Research

At the Bakkour Lab, we investigate how the human brain uses memory and learning to guide everyday decisions. Using a combination of cognitive neuroscience tools — including fMRI, eye tracking, and computational modeling — we explore the computations that support decision-making. Our research focuses on how past experiences shape expectations, how new information updates those expectations, and how these processes work together to influence decisions. By studying the interplay between learning and memory, we aim to uncover fundamental mechanisms that drive human cognition. Read more about our ongoing work below!

Reward, False Memory and Choice Preference

Our memories play a crucial role in many decisions, but memory is not infallible and can get distorted. Understanding the impact of a fallible memory system on decision-making is essential. To explore how rewards influence memory and subsequent choices, we employed a modified version of the classic Deese-Roediger-McDermott (DRM) paradigm (Deese, 1959; Roediger & McDermott, 1995), where we assigned different levels of reward to different DRM lists at the encoding stage. Across two experiments, we aim to test our prediction that reward distorts memory representations that are later relied upon during value-based decisions. This study is being led by Xinyue Li.

Preprint

Inductive Biases for Predictive Learning in Complex Environments

To make the best decisions, humans must predict how our actions may affect future events. However, given that everyday experiences involve numerous elements interacting in complex ways, it is not trivial to extract information that is relevant for these inferences. How does the mind and brain solve this problem? This project characterizes the role of inductive biases in constraining learning towards relevant causal information. Specifically, we investigate semantic bias, whereby learning is directed towards associations between our experiences that reflect our existing semantic knowledge. This work uses a combination of computational modelling, behavioral experiments, and fMRI to develop a holistic theory of this mechanism from behavior to brain. This study is being led by Euan Prentis.

The Effect of Reward on Existing Cognitive Maps

While experienced as discrete events, memories tend to form networks to allow for adaptive behavior. These networks, also known as cognitive graphs, are internal models that represent relations between prior experiences and have been used to examine how flexible decisions are made, such as how their structure can bias choices. However, memory is not static and external factors like reward are known to influence decisions by prioritizing items in memory that are directly or indirectly associated with it. The potential for reward to alter existing cognitive graphs and the impact of such alteration on decision-making is crucial for understanding how choices are made. Thus, three experiments were conducted to investigate how reward and the structure of the cognitive graph (a community structure) interact and influence decision-making. This study is being led by Seoyoung Lee.

The “Battleship” Project

Rewards, such as money or juice, are powerful drivers of learning and memory-guided decision-making. However, some populations, including older adults and Parkinson’s Disease (PD) patients, face challenges in reward-based learning. Yet, both rewards and information can uniquely drive learning, and our lab’s previous work has shown that older adults can learn faster than young adults when provided with both feedback types. To explore dopamine’s critical role in this process ─ given its known involvement in reward learning and its decline with aging and in PD ─ we are collaborating with Dr. Mahesh Padmanaban at UChicago Medicine’s Parkinson’s Disease and Movement Disorders Clinic. This study examines how PD patients, both on and off dopaminergic medication, learn from reward and information cues. By investigating these dynamics, we aim to test the role of dopamine in information search, uncover mechanisms underlying enhanced learning in older adults, and illuminate the interplay between dopamine, aging, and learning strategies. This study is being led by Abby Hedden.

Anorexia Nervosa Value Construction

Anorexia Nervosa (AN) is a serious psychiatric illness characterized by restriction of energy intake, maintenance of a significantly low body weight, and disturbances in body image. AN has the second highest mortality rate of any psychiatric illness, yet, there are currently no evidence-supported treatments for AN for older adolescents and adults. Furthermore, little is known about how patients with AN construct the subjective value placed on food and how this process leads to maladaptive food choice. It is also not well understood why it is so challenging for individuals with AN to change the foods they choose to eat in order to recover from the disorder. In collaboration with Dr. Jennifer Wildes, this study investigates the cognitive and neural mechanisms that underlie food value construction that drive maladaptive food choices in individuals with AN using a multi-attribute decision task, fMRI, eye-tracking, and computational modeling. In a second part of this study, we will examine how the food value construction process can be altered. This study is funded by the NIMH and is being coordinated by Sammi Weiss.

Reward-induced Memory Precision Bias

Extensive evidence suggests that rewards motivate individuals to better remember studied items, enhancing the accessibility of memories, as evidenced by improved recognition and recall rates. Additionally, rewards influence the neural representation of memories, leading to increased similarity among items associated with rewards. This phenomenon, while bolstering memory accessibility, may paradoxically result in a loss of specific memory details. By examining the interplay between reward and associative memory, the project seeks to deepen our understanding of these dynamics, particularly how rewards affect the precision of memory details. This study is being led by Xinyue Li.

Curiosity and Choice Preference

Curiosity enhances memory not only for high-curiosity stimuli but also for neutral stimuli presented alongside high-curiosity stimuli (i.e., incidental stimuli). Moreover, people tend to prefer familiar, or better remembered, objects over unfamiliar ones ─ a phenomenon called the “mere exposure effect”. This study bridges these two concepts to investigate how curiosity shapes our preferences for neutral, incidental stimuli. By examining the interplay between value-associated cues (i.e., curiosity), memory, and decision-making processes, this research seeks to broaden the field’s understanding of how curiosity shapes and drives cognitive processes. This study is being led by Abby Hedden.

The Interplay between Stress, Prospection, and Intertemporal Choice

Various factors can influence whether we choose a smaller, immediate reward or a larger, delayed reward – a decision known as intertemporal choice. Research shows that imagining the future (i.e., prospection) can reduce the tendency to discount future rewards, whereas acute stress increases discounting, making individuals more likely to favor immediate rewards. Given these opposing effects, our study investigates how prospection and stress interact and, in turn, affect intertemporal choice. To examine this relationship, we induced stress and recorded electrocardiogram data during a modified intertemporal choice task. This study is being led by Seoyoung Lee.