Ayanna K. Thomas - US grants

DESCRIPTION (provided by applicant): This proposal is written in response to PAR 03-056 and focuses on research topic number 16 (Executive Function). Metamemory is traditionally defined as the knowledge and awareness we have about our own memory. Metamemory focuses on the interplay between monitoring our mental state and controlling our cognitive processes. Awareness of our memory capabilities allows us to implement strategies to better remember events. Metamemory failure in people with Alzheimer's disease (AD) can influence episodic memory through the failure to allocate resources during study or the failure to reject possible competitor items at test. To further investigate metamemory in people with AD, a judgment-of-learning (JOL) procedure is adopted in which participants are asked to judge how easy it will be to remember an item immediately after studying that item. Researchers have proposed that JOLs are influenced by three classes of cues: intrinsic, extrinsic, and mnemonic. Intrinsic factors include item properties; extrinsic factors pertain to the encoding operations applied by a learner; mnemonic factors include idiosyncratic knowledge about one's own memory. These factors will be examined in detail to determine what cues lead to the most accurate metamemory performance. Further, the proposed research examines whether the deficit in episodic memory JOLs is reliably related to impaired executive functions as assessed through psychometric measures that have been localized to frontal and medial temporal regions. Three experiments manipulate intrinsic, extrinsic, and mnemonic cues independently. Memory accuracy will be compared to JOLs using Goodman-Kruskal gamma (y) correlations and absolute calibration. Metamemory accuracy will be correlated to psychometric measures in order to assess the neurological underpinnings of metamemory deficits. Results from this research will foster the development of a larger federal grant proposal which will investigate how reliance on metamemory can be used to improve episodic memory in people with AD.

Faulty eyewitness reports have contributed to approximately 70% of wrongful convictions in the United States (Innocence Project, 2016). What gives rise to such faulty reports? Research has revealed that eyewitness memory can be contaminated by false or inaccurate information (misinformation). Exposure to misinformation can occur through the course of interviews and questioning, discussions with co-witnesses, or from information garnered from the media and other external sources. Given that these are the circumstances routinely faced by eyewitnesses, it is imperative that researchers understand how to mitigate susceptibility to misinformation so that such memory errors can be avoided. This project aims to identify a resource-minimal, evidence-based practice that can be employed to protect the integrity of eyewitness memory reports. The research will focus on the effects of warning eyewitnesses about the threat of misinformation. Warnings have previously been incorporated into other areas of legal practice with great success. For example, the Department of Justice (1999) recommended that law officials warn eyewitnesses that a guilty suspect may not be present prior to conducting a lineup -- a practice that significantly reduces false identifications. By 2013, approximately 90% of surveyed police departments adopted this practice. The current project uses a cognitive and neural approach to test whether a similar practice can reduce faulty eyewitness reports. The research team will disseminate the results through seminars with local legal communities to assure the impact of this research on the public.

Research reveals that memory errors can be reduced when eyewitnesses are warned that external sources can contaminate memory for an event. For example, when warned about the veracity of information given to an eyewitness after an event, participants were less likely to incorporate such information into memory reports. However, providing a warning after exposure to false or inaccurate information (misinformation) does not entirely eliminate misinformation errors. Is there an optimal time to warn eyewitnesses? Experiment One will reveal the most effective time to warn eyewitness about the threat of misinformation. Such evidence will be especially useful to the legal community. Despite a bulk of research on warning in the context of misinformation, no study has used neuroscientific methods --thus, how warning modulates neural activity to protect memory remains unknown. Accordingly, Experiment Two will employ functional magnetic resonance imaging (fMRI) to examine the manner in which warning modulates neural activity to ultimately reduce eyewitness memory errors. This experiment will directly enhance our understanding of the complex mechanisms that support human memory processes in the context of the eyewitness. Lastly, it is noteworthy that misinformation errors that are induced by repeated interviewing have been observed even under optimal conditions for learning and memory. Thus, the inherent stress experienced by eyewitnesses -- from the onset of the witnessed event, during the retrieval of such events, and extending to courtroom testimony -- may pose an even greater risk for memory errors. For this reason, Experiment Three will assess whether warning can reduce eyewitness susceptibility to misinformation under conditions of stress.