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Seasonal Affective Disorder

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Seasonal Affective Disorder

Mark A. Spezzano

Abstract:  This article focuses on the treatment of seasonal affective disorders (SAD). Definition of SAD; List of atypical physical symptoms experienced by people with SAD; Phenomenon that causes jet lag in travelers.

For this paper, I decided to conduct a literature search on Seasonal Affect Disorder (SAD) and the associated lack of healthy light which contributes to depression type symptoms.  Although there are many treatments that help with this mind-body scenario, this paper will focus on light box treatment. 

SAD is a form of depression that begins in the fall or early winter and generally lasts from 5-7 months until spring.  The early loss of sunlight in the winter appears to induce chemical changes in the brain that bring on depression (Barbor, 2002; Rohan, et al., 2003).  This lack of sunlight causes a reduction in serotonin production and an elevation in the level of melatonin.  Melatonin is created by the pineal gland.  It is activated at night and shut off in the morning; melatonin secretion brings on sleep and may help to synchronize other circadian rhythms (“Winter Depression,” 2004).   Moreover, a “confused” circadian rhythm is what some research has shown to be responsible for producing the symptoms associated with SAD (Rohan, et al., 2003).

Light therapy as a natural treatment was developed on the basis of circadian rhythm research (Ennis & McConville, 2004).  The “antidepressant” effect of light box therapy has been well established (Ennis & McConville, 2004; Barbor, 2002; Goel, Terman, & Terman, 2003).  However, hypotheses about the physiological basis of SAD and the different approaches of light therapies (i.e., light intensities, duration, and time of day of treatment) are subject of controversial discussion (Goel, Terman, & Terman, 2003).

Symptoms of SAD may fluctuate in severity, but are characterized by their seasonal occurrence.  Symptoms may include: 

  • Lack of energy
  • Increased desire to sleep
  • Depression 
  • Increased appetite leading to weight gain 
  • Anxiety 
  • Difficulty concentrating 
  • Irritability 
  • Withdrawal
  • Difficulty with relationships
  • Loss of sexual desire 
  • Increase in Premenstrual Syndrome-related symptoms in women
SAD is different from other forms of depression; although it has similar symptoms, due to its profound seasonal nature (Barbor, 2002; “Winter Depression,” 2004). 

As mentioned previously, bright light therapy appears to be an extremely effective treatment for SAD.  A standard morning light therapy regimen often consists of exposure to a 10,000-lux, cool-white fluorescent light for 30 minutes-2 hours a day (“Winter Depression,” 2004; Goel, Terman, & Terman, 2003).  This therapy requires special lamps that provide from 5-20 times the normal brightness of home or office lighting.  The research shows that using a 10,000-lux light is akin to early morning sunlight.  Research also demonstrates that it is not necessary to match the exact color spectrum of visible sunlight (“Winter Depression,” 2004; Barbor, 2002).  Furthermore, the studies show that morning light is “usually preferred because it is supposed to reset the body’s clock by moving internal cycles forward and synchronizing them with the rhythm of daylight and darkness” (“Winter Depression,” 2004 p.5). 

There appears to be a lot of empirical data that support the efficacy of light box therapy (Barbor, 2002).  For this paper, I focused on the research by Namni Goel, Michael Terman, and Jiuan Su Terman (2003).  The authors used 89 research volunteers enrolled in various winter depression light treatment studies.  The gender breakdown was 69 women and 20 men (Goel, Terman, & Terman, 2003 p.91). 
After all the preliminary benchmarking (i.e., social history, pre-tests, appropriate DSM diagnoses, and observations), Goel and associates utilized a rapid assessment instrument, that in my opinion, was unique in SAD research.  They utilized the Tridimensional Personality Questionnaire (TPQ).  This instrument is a 100 item self-report inventory that breaks respondents into three personality types - novelty seeker (NS), harm avoidant (HA) and reward dependent (RD) (Goel, Terman, & Terman, 2003 p.89).  Once they grouped each of the 89 participants, they administered bright light treatment (10,000-lux light for 30 minutes) once every day.  They chose to administer this treatment daily either in the morning or the evening for 10–14 days (2003 p. 91). 

Interestingly enough, they discovered that one’s temperament plays a large role on the effectiveness of light box therapy (Goel, Terman, & Terman, 2003 p. 94).  They found those subjects who were typed through the TPQ as either RD or NS tended to be better candidates for light therapy.  Meanwhile, those participants who were primarily typed as HA personalities, improved spontaneously - with or without light box treatment (p. 95).  Finally, the authors conclude that “baseline HA scores in [their] patients may have shown comparable elevation in both responders and non-responders due to factors contributing to depression that are not predictive of treatment response” (p. 95).

In conclusion, along with the aforementioned study by Goel and associates (2003) and others (Barbor, 2002; Ennis & McConville, 2004; Rohan, Sigmon, & Dorhofer, 2003), there appears to be a direct connection between SAD and the associated lack of healthy light.  The utilization of 10,000-lux light box treatments appears to mitigate depression type symptoms.  Finally, it further shows that this is a direct mind-body connection.  If one is able to help the mind (melatonin/serotonin) through light therapy, s/he is able to help control some of the associated negative physical symptoms of seasonal depression.


Barbor, C. (2002, November/December). Don’t be sad. Psychology Today, 
Volume 35, Issue 6; pg. 54: New York.
Abstract:  Seasonal Affective Disorder (SAD) affects some ten million Americans, and an additional 25 million Americans suffer from a milder form of the condition. Using bright light therapy to shift the internal circadian clock is the most effective 
intervention for SAD.

