Why Neurons Have Thousands Of Synapses, A Theory Of Sequence Memory In Neocortex


#21

Thank you @subutai for your response.


#22

Hi @subutai,

what is active presynaptic cells?

“The matrices “delta D” are added to the current matrices of permanence values at every time step” means delta D will be added with matrix D, that is correct?

In part 5 of paper, eq( 6) is doing reinforcing and punishing, and eq(7) is do something like punishing, that is correct?


#23

@Niki There are quite a few posts on the forum mentioning presynaptic cells. Our search page is quite good.


#24

Thanks @rhyolight , I will check them.


#25

If cell a connects to cell b (i.e. cell a forms a synapse onto cell b’s dendrite), then cell a is a presynaptic cell for cell b. Cell b will be a postsynaptic cell for cell a.

Yes. Delta D^d_ij will be added to D^d_ij

Yes, that’s right. Eq 7 is a much weaker punishment in case a cell was predicted but did not become active later.


#26

Thank you for your reply @subutai.


#27

Hi @subutai,

Are the three states “Active, predictive, and nonactive” mutually exclusive?


#28

No, an HTM Neuron can be active and predictive at the same time.


#29

I’ve just started reading the paper, however I’m wondering what operation is denoted by the slash in the graphic.

I think it would become obvious later on, but it’s important to me while I’m still at pages 3-4 to already know it.


#30

It just denotes a linear operation, as opposed to a threshold. The proximal synapses (green) tend to have a linear impact on the cell body. In this paper, we focused almost completely on the blue context synapses and didn’t discuss the proximal ones too much.


#31

Hi, I am new to HTM community.

Several years ago, I read the HTM whitepaper published in 2010. Is there any update on the theory between that and this paper, which is published in 2016?


#32

Yes, see our latest paper: Why Does the Neocortex Have Layers and Columns, A Theory of Learning the 3D Structure of the World.


#33

Thanks but I know there were some updates on the theory between the 2016 paper and the latest paper which is very interesting. I am asking what has changed between 2010 and 2016, because the following page says that the whitepaper is obsolete.