Your dog likes it when you smile at it

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The discussion centers around the reliability of functional magnetic resonance imaging (fMRI) as a method for studying brain activity. It highlights the technique's propensity for false positives, illustrated by an experiment where a dead salmon was placed in an fMRI scanner and showed brain activity in response to images of human faces. This example underscores the indirect nature of fMRI, which measures blood flow and metabolic activity rather than direct neuronal activity, raising questions about the correlation between these measures and actual brain function. The conversation also touches on the longevity of certain brain cells after death and the humorous implications of the salmon study, while acknowledging the emotional connections people have with their pets. Overall, the thread emphasizes skepticism regarding fMRI's validity in neuroscience research.
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Short Science mag news story here.
Brain scans similar to humans.
 
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It should be noted that functional magnetic resonance imaging (fMRI), the technique that the study is based on, have been notoriously unreliable and subject to many false positive. For example, to demonstrate the ease of discovering false positives, researches placed a dead salmon from the supermarket into an fMRI scanner and, using the same analysis techniques used in many published papers, found signs of activity in certain regions of the brain when showing the salmon pictures of human faces. Furthermore, fMRI is a very indirect measure of brain activity, measuring things like increased blood flow or increased metabolic activity in different areas of the brain. To what extent these observables correlate with the underlying activity of neurons is still unclear.

Here's a nice piece from a few years ago highlighting some of the issues with fMRI and other similar brain scans:
http://blogs.scientificamerican.com/guest-blog/controversial-science-of-brain-imaging/
 
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Ygggdrasil said:
researches placed a dead salmon from the supermarket into an fMRI scanner and, using the same analysis techniques used in many published papers, found signs of activity in certain regions of the brain when showing the salmon pictures of human faces.
:doh:
 
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Ygggdrasil said:
researches placed a dead salmon from the supermarket into an fMRI scanner and, using the same analysis techniques used in many published papers, found signs of activity in certain regions of the brain when showing the salmon pictures of human faces.
Wait, I may need to amend my previous post. Exactly what human faces were shown to the dead salmon?

https://image1.masterfile.com/getIm...ng-a-large-king-salmon-caught-on-a-salmon.jpg
854-02955512em-commercial-fisherman-holding-a-large-king-salmon-caught-on-a-salmon.jpg
 

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BillTre said:
Short Science mag news story here.
Brain scans similar to humans.
With or without teeth? :)
 
Greg Bernhardt said:
With or without teeth? :)
It took me WAY too long to decode what you were asking. o0)

:smile:
 
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Ygggdrasil said:
It should be noted that functional magnetic resonance imaging (fMRI), the technique that the study is based on, have been notoriously unreliable and subject to many false positive. For example, to demonstrate the ease of discovering false positives, researches placed a dead salmon from the supermarket into an fMRI scanner and, using the same analysis techniques used in many published papers, found signs of activity in certain regions of the brain when showing the salmon pictures of human faces. Furthermore, fMRI is a very indirect measure of brain activity, measuring things like increased blood flow or increased metabolic activity in different areas of the brain. To what extent these observables correlate with the underlying activity of neurons is still unclear.

Here's a nice piece from a few years ago highlighting some of the issues with fMRI and other similar brain scans:
http://blogs.scientificamerican.com/guest-blog/controversial-science-of-brain-imaging/
Now that hurts Yggg! I know my recently deceased dog, Ming, would respond to me smiling by waging his tail. Maybe dead salmon have superpowers we just don't know about yet. Ok, I will temp ban myself now. :frown:
 
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Evo said:
Now that hurts Yggg! I know my recently deceased dog, Ming, would respond to me smiling by waging his tail. Maybe dead salmon have superpowers we just don't know about yet. Ok, I will temp ban myself now. :frown:
Hmmm... Not so sure EVO... :DD
Just as digestion may successfully continue for a bit after death, so might photoelectric-like retina cells. The resulting electrical signals might then fire a few surviving neurons just like the semi-living nerve tissue in frog legs, which can cause them to jump when electrically stimulated. :wideeyed:

And then... domestically bred salmon might still respond to human faces just like my wife's tropical fish that frantically rush to the front top tank-side when she approaches to possibly feed them. Or like her fuzzy poodle (Quincy), who always equates a smile with food and automatically wiggles his tail like the fish. Any facial expression actually. Ok, now I'm banned too. At home and PF. :oops:

Wes
 
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Neurons, being high metabolism cells, will be among the first to die after organismal death. I am guessing within minutes.
Skin, hair, connective tissue, and cornea cells can all last several hours after death.
Cornea cells can be removed up to 24 hours after death and still be useful for transplants.
 
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BillTre, thanks for making more explicitly clear, the lack of life-after-death of most cells, especially neurons. I should have emphasized that I was joking. :smile:

Although I still view with wonderment that some simple brain-cells, like those of a frog, seem to withstand freezing temps while they hibernate at near death. And how do chickens keep their balance running when their head is missing? Of course all frog brain-cells have to do, when they thaw, is remember that flies taste good. And obviously the chicken head is only for remembering... that flies taste good. And what is it that flies remember when they warm back up the next season? Ick. ?:)

Finally, on a more serious note, I should have added to my previous post, that my condolences go out to Evo and all whom have loved and lost a pet. They become almost like our children. They should live longer than us. Been there, done that. :frown:

Wes
...
 
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