I think the key is to see the gene switching not as an information store per se but as part of a larger dynamic process (which might be similar in principle to simulated annealing), in which the contributions of whole neurons (e.g., the outputs) are switched in some way meaningful to the dynamic.
--- On Wed, 12/3/08, Ed Porter <[EMAIL PROTECTED]> wrote: Ben, I basically agree. There many things going in the human brain. There are all the different neuro- chemicals, receptors, and blockers, some of which are not only effective across individual synapses, but often across broader distances. There is the fact that neuron branches can apparently grow in directions guided by chemical gradients. There are synchronies and brain waves, and the way in which they might spatially encode or decode information. And so on. So I admit the brain is much more complicated than most neural net models. But I have not seen any explanation of how changes in gene expression in a neuron's nucleus would store memories, even given the knowledge that the epigenome can store information. If there is such an explanation, either now or in the future, I would welcome hearing it. Ed Porter -----Original Message----- From: Ben Goertzel [mailto:[EMAIL PROTECTED] Sent: Wednesday, December 03, 2008 3:24 PM To: agi@v2.listbox.com Subject: Re: [agi] Lamarck Lives!(?) On Wed, Dec 3, 2008 at 3:19 PM, Ed Porter <[EMAIL PROTECTED]> wrote: > Terry and Ben, > > > > I never implied anything that could be considered a "memory" at a conscious > level is stored at just one synapse, but all the discussions I have heard of > learning in various brain science books and lectures imply synaptic weights > are the main place of our memories are stored. Nevertheless, although it's an oft-repeated and well-spread meme, the available biological evidence shows only that **this is one aspect of the biological basis of memory in organisms with complex brains** There certainly is data about long-term potentiation and its relationship to memory ... but the available data comes nowhere near to justifying the sorts of assumptions made in setting up formal neural net models, in which synaptic modification is assumed as the sole basis of learning/memory... ben g ------------------------------------------- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?&; Powered by Listbox: http://www.listbox.com agi | Archives | Modify Your Subscription ------------------------------------------- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244&id_secret=120640061-aded06 Powered by Listbox: http://www.listbox.com
