A new study by researchers at McMaster University in Hamilton, Ontario now suggests that gut bacteria may also influence behaviour and cognitive processes such as memory by exerting an effect on gene activity during brain development.
Yet another example of how forces beyond our control shape our consciousness. And another example of how powerful the most minute changes can have startling effects on our personalities and behaviors.
Bacteria colonize the gut in the days following birth, during a sensitive period of brain development, and apparently influence behaviour by inducing changes in the expression of certain genes.
The experiment was conducted on mice, which gives us a strong hint that the effect is similar in humans. Mice lacking certain gut bacteria were found to have specific differences in the expression of three genes, each of which is associated with stress and emotional behaviors and feelings:
Brain-derived neurotrophic factor (BDNF) was significantly up-regulated, and the 5HT1A serotonin receptor sub-type down-regulated, in the dentate gyrus of the hippocampus. The gene encoding the NR2B subunit of the NMDA receptor was also down-regulated in the amygdala.
This fits squarely into the model of human cognition and “personality” that defies the Christian “Free Will” dogma. Simply put, what we think of as our freedom of choice is highly limited, almost exclusively by factors beyond any human control. By the time I perceive a choice, there have been hundreds, or thousands, or perhaps hundreds of thousands of environmental factors at work, each shaping my brain in ways that will alter my conscious perceptions. My “choice” is better described as a “result” of accumulated data being fed through this “environmental algorithm” expressed as my brain.
While this has complicated implications for human interactions (how do we treat mental illness? criminals? the poor? etc..) it’s quite clear how it impacts the notion of the Christian god. He either lied or was mistaken about the “gift of free will.” We humans are not free to choose any option in any situation. Rather, we are bound by the constraints of our environment and our “brain algorithms,” and we literally are incapable of seeing things any way besides the way we see them.
In other words, we don’t have the kind of free will that would make the Jesus/heaven/hell doctrine sensible.