Seasonal affective disorder (SAD) is a recognised mental health disorder. It is a type of depression that tends to occur during autumn/winter and eases over spring/summer.

Most people feel uplifted by the longer, warmer days of summer and somewhat sad as the days grow shorter, darker and cooler. However, for sufferers of Seasonal Affective Disorder, the onset of autumn can have a significant impact on their mood and energy levels, with severe symptoms of depression that affect day-to-day activities. SAD patients will struggle with severe depression for 4-6 months of the year.

Figures indicate that:

  • 2% of the population in Northern Europe have severe depression resulting from Seasonal Affective Disorder
  • In the UK, up to 6% of adults have ‘recurrent major depressive episodes with seasonal pattern’

Symptoms of Seasonal Affective Disorder

  • Persistent low mood
  • Loss of pleasure or interest in normal everyday activities
  • Irritability
  • Feeling despair, guilt, worthlessness
  • Lethargy (lacking in energy)
  • Feeling sleepy during the day
  • Sleeping for longer than normal and finding it hard to get up in the morning
  • Craving comfort food and carbohydrates, weight gain


While the exact cause of SAD is not fully understood, it is believed to be due to a reduction in exposure to sunlight during the shorter days in autumn/winter. Researchers have found that people with SAD may have an imbalance of serotonin, a brain chemical that affects a person’s  mood.

Experts believe that reduced sun exposure may impair hypothalamus functioning, the effects of which include:

  • Higher melatonin production – interfering with sleep patterns
  • Lower serotonin production – linked to depression and also affecting appetite and sleep
  • Disrupted circadian rhythm – upset body clock, sleeping/waking patterns

Conventional Treatments

Conventional approaches to treating Seasonal Affective Disorder include:

  • Lifestyle – getting outdoors as much as possible to maximise sunlight exposure. Exercising and managing other factors for depression, e.g. stress
  • Light therapy – special lamps or lightboxes to simulate sunlight exposure
  • Psychotherapy – talking therapies, counselling
  • CBT – cognitive behaviour therapy
  • Medication – antidepressants

rTMS Treatment for Seasonal Affective Disorder

Evidence shows that TMS may be a suitable alternative treatment for SAD.

It is a safe, medication free treatment which works directly on the affected areas of the brain with a non-invasive therapy.

The rTMS treatment for depression stimulates the prefrontal cortex area of the brain.  This area controls mood, motivation, and social skills.  In particular, the left side of the prefrontal cortex is associated with positive feelings.  It is this area of the brain that is stimulated by rTMS. Stimulation of the prefrontal cortex by rTMS in depressed patients can lead to complete remission from depression with patients reporting that they feel much more positive; they are more sociable, motivated and talkative.

NICE Approved Treatment of Depression with rTMS

NICE approved rTMS as a safe and effective treatment for depression in December 2015 (NICE Guidelines, 2015).


Seasonal Affective Disorder

TMS Treatment Clinics

Transcranial Magnetic Stimulation therapy treatment for Seasonal Affective Disorder is available at all Smart TMS clinics. Smart TMS was the first UK clinic to offer treatments for anything other than depression.  See our clinic locations for more information.

Treatment Protocol

At Smart TMS we provide a bespoke rTMS depression treatment, using our extensive experience of rTMS in the treatment of depression and our ongoing discussions with various researchers. Each treatment session takes 25 minutes.

The treatment protocol as outlined by NICE is typically 2-6 weeks.  We have developed treatment protocols which allow for multiple treatments per day, allowing for the full treatment to be delivered in between five days up to six weeks, at the patient’s discretion.  Patients will be assessed over the course of treatment to monitor the effect.  The actual length of the treatment will vary dependent on how quickly a reduction in the depression level is seen.