|To explain the functions of the brain by functional areas (localization theories) remained and remains unsuccessful. The function lies in the network, so one conclusion from the dilemma. The connectome images show a different structure. There, fibers from connected neurons are shown. An excitation runs via synaptically connected neurons to the target organ. These synaptic chains become active with all their divergence and convergence, not the local areas. So these synaptic chains realize the functions. With this assumption, the astrocytes are not located in functional parts, but between them. With current knowledge, the paradigm shift to connectome structure is long overdue The intensive shaping of localization theories makes rethinking difficult.|
The previous division into functional areas
Looking for the functions of the brain in locally definable areas is understandable. In contrast to the machines, the functional blueprint was/is not known. From the recognized structure its function(s) is deduced. This gives rise to a number of localization theories. And these shaped thinking for over 2000 years (literature: localization theories from antiquity to the present by Edwin Clarke/Kenneth Dewhurst). Locally definable parts fulfill specific functions. Searching Google "Brain Functional Outline" reveals structural parts. Why is this error not noticed?
Despite immense effort, it is not possible to gain a functional understanding of the brain. In the local structure, the functional parts consist of nerve tissue, i.e. of mixed neurons and astrocytes. The neurons do and the astrocytes help, are auxiliary cells.
The local theories have a major flaw. An area or a cell group has far too few synaptic inputs to be able to make global decisions. This is well formulated in the Wikipedia article Spiegelneuron: A neuron can be networked in many ways, but it is not an intelligent agent (homunculus). Highly complex things, such as the intentions of others, could only be represented in neural networks that are at least as complex.
The connectome shows a different structure
The connectome research searches very filigree. The connections between the neurons are of interest. The connectome wants to represent the entirety of all connections between the neurons of a nervous system. Graphically, this results in a plethora of fibers. Area boundaries are absent. The excitations are passed on from neuron to neuron via synapses (chained dynamic equilibrium, pathways via connected neurons). With this structure, the so-called connectome structure, it is quite understandable that the countless fibers are functionally concentrated in some places. The connected neurons have to go somewhere structurally. But these cores and areas are structure. At most, fragments of a functional part are visible in local structures, and fibers for other functions also run through there. Similar considerations here. These fibers realize the functions in combination and by means of convergence, divergence and inhibition. I.e. these are the functional parts and not the local areas. The connectome structure does not have the shortcoming of the missing input information. The amount of areas is manageable; the amount of connectome fibers does not. This is how it is described in Wikipedia. This is the only way objects/faces etc. can be recognized extremely quickly. But these pre-embossed tracks appear inflexible. Thesis: The flexibility is achieved by the many astrocytes.
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