Research

Memory

The MDRC is dedicated to the study of memory disorders and their cognitive and neural underpinnings in brain-injured adults. Our research involves a number of different approaches.

First, we conduct cognitive behavioral studies of explicit memory and implicit memory with the goal of identifying component processes contributing to memory functioning. In the domain of explicit memory, we use dual process models of recognition memory as a theoretical framework for contrasting amnesics’ performance on recall and recognition tasks, as well as their performance on tasks of item and associative memory. Our studies of implicit memory examine boundary conditions of intact priming in patients with memory disorders and explore the contribution of different forms of explicit retrieval to performance on implicit memory tasks.

Second, we study classical conditioning in amnesia as a simple model of associative memory. Because the neural basis of such learning has been well characterized in animal research, this paradigm provides a unique way to explore the contribution of the medial temporal lobes to memory.

Third, we use functional imaging techniques in normal individuals and in patients with amnesia to address hypotheses about the nature of the neural circuits mediating component processes, as well as the time course of those processes.

Finally, in a more clinical vein, a number of studies aim to understand the heterogeneity among patients with a similar etiology, by considering specific anatomical and cognitive factors that may affect patterns of recovery.

Mild Traumatic Brain Injury

The MDRC has also recently undertaken some studies involved in the investigation of the neural and cognitive outcomes of mild traumatic brain injury (mTBI). With the increasing use of improvised explosive devices (IEDs), blast mTBI  has become the signature injury of the Operation Iraqi Freedom (OIF)/  Operation Enduring Freedom (OEF) wars. We have designed a study to  investigate white  matter abnormalities and the functional significance of microstructural damage within the  veteran blast-induced mTBI population. Ultimately, we hope to uncover optimal neural  predictors of current and persisting cognitive impairments. Individuals will also be enrolled in our behavioral study, which is designed to explore the neuropsychological and functional  outcomes of mTBI. Participants will be given a variety of behavioral tests to measure varying cognitive capabilities. Together, these studies will help unravel the neural and cognitive underpinnings of mTBI.