Un articol din SciAm ne spune ca bacteriile care ne colonizeaza influenteaza dezvoltarea creieirului si personalitatea. Sa fie oare asta explicatia mamaligii care nu explodeaza si a fricii romanilor de a calatori?

Amu, eu am mai scris in trecut despre toxoplasma si presupusul efect asupra psihologiei nationale, atat pe blog cat si pe twitter. Asa ca am frematat cand am dat peste un articol despre un studiu care atribuie bacteriilor intestinale un rol important in formarea personalitatii.

Ce zice articolul? Incepe cu some Theoretical background:

Scientists have long recognized that the bacterial cells inhabiting our skin and gut outnumber human cells by ten-to-one. (..) Moreover, these bacteria have been implicated in the development of neurological and behavioral disorders. For example, gut bacteria may have an influence on the body’s use of vitamin B6, which in turn has profound effects on the health of nerve and muscle cells. They modulate immune tolerance and, because of this, they may have an influence on autoimmune diseases, such as multiple sclerosis. They have been shown to influence anxiety-related behavior, although there is controversy regarding whether gut bacteria exacerbate or ameliorate stress related anxiety responses. In autism and other pervasive developmental disorders, there are reports that the specific bacterial species present in the gut are altered and that gastrointestinal problems exacerbate behavioral symptoms. A newly developed biochemical test for autism is based, in part, upon the end products of bacterial metabolism.

Si testul propriu-zis:

The scientists raised mice lacking normal gut microflora, then compared their behavior, brain chemistry and brain development to mice having normal gut bacteria. The microbe-free animals were more active and, in specific behavioral tests, were less anxious than microbe-colonized mice. In one test of anxiety, animals were given the choice of staying in the relative safety of a dark box, or of venturing into a lighted box. Bacteria-free animals spent significantly more time in the light box than their bacterially colonized littermates. Similarly, in another test of anxiety, animals were given the choice of venturing out on an elevated and unprotected bar to explore their environment, or remain in the relative safety of a similar bar protected by enclosing walls. Once again, the microbe-free animals proved themselves bolder than their colonized kin. (..) there is a critical period in the development of the brain when the bacteria are influential.

Intra si Vagus nerve in jocul ipotezelor:

the Vagus nerve, for example, connects the gut to the brain, and it’s known that infection with the Salmonella bacteria stimulates the expression of certain genes in the brain, which is blocked when the Vagus nerve is severed. This nerve may be stimulated as well by normal gut microbes, and serve as the link between them and the brain.

Ce treaba are articolul cu Romania si romanii?

Un bun indicator al nivelului de igiena si al asaltului bacterian la care sunt supusi nou-nascutii unei tari este mortalitatea infantila, unde Romania ocupa locul 77 in lume, dupa tari precum Jamaica, Ucraina, Guyana Franceza, Trinidad-Tobago, Tailanda, Sri Lanka, Cipru etc – noroc cu Moldova si Albania ca am fi fost iar ultimii in Europa (dar oricum suntem ultimii in EU). Imi pare asadar ca romanii sunt mai asemanatori cu sobolanii care nu indrazneau sa iasa din cutie sa exploreze fiindca nu-i lasau bacteriile

Poate asta-i si motivul pentru care calatoritul e-o placere “burgheza” (cu exceptia calatoriilor in container). One more dent in the freewill conspiracy.

Sources / More info: SciAm, twt, wiki-vagus, wiki-imr, pnas-gut, [emotions] [evolution] [gut feelings] [money] [uncertainty] [decisive] [chabris] [paulson]