question: Do Siamese twins control one side of the body each or one head controls everything, or both have I put on both sides or something else?
comment: Long answer short, *yes*. They can be all of the above. Some twins can even share senses, like a pair of twins in Canada who can see through each other’s eyes and have conversations with eachother in their conjoined mind (A Thalamic Bridge connects their Thalami, which is how that is accomplished). Conjoined twins are quite remarkable, and offers us a totally different glimpse into how brains can function.
passages: Brain-body interaction
  
  Brain-body interactions are patterns of neural activity in the central nervous system to coordinate the activity between the brain and body. The nervous system consists of central and peripheral nervous systems and coordinates the actions of an animal by transmitting signals to and from different parts of its body. The brain and spinal cord are interwoven with the body and interact with other organ systems through the somatic, autonomic and enteric nervous systems. Neural pathways regulate brain-body interactions and allow to sense and control its body and interact with the environment.
  
  Section::::Types of interactions.
   Gonzalo Munevar has proposed an alternative explanation to demonstrate that these strange behaviors are spawned from areas in the brain and not by a dual consciousness. Two cortical areas in particular, the supplementary motor area and the premotor cortex, are crucial in the planning of executing motor tasks to external stimuli presented in the person's perceptual field. For example, a person may pick up a glass of water with his right hand and put it up to his lips for a drink. The person may have picked up the glass with his right hand, but well before this action takes place, the PMC and SMA consider a variety of different possibilities of how this action could be performed. He could have picked it up with his left hand, his mouth, even his foot! He could have done it quickly or slowly. Many possibilities are entertained, but few are actually executed. These actions are sent from the PMC to the Motor Cortex for execution. The rest are inhibited by the SMA and are not performed.
   In his 1890 essay "The Hidden Self", William James wrote of P. Janet's observations of "hysterical somnambulist" patients at Havre Hospital, detailed in Janet's 1889 Doctorate of Science thesis, "De l'Automatisme Psychologique". James made note of various aspects of automatism and the apparent multiple personalities ("two selves") of patients variously exhibiting "trances, subconscious states" or alcoholic delirium tremens. James was apparently fascinated by these manifestations and said, "How far the splitting of the mind into separate conciousnesses may obtain in each one of us is a problem. P. Janet holds that it is only possible where there is an abnormal weakness, and consequently a defect of unifying or coordinating power."
   Another important fact about the PMC is that its activation is bilateral. When it is activated, it is activated in both hemispheres of the brain. Gazzaniga observed and wrote about this phenomenon. When the corpus callosum is severed, many interhemispheric interactions are disrupted. Many areas of the brain become compromised, including the SMA. If the SMA has trouble regulating and inhibiting the actions of the PMC, it is very possible that conflicting sets of actions may be sent to the MC and performed (accounting for both hands reaching for the glass, even if only one hand is intended to grab it). It would make the appearance that there is a dual consciousness competing for dominance over the other for control of the brain, but it is not the case.
   A wide range of scientists contribute to progress on the internal model hypothesis. Michael I. Jordan, Emmanuel Todorov and 
   Section::::Possible functions.:Gender differences.
  
  A series of recent studies conducted by Yawei Cheng, using a variety of neurophysiological measures, including MEG, spinal reflex excitability, electroencephalography, have documented the presence of a gender difference in the human mirror neuron system, with female participants exhibiting stronger motor resonance than male participants.
   "Sharing" requires that the execution of a particular motor task depends on the combined actions of all the components that make up the synergy. Often, there are more components involved than are strictly needed for the particular task (see "Redundancy" below), but the control of that motor task is distributed across all components nonetheless. A simple demonstration comes from a two-finger force production task, where participants are required to generate a fixed amount of force by pushing down on two force plates with two different fingers. In this task, participants generated a particular force output by combining the contributions of independent fingers. While the force produced by any single finger can vary, this variation is constrained by the action of the other such that the desired force is always generated.
   The core elements of the bodily-kinesthetic intelligence are control of one's bodily motions and the capacity to handle objects skillfully. Gardner elaborates to say that this also includes a sense of timing, a clear sense of the goal of a physical action, along with the ability to train responses.
  
