When the brain suffers damage, often slower brainwaves — delta and theta — rush to the site of the injury to begin repairing. These are the brainwaves babies, toddlers and youth spend much time in while their brains are developing because these are the cell growth frequencies.

These slow waves are the waves of angiogenesis, neuroplasticity, and neurogenesis.

Thus, it makes perfect sense that the brain would produce these waves when trying to regenerate damaged tissue. In many cases of head injury the patterns of delta and theta become locked, entrenched, and habitual, preventing growth out of the concussed / stroke / TBI disabled state.