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.

Related Articles


"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 January 30, 2015 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 January 30, 2015).

Share This


More From ScienceDaily



More Mind & Brain News

Friday, January 30, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Binge-Watching TV Linked To Loneliness

Binge-Watching TV Linked To Loneliness

Newsy (Jan. 29, 2015) Researchers at University of Texas at Austin found a link between binge-watching TV shows and feelings of loneliness and depression. Video provided by Newsy
Powered by NewsLook.com
Signs You Might Be The Passive Aggressive Friend

Signs You Might Be The Passive Aggressive Friend

BuzzFeed (Jan. 28, 2015) "No, I&apos;m not mad. Why, are you mad?" Video provided by BuzzFeed
Powered by NewsLook.com
City Divided: A Look at Model Schools in the TDSB

City Divided: A Look at Model Schools in the TDSB

The Toronto Star (Jan. 27, 2015) Model schools are rethinking how they engage with the community to help enhance the lives of the students and their parents. Video provided by The Toronto Star
Powered by NewsLook.com
Man Saves Pennies For 65 Years

Man Saves Pennies For 65 Years

Rooftop Comedy (Jan. 26, 2015) A man in Texas saved every penny he found for 65 years, and this week he finally cashed them in. Bank tellers at Prosperity Bank in Slaton, Texas were shocked when Ira Keys arrived at their bank with over 500 pounds of loose pennies stored in coffee cans. After more than an hour of sorting and counting, it turned out the 81 year-old was in possession of 81,600 pennies, or $816. And he&apos;s got more at home! Video provided by Rooftop Comedy
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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