SCIENTIFIC AMERICAN / MARCH 2015 / by Caitlin Murray


TNF - tumor necrosis factor, inflammatory molecule - a type of cytokin / neurological reflexes (predictable responses to sensory stimuli) block the prevention of TNF / the use of nerve-stimulating electronic devices to treat inflammation and reverse disability is laying the foundation for a new discipline called bioelectronic medicine

the reflex circuit - stimuli > sensory neurons > interneurons > motor neurons > the subsequent firing of the motor neurons sends the electrical signal back to the body's muscles and organs triggering behaviors / reflexes coordinate the bodies behaviors

how do electrical signals that course through motor neurons actually control organ function? through neurotransmitters - molecules that interact with receptors (like drugs - many drugs selectively bind to specific receptors that modify metabolic activity and turn on genes in selected cells - but they have side effects) / using a device to send signals down a nerve to stimulate production of drugs like neurotransmitters offers a distinct advantage - the body's self-made drugs deliver chemicals to specific tissues in precise, nontoxic amounts at just the right time, diminishing the occurrence of side effects

CNI-1493 (Semapimod) - an experimental drug, which injected into the brain prevented TNF production during a stroke (cerebral infarction), but it also blocked TNF production in organs throughout the body

Perhaps, the motor neurons exiting the brain carried electrical signals to inhibit TNF in the rest of the body

Much of what is known about neural control of behavior originated from early studies of stroke patients with localized brain damage > Paul Broca (1824-1880) observed that damage to a small region in the left posterior frontal cortex resulted in the inability to speak while preserving language comprehension (expressive aphasia) > Carl Wernicke (1848 - 1905) noted that stroke damage in a nearby area produced sensory aphasia, an incapacity to either understand or produce meaningful speech > therefore, cutting the individual circuits that connect the brain and organs could reveal the specific nerves that control TNF

Linda Watkins (UC Boulder) study of the vagus nerve - has a major role in transmitting sensory information from the body's organs into the base of the brain - proposition that the TNF "off" signal from the vagus nerve completes a reflex nerve circuit between the brain and the immune system

Hypothesis: that reflex neural circuits controlling immunity would maintain health-promoting processes - as opposed to disease-triggering inflammation - by preventing the toxic release of TNF and other inflammatory signaling molecules (previous immunological studies has focused on the role of the immune system in protecting the body independent of the nervous system. Immunity, in these accounts, centered on the workings of lymphocytes, monocytes, macrophages and other white blood cells, but not neurons) / THE INFLAMMATORY REFLEX - keeps the immune system from becoming overactive or underactive - when it does not function well, autoimmune diseases appear

Experiments: found that an intact vagus nerve was required for CNI-1493 in the brain to switch off TNG production by immune cells in various organs - the nerve had to be intact in its entire trajectory

the creation of vagus nerve stimulators - currently in experiments for rheumatoid arthritis and IBS

In higher vertebrates, the two biological systems that learn from experience to defend an organism are the nervous and immune systems. Discovery of the inflammatory reflex revealed that these two main systems intersect in simple, precise reflex circuits to maintain immunological homeostasis.


All perception used to be proximal - by contact or sensed differences in concentration or pressure waves - perception and action evolved together, driving most of the basic diversification of the tree of life that exists today > metaphor for the spread of digital technology: Although advances in communications technology have transformed our world many times in the past - the invention of writing signaled the end of prehistory; the printing press sent waves of change through all the major institutions of society - digital technology could have a greater impact than anything that has come before. It will enhance the powers of some individuals and organizations while subverting the powers of others, creating both opportunities and risks that could scarcely have been imagined a generation ago.

TRANSPARENCY: governments, armies, churches, universities, banks and companies - evolved in an environment in which most knowledge was local and secrets were easily kept - as with evolution - these organizations find themselves exposed to daylight and must respond to new transparency - US supreme court justice Louis D. Brandeis - "sunlight is said to be the best of disinfectants"

a pro-power article: "But in spite of much political rhetoric about the unalloyed virtues of transparency, secrecy in the halls of power is still maintained - and for good reason. . . As optimists, we would like to believe that this period of turmoil will push us toward organizations better aligned with the moral codes of civil society and powerful novel ways to correct deviant organizational behavior. But we cannot rule out a permanent weakening of our intelligence organizations that will reduce their abilities to identify threats."