Grant: CIHR Fellowship

Short-term memory is a core cognitive function for animals. Imagine solving a Rubik cube, we first recognize the configuration of the cube, maintain the configuration in short-term memory while devising a plan, and then carry out the plan seconds later. In our daily lives, maintaining information in short-term memory is important for reasoning, decision making, and motor planning. Although short-term memory is recognized as a critical function in everyday function, and is impaired in diseases such as schizophrenia, how the brain represents and uses short-term memory is not fully understood. Previous studies only examined single brain areas under one task condition and failed to identify a single area that stores short-term memory. Like almost all brain functions, short-term memory is likely maintained in a circuit across multiple regions of the brain, and we require simultaneous measurement from multiple regions to identify the neuronal substrates. The proposed research aims to use new electrophysiology technology to simultaneously record the activity from hundreds of neurons in multiple regions, and perturb the activity to establish function. We propose to study two different behaviors in mice that involve short-term memory. In the first task, mice need to maintain short-term memory during a delay period. We will record and perturb activity across approximately 50 brain regions, selected based on connectivity data. This will generate a complete functional map of neuronal activity underlying short-term memory. In the second task, the mice must route the short-term memory to the upcoming motor plan to correctly perform the task. The second task will allow us to see how the activity map is used in different behavioral context. The successful completion of the map dynamics for short-term memory will guide the development of computer models of the brain and gives a window into the potential dysfunctions that are responsible for cognitive and motor diseases.