Newer research and a better understanding of brain circuitry has revealed a much more complex explanation – one that sufferers are likely to find far more validating. We now understand that a wide range of symptoms can be produced by biologically based abnormalities in the function, rather than the structure, of the brain. You might think of this as a problem of “software” rather than “hardware.” Software, or functional, changes in the brain can have many real impacts on the body’s hormonal, metabolic and immune-system functioning.
Neuroscientists now understand that the brain is essentially a prediction machine. To efficiently process a flood of incoming information, the brain makes predictions about what it thinks this information is going to tell it based on expectations and assumptions. Most of the time these are accurate guesses, but the cost of such an efficient system is that sometimes the brain gets it wrong. This is what creates the “magic” of optical illusions, and it also underlies the placebo effect (the real phenomenon of positive expectations leading to symptom improvement) and its counterpart, the nocebo effect (the onset of new, or worsening, symptoms in the wake of negative expectations).