Rodolfo Llinás, for example, proposed that consciousness results from recurrent thalamo-cortical resonance where the specific thalamocortical systems (content) and the non-specific (centromedial thalamus) thalamocortical systems (context) interact in the gamma band frequency via synchronous oscillations.A number of studies have shown that activity in primary sensory areas of the brain is not sufficient to produce consciousness:  it is possible for subjects to report a lack of awareness even when areas such as the primary visual cortex (V1) show clear electrical responses to a stimulus. Higher brain areas are seen as more promising, especially the prefrontal cortex, which is involved in a range of higher cognitive functions collectively known as executive functions. There is substantial evidence that a "top-down" flow of neural activity (i.e., activity propagating from the frontal cortex to sensory areas) is more predictive of conscious awareness than a "bottom-up" flow of activity. The prefrontal cortex is not the only candidate area, however:  studies by Nikos Logothetis and his colleagues have shown, for example, that visually responsive neurons in parts of the temporal lobe reflect the visual perception in the situation when conflicting visual images are presented to different eyes (i.e., bistable percepts during binocular rivalry). Furthermore, top-down feedback from higher to lower visual brain areas may be weaker or absent in the peripheral visual field, as suggested by some experimental data and theoretical arguments; nevertheless humans can perceive visual inputs in the peripheral visual field arising from bottom-up V1 neural activities.
Neither model is accepted as more than an approximation. Analysis of postural sway shows much more variation than is seen in a physical pendulum or even a pair of coupled pendulums. Furthermore, quiet standing involves activity in all joints, not just the ankles or hips.In the past the variation was attributed to random effects. A more recent interpretation is that sway has a fractal structure. A fractal pattern consists of a motif repeated at varying levels of magnification. The levels are related by a ratio called the fractal dimension. It is believed that the fractal pattern offers a range of fine and gross control tuning. Fractal dimension is altered in some motor dysfunctions. In other words, the body cannot compensate well enough for imbalances. Pathology
Although standing per se is not dangerous, there are pathologies associated with it. One short term condition is orthostatic hypotension, and long term conditions are sore feet, stiff legs and low back pain. Orthostatic hypotension
Orthostatic hypotension is characterized by an unusually low blood pressure when the patient is standing up. It can cause dizziness, lightheadedness, headache, blurred or dimmed vision and fainting, because the brain does not get sufficient blood supply. This, in turn, is caused by gravity, pulling the blood into the lower part of the body. Normally, the body compensates, but in the presence of other factors, e.g. hypovolemia, diseases and medications, this response may not be sufficient. There are medications to treat hypotension. In addition, there are many lifestyle advices.