey-Osterrieth Complex Figure [https://en.wikipedia.org/wiki/Rey%E2%80%93Osterrieth_complex...].

Some people may be able to produce a bicycle in more details than others but that depends on how developed and healthy their brain is to use their executive functions. Without knowing all of the subjects medical history—early dementia, strokes, all the good stuff- and current health, it’d come as no surprise that even consciously we cannot produce true representations of what we saw.

Police sketches from eye witnesses may be a good thing to look at when thinking of producing images from memory. Some people have better brain health and are able to utilize many different high and low-level functions to produce more accurate descriptions. Others not so much.

Re:Deep image reconstruction from human brain activity (2017) by zadler on Wednesday September 12, 2018 @01:58AM (#17965873)
How does one improve brain health?
Re:Deep image reconstruction from human brain activity (2017) by docbrown on Wednesday September 12, 2018 @02:49AM (#17966099)
Harvard updated their Buzzfeedesque post on this topic [https://www.health.harvard.edu/mind-and-mood/12-ways-to-keep...] which spans from crossword puzzles to avoiding alcohol.

But to keep it simple: read, do puzzles, stay active, do not drink or do drugs heavily. ——

Everybody already has a genetic makeup that limits their health—especially the brain—to a preset level. Some people suffer from infantile amnesia—basically not remembering early developmental stages (2-4) and preadolescent (~10 y/o); other’s claim to remember their birth (which is silly since ability to form memories is 2 y/o+). Some have the luxury of having strong working memory^1—a fancy word for temporary memories—but suffers from lackluster short-term memory.

I’m sure you get the point I was trying to make with that mediocre explanation.

tldr: You can not change your brain to not have dementia if your genetic makeup says so. You can however delay the onset possibly by keeping your brain active on a daily basis.

[1] https://en.wikipedia.org/wiki/Working_memory

Re:Deep image reconstruction from human brain activity (2017) by tigershark on Wednesday September 12, 2018 @04:16AM (#17966453)
I don't really think that you can form memories only from when you are 2 years old. I have memories of when they removed the cast from my broken arm and I was probably 1 year and some months.
Re:Deep image reconstruction from human brain activity (2017) by docbrown on Wednesday September 12, 2018 @11:56AM (#17970081)
In certain situations, especially ones related to trauma or an altering event, it may be possible to remember it faintly. But there are many factors that may have helped you remember this.

Have you spoke about it at great lengths when older? Is it often brought up about how they took the cast off? If so, you’re looking at the idea of explicit (declarative) memory—the storing of facts and events. If over the years you are constantly reminded of this event, it is more than likely that you’re trying to generate a (possible semi-accurate) image or memory of that particular event.

As far as your second comment goes, mother tongue and languages are different all together. When you learn as a yongue age, your cerebral cortex is still developing and your mind is absorbing everything like a sponge. As you learn these words, continue to use them, that language and those procedures are going to get stored in your long-term memory and then you’ll be able to recite all of these words and form sentences without thinking twice—something we would call implicit memory which helps us with procedure memories (riding a bike, writing, etc.).

Re:Deep image reconstruction from human brain activity (2017) by sweetheart on Wednesday September 12, 2018 @08:25AM (#17967800)
From what little I know of memory recall, there is a very good chance that is a false memory if it happened before people generally start being able to form memories.
Re:Deep image reconstruction from human brain activity (2017) by tigershark on Wednesday September 12, 2018 @09:00AM (#17968125)
so even all the words of the mother tongue that you learn when you are a baby are false memories? I'm really skeptic, and I am pretty sure that mine is not a false memory.
Re:Deep image reconstruction from human brain activity (2017) by jfoutz on Tuesday September 11, 2018 @10:21PM (#17965111)
Feynman wrote about this in one of his books. it's really hard to understand how someone else understands something. but you can say, well imagine it's orange and spherical and kind of hairy, and they'll have a picture in their mind you can kinda work with.
Re:Deep image reconstruction from human brain activity (2017) by bemmu on Wednesday September 12, 2018 @02:34AM (#17966040)
From "What Do You Care What Other People Think":

I was a kid growing up in Far Rockaway, I had a friend named Bernie Walker. We both had “labs” at home, and we would do various “experiments.” One time, we were discussing something — we must have been eleven or twelve at the time — and I said, “But thinking is nothing but talking to yourself inside.

“Oh yeah?” Bernie said. “Do you know the crazy shape of the crankshaft in a car?”

“Yeah, what of it?”

“Good. Now, tell me: how did you describe it when you were talking to yourself?”

So I learned from Bernie that thoughts can be visual as well as verbal.

Re:Deep image reconstruction from human brain activity (2017) by schoen on Wednesday September 12, 2018 @12:26AM (#17965550)
Are you sure you're not thinking of the "hairy green ball thing" from his discussion of visualizing topology examples?

https://books.google.com/books?id=_gA_DwAAQBAJ&pg=PT87&lpg=P...

Re:Deep image reconstruction from human brain activity (2017) by PinkMilkshake on Tuesday September 11, 2018 @11:55PM (#17965436)
> 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.

It seems reasonable to me. To use a computer as an analogy, the set of signals produced by a webcam recording a video to a hard drive are not going to be the same as the ones of the video playing from the hard drive on to the screen.

Re:Deep image reconstruction from human brain activity (2017) by NegativeLatency on Wednesday September 12, 2018 @12:59AM (#17965675)
Or another way: the data in a frame buffer is not the same as the data in a png file.