Neurological Disorders: Brain Tumors, Strokes, Traumatic Brain Injury, and Infections

The MMR Vaccine Controversy and Its Popularity

The MMR (Measles, Mumps, Rubella) vaccine-autism link gained significant popularity, not due to rigorous science, but celebrity endorsement.
Jenny McCarthy, then wife of comedian Jim Carrey, had a child diagnosed with autism.
She became a national proponent of a causal link between the MMR vaccine and autism, leveraging her platform.
The speaker emphasizes that McCarthy, a former Playboy bunny, later divorced Carrey and promoted other unverified health claims (E6), indicating she is not a reliable source for healthcare advice.
The original research article linking MMR to autism was based on a small, limited number of subjects and lacked rigorous vetting, making its scientific credibility poor.

Definition: A neo (new) plasm (growth) is a mass of cells that grows independently from the rest of the body.
Major Classifications:
- Encapsulated Tumors: Contained within their own membrane.
  - Generally have a better outcome.
  - Meningiomas: Represent 20\% of encapsulated tumors. They compress brain tissue, causing damage primarily from pressure, leading to cell death or damage. They are mostly benign (non-cancerous).
- Infiltrating Tumors: Lack a membrane, break through tissue, and can cause widespread damage.
Benign vs. Malignant:
- Benign: Not cancerous; cells grow but do not infiltrate other tissues.
- Malignant: Cancer cells; they infiltrate other cells, cause cell death, interfere with blood flow, and are very damaging.
Types of Infiltrating Brain Tumors:
- Typically malignant, they grow, spread, and may metastasize.
- Gliomas or Glioblastomas: Malignant tumors that originate in the glia cells of the brain.
- Metastatic Brain Tumors: Represent 10\% of all infiltrating brain tumors. These tumors originate outside the brain (e.g., breast cancer, gastrointestinal cancers, lymphatic cancers) and migrate to brain tissue.
  - Often, cancers in organs that secrete have thin cell walls, allowing cancerous cells to enter the bloodstream or lymphatic fluids and metastasize (spread).
  - Example: Melanoma that migrates to the brain.