Here is a rather new evolutionary theory about cognition that can be found at this website.
RG: How could a feature that causes psychiatric disease be an evolutionary advantage?
Kingsley: Several studies suggest that the same genes that have led to rapid increase in cognitive abilities in humans may have also increased our susceptibility to psychiatric disease. This may seem paradoxical, but it clearly applies to other systems in the body. For example, humans are one of the few mammals that have evolved the ability to walk regularly on two legs. This new mode of locomotion frees up our hands for manipulating objects and using tools. However, our recent evolutionary transition to walking upright has also brought with it a high incidence of lower back and knee problems in humans. Similarly, rapid expansion of brain size and cognitive abilities in humans has been a key feature of our evolutionary success. But, the very genomic changes that underlie recent brain changes also may increase our susceptibility to some psychiatric diseases.
Our study provides a specific example of how this could happen by expanding a particular regulatory DNA sequence inside a key gene controlling neural activity. The same structural change that produces this genomic feature also generates a tandem array that is prone to further variation and may increase the risk of some common psychiatric diseases.
The theory of Kingsley and his co-authors is that the evolutionary advantage that came with improvements in cognition also came with the significant costs of susceptibility to psychiatric diseases such as bipolar disorder and schizophrenia.
My (controversial) extrapolation from Kingsley’s quote would be that evolution of human cognition may not only have come with a propensity for psychiatric diseases, but also with a propensity for an unjustified certainty in religious thinking. In other words, certainty and rigidity of religious thinking may be a side effect (or weakness) of the evolution of cognition. Similarly, kundalini and grandiose delusions may be a side effect (or weakness) of the evolution of cognition.
Other controversial statements about the association between religion and psychiatric disease can be found at Wikipedia and at a Scientific American blog site.
In a previous blog post, I suggested that evolution did not prepare humans for spending prolonged time in meditation and/or spiritual-type thinking. However, it might be more accurate to say that human’s maladaptation to spiritual pursuits is a result of the great evolutionary advances of cognition.