Could this man's grumpiness provide clues to the health of his brain?

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Emotional Intelligence and the Brain

A person's IQ score has remained the gold standard in intelligence debates; it's the kind of number that goes on your permanent record. As a result, scientists have tried to use this little number as a way to ascertain the state of the brain. Take the case of dementia, in which memory fails and a person begins to lose the ability to remember simple facts and tasks. A decline in cognitive function, illustrated by a falling IQ score, has been used as a mean of predicting dementia.

However, this method has some failings, because people with very high IQs display the symptoms of dementia much later, and they score above predictive norms on cognitive tests. These people then decline much faster once they begin exhibiting symptoms because the disease has already progressed. Because they score so much higher than the norms, they miss out on valuable early intervention opportunities. Conversely, those with lower IQs have the potential to be misdiagnosed with dementia because they score below the cognitive norms [source: APA].

Because dementia usually includes an emotional component as well as these failings in memory, it may be useful to factor in someone's emotional intelligence during diagnosis. But how does emotion even factor into the brain? While many parts of the brain may be involved in regulating emotion, it really comes down to what's going on in the left and right hemispheres. The right side of the brain takes in the sensory information related to emotions and processes it. Then, that information is sent to the left side of the brain, which is responsible for language. The left side of the brain gives these emotions a name. Also central to the process are the cerebellum, amygdala and the corpus callosum, which transfers the information between the right and left hemispheres. While we may not know everything about emotional intelligence, it's reasonable to assume that a low level of it is due to a malfunction in one of these parts of the brain.

But can we use that knowledge to ascertain brain health? Not yet, since scientists still don't know exactly what causes many brain disorders. However, emotional intelligence may prove to be most valuable in terms of identifying and addressing risk factors. For example, smoking is a risk factor for many brain disorders, but a study conducted by a Barcelona university found that students with high emotional intelligence were less likely to consume tobacco or cannabis [source: Universitat Autonoma de Barcelona]. These students seemed to be able to regulate their emotional state so that they were less tempted to use tobacco products, while those with lower emotional intelligence may be drawn to substance abuse to compensate for a poor emotional state.

Similarly, while a person with a high IQ may know the basics of nutrition, it may take an emotionally intelligent person to make the right food choices. In one study, researchers found that those with higher emotional intelligence were able to make better product choices in the store [source: University of Chicago Press Journals]. The ability to select healthier products may protect the emotionally intelligent from the extremely dangerous risk factor of obesity.

Emotional intelligence has also been linked to better stress management and lower psychological distress, as well as lower rates of depression [source: Austin et al.]. When people are unable to recognize and control their emotions, they're more likely to have lower satisfaction with life. Does someone dissatisfied with life sound fun to be around? While it might sound obvious, emotionally intelligent people have better social networks to assist them should sickness occur; socializing may also help delay the onset of dementia. Because the emotionally intelligent get along with various types of people, they may also have a greater willingness to see a doctor and a greater likelihood of heeding the doctor's advice [source: Austin et al..

So there seem to be a few positive links between high emotional intelligence and brain health, but what happens when there's a lack of emotional intelligence? We'll find out if it has any brain effects on the next page.