hippocampus Archives

Neurogenesis and a Healthy Brain — Medical Illustration of the Hippocampus

The human brain is a remarkable organ, capable of many things at once. While it automatically controls all of your body’s functions, it also lets you read and process this article. Our brains can be damaged by strokes, malignancies, accidents, Alzheimer’s, and many other factors. Wouldn’t it be wonderful to have neurogenesis, where our brains could generate new neurons to replace damaged ones?

Many scientists have debated whether adult brains can generate new neurons. Neurons develop in the womb and, to a certain extent, during childhood and adolescence. But many thought that, after maturity, we didn’t develop new neurons, even though adult brains do form new connections between neurons and remove those that are no longer necessary.

For seven years, molecular biologist Ionut Dumitru at the Karolinska Institute in Sweden has been looking for evidence of neurogenesis in adult brains. Recent research by Dumitru’s team provides strong evidence that it does occur in the adult brain’s hippocampus, a region essential to learning and memory. Earlier research showed neurogenesis in the brains of laboratory rats, but it is unethical to experiment on the brain of a living person. Dumitru and his colleagues analyzed brain cells from the hippocampi of people who had died at various ages of life. Their analysis showed that active neurogenesis occurs in the adult hippocampus. Scientists knew that hippocampal neurons could reorganize and form new connections, helping us take in new information. But this research indicates that the hippocampus may also generate new neurons.

What is the key to keeping a healthy brain? Our brains can benefit from enriching activities like socializing, being involved in a church, and learning new skills. Thinking can be tiring, and it’s hard to make the effort when artificial intelligence (AI) can automate many tasks that require deep thought. Mental challenges like reading, writing, solving puzzles, playing chess, and practicing active listening can benefit your brain health.

Physical exercise also boosts brain health and perhaps neurogenesis. Physical exercise and mental exercise through critical thinking can help keep you sharp. Even when it is easier to avoid exercise, decision-making, or reflecting on the important questions in life, do it anyway. Your body and your brain will benefit, and so can your faith. Consider the evidence for God’s existence. Study the Bible, meditate on it, and apply it to your life. It may be difficult, but it can improve your mental outlook and psychological perspective. Knowing the evidence for God’s existence and the Bible’s reliability can help you to “always be prepared to give an answer to everyone who asks you to give the reason for the hope that you have” (1 Peter 3:15). We pray that our posts and printed materials will help you do that.

References: newscientist.com and insideh o ok.com

Majesty In Miniature

“Majesty in Miniature” is the title of an interesting article in the July 2017 issue of National Geographic (pages 99-118). The article is about the amazing hummingbirds.

Scientists have had a hard time getting data as they try to understand how hummingbirds do what they do. The birds fly at speeds up to 35 mph (56 kph) and they have a “reverse gear.” Their metabolic rate is the highest of any vertebrate on the planet. For every minute they are in flight, they drink more than 12 ounces (355 ml) of water. They consume more than their body weight of nectar every day. Their tongues lap up to 15 times a second. Proportionally their brain is one of the largest in the animal kingdom making up 4.2% of their body weight. It is only with the advent of high-speed cameras and advanced wind tunnels that some of the mysteries of the majesty in miniature have been answered.

Hummingbird brains have a large hippocampus which allows them to remember locations. Their brain has a large lentiformis mesencephali motion sensor which gives the bird stabilization when flying. It has a small arm wing which allows wrist motion to control a larger area of the wing leading to a more powerful upstroke. When a hummingbird hovers, it rotates its wings between the upstrokes and the downstrokes making a figure eight motion. This motion creates vortexes that allow both the downstroke and the upstroke to provide lift. Birds such as pigeons push down to propel forward, but there is no lift in the upstroke. The design of the hummingbird wing gives it the unique ability to get lift out of both strokes.

The design of all of these features defies any chance explanation. Nearly everything the hummingbird does is unique to that species. We don’t see birds with some of these characteristics, and yet all of them are essential to the hummingbird’s survival. Indeed this bird is majesty in miniature, and a testimony to God’s wisdom and design. He has equipped all creatures to live in their particular, unique environment.
–John N. Clayton © 2017