Yes, you can do this by doing the following:

  1. Enable 'Record Webcam' on the main Recorder window 
  2. Click Settings
  3. Go to the WebCam tab
  4. Enable the 'Record only from webcam and not the screen' option

Note - Webcam only recordings will be saved as .flv files instead of .fbr files. This means that they cannot be opened in FlashBack Player. However, you can convert .flv files into .fbr files for editing in FlashBack.