Teens with depression show unique eye movement patterns linked to memory and attention problems

A new study published in Psychiatry Research: Neuroimaging has found that adolescents with major depressive disorder display unusual eye movement patterns, which are linked to cognitive problems such as memory and attention deficits. The researchers used eye-tracking technology to compare the visual behavior of adolescents with and without depression during different visual tasks. They found that certain eye movement characteristics were significantly different in adolescents with depression and were associated with poorer performance on cognitive tests.

Major depressive disorder often begins during adolescence, a period of intense emotional, social, and cognitive development. Depression in teenagers is not only becoming more common but also tends to recur and interfere with many areas of life, including school, family relationships, and social functioning. In many cases, even when mood symptoms improve with treatment, cognitive difficulties—like trouble with memory, attention, and understanding social cues—can persist. These problems can make it hard for adolescents to return to normal daily activities and may contribute to poor treatment outcomes and higher relapse rates.

In recent years, researchers have become interested in using eye-tracking technology as a non-invasive way to study how the brain processes information. Eye movements, including how often people look at certain parts of an image or how well they can follow a moving object, are known to reflect underlying cognitive processes. For example, smooth and coordinated eye movements require good attention control, while frequent or erratic eye movements might indicate difficulty with focus or information processing. Since brain areas involved in eye control also play a role in cognitive functioning, the researchers wanted to explore whether eye movement patterns could serve as indicators of cognitive problems in depressed adolescents.

The study was carried out by researchers at Central South University’s Second Xiangya Hospital in China. They recruited a total of 113 participants aged 12 to 17 years. Of these, 71 had been diagnosed with major depressive disorder, while the remaining 42 were healthy adolescents with no psychiatric conditions. All participants had normal or corrected-to-normal vision, and those with other medical or neurological issues were excluded. The researchers collected demographic information, assessed depression severity using standardized questionnaires, and evaluated cognitive performance using a battery of neuropsychological tests.

Cognitive testing included measures of memory, attention, language, and social reasoning. For example, the Children’s Depression Inventory and the Hamilton Depression Scale were used to evaluate mood symptoms, while the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) measured various areas of cognitive functioning. Social cognition was assessed using a test designed to measure the ability to detect social blunders, known as the faux pas test.

Eye movement data were collected using a high-precision eye tracker that monitored the dominant eye while participants completed two tasks. The first was a free-viewing task, in which participants were shown a series of neutral images—such as landscapes and geometric shapes—for eight seconds each. The second was a smooth pursuit task, which involved tracking a dot moving in a complex sinusoidal pattern across the screen. The researchers measured various aspects of eye movement, including how many times participants looked at different parts of the image (fixation count), how long their eyes remained still (fixation duration), and how fast and far their eyes moved (saccade measures).

When comparing the groups, the researchers found several differences in both cognitive functioning and eye movement patterns. Adolescents with depression scored significantly lower on overall cognitive performance, particularly in areas related to immediate memory, attention, and delayed memory. They also performed worse on the faux pas test, suggesting difficulties in understanding social situations.

In the free-viewing task, the depressed group showed a smaller average saccade amplitude, meaning their eye movements covered shorter distances as they scanned the images. This could indicate a more restricted or cautious visual exploration pattern. In the smooth pursuit task, which tests the ability to follow moving targets, the depressed group showed more frequent fixations and saccades. These patterns suggest that they may have had difficulty smoothly tracking the moving object and had to compensate with more frequent adjustments.

The most interesting part of the study came from the correlations between eye movement variables and cognitive test scores. In the group with depression, some specific eye movement characteristics were linked to better or worse cognitive performance. For example, more frequent fixations were associated with better immediate memory, while longer fixation durations were linked to poorer memory. Faster eye movements and longer saccade durations were connected with better attention and memory. One measure—the number of saccades in a complex background tracking task—was also positively associated with better performance on the faux pas test, suggesting that how adolescents scan visual scenes may reflect how well they can understand social situations.

These associations were not observed in the healthy group, indicating that the eye movement patterns seen in the depressed group may reflect compensatory strategies or underlying difficulties specific to the condition. For instance, adolescents with depression may rely on faster or more frequent eye movements to make up for cognitive limitations, particularly in tasks that require sustained attention or memory encoding.

The study adds to growing evidence that eye-tracking can serve as a useful tool for understanding how depression affects the brain and behavior. It also highlights the potential for using eye movement data as part of clinical assessments, especially for detecting subtle cognitive deficits that might not be apparent through traditional interviews or questionnaires.

However, the study has several limitations. All of the participants with depression were already receiving treatment, so it is unclear how medications may have influenced their cognitive functioning or eye movements. The groups also differed in age and gender distribution, which could affect the results. Additionally, the tasks used were relatively simple and involved neutral images, which might not fully capture how adolescents with depression respond to more emotionally charged or socially complex situations. The cross-sectional design also limits the ability to determine whether eye movement abnormalities cause cognitive problems, result from them, or develop alongside them.

The researchers suggest that future studies should explore these relationships using more varied tasks, longitudinal designs, and possibly treatment-naive patients. They also emphasize the need to refine eye movement tests to better capture the unique features of adolescent cognitive development.

The study, “The association between eye movement characteristics and cognitive function in adolescents with major depressive disorder,” was authored by Yuanyuan Lu, Lintong Song, Chunxiang Huang, Tianqing Fan, Jinqiao Huang, Leyin Zhang, Xuerong Luo, Yanhua Li, and Yanmei Shen.