<table><tr><th>From:</th><th>d Boyden &lt;</th></tr><tr><td>Sent:</td><td>Tuesday, July 22, 2014 2:49 PM</td></tr><tr><td>To:</td><td>jeffrey E.</td></tr><tr><td>Subject:</td><td>Re: my guess is biological hash functions exist</td></tr></table>

Absolutely! Computation means discarding information (e.g., sensory information being transformed into a decision requires discarding some of the info -- a passive photocopier does no computation), and a hash is basically doing that, but a one-way function, and towards some fixed length. I think that is probably the way brains error check, no?

Best,

Ed

On Tue, Jul 22, 2014 at 9:04 AM, jeffrey E. <jeevacation@gmail.com> wrote:
> https://www.khanacademy.org/economics-finance-domain/core-finance/money-and-banking/bitcoin/v/bitcoin-cryptographic-hash-function
> 
> --
> please note
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## Ed Boyden, Ph. D.

Leader, Synthetic Neurobiology Group

Associate Professor, MIT Media Lab and McGovern Institute,

Departments of Biological Engineering and Brain and Cognitive Sciences Co-Director, MIT Center for Neurobiological Engineering New York Stem Cell Foundation-Robertson Investigator MIT, Room E15-421, 20 Ames St., Cambridge, MA 02139 email - esb@media.mit.edu office - (617) 324-3085 cell - (650) 468-5625 fax - (617) 253-6285 skype - eboyden3 web - http://syntheticneurobiology.org twitter - http://twitter.com/eboyden3 <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.O.dtd"> <plist version="1.0">

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## Ed Boyden, Ph. D. (cont.)

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