Ennis, E. & McConville, C. (2004, April) Stable characteristics of mood and 
seasonality.  Personality and Individual Differences, Vol 36 (6), pp 1305-
Abstract: Seasonal variations in mood and behaviour appear to be best understood through an integration of biological and psychological research. Disturbances in mood are the main psychological component of seasonality. This paper examines the hypothesis that elevated levels of mood variability, decreased average levels of positive affect and increasedaverage levels of negative affect may be characteristic of the overall mood profile associated with acute previous seasonal disturbances in mood and behaviour. During the winter months of January and February, 59 volunteers (10 males, 49 females; overall mean AGE=28) completed the 
Seasonal Pattern Assessment Questionnaire (SPAQ) and subsequently completed the 20-item version of the Positive and Negative Affect Schedule (PANAS) twice daily for a fortnight. Participants were not clinically diagnosed sufferers of Seasonal Affective Disorder (SAD). Mood profile co-varied with severity of seasonal disturbances in mood and behaviour. While seasonality was unrelated to average mood levels, it was significantly positively associated with mood variability.  Considering SAD as the extreme end of the continuum of intensities of seasonality, further examination of the biological and psychological importance of mood variability within the aetiology of SAD is warranted.

Goel, N., Terman, M., & Terman, J.S. (2003, July 15). Dimensions of  temperament and bright light response in seasonal affective disorder.  Psychiatry Research, Volume 119, Issues 1-2 , pp 89-9.
Abstract: Scale scores on the Tridimensional Personality Questionnaire (TPQ)—novelty seeking (NS), harm avoidance (HA), and reward dependence (RD)—can predict response to antidepressants. This study examined 89 patients with Bipolar Disorder (I, II) or Major Depressive Disorder, both with recurrent winter seasonal pattern. The TPQ was administered while the patients were depressed, following 10–14 days of bright light therapy (30 min, 10,000 lux) and after spontaneous springtime remission. The Structured Interview Guide for the Hamilton Depression Rating Scale—Seasonal Affective Disorder Version (SIGH-SAD) assessed the severity of depression. At baseline, there were no significant differences between diagnostic subgroups or responders and non-responders on the TPQ or SIGH-SAD scales, though baseline RD scores were significantly higher in women than men. Furthermore, neither severity of depression nor magnitude of post-treatment clinical improvement was significantly correlated with baseline TPQ scores. Only HA scores decreased after treatment, with responders showing the greatest effect. HA scores also decreased from the baseline to springtime assessments for the group as a whole, with no difference between responders and non-responders. This is the first study to demonstrate that HA is state- rather than trait-dependent in seasonal affective disorder. The TPQ dimensions of temperament do not predict response to previous light therapy.

Lake, J. (2000, May). Psychotropic medications from natural products: A review 
of promising research and recommendations. Alternative Therapies in 
Health and Medicine. Vol 6(3): 36, 39-45, 47-52.
Abstract:  Most psychotropic agents employed in allopathic medicine have limited efficacy and significant side effects. Although usually beneficial, synthetic psychotropics are unavailable to approximately 80% of the world's population. Improved understanding of appropriate and safe uses of naturally occurring substances as psychotropic agents will greatly contribute to global mental healthcare. Empirical validation of non-allopathic treatments to ensure safety and efficacy is important because increasing numbers of patients in economically developed countries are using natural substances as medicinal agents. Patients and clinicians often lack accurate information, resulting in poor treatment outcomes or the possibility of drug-drug interactions when herbal medications are used with synthetic psychotropic medications. An important objective of this paper is to distinguish compelling scientific evidence supporting the use of natural products in psychiatry from political or institutional biases that have been misrepresented as scientific arguments. Following an overview of historical, legal, and regulatory issues, this paper presents findings of a systematic literature review on natural products used to treat neuropsychiatric disorders. Significant recent research is reviewed, including emerging treatments of seizure disorders, schizophrenia, dementia and age-related cognitive decline, depression, anxiety states, and substance abuse. Substantial evidence is advanced for safety and efficacy of many natural products used to treat neuropsychiatric symptoms or disorders. Preliminary findings suggest that several treatments based on natural substances are as effective and safe as synthetic pharmaceuticals in current use. Additional studies are indicated to confirm these findings, to elucidate mechanisms of action, and to elaborate standards for safe and appropriate treatment indications. In conclusion, strategic approaches aimed at facilitating improved networking, accelerating promising research directions, and enhancing quality standards of ongoing investigations into putative psychotropic agents from natural sources are recommended.

Rohan, K.J., Sigmon, S.T., & Dorhofer, D.M. (2003, February).  Cognitive–
Behavioral factors in seasonal affective disorder.  Journal of Consulting 
and Clinical Psychology, Vol 71 (1), pp 22-30.
Abstract: To longitudinally examine cognitive–behavioral correlates of previous seasonal affective disorder (SAD), the authors assessed women with a history of SAD and nondepressed, matched controls across fall, winter, and summer. SAD history  participants reported more automatic negative thoughts throughout the year than controls and demonstrated a progression from decreased activity enjoyment during fall to reduced activity frequency during winter. Ruminative response style, measured in fall, predicted symptom severity during the winter. Across assessments, SAD history women endorsed greater depressive affect in response to low light intensity  stimuli than to bright or ambiguous intensity stimuli, but less depressed mood to bright light stimuli than controls. These results suggest that the cognitive–behavioral factors related to nonseasonal depression may play a role in SAD.

Winter depression. (2004, November). Harvard Mental Health Letter, Vol. 21 
Issue 5, p4-5.