Suparna Rajaram, PhD - US grants

The long-term research objectives of this project are: (a) to identify the experimental conditions under which implicit memory for new verbal associations can be developed in normals as well as amnesics, and (b) to specify the cognitive processes that "unitize" or bind the elements of these associations. Two major classes of theories of memory - the systems approach and the processing approach -provide the framework for the proposed studies. In order to understand the conditions and processes that mediate implicit memory for new verbal associations, an experimental analysis of three pivotal issues unexamined in the existing literature is proposed. The first set of studies will examine the role of repetition in binding the elements of the new association at the perceptual level, at the conceptual level, or both. The second set of studies will determine the role of cue constraints in the priming of new verbal associations in amnesia. It is hypothesized here that perceptually constrained cues will be more effective in reducing interference from other responses and in accessing the unitized representations of new associations. The third set of studies will manipulate proactive interference to assess whether new associations in amnesia are perceptual and/or conceptual in nature. Manipulations of these variables will provide converging evidence on the nature of unitization of new associations in implicit memory. Accuracy data in test performance will be collected from three groups of subjects, amnesic patients, matched controls-Implicit, and matched controls- Explicit. These studies are expected to provide mutual knowledge about the functioning of implicit memory in normals as well as amnesics. Specifically, these studies will identify the mechanisms by which new implicit memories may develop in normals when explicit memory contamination is greatly reduced. An understanding of the facilitatory and inhibitory factors in the development of new memories in amnesics has important implications for the management of amnesia.

Three workshops are designed for women in cogntive science, especially those women in the early stages of their academic career. The workshops focus on the grant writing process and will take place at the Psychonomic Society, the Cognitive Science Society, and the Association for Psychological Science. The workshops will take the form of a public forum with invited speaker-panelists to initiate discussion about best practices for the professional advancement of women in cognitive science at the individual and institutional level. By partnering with these established societies, the workshops will maximize the outreach potential to a group that continues to be underrepresented in senior academic positions in the cognitive sciences.

Though the operation of human memory can be understood in terms of processes occurring inside an individual's mind, human memory does not exist within a vacuum--it operates within a larger context of complex social interactions among people. An important question is how social interactions influence memory itself, and likewise, how memory processes influence social interactions. Prior research has established that social interactions among people regarding their shared memories can influence what is remembered by any particular individual involved. In some cases, the result is memory enhancement for the information while in other cases the result is forgetting of the information. The current project will investigate the social transmission of memory and how such transmission shapes the memories shared among individuals as the basis for understanding how social networks influence behavior. Overall, the project will provide insight that will not only increase understanding of the basic operation of human memory, but that will also improve understanding of how behaviors are transmitted within large populations. This work could have important implications for societal issues such as eyewitness memory, educational practice, and how to effectively structure organizations.

To investigate how social interactions influence memory and how these influences affect large-group aggregate behavior, the researchers in the present project will examine the flow of information among individuals. Behavioral experiments will be conducted and used to inform the development of a computational model that in turn will allow rigorous predictions to be made about how information flows within large, realistic social networks. Because the structure of the network becomes increasingly complex as social networks increase in size and because past work has almost exclusively employed small, unstructured groups, the project focuses on the structure of the interactions with a series of studies each investigating an increasingly complex set of social interactions. Each study consists of a behavioral experiment and an analogous agent-based computational simulation. The project will ultimately yield a psychologically plausible model capable of both describing the mechanisms that underlie the social transmission of memory and of faithfully capturing the flow of memory convergence (and divergence) of individuals situated within structured networks. Once realized, this experimentally-validated model will allow collective memory phenomena to be investigated at scales that are not currently feasible in laboratory settings.