When feelings control behavior

Enlarge

Why do we run from one threat but confront another? Why does curiosity propel us forward, while tiredness and hunger sap our drive? Behavior emerges from complex neural processes, as our brains constantly link emotions and internal needs – such as fear and hunger – with external stimuli to decide how we act. This flexibility is at the heart of Anna Schroeder’s research. “Depending on the context, the same internal state can lead to very different behaviors,” explains the Professor of Systemic Neuroscience. “I’m interested in understanding how our brains generate these adaptive behavioral responses.”

In particular, she studies behaviors driven by emotion and motivation, such as defensive responses, feeding and social interaction. Whether fleeing when afraid or eating when hungry, these behaviors are rooted in internal states generated by the brain itself. “These states are important influences on how we perceive the world and respond to it,” says Schroeder. While the brain processes external stimuli such as visual and acoustic signals, internal states simultaneously influence how we perceive and respond to these stimuli, thereby influencing the decisions we make. Schroeder investigates where in the brain these states arise and how they guide the choice between different behavioral alternatives.

Schroeder grew up in New York, and she first encountered neuroscience during her studies in Chicago – initially at the molecular level via biochemistry. “Over the course of my career, my focus has shifted increasingly toward neural circuits and behavior,” she notes.

A mysterious area of the brain

The neuroscientist is particularly interested in an under-researched region of the brain: the zona incerta. “Although the area was given this name – the zone of uncertainty – over a hundred years ago, the name remains remarkably apt because we still know so little about its function,” says Schroeder. Increasing evidence suggests, however, that this region might play an important role in selecting and coordinating behavior by integrating internal states with external sensory information. “Understanding how this mysterious region shapes behavior is one of the main focuses of my laboratory.”

Schroeder and her research group use a broad range of methods to analyze neural circuits at molecular, cellular, and systems levels. She investigates circuit function using techniques such as optogenetics, in which light is used to activate or inhibit specific populations of neurons. Her research is conducted in mice, which provide a powerful model for studying the neural basis of behavior. “Mice display a rich repertoire of both innate and learned behaviors,” she emphasizes, “while also allowing us to study and manipulate defined neural circuits with great precision.” Using techniques such as calcium imaging, she can monitor the activity of neurons in living animals. She then combines these data with detailed behavioral analyses, which she classifies with the help of machine learning.

Prospects for medicine

Schroeder’s research also has a translational dimension, which is important to her: “Many neurological and psychiatric diseases – from anxiety and depressive disorders to neurodegenerative conditions such as Alzheimer’s and Parkinson’s – are associated with changes in internal states,” she explains. A better understanding of neural mechanisms could therefore open up new therapeutic avenues. The zona incerta is already an established target for medical techniques such as deep brain stimulation in Parkinson’s disease patients, even though the underlying mechanisms of action are not yet fully understood. Schroeder hopes her work will help advance existing therapies in targeted ways, or even lead to entirely new treatment strategies.

Beyond her research, she is a strong advocate for women in science. “In my current position, I cannot help but notice that the number of female professors does not reflect the diversity I see in my lectures.” As such, she wants to encourage women to believe in themselves and pursue their path in science. She frequently takes part in events designed to support women in science and is a jury member for the L’Oréal “For Women in Science” awards. “This is a nice opportunity to support truly outstanding female scientists here in Germany and shine a spotlight on their talents,” says Schroeder.

Conveying enthusiasm

Her international career has exposed her to many different scientific and cultural environments, as she recalls: “Academia is demanding and involves long hours, sacrifice, and frequent moving – but it also offers the opportunity to live a dynamic and meaningful life while continuously growing both scientifically and personally.” She fondly remembers the specialized advanced training courses she took during her doctorate, during which she became absorbed in experiments until deep into the night: “After one of these courses, I decided for sure that I wanted to stay in science.”

Schroeder seeks to convey this enthusiasm for science to her students. Her teaching is not just about imparting information; she also wants her students to experience the curiosity and excitement that drive research itself. “Naturally, there are aspects that are challenging – such as when trying to resolve problems with experiments – but the process of problem-solving and discovery is what makes science so rewarding.”