Featured Research

from universities, journals, and other organizations

PET Scans Help Identify Mechanism Underlying Seasonal Mood Changes

Date:
September 4, 2008
Source:
JAMA and Archives Journals
Summary:
Brain scans taken at different times of year suggest that the actions of the serotonin transporter -- involved in regulating the mood-altering neurotransmitter serotonin -- vary by season, according to a new report. These fluctuations may potentially explain seasonal affective disorder and related mood changes.

Brain scans taken at different times of year suggest that the actions of the serotonin transporter—involved in regulating the mood-altering neurotransmitter serotonin—vary by season, according to a new report. These fluctuations may potentially explain seasonal affective disorder and related mood changes.

"It is a common experience in temperate zones that individuals feel happier and more energetic on bright and sunny days and many experience a decline in mood and energy during the dark winter season," the authors write as background information in the article. This is thought to be related to variations in brain levels of serotonin, which is involved in the regulation of functions such as mating, feeding, energy balance and sleep. The serotonin transporter, a protein that binds to serotonin and clears it from the spaces between brain cells, "is a key element in regulating intensity and spread of the serotonin signal."

Nicole Praschak-Rieder, M.D., and Matthaeus Willeit, M.D., of the Centre for Addiction and Mental Health and the University of Toronto, Ontario, Canada, and colleagues studied 88 healthy individuals (average age 33) between 1999 and 2003. Participants underwent one positron emission tomography (PET) scan to assess serotonin transporter binding potential value, an index of serotonin transporter density. The higher the binding potential value, the less serotonin circulates in the brain. For the analysis, individual scans were grouped according to the season of the scan—fall and winter or spring and summer.

"Serotonin transporter binding potential values were significantly higher in all investigated brain regions in individuals investigated in the fall and winter compared with those investigated in the spring and summer," the authors write. When they matched binding potential values to meteorological data, the researchers found that higher values occurred during times when there were fewer hours of sunlight per day.

"An implication of greater serotonin transporter binding in winter is that this may facilitate extracellular serotonin loss during winter, leading to lower mood," the authors write. "Higher regional serotonin transporter binding potential values in fall and winter may explain hyposerotonergic [related to low serotonin levels] symptoms, such as lack of energy, fatigue, overeating and increased duration of sleep during the dark season."

"These findings have important implications for understanding seasonal mood change in healthy individuals, vulnerability to seasonal affective disorder and the relationship of light exposure to mood," they conclude. "This offers a possible explanation for the regular reoccurrence of depressive episodes in fall and winter in some vulnerable individuals."

This study was supported by grants from the National Alliance for Research on Schizophrenia and Depression, the Austrian Science Foundation, the Canadian Institute for Health Research, the Ontario Mental Health Foundation, the Canada Foundation for Innovation and the Ontario Innovation Trust.


Story Source:

The above story is based on materials provided by JAMA and Archives Journals. Note: Materials may be edited for content and length.


Journal Reference:

  1. Praschak-Rieder et al. Seasonal Variation in Human Brain Serotonin Transporter Binding. Archives of General Psychiatry, 2008; 65 (9): 1072 DOI: 10.1001/archpsyc.65.9.1072

Cite This Page:

JAMA and Archives Journals. "PET Scans Help Identify Mechanism Underlying Seasonal Mood Changes." ScienceDaily. ScienceDaily, 4 September 2008. <www.sciencedaily.com/releases/2008/09/080901205721.htm>.
JAMA and Archives Journals. (2008, September 4). PET Scans Help Identify Mechanism Underlying Seasonal Mood Changes. ScienceDaily. Retrieved July 22, 2014 from www.sciencedaily.com/releases/2008/09/080901205721.htm
JAMA and Archives Journals. "PET Scans Help Identify Mechanism Underlying Seasonal Mood Changes." ScienceDaily. www.sciencedaily.com/releases/2008/09/080901205721.htm (accessed July 22, 2014).

Share This




More Mind & Brain News

Tuesday, July 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Do Obese Women Have 'Food Learning Impairment'?

Do Obese Women Have 'Food Learning Impairment'?

Newsy (July 18, 2014) Yale researchers tested 135 men and women, and it was only obese women who were deemed to have "impaired associative learning." Video provided by Newsy
Powered by NewsLook.com
Does Mixing Alcohol and Energy Drinks Boost Urge To Drink?

Does Mixing Alcohol and Energy Drinks Boost Urge To Drink?

Newsy (July 18, 2014) A new study suggests that mixing alcohol with energy drinks makes you want to keep the party going. Video provided by Newsy
Powered by NewsLook.com
Pot Cooking Class Teaches Responsible Eating

Pot Cooking Class Teaches Responsible Eating

AP (July 18, 2014) Following the nationwide trend of eased restrictions on marijuana use, pot edibles are growing in popularity. One Boston-area cooking class is teaching people how to eat pot responsibly. (July 18) Video provided by AP
Powered by NewsLook.com
Understanding D.C.'s New Pot Laws

Understanding D.C.'s New Pot Laws

Newsy (July 17, 2014) Washington D.C.'s new laws decriminalizing small amount of marijuana went into effect Thursday. Here's how they work. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins