What Part of the Brain Controls Irritability?

If you know someone who seems to always be in a bad mood, the problem is probably in the deep limbic system. The deep limbic system is the area of the brain responsible for irritability, moodiness, and negative thinking in general.

Identification

• The deep limbic system is very intimately connected to the prefrontal cortex and acts like a "switching station between running on emotion (the deep limbic system) and rational thought and problem solving using our cortex", according to Daniel G. Amen, author of "Change Your Brain, Change Your Life: The Breakthrough Program for Conquering Anxiety, Depression, Obsessiveness, Anger, and Impulsiveness."

Function

• When the limbic system is turned on, so to speak, emotions take control. When the limbic system turns down - or "cools off" as Amen calls it, there is more activity in the cortex. Amen notes that studies have shown "a correlation between depression and increased deep limbic system activity and shutdown in the prefrontal cortex, especially on the left side."

Problems

• Problems in the deep limbic system can make a person irritable and moody. Some other problems that occur may be negative thinking and perception of life, lack of motivation, outpouring of negative emotions, sleep issues and decrease in appetite, lack of sexual interest, as well as social phobias and issues.

Theories/Speculation

• Increased activity on the left side of the limbic system is often linked to irritability while increased activity on the right side of the deep limbic system is often linked with sadness, anxiety, and repressed negative emotion, according to Amen. Left-side abnormalities are often more difficult for other people to deal with in an irritable person because the anger and irritability is expressed outwardly while right-side over-activity is more of an internal struggle.

Potential Treatments

• Some treatments for irritability caused by a problem in the deep limbic system are medications such as Depakote, Neurontin (gabapentin), Lamictal (lamotrigine), or Tegretol (carbamazepine). These drugs are known for evening out moods and calming inner turmoil, lessening irritability, and aiding the irritable person in a way so that they feel more relaxed in general, according to Amen.