Theory versus biological facts: Mental modules and models for behavior

In a model combining the measurement of data coming from many individual nerve cells with sophisticated optical, genetic and electrophysiological techniques, olfactory bulb neurons extract relevant information from multi-sensory input. (Blumhagen et al., in press) recently showed that neurons in the zebrafish cortex use a filter to tune in specifically on those parts of neuronal conversations that allow the precise identity of an odor.

Nerve cells in other brain areas apply other filters. It is now more certain the vertebrate brain uses sophisticated arrays of similar filters to ensure that all neurons receive appropriate messages. These sophisticated arrays of filters appear to play an important role in the perception and memory of odors and other stimuli. ~ adapted from Neuronal filters for broadband information transmission in the brain.

Perception and memory are functions of messaging among neurons in the brain’s neural networks, which are linked to hormones and behavior.  However, compared to messages delivered directly to the olfactory bulb, non-olfactory/pheromonal sensory stimuli from the environment of animal species does not appear to directly activate any hormone response associated with behavior. This absence of direct linkage indicates that the sophisticated arrays of filters suspected to be important to the perception and memory of other stimuli, are less important to behavior than is the filtering by the olfactory bulb.

If “mental modules” evolved to become more important to human behavior than is the direct link from odors to the olfactory bulb in the mammalian brain, a “mental module” associated with visual input might have evolved to become more important to human behavior than is the pathway from olfactory input to gene activation in cells of tissue in the organ of the organ system most important to human behavior (i.e., the brain). If not, the “mental modules” theory can only be another misleading misrepresentation of biological facts.

If, as it appears to be, the “mental modules” theory is simply another joke originating from cartoon Darwinists, evolutionary theorists who do not get the joke will continue to promote the “mental modules” theory as one that is important to the understanding of evolved human behaviors. Others who understand the difference between theory and biological facts linked to the evolution of human behavior can continue to laugh at the silly evolutionary theorists until all funding for their ridiculous theories is eliminated from grant consideration. Then we can cry with them, if we have evolved a “mental module” either for sympathy, or empathy, that is.

I have not yet read the manuscript, however, and it may indicate something not indicated in the news version, which might somehow support the evolutionary theory of “mental modules.” This is, however, altogether unlikely, and I wanted to post this notice to my blog in case others are interested in following up on the latest information available from scientists.

Blumhagen, F., Zhu, P., Shum, J., Scharer, Y.-P. Z., Yaksi, E., Deisseroth, K., et al. (in press). Neuronal filtering of multiplexed odour representations. Nature, advance online publication.


Author: James Kohl