What is true for a neuron ?

Whatever method we use to extract meaning from data, truth seems to be elusive. Assume two event A and B are 90% correlated, meaning in 90 % of the time A precedes B. Is there a cause and effect between A and B ? What does it mean “precede” ? Day precedes night and summer precedes fall. So without a time frame, we cannot correlate event A and B. Assume the correlation is 100%. Does that mean cause and effect relationship ? We don’t know, maybe we did not pool enough data, or the time frame is wrong…

How is this related to my neuron ? I can’t decide when events are correlated or not, therefore I cannot move the data upwards in the next layer for further processing. How is this problem solved in the biological neuron ? I inferred from the 1960, cat experiment of Torsten Wiesel, that synaptic plasticity must stop in the lower layers of the primary visual cortex , and must stop rather early in life. I also assumed that the same process must happen on upper layers as well, but within a longer time frame. I also found a recent article (Rejuvenating Mouse Brains …) talking about a perineuronal net, which prevents neurons from forming new synapses. This tells me that we decide rather randomly about what truth is, base on available data, up to some time period, and the subsequent data is classified base on this old data, that cannot be changed anymore (or perhaps if extremely difficult to change but not impossible ).

So how does this help me ? I decided that I also need to stop the “learning” process at some point, otherwise data keeps changing resulting in always changing conclusions. But when to stop it ? Hard to say, it depends on the available data. If available data is enough to represent “reality” than I can confidently stop the learning process. But what does it mean “represents reality”… I’m thinking that reality is whatever sensory data is available for analysis, coupled with the environment in which the neuron evolves coupled with some evolutionary programming, objectives such as surviving. This all looks way to philosophical to be of any practical use but perhaps all is statistics underneath..

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