The "positive current of injury" is taken from Robert Becker, M.D.'s book The Body Electric. In this important book, Becker details his discovery of the subtle DC electrical system in the meningeal-perineural tissue previously considered only protective and without other function.
Becker discovered that this meningeal-perineural tissue and its DC electricity was necessary for neuron function and that without it the neuron dies.
Becker further identified this system's polarity structure and observed that a bone fracture disrupted the polarity causing a positive current to establish in what normally would be a negative field.
It is the relatively positive current at the site of injury that activates an inflammatory reaction and initiates the body's self-healing process. It is this process - the body's self-healing process - which acts to normalize all currents of injury, whether large or small.
Positive currents of injury distract from the body-mind's full potential. Healing injury takes metabolic energy, uses raw materials, and causes adaptive modifications in the secondary energy system of meridians.
Becker called the meningeal-perineural DC a "primitive analog system" without which the neuron does not function.
Becker observed (in frogs and extrapolated to humans here) that the polarity of efferent, motor nerves is opposite that of afferent, sensory nerves, but that the net polarity is efferent dominant.
That is, measuring the current in an extremity, for example, one finds that the shoulder is more electro-positive than the elbow which is more electro-positive than the wrist, even though there also is a sensory current polarized in the opposite direction in that extremity.
Imagining all the nerve cells in all the tissues and knowing that every millimeter of every nerve cell is covered with meningeal-perineural tissue, which is the conductor of a polarized direct current, one begins to understand the importance of this system.
Because, as in the example above, the shoulder has an electrical value quantitatively different from the elbow and wrist, we begin to understand the formal structure of this system as an analog system. Every location on the body has a specific electrical identity. Injury disturbs that specific electrical identity.
We know that all current-carrying conductors radiate an electromagnetic field whether it's the copper wire supplying electricity to a light bulb or the subtle DC in the human body's meningeal-perineural system.
In the human body, this radiant electromagnetic field is sensitive to other fields in its environment and may be responsible for what some describe as intuition or a 6th sense.
Introducing a positive current to this field, as in the case of a wrist watch or cell phone battery, initiates the body's healing response. However, though the body will try to heal the injury represented by the battery, it never can as long as the battery is in the body's electromagnetic field.