Are neurological disorders the result of brain evolution mistakes?

July 24, 2018 by Bob Yirka, Medical Xpress report
Credit: CC0 Public Domain

A team of researchers affiliated with several institutions in Australia has proposed that some neurological disorders might have their roots in evolutionary mistakes. In their paper published in the journal Nature Neuroscience, the group describes their ideas and possible paths of research moving forward.

As scientists delve ever deeper into our brains as part of an effort to understand how they work, they are proposing new ideas to explain their observations. One big area of research involves neurological disorders such as schizophrenia. How do they come about, what happens, and are there ways to treat them? In this new effort, the researchers have proposed a new idea—that some neurological disorders might result from natural evolution. They note that evolution of the brain is a balancing act due to its physical nature. We only have so much wiring, because our skulls are of a certain size. Thus, as our brains evolve, costs of anatomical wiring are weighed against computational gains as measured by an increase in complexity. They further suggest that due to a limited means for increasing the amount of wiring, nature is forced to deal with how to increase complexity. They propose that such a is likely to result sometimes in evolutionary changes that do not pan out—in other words, errors. And some of these errors are likely to take the form of neurological disorders such as schizophrenia.

As part of their idea, they note that current theory suggests that the brain has connectomes—regions of the brain that are connected in certain ways for certain purposes. As arise due to environmental or other factors, causing mutations, connectomes can change or become disrupted. Such changes, they note, are likely to be seen by modern testing devices as changes to —this is because of the role gray matter plays in routing communications in the brain.

To better understand what sort of changes we might see in grey matter due to evolutionary mutations, the group created a mathematical model to simulate such changes. They found changes in grey matter that were sometimes consistent with similar changes that have been reported in .

The researchers suggest their ideas open the door to two new lines of research. The first would involve study of communication hubs in the and the way they evolve. The second would be focused on using what is learned in such research efforts to treat those with neurological .

Explore further: Researchers find brain network link between development, aging and brain disease

More information: Leonardo L. Gollo et al. Fragility and volatility of structural hubs in the human connectome, Nature Neuroscience (2018). DOI: 10.1038/s41593-018-0188-z

Brain structure reflects the influence of evolutionary processes that pit the costs of its anatomical wiring against the computational advantages conferred by its complexity. We show that cost-neutral 'mutations' of the human connectome almost inevitably degrade its complexity and disconnect high-strength connections to prefrontal network hubs. Conversely, restoring the peripheral location and strong connectivity of empirically observed hubs confers a wiring cost that the brain appears to minimize. Progressive cost-neutral randomization yields daughter networks that differ substantially from one another and results in a topologically unstable phenomenon consistent with a phase transition in complex systems. The fragility of hubs to disconnection shows a significant association with the acceleration of gray matter loss in schizophrenia. Together with effects on wiring cost, we suggest that fragile prefrontal hub connections and topological volatility act as evolutionary influences on brain networks whose optimal set point may be perturbed in neuropsychiatric disorders.

Related Stories

Researchers find brain network link between development, aging and brain disease

November 25, 2014
(Medical Xpress)—A team of bio-researchers with members from across Europe has found evidence that suggests that grey matter development early in life tends to be the first to regress later in life—related findings also ...

The brains of people with schizophrenia may attempt to heal from the disease

August 8, 2012
(Medical Xpress) -- New NeuRA research shows that the brains of people with schizophrenia may attempt to repair damage caused by the disease, in another example of the adult brain’s capacity to change and grow.

Genetic analysis finds rare, damaging variants contribute to the risk of schizophrenia

June 27, 2017
(Medical Xpress)—Via genetic analysis, a large international team of researchers has found rare, damaging gene variants that they believe contribute to the risk of a person developing schizophrenia. In their paper published ...

Study finds possibility of new ways to treat, manage epilepsy seizures

May 7, 2018
New findings from the University of Kentucky published in the Journal of Neuroscience demonstrate that there may be ways to address blood-brain barrier dysfunction in epilepsy.

Even brief maternal deprivation early in life alters adult brain function and cognition

May 3, 2018
When a baby is taken from its mother for even a brief period early in life, this traumatic event significantly alters the future, adult function of the brain, according to a new animal model study from the School of Science ...

Rare mutations found to increase risk of schizophrenia and shortened school stays

October 4, 2016
(Medical Xpress)—Two teams of researchers looking to better understand what happens to people born with certain rare genetic mutations have found a link between an increased risk of schizophrenia and how long such people ...

Recommended for you

Regulating microglial activity may reduce inflammation in neurodegenerative diseases

October 17, 2018
A group of Massachusetts General Hospital (MGH) investigators is proposing that targeting immune checkpoints—molecules that regulate the activity of the immune system—in immune cells called microglia could reduce the ...

New imaging tool captures how sound moves through the chinchilla ear

October 17, 2018
Researchers have developed a new device that can be used to visualize how sound-induced vibrations travel through the ear. The technology is providing new insight into how the ear receives and processes sound waves and, with ...

Sensory perception is not a one-way street

October 17, 2018
When we interact with the world, such as when we reach out to touch an object, the brain actively changes incoming sensory signals based on anticipation. This so-called 'sensory gating' has now been investigated by neuroscientists ...

Environmental factors may trigger onset of multiple sclerosis

October 16, 2018
A new Tel Aviv University study finds that certain environmental conditions may precipitate structural changes that take place in myelin sheaths in the onset of multiple sclerosis (MS). Myelin sheaths are the "insulating ...

Study points to possible new therapy for hearing loss

October 15, 2018
Researchers have taken an important step toward what may become a new approach to restore hearing loss. In a new study, out today in the European Journal of Neuroscience, scientists have been able to regrow the sensory hair ...

Scientists examine how neuropathic pain responds to Metformin

October 15, 2018
Scientists seeking an effective treatment for one type of chronic pain believe a ubiquitous, generic diabetes medication might solve both the discomfort and the mental deficits that go with the pain.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.