Do you sometimes get into a bad mood spiral?
You have a thought (that you’re probably not even aware of) and – bang – a bad mood tumbles uncontrollably through your head like a collapsing chain of dominoes.
Before you know it you’re stomping through the house, slamming doors, grunting and your family members are fleeing out the door to get away from you.
Sound familiar?
Neuroscientists are coming closer to understanding how bad moods arise. Thanks to deep brain recordings of electrical activity they’ve found some interesting insights. Dark clouds move over, the sun’s coming out!
The spiral into a bad mood may occur in a brain network that connects two key regions involved with memory and negative emotions, says psychiatrist Vikaas Sohal at the University of California, San Francisco. In a study he co-authored, published in November in Cell, Sohal says he was able to tell if someone’s mood was getting worse just by looking at whether this network was active or not.
Psychiatrists have previously used MRI (magnetic resonance imaging) scans to probe the human brain and the world of emotions within it. This technology can show how brain activity changes within a few seconds, but the brain tends to work a lot faster than that—neurons can fire dozens of times a second. MRI readings might miss things that happen too quickly. Implanted electrodes, however, can measure changes in brain activity up to 1,000 times a second. So when University of California, San Francisco neurosurgeon Edward Chang popped into Sohal’s office with an idea to use internal electrodes to elucidate the neurological underpinnings of mood, Sohal was delighted.
The brain surgery needed to implant electrodes is too risky to perform on healthy individuals for a study like this—but Chang works on epilepsy patients who need them anyway. When other treatments do not work, temporarily implanted electrodes can show what part of the brain is causing seizures, allowing Chang to cut that section out during surgery. By asking such patients to report their moods every few hours, the team hoped they could use the electrodes to get a rare window into emotion and the deep brain. Scientists know that mood is somewhere in the brain but their goal was to see if they could find patterns of activity that indicate what mood is.
Chang implanted electrodes on the surfaces and inside the brains of 21 patients with epilepsy, recording the organs’ activity continuously for seven to 10 days. Then Sohal scoured the recordings for instances when electrodes in different parts of a brain showed identical measurements of electrical activity. Electrical activity of the brain looks like ‘wiggles’ from each electrode when displayed on a graph. Sohal wondered if the size of those ‘wiggles’ and the locations of the peaks go up together in sync across two electrodes. If they did, it would suggest those brain regions are communicating. That is then called a network.
One particular network connecting the hippocampus (an area linked to remembering) and the amygdala (an area linked to negative feelings and fear) began appearing over and over in the measurements. That was the researchers’ first big ‘Aha!’ moment. Whenever those two brain regions created synchronised electrical pulses that fluctuated between 13 to 30 times a second, people reported their moods getting worse. The researchers found that when there was less activity in this network, mood was more positive. When there was a lot of activity in the network, mood was negative.
The finding brings scientists closer to understanding how the brain creates bad moods. There’s a major open question in psychiatry: How do you construct emotion or mood? People have a very vague idea of what it means to perceive or have an emotion in the brain. This study is a big step for neuroscience.
Sohal team’s findings spark ideas about how the brain generates negative moods. It’s possible, for example, that when these two brain regions work together they create a vicious cycle that drags you down a bad road. It’s easy to imagine that you might be feeling bad, and then remembering bad experiences, and then feel worse.
If that’s right, doctors might figure out how to interrupt that cycle with deep-brain stimulation or electroshock therapy for people with major depressive and anxiety disorders. If this is the part of the brain that makes you feel bad, maybe you could reverse how that’s firing and get yourself to feel better….but it will be a long haul before this knowledge could be used in the clinical setting. However, for those of us in the psychotherpay and healing arenas, becoming aware of your triggering throughts and then shifting them is a great way to bypass this downward spiral.