Accessing member name

Hi,

How is the member name accessed programmatically? I'm using Umbraco 4.7.

I have seen some posts related to this but no resolution. Umbraco 4.x is using the .NET membership provider with the Umbraco member deprecated. How do I access and set a member name? It currently seems to be set the same as the member UserName, which is not what I want.

Where is this documented?

Thanks.