Department of
Psychological and Brain Sciences

Wei Tang’s studies of how the brain detects and interprets statistical patterns have implications for understanding mental health.

PBS Professor Wei Tang began her journey into neuroscience growing up among the lush, karst landscapes of Guilin, a city in southeastern China near the border of Vietnam. Known for the scenic beauty of its waterways, caves, and mountains, Guilin draws visitors from around the world. “I encourage you to look up some photos,” says Tang. And the advice is well
worth taking.

In that sublime natural setting Tang first became fascinated by “what makes all this life happen.” In school she gravitated toward physics and biology, majoring in biology as an undergraduate. Yet she soon became aware that the curriculum, which included the study of all forms of life and systems of the body, had one glaring absence: It did not include study of the brain. At the time, she explains, neuroscience was a separate discipline in China, which you could only study at the graduate level.

Current directions

Today Tang’s work seems to reflect that unsated curiosity about how the brain fits into the biological world. At the broadest level, she aims to understand how the brain learns statistical patterns from the environment. “Our brain is equipped with the ability to pick up those patterns, even without our attention. I want to understand how it does that,” she says. Behaviorally, we take advantage of those patterns by forming habits, which allows us to reserve our cognitive resources for more complex or urgent tasks. At the same time, we also need to know when to deviate from those habits under changing circumstances. “So the system,” she explains, “has to have a mechanism that determines when it’s best to follow your habits and when to switch away to achieve specific goals or to confront unusual circumstances.”

Central to this process are two specific brain regions, the hippocampus and the basal ganglia, the white matter connections between them, and their communication with each other and with other cortical regions. As she explains, the hippocampus learns to represent associative patterns through repeated experience, while the basal ganglia functions as the “gate” for actions and deciding among possible choices which action to take at any given moment. Analyzing how these two regions work together and how white matter channels information between them and other brain regions is a key challenge of her work. It may also offer a new framework for understanding various psychiatric disorders, among them addiction, depression, and obsessive-compulsive disorder.

So far, Tang’s work has been focusing on the role of the hippocampus in the learning process in experiments that observe both behavior and brain activity. First, she and her colleagues engaged research participants in a task asking them to look for a particular target in a sequence of images. The researchers manipulated the structure of the sequence in a way that will determine whether the participants are sensitive to temporal patterns. They then used both functional MRI to investigate brain activity and diffusion MRI to map out structural features in and around the hippocampus, in particular the white matter pathways on which information travels. “We have finished all the data collection. We’ve got convincing results that the hippocampus plays an active role in learning rather than being a passive storage of temporal patterns. We are preparing a manuscript to report this finding.”

Meanwhile, Tang is exploring the process of how the brain chooses to follow or change course with respect to habits and goals, focusing on the function and structure of the basal ganglia. Again, she is planning two sets of experiments, one that gauges participants’ decision-making behavior, followed by analysis of brain activity and structure using functional and diffusion MRI. Tang is also happy to have the assistance of undergraduate students from the Early Research Experience Program in the Hutton Honors College. Together they are developing a computer game for study participants that is designed to help the researchers uncover the decision-making process they believe is centered in the basal ganglia.

Clinical implications + the role of anatomy

Tang’s work also has implications for clinical psychology. By identifying how systems for detecting statistical patterns, forming habits, and goal-switching are supposed to work, she also contributes to the understanding of what happens when they fail us.

Tang notes, for example, that addictive behavior indicates a deficit in our ability to change our behavior. It’s a “deficit in the ability to make new, adaptive choices, especially under stress and craving, such that the goal-directed system cannot override the tendency to go back to a particular choice, such as taking a certain substance.”  Likewise with depression. “Depression is a mood disorder. But there are elements such as rumination, which could be seen as a habit of going back to negative, self-focused thought. It’s the loss of ability to deviate away from the negative thoughts that could be considered a certain type of emotional habit,” she explains. And in the case of obsessive-compulsive disorder, you keep trying to achieve a goal, which you do not think you ever reach. Someone who repeatedly washes their hands, for example, does not believe they have ever reached the goal of getting them clean. A deficit in the circuitry of this system prevents them from seeing the goal as being achieved.

One of the qualities of Tang’s work which distinguishes it from other work in the field is her emphasis on studying the function and structure of the brain together. “Anatomy tells us a lot. Just think, whether two big systems are connected or not will fundamentally change your hypotheses about where information is routed. When you look at the brain anatomy, it’s a biological network. It has to have all these constraints such as energy efficiency built into it. It has to have an evolutionarily advantageous topography, and this topography provides us critical insight into how information can be
gated, integrated or diffused behind an
observed behavior.”

Integral to the biological systems and environment that surround it, the brain, as it is represented in Tang’s work, seems more than ever an inextricable feature of the biological world, as if she is continually in search of the missing link in her early biological studies.

Academic + other journeys

After receiving a B.S. at Nanjing University in biological science, Tang received a Ph.D. from Florida Atlantic University in complex systems and brain sciences. She received postdoctoral training at Massachusetts General Hospital/Harvard Medical School in MEG analysis for dynamic brain networks and at University of Rochester and McLean Hospital/Harvard Medical School for translational neuroanatomy and dMRI tractography. She joined IU Bloomington in 2020 as an assistant scientist in the Luddy School of Computing, Informatics and Engineering in the Department of Computer Science before joining PBS in the fall of 2025.

She also returns each year to her family and friends in Guilin.