  People who have high bodily-kinesthetic intelligence should be generally good at physical activities such as sports, dance, acting, and making things.
   In addition, force entities do not have to be physically separate. A case in point is "reflexive" force dynamic constructions of the type "Chet was dragging himself instead of walking". It is perfectly possible to represent this in a Force Dynamic diagram (representing Chet’s will as the Agonist keeping the body — the Antagonist — in motion). Thus, even though Chet is one person, his will and his body are conceptualized separately.
  
  Section::::Theoretical outline.:Psychological basis.
   When presented with certain stimuli, even outside of their programmed range of experience, they responded consistently, as if they had a personality. They had their quirks and odd behaviors the way living things do. Using the only two neurons that they exhibited much of the same behaviors and oddities that any biological beings have. 
  
  Section::::Legacy.
   Section::::References in other fiction and films.:"I, Robot", 2004 Film.
  
  The robots in the 2004 film "I, Robot" (loosely based upon several of Isaac Asimov's stories) also have positronic brains. Sonny, one of the main characters from the film, has two separate positronic brains—the second being a positronic "heart"—so it has choices open to him the other robots in the film do not have. Sonny also has the possibility of being able to develop emotions and a sense of right and wrong independent of the Three Laws of Robotics; it has the ability to choose not to obey them.
   There exists significant coordination between the central pattern generators actuating individual limbs in mammals. There is both excitatory and inhibitory feedback between the left and right flexor and extensor ventral roots of a given spinal cord segment. There also exists a caudorostral excitability gradient that mediates interlimb coordination between the lumbar and cervical CPGs. This is largely single direction feedback, with the lumbar generators affecting the cervical generators, but not vice versa. This longitudinal feedback occurs both because of direct projections of lumbar neurons to cervical neurons, but also because of intermediate projections throughout the thoracic segments of the spinal cord. These thoracic segments are not simply passive elements in the network, but are rhythmically active with the lumbar generators.
   Mutually inhibitory processes are a unifying motif of all central pattern generators. This has been demonstrated in the stomatogastric (STG) nervous system of crayfish and lobsters. Two and three-cell oscillating networks based on the STG have been constructed which are amenable to mathematical analysis, and which depend in a simple way on synaptic strengths and overall activity, presumably the knobs on these things. The mathematics involved is the theory of dynamical systems.
  
  Section::::Examples.:Models of sensory-motor coupling.:Feedback and control: models of flight control in the fly.
   Isolated biological "brains", grown from cultured neurons which were originally separated, have been developed. These are not the same thing as the brains of organisms, but they have been used to control some simple robotic systems.
  
  In 2004 Thomas DeMarse and Karl Dockendorf made an "adaptive flight control with living neuronal networks on microelectrode arrays".
  
  Teams at the Georgia Institute of Technology and the University of Reading have created neurological entities integrated with a robot body. The brain receives input from sensors on the robot body and the resultant output from the brain provides the robot's only motor signals.
   In the 19th century and to a lesser extent the 20th, it was thought that each side of the brain was associated with a specific gender: the left corresponding with masculinity and the right with femininity and each half could function independently. The right side of the brain was seen as the inferior and thought to be prominent in women, savages, children, criminals, and the insane. A prime example of this in fictional literature can be seen in Robert Louis Stevenson's "Strange Case of Dr. Jekyll and Mr. Hyde".
  
  Section::::Evolutionary advantage.
   Section::::Adaptive Control theory.
  
  With the assumption that new models can be acquired and pre-existing models can be updated, the efference copy is important for the adaptive control of a movement task. Throughout the duration of a motor task, an efference copy is fed into a forward model known as a dynamics predictor whose output allows prediction of the motor output. When applying adaptive control theory techniques to motor control, efference copy is used in indirect control schemes as the input to the reference model.
  
  Section::::Scientists.
   Richard Swinburne, in his book "The Existence of God", put forward an argument for mind-body dualism based upon personal identity. He states that the brain is composed of two hemispheres and a cord linking the two and that, as modern science has shown, either of these can be removed without the person losing any memories or mental capacities.
   By contrast, the four concurrently connected galvanometers of W. Ross Ashby's Homeostat hunt, when perturbed, to converge on one of many possible stable states. Ashby used his state counting measure of variety to describe stable states and produced the "Good Regulator" theorem which requires internal models for self-organized endurance and stability (e.g. Nyquist stability criterion).
  
