From criticisms I&#x27;ve read of freezing a brain by infusing it with aldehyde, it destroys things necessary for brain function, such that it will be impossible to bring a brain frozen this way back in the future.<p>P.Z. Myers^1 has said (<a href="http:&#x2F;&#x2F;freethoughtblogs.com&#x2F;pharyngula&#x2F;2016&#x2F;01&#x2F;29&#x2F;how-can-you-protect-a-brain-by-destroying-it&#x2F;" rel="nofollow">http:&#x2F;&#x2F;freethoughtblogs.com&#x2F;pharyngula&#x2F;2016&#x2F;01&#x2F;29&#x2F;how-can-yo...</a>):<p>&gt;I was fixing zebrafish brains with a cocktail of acrolein, glutaraldehyde, and paraformaldehyde in the 1980s, trying to capture detailed images of synapses in the spinal cord. It worked pretty well, too. They know what they are getting out of this: an aldehyde-preserved brain.<p>&gt;What I didn’t do with my experiments in aldehyde-preserved brains was claim that I was preserving all the information necessary for nervous system function. I was quite aware that I was chemically nuking all the proteins in the tissue; I was washing out most of the chemistry; I was destroying most of the physiological information to preserve a structural skeleton of what was there, so I could see the physical arrangement of the pieces. Nothing more.<p>And later:<p>&gt;The pattern of synaptic connections is an essential part of the story, but it is not sufficient. A simple counterexample: consider the effect of MAO inhibitors and various antidepressants. They modulate the activity of the brain by affecting the intercellular concentration of neurotransmitters. ...<p>&gt; These things are all destroyed by fixation. The information is no longer there.<p>&gt; If this organization is so confident that they have preserved all the necessary information, I’d like to know why they’re playing around with just the first step of the problem, doing so in impractically complex organisms, and not working on the necessary step of recovering that information. That’s the real test.<p>&gt; Take a simpler organism, like a fruit fly or a nematode. Kill it, fix it, freeze it, vitrify it. That should be trivial at their tiny scale. Then rebuild a fly brain from the extracted information and show me that it still knows how to walk, fly, eat, court, and mate.<p>It&#x27;s reasonably convincing<p>[1] I know he&#x27;s considered somewhat controversial, but he&#x27;s a biologist here speaking a sub-topic in biology he&#x27;s worked in. Even if you don&#x27;t like him, this can&#x27;t be dismissed out of hand.