Do you have EYES in the back of your head? No. You can only see what's in front of you! Yet, for your singing life it would really be great if you had eyes back there. Because if you did, you'd be more aware of the back of your neck. The muscles at the back of the neck include the trapezius, the occipital, and capitus muscles. These muscles tend to tighten during singing. This causes the back of the neck to shorten, the chin to thrust forward, and the head to lift upwards. All of these tendencies result in unwanted pressure on the larynx and can be a huge hindrance on vocal freedom. So, while you may not have eyes in the back of the head, pay attention back there anyway. It's bound to be a real eye-opener!