  Warren McCulloch proposed "Redundancy of Potential Command" as characteristic of the organization of the brain and human nervous system and the necessary condition for self-organization.
   The motor command input to the forward model can be an efference copy, as seen in Figure 1. The output from that forward model, the predicted position of the body, is then compared with the actual position of the body. The actual and predicted position of the body may differ due to noise introduced into the system by either internal (e.g. body sensors are not perfect, sensory noise) or external (e.g. unpredictable forces from outside the body) sources. If the actual and predicted body positions differ, the difference can be fed back as an input into the entire system again so that an adjusted set of motor commands can be formed to create a more accurate movement.
   The flexibility of human anatomy is a design issue for traditional "hard" robots. Several human joints such as the hips and shoulders are ball and socket joints, with the center of rotation inside the body. Since no two individuals are exactly alike, fully mimicking the degrees of freedom of a joint is not possible. Instead, the exoskeleton joint is commonly modeled as a series of hinges with one degree of freedom for each of the dominant rotations.
   An important issue for coordinating the motor system is the problem of the redundancy of motor degrees of freedom. As detailed in the "Synergies" section, many actions and movements can be executed in multiple ways because functional synergies controlling those actions are able to co-vary without changing the outcome of the action. This is possible because there are more motor components involved in the production of actions than are generally required by the physical constraints on that action. For example, the human arm has seven joints which determine the position of the hand in the world. However, only three spatial dimensions are needed to specify any location the hand could be placed in. This excess of kinematic degrees of freedom means that there are multiple arm configurations that correspond to any particular location of the hand.
   Natural History (Stuff Universe) series
  
  Quantum Gravity series
  
  Transformers Cinematic Universe
  
  Section::::Literary Universes.
  
  Section::::Literary Universes.:Natural History (Stuff) Universe.
  
  Based on M-Theory, the Unity lives in all 11 dimensions and watches our 4 dimensions for individual intelligences to entice into the Unity aggregate. It reads mental attitudes, desires, and intentions and can alter 4-D reality by action in the other 7 dimensions. While a mind is never truly lost translating into Unity, its identity is soon subsumed into the collective.
   Based on the differentiation of the left and right sides of the bodies. One side of the body stabilised while the other mobilises. Movement usually switches from one side to the other but doesn't cross the midline. In the Basic Neurocellular Patterns this relates to homolateral movement and has a strong affinity with the vertical plane."In homolateral movements we develop assymetrical movements such as crawling on our bellies and hopping on one leg, establish the vertical plane, differentiate the right side of our bodies from the left, and gain the ability to intend.The right and left sides of the body each open / close in contrast to each other, or an entire side steps as a unit in counterbalance with the entire other side, like a reptile or some mammals; often a slower traveling speed (e.g. humans "stroll" with both hands in pockets) since it is not a reaching pattern (body-half is pushing only, in locomotion with body-half the limbs traveling forward do so just from the impulse of the push, rather than a full reaching out into space).Oppositions, dichotomies, dualisms, polarities, "On the one hand, On the other hand" yes/no, do it/don’t, good/bad, correct/incorrect, simple-clear opposites (NOT complex relationships).
   The complexity of motor coordination can be seen in the task of picking up a bottle of water and pouring it in a glass. This apparently simple task is actually a combination of complex tasks that are processed at different levels. The levels of processing include: (1) for the prehension movement to the bottle, the reach and hand configuration have to be coordinated, (2) when lifting the bottle, the load and the grip force applied by the fingers need to be coordinated to account for weight, fragility, and slippage of the glass, and (3) when pouring the water from the bottle to the glass, the actions of both arms, one holding the glass and the other that is pouring the water, need to be coordinated with each other. This coordination also involves all of the eye–hand coordination processes. The brain interprets actions as spatial-temporal patterns and when each hand performs a different action simultaneously, bimanual coordination is involved. Additional levels of organization are required depending on whether the person will drink from the glass, give it to someone else, or simply put it on a table.
   and in keeping lateral balance. Within the LOPES project, it has been decided to realize this
  
  by connecting the limbs of the patient to an exoskeleton so that robot and patient move in parallel.
  
  Most gait rehabilitation robots that are currently being developed [1, 2] focus on the support of the
  
  entire gait cycle as a single unit. These robots use joint trajectories of the entire gait cycle and
  
  offer a uniform (more or less) stiff control along this trajectory. This means that the patient
  