This was an intended change in the MATLAB 7.0 (R14) keyboard functionality. Henceforth, you can use the Ctrl+PgUp and Ctrl+PgDn to cycle among documents instead of Ctrl+Tab and Ctrl+Shift+Tab.
In MATLAB 7.0 (R14), common keyboard shortcuts are as follows:
1. Ctrl+Tab and Ctrl+Shift+Tab cycle forward and backward through the tools open in the MATLAB desktop.
2. Ctrl+PgUp and Ctrl+PageDn cycle through tabbed components or documents in a container such as the Editor.
3. On Windows, Ctrl+F6 and Ctrl+Shift+F6 cycle through all open components.
4. Ctrl+0 and Ctrl+Shift+0, enable you to switch between the Command Window and the most recently accessed file in the Editor, whether or not they are docked in the MATLAB desktop or not.
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