Brain plasticity refers to the ability of the brain to modify its own structure and function following changes within the body or in the external environment. The large outer layer of the brain, known as the cortex, is especially able to make such modifications.
Deeper dive
Brain plasticity is at the root of normal brain function, such as our ability to learn and modify our behavior. It is strongest during childhood — explaining the fast learning abilities of kids — but remains a fundamental and significant lifelong property of the brain.
Adult brain plasticity has been clearly implicated as a means for recovery from sensory-motor deprivation, peripheral injury, and brain injury. It has also been implicated in alleviating chronic pain and the development of the ability to use prosthetic devices such as robotic arms for paraplegics, or artificial hearing and seeing devices for the deaf. According to the Society for Neuroscience, there is increasing understanding of the role that brain plasticity plays in psychiatric and degenerative brain disorders.
Scientists now know that the organization of brain circuitry is constantly changing as a function of experience. These changes are referred to as brain plasticity, and they are associated with functional changes that include phenomena such as memory, addiction and recovery of function. Recent research has shown that brain plasticity and behavior can be influenced by many factors, such as drugs, hormones, maturation, aging, diet, disease and stress. Understanding how these factors influence brain organization and function is important not only for insight into both normal and abnormal behavior, but also for designing treatments for behavioral and psychological disorders ranging from addiction to stroke.
Aging is associated with progressive losses in function across multiple systems, including sensation, cognition, memory, motor control and affect. The traditional view has been that functional decline in aging is unavoidable because it is a direct consequence of brain machinery wearing down over time. In recent years, an alternative perspective has emerged, based upon decades of research in neuroscience, experimental psychology, and other related fields. This perspective argues that as people age, brain plasticity processes with negative consequences begin to dominate brain functioning. Four core factors — reduced schedules of brain activity, noisy processing, weakened neuromodulatory control, and negative learning — interact to create a self-reinforcing downward spiral of degraded brain function in older adults. This downward spiral might begin from reduced brain activity due to behavioral change, from a loss in brain function driven by aging brain machinery, or more likely from both.
These combined, interrelated factors promote plastic changes in the brain that result in age-related functional decline. Studies of adult brain plasticity have shown that substantial improvement in function and/or recovery from losses in sensation, cognition, memory, motor control and affect should be possible using appropriately designed behavioral training paradigms. Brain plasticity shows the ability of the brain to change throughout life by forming new connections between brain cells and to alter function. For a long time, it was assumed that as we become older, the connections in the brain became fixed, and then it was just a matter of time that we started “losing” brain cells. However, this assumption is being aggressively challenged by recent studies showing that the brain never stops changing.