User:Rjlabs/Brain mapping frequently asked questions

Brain Mapping Frequently Asked Questions...

This is a space to ponder what questions people might have about the various brain mapping projects and related scientific topics. For a list of projects see List of topics related to brain mapping. News and specifics on those ongoing projects will be revealed over time, and scientific information flowing from them will get published and eventually find its way to Wikipedia. The purpose of this list is not necessarily to get answers to questions, but to perhaps help inform content creation. Content originators may be inspired to cover items of interest revealed in rough form here, organizing secondary information, and publishing it in standing or new main articles.

Feel free to add and edit here. Ask as many questions as you like, but try to keep it to one focused question per section. Remember Wikipedia is not a blog, webspace provider, or social networking site...This will be a temporary page but may exist for some time as the major projects take time to unfold. The goal is to help content originators and integration editors potentially cover items of interest.

Will the map contain more than physical structure?
If you look at a single human brain as a “computer” it basically stores and processes information. At the end of the day "all it does" is produce cognition, affect and behavior. The brain mapping project envisions hundreds of petabytes of data, owing to the vast number of brain cells and the even more daunting number of interconnections between them.

Pondering "limits", compare the mapping database size, to the data size of Wikipedia, which strives to encompass “all knowledge”, and contains cross links (categories, "see also" links, outside references, references to people, places, things, has disambiguation entries, etc., plus has full word and term indexing). Yet the total size of wikipedia is only a tiny fraction of what is envisioned in the brain mapping projects in terms of data storage requirements. If a single brain is that "big" in terms of capacity (the data size envisioned in brain mapping), why doesn't one brain easily hold the entire contents of Wikipedia?

All of Wikipedia will not fit into a single human brain. Its knowledge base has been created by millions of people, over hundreds or thousands of years. It supposed to be a proxy for “all knowledge”. Why is it that the human brain mapping project has a much larger data set? Is all of the mapping interconnect information capable of producing greater knowledge?

And, on the other end of the spectrum, what exactly is Wikipedia missing that is so rich data wise? Rick (talk) 01:40, 4 March 2013 (UTC)

What data is to be collected
Above leads into this question. Imagine we are taking “slices” of the brain, horizontally and vertically. Is every neuron on each slice separately identified? Every neuron to neuron connection identified? Are these slices a longitudinal study from birth to death? Rick (talk) 01:40, 4 March 2013 (UTC)

How is the data at the cell level aggregated into larger physical entities?
Many areas of the brain are physically differentiable. Are those areas (above the level of a single cell/neuron) to be also mapped structurally in 3D? How do the 2D slices above get aggregated into 3D higher level structures? Rick (talk) 01:40, 4 March 2013 (UTC)

What mapping already exists from known physical entity inside the brain to function?
Much of the functional knowledge seems to have evolved from highly specific injuries (targeted puncture wound, gunshot wound, surgical removal, specific trauma, etc.) followed by extensive rehabilitation after. And, more recently, clever fMRI studies. What is the data structure containing this functional / historically collected information? How accurate is this functional data mapped to specific physical structure? Down to the cubic millimeter? Smaller?

What is the current level of knowledge of how a single human neuron operates?
Is the neuron the fundamental (most atomic) building human information processing building block? Do we know how a single neuron operates? How many “types” of neuron cells there are, and what are the characteristics of each? Is there anything at the sub neuron level that contributes substantially to "computation"?“ How important is what's going on in the nucleus, including "preprograming" or "predisposition" controlled by genetics? Rick (talk) 01:40, 4 March 2013 (UTC)

What is the current level of knowledge of how groups of neurons function together?
Mapping individual neurons and synapses is fine but do groups of neurons have behavior together that is not the simple sum of the individual neurons in any particular bundle? Rick (talk) 01:40, 4 March 2013 (UTC)

Will the map basically provides a “circuit diagram”?
Will the map basically provide a “circuit diagram of 3D routes taken, and interconnections along the way, basically just an “electrical wiring diagram”. At any point in time interconnections between neurons are fixed. At that point are the neural circuits equivalent to a programmed gate array, just a fixed logic circuit? That fixed logic gets a specific binary input, computes in a fixed way, and produces a binary output? No "free will" in-the-moment, just straight computation? Rick (talk) 01:40, 4 March 2013 (UTC)

How does “voting” occur when multiple neurons are involved?
Do we understand neural voting? Or is there a layer of complexity above the single neuron such that a simple "circuit diagram" is not all that valuable in terms of describing the higher level function? Rick (talk) 01:40, 4 March 2013 (UTC)

Is there computation involved in neural plasticity?
A "circuit diagram" implies fixed logic that's programed and in place. Presented with specific input there is mapped, specific output. However if plasticity is involved, the constant movement of connections makes the hard logic potentially quite dynamic. The same binary input (at different points in time) produces radically different computations and radically different binary output? Rick (talk) 01:40, 4 March 2013 (UTC)

Is the neuron 100% “digital” or are there analog elements?
Do neurons partially fire? Is the rate of firing a complex and an important thing? (There is no central "clock"?) How about reset time between firings, is it fixed? Is there a "strength" element of firing? Will this type of information make it into the neuron map? Rick (talk) 01:40, 4 March 2013 (UTC)

Do general “fields” of activity impact neural signaling?
Do general “fields” of activity (external to the individual neural connections and bundles themselves) affect neural signaling? Perhaps a high state of general ANS arousal? Substantial anxiety, "frazzled nerves", “Tingles up the spine”, etc? Intense physical or emotional trauma? How will that "general field" effect be recorded and mapped? Rick (talk) 01:40, 4 March 2013 (UTC)