THIS IS A CONTINUATION OF N000141510033 Decoding and Enhancing Neural Mechanisms for Episodic Memory

Abstract

Research on learning and memory is fundamental to understanding cognition and directlyrelevant to the training of military personnel and to the diagnosis and rehabilitation of injuredsoldiers. Functional magnetic resonance imaging (fMRI) studies of memory have identified acortico-hippocampal network that is critical for remembering past events. Recent evidenceindicates that regions in this network generate rhythmic electrophysiological oscillations in thetheta band (4-8 Hz), and that theta oscillations may be related to cognitive states that promotesuccessful memory retrieval. The objective of this project is to use three empirically motivatedmethods to manipulate theta activity and determine effects on memory and on recruitment ofbrain networks measured with electroencephalography (EEG) and fMRI. Rhythmic sensorystimulation (Aim 1), transcranial alternating current stimulation (Aim 2), and reward motivation(Aim 3) will be used to manipulate theta activity during memory retrieval tasks. EEG studies willdetermine how theta enhancement affects the magnitude and timing of theta activity duringmemory retrieval, and fMRI studies will determine effects on recruitment of the corticohippocampalnetwork. We will also use advanced multivariate analysis techniques to decodehow information about past episodes is represented in neural activity patterns and test whethertheta enhancement sharpens these representations. This project will advance basic science bydirectly connecting neural oscillations, which are currently poorly understood, to specificcognitive processes and to activity in a cortico-hippocampal network that is thought to play acrucial role in episodic memory. Moreover, the proposed studies can lead to the development ofnovel biomarkers for memory function and dysfunction (e.g., to assess service-connectedcognitive impairment) and of systems for accelerating learning (e.g., in training situations) andrehabilitating memory (e.g., in injured soldiers). The work can also contribute to thedevelopment of memory-guided brain-computer interface technologies.

Document Details

Document Type
DoD Grant Award
Publication Date
Aug 12, 2016
Source ID
N000141612511

Entities

People

  • Charan Ranganath

Organizations

  • Office of Naval Research
  • United States Navy
  • University of California, Davis

Tags

Fields of Study

  • Psychology

Readers

  • Neuroscience
  • Traumatic Brain Injury (TBI) and Cognitive Aging in the Guam and Border Populations Affected by Alzheimer's Disease and Tau-Associated Dementias.