Five diseases attack language areas in brain

There are five different diseases that attack the language areas in the left hemisphere of the brain that slowly cause progressive impairments of language known as primary progressive aphasia (PPA), reports a new Northwestern Medicine study.

“We’ve discovered each of these diseases hits a different part of the language network,” said lead author Dr. M. Marsel Mesulam, director of Northwestern’s Mesulam Center for Cognitive Neurology and Alzheimer’s Disease. “In some cases, the disease hits the area responsible for grammar, in others the area responsible for word comprehension. Each disease progresses at a different rate and has different implications for intervention.”

This study is based on the largest set of PPA autopsies—118 cases—ever assembled.

It will be published April 20 in the journal Brain.

“The patients had been followed for more than 25 years, so this is the most extensive study to date on life expectancy, type of language impairment and relationship of disease to details of language impairment,” said Mesulam, also chief of behavioral neurology at Northwestern University Feinberg School of Medicine.

Patients with PPA were prospectively enrolled in a longitudinal study that included language testing and imaging of brain structure and brain function. The study included consent to brain donation at death.

An estimated one in 100,000 people have PPA, Mesulam said.

Read more: Medical Xpress