title: Direct and indirect parieto-medial temporal pathways for spatial navigation in humans: evidence from resting-state functional connectivity.
abstract: Anatomical and functional findings in primates suggest the existence of a dedicated parieto-medial temporal pathway for spatial navigation, consisting of both direct and indirect projections from the caudal inferior parietal lobe (cIPL) to the hippocampus and the parahippocampal cortex, with indirect projections relaying through the posterior cingulate and retrosplenial cortex. This neural network is largely unexplored in humans. This study aimed at testing the existence of a parieto-medial temporal pathway for spatial navigation in humans. We explored the cortical connectivity patterns of the parahippocampal place area (PPA), the retrosplenial cortex (RSC), and the hippocampus (HC) using resting-state functional connectivity MRI. Our results demonstrate the existence of connections between the medial temporal lobe structures, i.e., PPA and HC, and the angular gyrus (AG), the human homologue of cIPL, as well as between RSC and AG. These connectivity patterns seem to reflect the direct and the indirect projections found in primates from cIPL to the medial temporal lobe. Such a result deserves feasible considerations to better understand the brain networks underpinning human spatial navigation.
authors.affiliation: Department of Psychology, "Sapienza" University of Rome, Via dei Marsi, 78, 00185, Rome, Italy. maddalena.boccia@uniroma1.it.|Cognitive and Motor Rehabilitation Unit, IRCCS Fondazione Santa Lucia of Rome, Rome, Italy. maddalena.boccia@uniroma1.it.
authors.forename: Maddalena
authors.initials: M
authors.lastname: Boccia
authors.affiliation: Department of Psychology, "Sapienza" University of Rome, Via dei Marsi, 78, 00185, Rome, Italy.|Cognitive and Motor Rehabilitation Unit, IRCCS Fondazione Santa Lucia of Rome, Rome, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Sulpizio
authors.affiliation: Klingberg Laboratory, Neuroscience Department, Karolinska Institute, Stockholm, Sweden.
authors.forename: Federico
authors.initials: F
authors.lastname: Nemmi
authors.affiliation: Department of Psychology, "Sapienza" University of Rome, Via dei Marsi, 78, 00185, Rome, Italy.|Cognitive and Motor Rehabilitation Unit, IRCCS Fondazione Santa Lucia of Rome, Rome, Italy.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Guariglia
authors.affiliation: Department of Psychology, "Sapienza" University of Rome, Via dei Marsi, 78, 00185, Rome, Italy.|Cognitive and Motor Rehabilitation Unit, IRCCS Fondazione Santa Lucia of Rome, Rome, Italy.
authors.forename: Gaspare
authors.initials: G
authors.lastname: Galati
mesh_terms: D000328:Adult; D001931:Brain Mapping; D005260:Female; D006624:Hippocampus / Q000033:anatomy & histology / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009434:Neural Pathways / Q000033:anatomy & histology / Q000502:physiology; D020534:Parahippocampal Gyrus / Q000033:anatomy & histology* / Q000502:physiology*; D010296:Parietal Lobe / Q000033:anatomy & histology* / Q000502:physiology*; D065854:Spatial Navigation / Q000502:physiology*; D013702:Temporal Lobe / Q000033:anatomy & histology* / Q000502:physiology*; D055815:Young Adult
keywords: Hippocampus; Parahippocampal place area; Resting state; Retrosplenial cortex; Spatial navigation; fMRI