Investigating Mediodorsal Thalamus Representations Underlying Human Cognitive Flexibility
The goal of this basic experimental research study is to examine how the human thalamus supports flexible thinking and behavior. Specifically, the research aims to elucidate how the mediodorsal (MD) thalamus encodes and updates context-the mental framework that determines which rules or actions are relevant in a given situation. This work may contribute to understanding why certain psychiatric conditions, such as schizophrenia and ADHD, involve difficulties with cognitive flexibility and control. The primary research questions are: Does the MD thalamus represent the context that organizes how working memory guides task selection? Does the MD thalamus signal when context needs to be updated after a change in task demands? Do these thalamic representations support generalization to new situations or rules? Participants will complete cognitive tasks while undergoing high-resolution brain imaging using 7-Tesla MRI. The investigators will combine behavioral data, computational modeling, and advanced neuroimaging analyses to examine how the thalamus interacts with the cortex during flexible decision-making.
• No history of any neurological, psychiatric, or medical condition that could affect cognition
• No use of benzodiazepines, long-acting opioids, or other psychotropic drugs that could alter cognitive performance
• Normal or corrected-to-normal vision (visual acuity)
• Normal color perception (Farnsworth-Munsell 100 Hue Test)
• Fluent in English
• No metal implants (including aneurysm clip, cardiac pacemaker, ICD, IUD, neurostimulation system, spinal cord stimulator, internal electrodes or wires, bone stimulator, ear implant, insulin or other infusion pump or device, prosthesis, artificial or prosthetic limb, shunt, vascular access port or catheter, thermodilution catheter, medication patch, radiation seeds or implants, wire mesh implant, tissue expander, surgical staples or clips or sutures, joint replacement, joint/bone pin/screw/nail/wire/plate, dentures, or non-removable hearing aid)
• No exposure to shrapnel or other-related MR contraindications
• No non-removable body piercing jewelry
• No non-removable makeup
• No history of claustrophobia
• No history of breathing problems
• Not currently pregnant or trying to get pregnant (this will be determined via self report and no records will be kept).