Practical application- SAD

• One of the most effective treatments for SAD is phototherapy
• this is a lightbox that stimulates very strong light in the morning and evening
• it is thought to reset melatonin levels in people with SAD
• this relieves symptoms in up to 60% of sufferers (Eastman et al 1998)
• however, the same study recorded a placebo effect of 30% using a ‘sham negative-ion generator’ (participants were told it was another form of treatment)
• this casts doubt on the chemical influence of phototherapy