That's a great question! I apologize Constant Contact does not have the ability to control your images in this way. Images automatically appearing in your email depends on your specific email settings. Have you checked the settings in your email client to make sure images are enabled to display? If you have not enabled your images, I would suggest making this update.
While Constant Contact does not have the specific feature you are looking for, you may still be able to have the pictures displayed depending on your email provider and settings. There will be an area with options for enabling picture display. Ensure those are checked.