Our research is focused on how the brain supports learning, memory and decision making in humans.
We adopt an integrative approach that draws broadly on neuroscience to make predictions about cognition, and combine functional brain imaging (fMRI) with behavioral, pharmacological and patient studies in humans.
Brain imaging tells us about the spatial and temporal characteristics of neural mechanisms involved in learning. Patient studies augment this approach and provide direct evidence of the necessity of a brain region for specific cognitive processes. Converging evidence from these complementary approaches produces a fuller picture of the cognitive and neural processes involved, and necessary, for different aspects of learning.
We focus on the investigation of brain systems that underlie different forms of learning. Our work addresses four central questions:
How do multiple brain systems interact?
We are interested in characterizing when and how different brain systems for learning interact and whether this interaction is competitive or cooperative. We focus on two main brain systems for learning - one in the striatum and the other in the hippocampus. Traditionally, the striatum and hippocampus were thought to support independent and distinct learning systems. We have demonstrated that there is cross-talk between these systems during learning, raising questions about the nature of this interaction and its significance for learning and decision making. We are now investigating how this cross-talk is impacted by several key factors, including: motivation and feedback, social context of learning, ageing, and genetic differences between learners.

How does dopamine modulate learning in humans?
Dopamine is thought to play a key role in motivation, affect and learning. We are interested in understanding how dopamine modulates learning in both the striatum and the hippocampus. Dopamine neurons project directly to the striatum and the hippocampus and dopamine plays an important role in modulating plasticity in both regions. We are conducting studies to understand what the implications are for how people learn, what they remember, and how learned experiences guide decisions.
To understand how dopamine modulates learning, we are looking at how changes to dopamine levels impact learning and decision making. We do so by looking at behavior in diseases that affect dopamine
transmission (such as Parkinson's disease and schizophrenia), by manipulating dopamine levels in healthy people (pharmacologically), and by linking individual variability in dopaminergic transmission to variability in behavior (genetics).


How does brain development impact learning and decision making in kids and teenagers?
We are working to characterize the developmental trajectory of different forms of learning (e.g. implicit vs. explicit) and how they relate to developmental changes in the striatum, the hippocampus and their dopaminergic inputs. We are especially interested in brain development during adolescence and how it relates to both adaptive and maladaptive behaviors during this phase of development - both in the laboratory and in the classroom.
Adolescence is characterized by changes to dopaminergic processes and to the function of the striatum. We are interested in learning more about how the balance between multiple brain systems is impacted by adolescence and what this reveals for
understanding adaptive and maladaptive behaviors during this phase of development, both in the laboratory and in the classroom.


What are the broad implications of our science?
Health
Much of our research takes place in individuals with neurological or psychiatric disease, including Parkinson's disease and schizophrenia. We aim to build on our empirical and theoretical work on the brain mechanisms underlying learning, memory and decision making to advance understanding, and possibly treatment, of cognitive and affective symptoms in neurological and psychiatric disease.
Education
Understanding how learning takes place in the brain has important implications for educational practice and policy. Linking basic science to the classroom is challenging. Our developmental studies aim to start laying the groundwork towards this effort. In parallel, we are talking to educators to try to develop a common language and start building the bridges that will allow translation of neuroscientific findings to education.


What are our tools?
Our brain imaging studies take place at the Columbia University Medical Center in the department of Neurology, at 168th St. and Fort Washington. We use functional magnetic resonance imaging (fMRI): a non-invasive method for measuring changes in brain activation that are related to mental processes. Participants in our brain imaging studies lie in a scanner while they play computer games which we design. This allows us to examine what is happening in the brain - and where precisely it is happening - while people learn information and make decisions.

Our patient studies and behavioral studies of cognition take place in our laboratory, located in Psychology Department on the Morningside Heights Campus of Columbia University, near 119th Street and Amsterdam. Participants in these studies sit at a desk in a quiet room and play computer games that involve learning information and making decisions. Participants are individuals of a variety of ages, from 6 to 80, including people who are healthy or who have a specific neurological or psychiatric condition.

If you are interested in reading more about our studies, check out some of our recent papers by clicking here. If you are interested in participating in a brain imaging study, email us.