I am a strong believer that you shouldn’t change point of view (POV) in a scene. If you want to show what another character is thinking, use the three stars * * * and then reveal the other person’s perspective.
Often writers switch point of view in the same scene. The writer can make this switch skillfully by calling attention to the person and then sliding into the mind of the person. But frequently it’s done without skill. The danger of switching point of view in one scene is that the reader might get “POV whiplash.”
I think it pushes our skill to show what another person is thinking without switching point of view. While we’re in Jack’s head, we readers see how Jack observes Marsha. He does this by noting her actions, her body language, etc. We find out what Marsha is thinking without switching into her head.
Someone told me once, “Don’t play ping-pong with your readers.”