What is the nucleus basalis of Meynert?

Answer: The nucleus basalis of Meynert is an acetylcholine producing projection area located in the basal forebrain.

nucleus basalis of meynert

The cortex is sensitive to modulation by acetylcholine. Most of the acetylcholine comes from axonal projections that originate in a small section of the basal forebrain, and this are of acetylcholine rich neurons is called the nucleus basalis of Meynert. It is within an area called the substantia innominata.

The are stains densely for choline acetyltransferase, the enzyme that is responsible for the synthesis of acetylcholine.

These projections into the cortex are believed to be relevant for attention and visual perception. The acetylcholine produced by these cells activate nicotinic acetylcholine receptors at Layer IV in the primary visual cortex, while also inhibiting another population through muscarinic receptor activation.

Deficits in functions in the nucleus basalis of Meynert are observed in neurodegenerative diseases such as Parkinson’s disease and Alzheimer’s disease. Because of these changes, the cholinergic system was implicated in playing a role in the cognitive symptoms observed in Alzheimer's disease, prompting researchers to consider cholinergic modifying drugs as a therapeutic approach.

The structure is named after Theodor Meynert, a German-Austrian anatomist.