[Gravitational] waves are perturbations of spacetime which travel at c. However, spacetime is allowed to expand and contract faster than c. An expansion followed by a compression is pretty much the definition of a compression wave.
Damage to the brainâs frontal and temporal lobes causes forms of dementia called frontotemporal disorders. Frontotemporal disorders are the result of damage to neurons (nerve cells) in parts of the brain called the frontal and temporal lobes. As neurons die in the frontal and temporal regions, these lobes atrophy, or shrink.
The Frontal Lobe is the Largest Lobe. A stroke affecting the front portion of the frontal lobe causes behavioral problems, lack of inhibition and significant memory problems. Dementia of any type (Alzheimer's, Picks disease, vascular dementia) preferentially destroys the nerve cells in the frontal lobe.