Project Summary/Abstract A central issue in the research of memory is how the brain integrates information available in the environment with our prior knowledge from past experiences to facilitate memory formation and retrieval. The current project approaches this issue by examining how perceptual features and prior knowledge contribute to the likelihood that a stimulus can be remembered by any given observer, a phenomenon often attributed to stimulus memorability. The long-term goal of this project is to foster the applicant’s development as an independent investigator focused on the mechanisms of memory formation and retrieval to develop mechanism-based interventions for memory deficits in aging and cognitive diseases. The overall objective of this project is to elucidate how prior knowledge contributes to stimulus memorability by allowing the applicant to obtain further training in memory research at the NIH based on computational modeling of large-scale behavioral data (with Chris Baker) and analyses of fine-scale neural data (with Kareem Zaghloul). In contrast to the traditional view that memorability is merely a perceptual attribute of stimuli irrespective of observers’ prior knowledge, the central hypothesis of this proposal is that prior knowledge represented in semantic imbued brain regions, such as the anterior temporal lobe (ATL), makes remembering more likely irrespective of stimulus perceptual features processed in inferotemporal regions. The rationale for this project is that determining the mechanisms for memorability will inform how memory is efficiently formed and retrieved, thereby improved diagnoses and interventions for memory deficits can be developed. Meanwhile, this project will also provide the applicant with the means to establish early research independence. The central hypothesis will be tested with these specific aims: 1) Specify how semantic features contribute to stimulus memorability (K99); 2) Characterize fine-scale neural mechanisms underlying semantic contributions to stimulus memorability (K99-R00); 3) Manipulate memorability via training and brain stimulation (R00). Based on large-scale behavioral data, Aim 1 will model and isolate the contributions of semantic features to the memorability of scene images, where both perceptual and semantic features are available to support memory. Aim 2 will use multi-level direct recording of temporal lobe activity in humans to determine how the ATL underlies semantic contributions to stimulus memorability. Aim 3 will investigate the causal relationship between prior semantic knowledge and memorability via behavioral training and electrical stimulation over the ATL. This project is innovative because it will establish a novel neurocognitive mechanism for memorability driven by prior semantic knowledge using innovative tools that address the limitations inherent to other methods. This project is significant because it will ultimately have a positive impact on promoting better...