a positive declaration intended to give confidence: He received assurances of support for the project. 2. promise or pledge; guaranty; surety: He gave his assurance that the job would be done. 3. full confidence; freedom from doubt; certainty: to act in the assurance of success.
Summary. Traumatic brain injury (TBI) happens when a bump, blow, jolt, or other head injury causes damage to the brain. Every year, millions of people in the U.S. suffer brain injuries. More than half are bad enough that people must go to the hospital. The worst injuries can lead to permanent brain damage or death.
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. Gradually, this damage causes difficulties in thinking and behaviors normally controlled by these parts of the brain.