Can humans develop new brain cells, as adults? The renewal of brain cells as has been termed neurogenesis. Scientists are divided in their opinion about this, as it is a relatively new field of investigation.
Neuroanatomists such as Santiago Ramon Cajal, believed the nervous system was a fixed system that was not capable of regeneration – but in 1962, the first evidence of adult neurogenesis was demonstrated by Joseph Altman. His findings were largely ignored by the scientific community until the 1980s, when research reignited interest in the topic by showing that neurogenesis occurs in rats and birds. Then, in the early 1990s, adult neurogenesis was also demonstrated in non-human primates and humans.
More latterly, Dr Sandrine Thuret (head of the Neurogenesis and Mental Health Laboratory at King’s College, London), with expertise in cellular, molecular, ageing and behavioral biology, has postulated that neurogenesis does indeed occur. She studies adult neurogenesis – the process of forming new brain cells in specific brain regions in adults.
Jonas Frisen of the Karolinska Institute, found that the human brain generates approximately seven hundred new neurons each day within the hippocampus. These new neurons are important for mood as well as learning and memory. Exercise and learning have also been found to improve neurogenesis. Diet is heavily linked to neurogenesis too. If you have a lot of sugar, alcohol, or animal fats in your diet, this reduces the creation of new brain cells. Omega 3 fatty acids, vitamins A, B, and E, and calorie restriction have all been found to increase neurogenesis.
Scientists have long known that the hippocampus is essential for learning, emotion, mood and memory. Thuret’s work concentrates on the hippocampus, which is a grey structure within the middle of the brain. Dr Thuret says:
“While 700 neurons per day may not appear to be much when compared to the several billions of neurons within the human brain, by the time you clock age fifty, you would have exchanged all the neurons you were born with within the brain with adult generated neurons.”
Take a look at this presentation that affects us all, and judge for yourself.