Cognitive Psychology Commons^™

The Relationship Between P300 Evoked Potentials And Prefrontal Cortex Oxygen Use: A Combined Eeg And Nirs Study, Will S. Rizer

All NMU Master's Theses

The P300 subcomponent, P3b, is an event related potential detected at the scalp surface when a working memory comparison results in differences between the contents of working memory and incoming stimulus information. Previous research has indicated that as infrequent targets become more difficult to detect (morphologically similar to a frequent non-target stimulus) the P300 becomes attenuated. fMRI research has also indicated increased prefrontal cortex (PFC) activity during P300 generation. To examine the relationship between P3b amplitude and PFC activity participants performed an easy and difficult target detection task in both EEG and NIRS called the oddball. The EEG and behavioral …

Perceiving Oldness In Parietal Cortex: Fmri Characterization Of A Parietal Memory Network, Adrian Gilmore

Arts & Sciences Electronic Theses and Dissertations

The manner in which the human brain recognizes certain stimuli as novel or familiar is a matter of ongoing investigation. The overarching goal of this dissertation is to improve our understanding of how this may be accomplished. More specifically, work contained herein focuses on a recently described "parietal memory network" (PMN; Gilmore et al., 2015) that shows opposite patterns of activity when perceiving novel or familiar stimuli: deactivating in response to novelty, and activating in response to familiarity. Critically, our understanding of this network is based on explicit memory tasks, in which subjects are deliberately instructed to learn or remember …

The Neural And Cognitive Basis Of Cumulative Lifetime Familiarity Assessment, Devin Duke

Electronic Thesis and Dissertation Repository

Perirhinal cortex (PrC) has been implicated as a brain region in the medial temporal lobes (MTL) that critically contributes to familiarity-based recognition memory, a process that allows for recognition to occur independently of contextual recollection. Informed by neurophysiological research in non-human primates, fMRI, as well as behavioural work in humans, the current thesis research tests the novel hypothesis that PrC cortex functioning also underlies the ability to assess cumulative lifetime familiarity with object concepts that are characterized by a lifetime of experiences. In Chapter 2, a patient (NB) with a left anterior temporal lobe (ATL) lesion that included PrC as …

Acute Stress Exposure And Expression Of Instrumentally Conditioned Financial Preferences: An Fmri Study, William Travis Mccuddy

Master's Theses (2009 -)

Recent research suggests acute stress exposure is associated with increased habit-based over goal-oriented decision making (e.g., Schwabe & Wolf, 2011). The current study examined whether acute stress promotes the expression of simple financial preferences “overtrained” to the point of habit in the face of a changing environment where said preferences were later rendered non-optimal. Over three days participants (N = 28) learned to discriminate between visual stimuli probabilistically associated with monetary gains or losses and made decisions between stimuli with real financial outcomes. On the fourth day after exposure to either an acute stressor or control procedure participants performed the …

The Semantic Memory Imaging In Late Life Pilot Study, Michael Adam Sugarman

Wayne State University Dissertations

Introduction: Several functional magnetic resonance imaging (fMRI) studies have analyzed the famous name discrimination task (FNDT), an uncontrolled semantic memory probe requiring discrimination between famous and unfamiliar individuals. Completion of this simple task recruits a semantic memory network that has shown utility in determining risk for Alzheimer's disease (AD). Specific semantic memory probes using biographical information associated with famous individuals may build on previous findings and yield superior information regarding risk for AD.

Method: Sixteen cognitively intact elders completed the FNDT and two novel tasks during fMRI: Categories (matching famous individuals to occupational categories) and Attributes (matching famous individuals to …

A Brain System For Auditory Working Memory, Sukhbinder Kumar, Sabine Joseph, Phillip E. Gander, Nicolas Barascud, Andrea R. Halpern, Timothy D. Griffiths

Faculty Journal Articles

The brain basis for auditory working memory, the process of actively maintaining sounds in memory over short periods of time, is controversial. Using functional magnetic resonance imaging in human participants, we demonstrate that the maintenance of single tones in memory is associated with activation in auditory cortex. In addition, sustained activation was observed in hippocampus and inferior frontal gyrus. Multivoxel pattern analysis showed that patterns of activity in auditory cortex and left inferior frontal gyrus distinguished the tone that was maintained in memory. Functional connectivity during maintenance was demonstrated between auditory cortex and both the hippocampus and inferior frontal cortex. …