Images of Obsession; the Peculiar Symptoms of Obsessive-Compulsive Disorder Appear to Be Linked to a Mismatch in the Brain's Metabolic Activity

By Bower, Bruce | Science News, April 11, 1987 | Go to article overview
Save to active project

Images of Obsession; the Peculiar Symptoms of Obsessive-Compulsive Disorder Appear to Be Linked to a Mismatch in the Brain's Metabolic Activity


Bower, Bruce, Science News


Images of Obsession

Every day, a young woman shakesher clothes for a half hour and washes herself for up to six hours, haunted by the thought that germs might infect her with a deadly disease. A man cannot prevent himself from driving back to check every place on the road where he has hit a bump, because thoughts that he has run someone over torment him at every turn. Another man stops cooking for fear he will poison his wife and refuses to use electrical appliances because he worries about causing a fire.

These people illustrate some of thesymptoms of obsessive-compulsive disorder, a strange brew of recurrent ideas and impulses that are often experienced as repugnant (obsessions) mixed with ritualistic, seemingly senseless behaviors aimed at preventing harm and warding off anxiety (compulsions). An estimated 2 percent of the adult population in the United States suffers from obsessive-compulsive disorder at some time in their lives, and one-third of them develop the disorder during childhood.

French physician and psychologistPierre Janet described obsessive-compulsive disorder, using the term "psychasthenia,' in a classic 1903 publication. Not long afterward, Sigmund Freud conceived of obsessions and compulsions in his patients as complex psychological defenses used to deal with unconscious sexual and aggressive conflicts.

In contrast with this long history ofclinical observation, little is known about what parts of the brain help to produce the disorder's bizarre thoughts and acts. But that is beginning to change.

In the March ARCHIVES OF GENERALPSYCHIATRY, scientists at the University of California at Los Angeles School of Medicine suggest that there is an imbalance in the energy-conversion rates of two structures in the frontal lobes of obsessive-compulsives. The two brain regions normally work together to help channel and contron incoming sensations and perceptions.

While this metabolic mismatch accompaniesobsessive-compulsive symptoms, says psychiatrist and project director Lewis R. Baxter Jr., it is not necessarily a cause of the disorder.

The new report is based on positronemission tomography (PET) scans of 14 obsessive-compulsives, 14 individuals with severe depression and 14 controls with no psychiatric diagnoses. PET-scanning devices transform quantitative measures of metabolic activity throughout the brain into color-coded pictures. As in many other PET experiments, a radioactively labeled glucose compound was used to gauge tissue reponses, since glucose is a prime energy source in the brain.

Compared with depressed and controlsubjects, obsessive-compulsives had significantly increased glucose metabolism in a frontal lobe region on the left hemisphere, known as the left orbital gyrus. The right hemisphere's corresponding orbital gyrus showed no substantial jumps in activity. In addition, the metabolic rate in the left orbital gyrus, relative to that of the entire left hemisphere, was markedly elevated among obsessive-compulsives, and stayed high even among eight subjects whose symptoms eased after treatment within an antidepressant drug.

Since all of the obsessive-compulsivesubjects were right-handed, says Baxter, it appears that activity in the dominant-hemisphere orbital gyrus is most affected. A left-hander with the diagnosis was recently given a PET scan by the UCLA researchers, and an increased metabolic rate in the right orbital gyrus was observed.

Animal studies, notes Baxter, indicatethat the orbital gyri are involved in directing attention toward specific objects. Damage to this area can cause animals to engage in repetitive behaviors.

Two other frontal-lobe structures, thecaudate nuclei, located on opposing hemispheres, also displayed significant jumps in metabolic rate relative to overall hemisphere activity, but only among obsessive-compulsives who improved after drug treatment. Before treatment, the ratio of caudate activity to hemisphere activity was within the normal range for obsessive-compulsive subjects, and it did not increase among those whose symptoms did not improve.

The rest of this article is only available to active members of Questia

Sign up now for a free, 1-day trial and receive full access to:

  • Questia's entire collection
  • Automatic bibliography creation
  • More helpful research tools like notes, citations, and highlights
  • Ad-free environment

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
Loading One moment ...
Project items
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

Cited article

Images of Obsession; the Peculiar Symptoms of Obsessive-Compulsive Disorder Appear to Be Linked to a Mismatch in the Brain's Metabolic Activity
Settings

Settings

Typeface
Text size Smaller Larger
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

While we understand printed pages are helpful to our users, this limitation is necessary to help protect our publishers' copyrighted material and prevent its unlawful distribution. We are sorry for any inconvenience.
Full screen

matching results for page

Cited passage

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

Cited passage

Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

OK, got it!

Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.

For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

Already a member? Log in now.

Are you sure you want to delete this highlight?