Friday, April 07, 2006

investigating the role of fast vs. slow components in learning

I've been working during the last days but haven't been able to report on any of it. Mainly because I have not made as much straightforward progress as I can easily explain.

I've been working on evolving learning on a continuum in the abstract scenario. I have managed to evolve circuits that can 'memorise' features on a continuum without the need to introduce any parameter-changing rules.

How do they memorise the features? The key to answering this question is in the interaction at very different time-scales between the 'neurons' of the circuit.

Currently I am performing experiments in this one-shot remembering features on a continuum where the delay can vary greatly (between 10 and 100 units of time).

From 20 evolutionary runs using 10 node CTRNNs I observed that there were, roughly, 2 possible types of evolved behaviors: discrete categorisers or generalisers. The discrete categorising circuits are unable to differentiate most of the features within the continuum and rather they make up 2 or 3 categories for them. Either small and large, or small, medium and large type of features. The ones that make 3 categories score better than the ones that only make 2 categories. The generalisers do much better and can distinguish between many more signals, without making any obvious categories a priori.

In terms of the mechanisms available, there's 10 nodes and they can act in very different time-scales. The fastest ones have a time-parameter of 1 while the slowest can be as slow as 140 units of time. This parameter describes the way in which state leaks out of this component. One thing is common among the categorisers, they do not make use of slow acting neurons, but only fast-acting ones. Whereas the generalisers make use of both.

For the purpose of determining the role of fast versus slow acting components in the circuit in this memorisation task, the best evolved agent's time parameters were studied and from it we defined what slow acting neuron ranges and what fast acting neuron ranges where needed to solve the task. Slow acting then corresponded to neurons with time parameters between (50 and 100) while fast acting nodes where defined to be between (1, 7).

To observe the role of this different components I am running evolutionary runs while the circuit is constrained to have different numbers of fast/slow neurons. I am using a 10 node CTRNN so there are 11 cases. In one extreme is the case when all neurons are restricted to the fast range, then there is the case when one is restricted to be slow and the rest restricted to be fast, and so on until all neurons are restricted to be slow. I am running 10 evolutionary runs using different seeds for each case. The intuition is that neither of the extremes do well, and that the optimum for the learning task lays somewhere in-between, possibly with more fast neurons than slow neurons. The resulting curve should be interesting.

On the other hand, I have not managed to evolve circuits that can continue to remember the feature after they have had to make a first decision. I am working on changes to the current evolutionary methodology that will lead to success here. One of the changes that I will try might be to add a feedback input (I have to explain why I think this is important but will do so later on). Also I must simply wait longer (more generations) as well as try larger circuits (currently the biggest has been a 10 node one).

On a completely different note, I have started to design the experiments in the embodied version of this memorisation task loosely inspired on behavioral plasticity observed in C. elegans. A similar form of learning to imprinting has been observed in these organisms. In particular, it has been observed that the animals that were cultivated normally with food at temperatures ranging from 15C to 25C migrate to the cultivation temperature on a temperature gradient and move isothermally at that temperature. By contrast, the animals migrate away from the temperature at which they were previously starved. They don't call it imprinting, but it is a very appropriate behaviorual paradigm to continue to study learning and memory in the embodied version. I will say some more on this soon.

39 Comments:

At 3:09 am, Anonymous Anonymous said...

免費線上成人av影片免費線上成人av免費線上影片av免費情色av影片免費成人av線上看免費成人av女優台灣av女優貼圖台灣av女優台灣av卡通台灣av貼片台灣av線上影片台灣av18台灣av卡通av女優卡通av十大av女優動畫av免費亞洲av下載影片免費下載av影片免費下載avgirls免費日本av免費成人av情色電影免費線上看av片av免費試看短片av圖庫av女生裸體照片av女郎av女貼av女傭av女傭的小胸部av女優av女優-女人av女優.成人情色av女優104試看av女優無碼電影av女優無碼影城av女優照av女優照片av女優生活av女優的照片

 
At 7:53 am, Blogger 尾牙大餐 said...

巨奶女優大奶性交性愛淫蕩淫慾淫亂淫婦淫妹淫叫淫水淫女情慾情色做愛限制級波霸口交18禁貼圖寫真視訊援交露點爆乳潮吹裸體裸照裸女愛愛無碼尋夢視訊聊天

 
At 7:56 am, Blogger 美國 said...

淫妹淫叫淫水淫女情慾情色做愛限制級波霸口交18禁貼圖寫真視訊援交露點爆乳潮吹裸體裸照裸女愛愛無碼尋夢視訊聊天a漫a片a圖一夜情一葉情人妻激情情色寫真美女自拍

 
At 4:36 am, Anonymous Anonymous said...

may the blessing be always with you!! ........................................

