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outputs. Self-awareness forms as a result of an active interaction with the environment. Perinatal maturation of cortical anatomy and the emergence of 1/f cortical dynamics offer the proper substrate for the gradual consciousness to not only humans but also to other mammals. /23

In cerebellum inputs from mossy fibers exhibit periodicity(5-14Hz range). One can speculate that consciousness arises in self-organized, oscillatory parts of the brain. Spontaneous activity alone however does not give rise to consciousness, as system without output would generate meaningless/22

However, both of these structures are unable to sustain large scale self organized spontaneous patterns. They have very low amplitude local mean field potentials, which is surprising given its highly parallel structure. High potentials are observed only given strong synced input. /21

both have large numbers of parallel inhibitory loops that are funneled back into a relatively small hub with widespread projections(deep cerebellar nuclei and thalamus respectively). Maybe strictly local organizations provide calculations for precise spike timing and high temporal coordination. /20

there have very long smooth dendrites and they are flat like Purkinje cells. Pallium innervates internal pallium, SN pars reticulata. The major target of GABAergic neurons is the subtalamic nucleus. Also inhibitory terminals innervate various thalamic nuclei. Cerebellum and the basal ganglia /19

Most of the neurons in the basal ganglia are GABAergic. The striatum consists mostly of medium spiny neurons and is innervated mostly by the neo- and allo cortex. There are also basket and cholinergic interneurons mixed among MSNs. External pallium has similar organization, except principal cells/18

processing, with the ability to either return input information to its origin or feed it to another cortex area. There is little crosstalk between parallel inputs in the basal ganglia. The basal ganglia includes striatum, globus pallidus(ext and int), and substantia nigra. /17

This anatomy suggests that cerebellar "modules" process incoming inputs locally but need to consult or inform the rest of the cerebellum about the locally derived computation. Similarly to cerebellum, the basal ganglia have major inhibitory steps in the loop. Its organization suggests parallel/16

perpendicular to dendritic trees of Purkinje cells. Each Purkinje cell receives at least input from at least 200000 parallel fibers. The third loop is a "shortcut" that originates in the inferior olive of the brainstem, bypasses granule cells and terminates directly on Purkinje cells. /15

Golgi cells inhibit granule cells. Cerebellum has three ways it processes information. The first short loop involves mossy fibers from the brainstem that innervate deep cerebellar nuclei. Two other longer loops address thousands of granule cells. Granule cells form thousands of thin fibers/14

dendritic trees. However their dendritic trees are flat and hardly touch each other. Small granule cells packed under Purkinje cells have very small dendrites and recipe inputs from 2-5 mossy fibers. Purkinje cells are innervated by granule, stellate(dendrites) and basket cells(somata)./13

There is also no substantial variation in organization within it. There are 4 types of GABAergic cells in cerebellum(Purkinje, basket, stellate and Golgi cells) as well excitatory granule cells. Principle cells are Purkinje cells(kind of like pyramidal cells) that have most elaborate extensive/12

monitor all motor and posture related information and execute precise movements. Anteriori and posterior lobes compute movements while the ancient flocculonodular lobe is mostly for regulating posture and eye movements. There is no corpus callosum or other fast expensive connections. /11

complex(1/f) self-organized, but what about other types of wiring? Cerebellum and basal ganglia are such examples. Cerebellum is truly a locally organized structure -- it has the same amount of cells as the rest of the brain packed in 10% of its total volume. Cerebellum evolved to /10

and is perfect for processing correlated environment data with its "small world" connectivity while the hippocampus gives rise to the sense of individuality with its random connections that can bring and tie random things together. Cortex`s computations are global, everybody, gets informed, it is/9

information which implies that any system capable of integrating information is capable of subjective experience. Perhaps the approach is to identify which brain structures support consciousness. Another general agreement is that neocortex is essential for awareness/8

physiology. Consciousness is a direct product of the brain, but the "hard" question is why are we aware of certain processes but not the others. Sagan also ignores the brain`s embedded nature in the body and the environment. Tononi defines consciousness as an ability to integrate and differentiate/7

should be some kind of mechanism that eliminates spontaneously occurring oscillations. Consciousness is a difference between a wink and a blink, declarative and nondeclarative memories, it is also a hypernym with no definition. Sagan suggests that mind is a product of a brain, its anatomy and/6

other electrical devices can run without oscillatory clocks if there is some other temporal level of computational coordination. In this case the brain would have to redefine all the neuronal time constants, and eliminate excitation/inhibition that are natural forces of oscillations. Also there /5

Can a brain without oscillations function properly? In principle, if an alternative timing mechanism exists to perform that function. The real question is whether such a mechanism is possible. What does not seem to be essential is a rhythmic aspect of synchrony. In principle, TVs, computers and /4

A pure test of completely eliminating oscillations and observing behavioral effects cannot be performed, since oscillations are embedded in the system; removing them dismantles the whole system. Moreover, since oscillations are emergent properties, they cannot be extracted independently. /3

oscillations are sometimes not observed during tasks (though absence of observation doesn't prove absence), or that reducing oscillations didn't affect behavior (without confirming complete elimination). However, all oscillation studies are correlational, and correlation does not imply causation. /2

Cycle 13
Tough problems

CitiCorp, an infamous skyscraper, was built to be an oscillator just because it is easier to build an oscillator with a damper than a building without resonant features. Could the same apply to our brain? The main criticisms of oscillation research are that/1

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a result of annihilation by some other oscillator. Like a high-frequency stimulation of STN reduces Parkinson tremor. Unfortunately, there is no general theory of oscillatory networks of multiple interacting oscillators. /36

Cross frequency phase synchrony was observed between alpha and gamma during mental arithmetic tasks and there is a positive correlation between task load and magnitude of phase synchrony. Desynchronization of alpha is not well studied, it almost always enhances gamma oscillations so maybe it is /35

be perceived at a glance. Reaction time histograms also show 25 and 100ms periodicities, corresponding to gamma and alpha oscillation cycles. Gamma cycle could be a time limit for temporal resolution in both visual and somatosensory systems. What about phase synchrony?/34

cycle is the "magic" number (7+-2) of items that can be stored in the working memory. This multiplexing mechanism could provide a link between short term and episodic memory. Neocortical alpha can also modulate gamma power, but alpha can only nest 5 items, which the amount of objects that can /33

span of working memory in humans. There is no direct support for this, but a major innovation of this model is that it does not require reverberating circuits(memory is not "stored" in synapses). Indirect support of this is that the amount of the "gamma" items stored in one theta /32