New brain cells can be formed through deep brain stimulation, improving memory retention, researchers report. For decades, scientists have been finding ways to generate brain cells to boost memory and learning, but more importantly, to also treat brain trauma and injury, and age-related diseases such as dementia. By stimulating the front part of the brain known as the prefrontal cortex, they have no discovered that new brain cells are formed in the hippocampus although it had not been directly stimulated.