 
At 10:21 am, Anonymous Anonymous said...

你可以從外表的美來評論一朵花或一隻蝴蝶,但你不能這樣來評論一個人........................................

 
At 2:54 am, Anonymous Anonymous said...

thank u........................................

 
At 12:59 pm, Anonymous Anonymous said...

狗健康
寵物床

 
At 4:02 pm, Anonymous Anonymous said...

一棵樹除非在春天開了花,否則難望在秋天結果。 ..................................................

 
At 6:30 am, Anonymous Anonymous said...

haha~ funny! thank you for your share~........................................

 
At 3:41 am, Anonymous Anonymous said...

pleasure to find such a good artical! please keep update!!.............................................

 
At 3:16 pm, Anonymous Anonymous said...

最美好的東西是看不到、摸不到的,但可以用心感覺。 ..................................................

 
At 10:59 pm, Anonymous Anonymous said...

量力而為,別勉強了,Cut your coat according to your cloth. ....................................................

 
At 9:04 am, Blogger 哲宇皓云 said...

喘口氣,看個文章,謝謝您的格子囉~~..................................................

 
At 3:32 pm, Blogger EleanoreBla昭彥 said...

仇恨是一把雙刃劍,傷了別人,也傷了自己............................................................

 
At 7:03 am, Blogger BryannaR22369 said...

After a storm comes a calm...................................................

 
At 2:39 am, Anonymous Anonymous said...

Keep in contact. Good Luck..................................................

 
At 5:47 am, Blogger 則惠 said...

路過看到好的blog,不推對不起自己.................................................................

 
At 7:39 pm, Blogger 原秋原秋 said...

知識可以傳授,智慧卻不行。每個人必須成為他自己。......................................................................

 
At 6:55 am, Anonymous Anonymous said...

人不能像動物一樣活著,而應該追求知識和美德....................................................................

 
At 5:43 pm, Anonymous Anonymous said...

It takes all kinds to make a world.............................................................

 
At 12:06 pm, Anonymous Anonymous said...

Hello~安安唷~很高興見到你哦!!............................................................

 
At 12:06 pm, Anonymous Anonymous said...

噴泉的高度,不會超過它的源頭。一個人的事業也是如此,它的成就絕不會超過自己的信念。.................................................................

 
At 8:16 pm, Anonymous Anonymous said...

什麼樣的學習計畫並不重要,重要的是你是什麼樣的人。............................................................

 
At 12:32 am, Anonymous Anonymous said...

留言支持好作品~加油!期待進步和更新..................................................................

 
At 6:52 am, Anonymous Anonymous said...

要繼續發好文喔^^..................................................................

 
At 1:29 pm, Anonymous Anonymous said...

一棵樹除非在春天開了花,否則難望在秋天結果。..................................................

 
At 4:23 am, Anonymous Anonymous said...

好多很有用資訊...感謝你的分享喔............................................................

 
At 11:46 pm, Anonymous Anonymous said...

早點休息阿,身體健康很重要的!..................................................................

 
At 1:04 pm, Anonymous Anonymous said...

好的部落格,希望您能繼續堅持!!!............................................................

 
At 8:42 am, Anonymous Anonymous said...

教育無他,愛與榜樣而已............................................................

 
At 11:53 am, Blogger 甄賴盈賴盈 said...

愛,拆開來是心和受兩個字。用心去接受對方的一切,用心去愛對方的所有。......................................................................

 
At 3:15 pm, Blogger 許泓v辛 said...

做好事,不需要給人知道,雖然只是一件微不足道的事,但我相信,這會帶給我快樂。..................................................

 
At 9:28 am, Anonymous Anonymous said...

男女互悅,未必廝守終生,相愛就是美的。.................................................................

 
At 5:13 am, Anonymous Anonymous said...

Every why has a wherefore.............................................................

 
At 1:01 pm, Anonymous Anonymous said...

這個部落格好好好~棒棒棒..................................................................

 
At 2:42 am, Blogger 孫邦柔 said...

真得很不錯的blog,加油哦............................................................

 
At 3:50 am, Anonymous Anonymous said...

生存乃是不斷地在內心與靈魂交戰;寫作是坐著審判自己。..................................................

 
At 7:39 am, Anonymous Anonymous said...

很精彩的部落格 期待你的繼續加油..................................................

 
At 2:20 pm, Blogger 孫邦柔 said...

出遊不拘名勝,有景就是好的..................................................................

 

Post a Comment

<< Home