The Adaptivity of the Human Brain: Neuroplasticity

Recent research from the DZNE University of Magdeburg, along with the Hertie Institute for Clinical Brain Research at the University of Tübingen, has determined that the human brain ages in layers. Specifically in the area of the cerebral cortex, which is responsible for tactile sensation, the human brain ages less. The cerebral cortex itself is made up of multiple folds and is only a few millimeters thick. As the cerebral cortex ages, the delicate tissue becomes susceptible to wear and tear and begins to thin. Aside from the loss of neurons in the brain, the thinning tissue is one of the main components that scientists attribute to the aging brain.

According to neuroscientist and professor Esther Kühn, “it is generally assumed that less brain volume means reduced function. However, little is known about how exactly the cortex actually ages… [which] is remarkable, given that many of our daily activities depend on a functioning cortex.”

Kühn and her colleagues sought to examine the function of the cerebral cortex, utilizing high-resolution MRI brain scans of young adults, old adults, and mice. The main focus of their study was the “primary somatosensory cortex,” found on the left and right sides of the head near the ear. The primary somatosensory cortex is the area of the brain that controls perception and interaction with the external environment. Examples include grasping an object, picking up and putting down an object, and other essential movements. Kühn explains that humans “constantly need haptic feedback to control movements [because] the corresponding stimuli converge in this area are also processed here.”

This breakthrough in brain aging is significant in understanding the way human beings process information. Functional MRI scans were able to take images of where the signals are actually received in the cortex’s middle layer. According to the researchers’ findings, the middle layer and areas above it were exceptionally resistant to aging. The upper layers were noted to facilitate communication between the fingers, which is relevant to the ability to grasp objects. Myelin, which helps transmit nerve signals, was found to be different depending on the layer observed. The deeper layers showed age-related degeneration and were thinner in the older participants of the study. Interestingly, the myelin content of these layers increased with age, which is believed to be caused by an increase in the amount of neurons that affect the nerve impulses and “sharpen the signal.” One of the participants of the study was a 52

year-old male, born with a missing limb, who had to rely on one arm; in the review of his cerebral cortex, the middle layer, which would receive sensory inputs, was significantly thinner in comparison to other layers.

There is no wonder medical professionals are amazed by the discovery of neuroplasticity. For centuries, physical impairments were seen to have solely negative effects on the body at large. The phenomenon of the brain compensating for physical deficits in other parts of the body provides doctors with groundbreaking insights about human resilience.

Kühn pointed out that through their findings, researchers can see “an indication that the brain preserves what is used intensively… a feature of neuroplasticity,” or the adaptability of the brain. She continued to describe this by explaining that “sensorimotor skills that are repeatedly practiced, such as typing on a keyboard, can remain stable for a long time, even in old age.” This important discovery shows the incredible adaptability of the human brain, providing insight into the way in which it can preserve motor function and other abilities as the human person ages.
To learn more about the discovery of brain layers that strengthen with age, please find the link attached here.