The galea aponeurotica is a fibrous tissue structure located on the top of the skull. It acts as a connective layer between the skin of the scalp and the underlying muscles. This structure is part of the scalp and plays a crucial role in the movement and stability of the scalp during facial expressions. The galea aponeurotica is composed of dense connective tissue and serves as an attachment point for several muscles, including the frontalis and occipitalis. It helps facilitate the movement of the scalp and contributes to the overall function of the muscles of facial expression.