At the beginning of the 1980’s in the United States Professor Rosenthal discovered the benefits of light therapy lamps. At first they were used in cases of seasonal depression also called SAD (Seasonal Affective Disorder). Light therapy is today practised in a number of hospitals a number of pathologies, but mostly with trouble linked to the upset of the biological clock (circadian rhythm problems) like insomnia and generally trouble sleeping. Light therapy lamps and seasonal depression or SAD. The principal symptoms of winter season depression start to show at the end of summer when the days start to grow short and become dull as there is less light it is the seasonal change that affects a number of people. In a number of cases it is Winter Blues which we all suffer from in one way or another, it is a simpler version of winter depression, and this in no way stops us from continuing with our daily lives. Get more info from www.hypnotherapistdirect.com.