====== Body Model ======

As discussed in [[0main]], all mental processing of reality depends on creation of mental models, rather than some sort of direct apprehension of reality ([[naive_realism]].)  More familiar examples of this relate to visual perception, such as of color, but this is equally true of all perceptible aspects of our body: our pose, our motion, touch sensation, etc.  

The generation of conscious perceptions is almost an incidental aspect of the body model, which is a crucial part of the unconscious [[wp>Control_theory | control system]] we use to regulate our movement.  This control depends on an [[wp>Internal model]] of our body's behavior as a [[wp>Dynamical system]].  Although we directly sense our body pose and motion through [[wp>Proprioception]] and vision, controlled motion relies to a large degree on [[wp>Feed-forward]] control using a predictive model (analogous to the [[wp>Kalman filter]]) that estimates body motion by fusing sensory feedback information with the expected sensory response to the last motion command (the [[wp>Efference copy]].)  Because of this feedback relation, body model is tightly integrated with [[action]].

This ability to control our body [[wp>Motor learning | is learned]], but the result of this learning is fundamentally unconscious [[wp>Procedural memory]] that we can only access as a demonstrated (or visualized) motion.  While we can describe the motion that must be done, the only way to learn is to practice making the motion, training body model and [[action]] to work together with smooth coordination.  See [[representational_opacity]].

Our tendency to [[wp>Motor imagery | visualize motion in an embodied manner]] gives evidence that the body model can operate in relative independence from actual motion, however the most dramatic demonstration of the fundamental autonomy of the body model from the actual body is the phenomenon of [[wp>Phantom_limb| phantom limbs]], where the perception of an existing, functioning, feeling limb persists even after the limb is gone.  [[books:phantoms_in_brain]] discusses phantom limbs at length, and also other puzzling aspects of body model, such as the relative ease with which our body model extends outside ourselves in the [[http://www.newscientist.com/article/dn16809-body-illusions-rubber-hand-illusion.html|rubber-hand illusion]].

In the [[analysis:level_map]], the body model is shown to be in two-way communication with [[analysis:emotion:0main]] and the [[analysis:level_map#viscera]].  Our emotions influence our internal body state, and our perception of this "gut feeling" influences our emotion.  Regulation of the [[wp>Milieu_intérieur|interior milieu]] to implement [[analysis:physical:homeostasis]] can be considered an aspect of the body model.  

This mind/body connection is well established by science, and the effectiveness of manipulating the mind to affect the body or of manipulating the body to affect the mind has been [[wp>Bodymind | exploited in alternative therapies]], but the lack of appreciation for how this connection is mediated by the body model has led some to suppose that mind is somehow actually implemented in the body as a whole, and to look for examples of information processing outside the brain (such as in the [[wp>Enteric nervous system]].)  This is an example of [[analysis:philosophy:level_confusion]].
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{{tag>mind neuro body perception emotion representation reality}}