Kelly S. Giovanello - US grants

DESCRIPTION (provided by applicant): This project aims to investigate the status of associative recognition memory in global amnesia in the context of a dual-process model that postulates two separate bases for recognition performance, recollection and familiarity. Four studies will be conducted to examine this issue. The goal of Experiment 1 is to determine whether associative recognition for unrelated word pairs, as compared to single word recognition, is disproportionately impaired in amnesia. Experiment 2 compares associative memory for stimuli in which there is a pre-existing representation of an association (i.e., compound words) to stimuli in which there is not (i.e., unrelated words pairs). Experiment 3 examines whether associative recognition in amnesia is better preserved under the former conditions. Finally, Experiment 4 aims to specify the nature of the familiarity process contributing to amnesics? associative recognition (i.e., conceptual or perceptual) for compound stimuli.

DESCRIPTION (provided by applicant): The proposed project aims to examine the nature of hemispheric asymmetry reductions in older adults during tasks of episodic memory. In the current project, three event-related fMRI experiments are proposed which attempt to characterize the functional mechanisms and cognitive processes mediating age-related non-selective neural activations (i.e. recruitment of brain regions beyond those engaged by young adults). Two views have emerged to account for such age-associated neural activations. By the compensation view, age-related hemispheric asymmetry reductions may help to counteract age-related neurocognitive decline. According to the dedifferentiation view, age-related asymmetry reductions reflect a difficulty in recruiting specialized neural mechanisms. To differentiate between these views, we combine a variety of methods, including between-subjects comparisons, (i.e. high- versus low-functioning older adults), within-subject comparisons (e.g. subsequently remembered versus subsequently forgotten items), and comparisons of conditions which vary in their retrieval demand. In Experiment 1, we attempt to reconcile the results observed in previous episodic encoding studies of aging by combining within- and between-subjects comparisons in a single experiment. In Experiment 2, we explore retrieval-related neural activations in young adults under conditions which differ in retrieval demand. In Experiment 3, we investigate whether age-related non-selective activations extend to medial-temporal lobe (MTL) regions using a task (i.e., associative recognition) that places greater demands on the MTL than tasks previously used to examine this issue.

[unreadable] DESCRIPTION (provided by applicant): Relational memory - the encoding and retrieval of the relations or associations among informational elements - is particularly sensitive to the effects of advancing age. Furthermore, deficits in relational memory are some of the earliest impairments observed in individuals with Alzheimer's Disease (AD). To date, the cognitive processes and neural mechanisms underlying relational memory deficits in aging and AD are poorly understood. Elucidating the neural bases of relational memory deficits should prove useful in understanding differences between normal and pathological aging at very early stages of AD, in subjects with mild cognitive impairment (MCI). Functional neuroimaging studies of healthy young adults suggest that relational memory is mediated by the prefrontal cortex (RFC) and the medial temporal lobe (MIL). Whereas the PFC is thought to mediate strategic processes necessary to encode and retrieve relational information, the MIL is considered to play a critical role in binding or linking together the various cognitive, affective, and perceptual components of a event into an integrated memory trace. Recent data suggest that age-related deficits in relational memory are likely due to declines in RFC-mediated strategic, controlled processing, whereas AD-related impairments in relational memory reflect disruption of MIL binding mechanisms. The central aim of this application is to elucidate the core cognitive processes and fundamental neural mechanisms that give rise to relational memory impairments in aging and early AD. We will utilize anatomically constrained fMRI to assess PFC and MIL activations during memory performance in three groups: young adults, healthy older adults, and subjects who meet criteria for amnestic MCI. The proposed experiments incorporate cognitive paradigms that directly manipulate the contribution of strategic and binding processes to relational memory and then examine the effect on functional neural architecture. As part of the proposed K01 application, the candidate seeks training in: 1) advanced functional MRI techniques, 2) clinical research design, and 3) integration of functional and structural MRI data. The proposed research plan will foster the candidate's development into an independent scientist, using cognitive and neuroimaging methods to study the nature of memory deficits in normal and pathological aging. [unreadable] [unreadable] [unreadable]

The project aims to improve how humans, particularly those with degenerative cognitive conditions or limited cognitive capacities, interact with complex computing or computer-enabled services (broadly called cyber-systems). To advance the state of user interfaces (UI) and create more adaptive interaction modalities, the foundational knowledge regarding human-cyber interaction (HCI) must incorporate more neuro-physiological evidence. The project proposes a three-step plan for attaining this advance. First, three experimental subject groups will be carefully selected and recruited for comparative analysis: 1) healthy and young adults 2) demented or near-demented older adults, and 3) adults suffering from mild brain trauma. Second, experimental sessions will be conducted based on incrementally complex information searching and messaging tasks that require executing the tasks inside an MRI machine.

The goal of the experimental phase is to collect neuronal activation patterns using fMRI, as well as behavioral data associated with response time and accuracy. Third, the experimental findings will be analyzed to establish potential association among neuronal evidence, behavior, and UI performance. The broad technical aim of the initiative is to establish and refine methods for gathering neuro-physiological evidence under complex HCI conditions, and develop new user modeling techniques for supporting flexible and effective interaction. Development of advanced user interfaces capable of monitoring and establishing risk factors associated with impending or existing brain-degenerative conditions is a longer term translational aim. The resources and outcomes produced will be broadly shared among scholars in computer and information science disciplines, with the aim of promoting and supporting training of next-generation HCI researchers.