|
|
 |
|
| Michele Ernandes |
 |
Istituto di Fisiologia e Nutrizione umana, via Augusto ELIA n°3, 90127 PALERMO
e-mail: ernandes@unipa.it |
Poster Presentation: |
|
| Integrating triune brain's functions: role of serotonin system. |
| M. Ernandes, M. La Guardia, M. Giammanco, M. A. Cascio, M. Cecconi, D. Di Majo, G. Indelicato & G. Tabacchi | |
|
| According to MacLean's Triune Concept of the Brain, the human brain is described as formed by three principal phylogenetic structures that have been superimposed and that have become integrated during evolution. These three basic types are termed as Protoreptilian (R-complex), Paleomammalian (Limbic System) and Neomammalian (Neo cortex). The counterpart of R-complex in mammals is fundamental for genetically constituted forms of behaviours as establishing territory, engaging in various types of display, hunting, mating, imprinting, forming social hierarchies, and selecting leaders: the main site for these behaviours is formed by basal ganglia. The Limbic System acts as a regulator of the R-complex, while the Neomammalian brain is the seat of self consciousness, of space and time conceptions, and of causality and constancy. These three basic brains must intermesh and function together as a Triune Brain. The serotonin one provides the most powerful system of integration, among the three basic brain types, identified till now. Neuronal synthesis of serotonin depends on the plasma \"trp/Large Neutral Amino Acids\" ratio, because of competition made by LNAAs against tryptophan for neuron access, since they use the same carrier to cross the blood-brain barrier. \"Trp/LNAAs\" ratio value, in turn, tends to be correlated with amino acid composition of the diet: So a low \"trp/LNAAs\" ratio diet lowers brain serotonin synthesis. Serotonin deficiency involves several behavioural consequences such as tendency towards aggressive behaviour, increase of intraspecific competition, increase of magic thought (i. e. obsessive-compulsive disorder) or religious fanaticism, temporal lobe epilepsy, and attraction for fire. Most of these behavioural alterations may be due to a lowered integration among the three basic brains, and/or to a disruption of the inhibitory control exerted by Limbic System on basal ganglia (R-complex). Among cereals utilised for human feeding, maize has a very low \"trp/LNAAs\" value, and this may led to a brain serotonin deficiency. We have experimentally found that rats maize nourished became mouse-killers, and that they were serotonin deficiency rats. Among humans it has been observed that countries above the median in maize consumption have significantly higher homicide rates than countries below the median. Maize was firstly and largely utilised by Native American peoples. Among them, above-mentioned behavioural consequences appear, as a rule, positively correlated with maize alimentary dependence. Particularly, Aztecs may constitute a reference pattern of serotonin deficiency due to alimentary causes. Neuro-behavioural after-effects of dietary low \"trp/LNAAs\" values are thinkable for some African or European peoples, today or in the past. We think that a low dietary \"trp/LNAAs\" value might constitute a favourable background for the setting of fanatical ideologies, and a risk factor towards violence or intolerance on the occasion of conflicts caused by various motives. |
|
|
 |
|
|
|
