<table><tr><th>From:</th><th>on behalf of Ed Boyden</th></tr><tr><td>Sent:</td><td>Tuesday, July 22, 2014 2:55 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>

Sure... I guess I was thinking of this from a info theory standpoint, where if you can't recover the original, some info was discarded. But this is a tricky way to think. Best to stick to thinking about what one part of a network is computing, based upon what other parts of the networks will do with the signals received.

On Tue, Jul 22, 2014 at 10:51AM, jeffrey E. <jeevacation@gmail.com> wrote: > Not sure if discarding , as opposed to a function with a defined limit > output .

>

> On Tuesday, July 22, 2014, Ed Boyden < wrote:

>>

» 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/m

>> > oney-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
>
>
>
> --
> please note
> The information contained in this communication is confidential, may
> be attorney-client privileged, may constitute inside information, and
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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 KIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0">

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