Neural Mechanisms of Cognitive Control in Posttraumatic Stress Disorder

Emory University, Atlanta GA

Investigators

Linked publications & trials

Abstract

DESCRIPTION (provided by applicant): Attentional disruptions are among the most commonly-reported and impairing symptoms of Posttraumatic Stress Disorder (PTSD). These problems may reflect abnormalities in cognitive control, a construct characterized by an individual's ability to effectively, and efficiently, manage distracting, emotionally-salient information while they engage in a cognitively-demanding task. Presently, the precise nature of cognitive control abnormalities in PTSD is not well-understood, including the neural mechanisms that subserve these functions. In this K23 application, the P.I. proposes a multi-method approach that includes behavioral data collection, fMRI and Diffusion Tensor Imaging (DTI) to investigate cognitive control processes in individuals with and without PTSD. She proposes the use a novel attentional control task, the Affective Number Stroop, during fMRI to examine PTSD-specific patterns of task performance and neural response; this task requires the viewer to perform a challenging cognitive task while ignoring evocative, often trauma-relevant pictures. The first aim of her study is to examine group-wise differences in response time and task accuracy as participants are presented with trauma-related, positive, and neutral distractors. The second aim is to investigate corresponding patterns of functional connectivity as participants engage in this task. Finally, diffusion tensor Imaging (DTI) will be used to investigate PTSD-specific abnormalities in white matter connections that may contribute to functional differences; this represents the third aim. These three sets of data may reveal distinct patterns of cognitive control dysfunction that are unique to individuals with PTSD; between-group differences in behavioral and fMRI data during task performance will be examined, as well as differences in white matter structure that support the existence of these phenomena. The successful identification of cognitive control abnormalities and their neural mechanisms in PTSD has the power to inform current theoretical models of this disorder, as well as novel, tailored interventions that target these problems. This project draws on the P.I.'s strengths in th fields of neuropsychology, PTSD research, and neuroimaging methods, and expands her training over the course of four years to include an improved knowledge of affective neuroscience paradigms, as well as functional and structural connectivity methods. During this time, as she rises from a junior faculty position to tenured Assistant Professor, the P.I. will obtain the requisite knowledge and skills that will enhance her ability to produce methodologically-sound, and clinically-relevant, research on the neuropsychology of PTSD.