Vista - Binding collection on ItemsSource - refresh problems

I created my own collection
public MyCollection<T> : CollectionBase{ }

Then i want to bind an ItemsSource on this collection. But when i add or
update item in my collection, the itemsource does not reflect the changes.

Is there a way to force the itemsource to reflect the changes ? Do I have to
implement a particular interface for MyCollection ?

Note : T is INotifyPropertyChanged