How does the birth of new neurons in the adult brain help cognition, even if the brain can make new neurons in the adult version?
The brain cells that control its operation are the same ones you will always have, and you are born with most of the neurons you have. Some areas of the brain continue to produce new neurons during adulthood, albeit at a much slower rate. However, scientists are unsure whether this process actually occurs in adults and what role it plays in the brain.
Research has suggested that individuals with epilepsy, Alzheimer’s disease and other dementias have fewer neurons in their later years than those without the condition. However, it is unclear whether a lack of new neurons is responsible for cognitive difficulties in these individuals.
A team of researchers including stem cell researchers, neuroscientists, neurologists, neurosurgeons and neuropsychologists have conducted research that establishes a link between the creation of new neurons in adults and the acquisition of knowledge through listening.
The development of new neurons and the onset of learning.
The importance of new neurons in memory and learning in mice has been acknowledged by scientists, but the difficulty of identifying and analyzing them in the adult brain, as well as their rarity, has made scientists skeptical about their importance in human brain function.
We investigated the effects of neurogenesis in adults, by studying the brains of patients with drug-resistant epilepsy who underwent cognitive assessments before and after surgery, and who had already received treatment to treat their seizures.
A relationship was found between the presence of new neurons in the adult brain and a decrease in cognitive decline, particularly in the areas of verbal and auditory learning.
We were surprised by this fact. While it is well known that mice learn by exploring new places and by exploring unfamiliar environments with visual aid, it was not found that this relationship existed in humans with new neurons.
Promoting a brighter outlook.
In their daily lives, it is necessary for many people to continue communicating and remembering conversations, although this process becomes less important as people age; Neurological disorders make this effect more severe than similar age patterns, and the greater the cognitive decline in the population, the greater the consequences for health care systems around the world.
The relationship between newborn neurons and verbal learning could be the basis for developing treatments that restore cognition in humans. Furthermore, improving new neuron generation could lead to improved brain health and restoration of cognition in individuals with epilepsy or dementia. However, these ideas can only be achieved over time.
Our observation that new neurons work differently in both humans and mice highlights the critical need to investigate biological functions such as neurogenesis in humans whenever possible. This would allow research conducted in animal models such as mice to be applied to people and potentially lead to successful treatments.
The primary purpose of modern epilepsy medications is to reduce seizures, but many treatments do not address the cognitive decline that accompanies patients with epilepsy. To improve cognitive outcomes, we launched a clinical trial that aims to use aerobic exercise to enhance new neuron production and cognition in patients.
We are currently in the early Phase 1 of this trial, and we want to determine whether the study is safe. Currently, two patients have safely completed the study.