You should begin at birth to show sensitivity to your environment by responding to
                  various stimuli (e.g., light, touch, temperature, movement). Very soon, you should
                  be able to fix your gaze on a human face. You should stop your activity when you hear
                  voices or sounds around you. Next, you should begin to attend to and follow various
                  moving objects with your gaze, including people or toys. You should be listening to
                  your family's conversations for longer and longer periods of time. Eventually, as
                  you are able to move around and explore your environment, you should begin to play
                  with people and toys for longer periods of time. You will still want to change activities
                  frequently, but your interest in continuing interaction or a game should gradually
                  expand.