High-fidelity mapping of repetition-related changes in the parietal memory network

• Published in: NeuroImage (Orlando, Fla.) Vol. 199; pp. 427 - 439
• Main Authors: Gilmore, Adrian W., Nelson, Steven M., Laumann, Timothy O., Gordon, Evan M., Berg, Jeffrey J., Greene, Deanna J., Gratton, Caterina, Nguyen, Annie L., Ortega, Mario, Hoyt, Catherine R., Coalson, Rebecca S., Schlaggar, Bradley L., Petersen, Steven E., Dosenbach, Nico U.F., McDermott, Kathleen B.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.10.2019; Elsevier Limited
• Subjects: Adult; Brain Mapping - methods; Datasets; Experiments; Facial Recognition - physiology; Familiarity; Female; fMRI; Functional magnetic resonance imaging; Highly-sampled human subjects; Humans; Information processing; Magnetic Resonance Imaging; Male; Memory; Mental Recall - physiology; Nerve Net - diagnostic imaging; Nerve Net - physiology; Neurosciences; Parietal cortex; Parietal Lobe - diagnostic imaging; Parietal Lobe - physiology; Pattern Recognition, Visual - physiology; Recognition, Psychology - physiology; Repetition; Retrieval; Scholarships & fellowships; Young Adult; Retrieval; fMRI; Highly-sampled human subjects; Familiarity; Memory; Parietal cortex
• ISSN: 1053-8119; 1095-9572; 1095-9572
• DOI: 10.1016/j.neuroimage.2019.06.011

fMRI studies of human memory have identified a “parietal memory network” (PMN) that displays distinct responses to novel and familiar stimuli, typically deactivating during initial encoding but robustly activating during retrieval. The small size of PMN regions, combined with their proximity to the neighboring default mode network, makes a targeted assessment of their responses in highly sampled subjects important for understanding information processing within the network. Here, we describe an experiment in which participants made semantic decisions about repeatedly-presented stimuli, assessing PMN BOLD responses as items transitioned from experimentally novel to repeated. Data are from the highly-sampled subjects in the Midnight Scan Club dataset, enabling a characterization of BOLD responses at both the group and single-subject level. Across all analyses, PMN regions deactivated in response to novel stimuli and displayed changes in BOLD activity across presentations, but did not significantly activate to repeated items. Results support only a portion of initially hypothesized effects, in particular suggesting that novelty-related deactivations may be less susceptible to attentional/task manipulations than are repetition-related activations within the network. This in turn suggests that novelty and familiarity may be processed as separable entities within the PMN.