Characterizing neural mechanisms of cognitive control

Duke University, Durham NC

Investigators

Linked publications & trials

Abstract

DESCRIPTION (provided by applicant): The overall purpose of our research program is to understand the brain mechanisms of cognitive control, the ability to flexibly adapt thoughts and behavior in line with internal goals. Work in the previous grant period has focused on how conflicts in information processing (e.g., uncertainty over how to best steer into your intended lane at a busy intersection) can lead to an immediate re-focusing of attention on the task at hand (conflict- control). In this renewal application, we ask broadly: what happens the next time you approach that intersection? Will you remember your previous difficulties and approach it with a heightened focus of attention to start with? This type of interaction between cognitive control and memory processes pervades our daily lives, and a failure to appropriately match situational demands with attentional states is a key feature of many debilitating psychiatric disorders, such as schizophrenia. However, how associations are formed between cues (e.g., the intersection) and appropriate control states, and what the consequences are of different control operations for subsequent memory, is presently poorly understood, owing in part to control being defined historically in opposition to well-learned responses (will vs. habit). Therefore, the goal of this proposal is to characterize the interaction of cognitive control and associative processes in order to improve current models of how the brain supports adaptive behavior, and to enable new approaches for understanding failures of cognitive control in the clinical domain. To this end, we examine control-memory interactions from two directions: first, specific aim 1 investigates how learning drives the allocation of cognitive control. In other words how does the busy intersection become associated with a heightened control state? We use computational modeling, fMRI, and fMRI-guided TMS approaches to characterize how the brain learns to adapt control settings to changing demands (study 1), and to directly contrast the neural mechanisms that link cues to control states (context-control learning) with those supporting classic stimulus-stimulus and stimulus- response learning (studies 2 and 3). Second, specific aim 2 characterizes how cognitive control processes affect memory. E.g., are you more likely to remember key details about the intersection after you had to overcome difficulty there? Specifically, we will assess the impact of three crucial cognitive control operations (conflict-control, updating, and response inhibition) on memory encoding, by having participants perform these operations on different stimuli and subsequently testing their recognition of these stimuli i surprise memory tests (studies 4-6). Pairing this approach with fMRI allows us to parse the brain mechanisms that link specific control operations to memory by contrasting the neural signatures of successful (subsequently remembered) vs. unsuccessful (subsequently forgotten) encoding of task-relevant and task-irrelevant stimuli as a function of control state. This innovative projec is set to significantly improve our understanding of how the human brain facilitates context-sensitive, controlled behavior, and to gain insight into how this ability may fail.