By analyzing electrical brainwaves, a team of scientists from Texas has found that depressed people are drawn to negative information in a way that non-depressed people are not. Their new findings are published in Biological Psychology.

“We knew that past research has demonstrated a link between making decisions about whether words are self-referential and mood, and that there appear to be consistent patterns in how the brainwaves of individuals with major depression respond to that decision-making,” explained study author Justin Dainer-Best of the University of Texas.

“The field is moving towards data-driven psychology, and we continue to search for the mechanisms driving major depression. We think that replicating and pushing this work further is important for understanding which markers and mechanisms are worth targeting in interventions.”

The researchers used electroencephalography (EEG) to compare the brain activity of 22 adults with Major Depressive Disorder to a control group of 24 healthy adults. The participants viewed positive and negative words on a computer screen and made rapid judgments about whether the words described them.

As previous research has found, depressed participants were more likely to say that the negative words described them. But the researchers found this was reflected in their brain activity as well.

The EEG recordings indicated that negative words captured the attention of depressed participants to a greater degree than positive words during the later stages of information processing.

“The key here is really that last point in the highlights — ‘Sustained attention for negative stimuli may be an important target for depression interventions’,” Dainer-Best explained to PsyPost.

“Putting that another way, we found that adults who were depressed were drawn to negative information in a way that those who weren’t depressed were not, and this was apparent not just in how they responded to the task but in their EEG as well. This is promising for future treatment research.”

Dainer-Best noted that future research on this topic would benefit from larger sample sizes.

“This is a small study, and while it replicated some previous research, there were some differences in the results that weren’t simply driven by our analytic techniques,” he said. “I think the real proof of these results will come when we have a treatment study that shows these EEG differences before treatment, and their amelioration after treatment.”

The study, “Sustained engagement of attention is associated with increased negative self-referent processing in major depressive disorder“, was also co-authored by Logan T. Trujillo, David M. Schnyer, and Christopher G. Beevers.