BACKGROUND: Previous studies have suggested a relationship between neuroanatomical and neurofunctional hippocampal alterations and episodic memory impairments in multiple sclerosis (MS) patients. OBJECTIVE: We examined hippocampus volume and functional connectivity (FC) changes in MS patients with different episodic memory capabilities. METHODS: Hippocampal subfield volume and FC changes were compared in two subgroups of MS patients with and without episodic memory impairment (multiple sclerosis impaired (MSi) and multiple sclerosis preserved (MSp), respectively) and healthy controls (HC). A discriminant function (DF) analysis was used to identify which of these neuroanatomical and neurofunctional parameters were the most relevant components of the mnemonic profiles of HC, MSp, and MSi. RESULTS: MSi showed reduced volume in several hippocampal subfields compared to MSp and HC. Ordinal gradation (MSi > MSp > HC) was also observed for FC between the posterior hippocampus and several cortical areas. DF-based analyses revealed that reduced right fimbria volume and enhanced FC at the right posterior hippocampus were the main neural signatures of the episodic memory impairments observed in the MSi group. CONCLUSION: Before any sign of episodic memory alterations (MSp), FC increased on several pathways that connect the hippocampus with cortical areas. These changes further increased when the several hippocampal volumes reduced and memory deficits appeared (MSi).
BACKGROUND: Previous studies have suggested a relationship between neuroanatomical and neurofunctional hippocampal alterations and episodic memory impairments in multiple sclerosis (MS) patients. OBJECTIVE: We examined hippocampus volume and functional connectivity (FC) changes in MS patients with different episodic memory capabilities. METHODS: Hippocampal subfield volume and FC changes were compared in two subgroups of MS patients with and without episodic memory impairment (multiple sclerosis impaired (MSi) and multiple sclerosis preserved (MSp), respectively) and healthy controls (HC). A discriminant function (DF) analysis was used to identify which of these neuroanatomical and neurofunctional parameters were the most relevant components of the mnemonic profiles of HC, MSp, and MSi. RESULTS: MSi showed reduced volume in several hippocampal subfields compared to MSp and HC. Ordinal gradation (MSi > MSp > HC) was also observed for FC between the posterior hippocampus and several cortical areas. DF-based analyses revealed that reduced right fimbria volume and enhanced FC at the right posterior hippocampus were the main neural signatures of the episodic memory impairments observed in the MSi group. CONCLUSION: Before any sign of episodic memory alterations (MSp), FC increased on several pathways that connect the hippocampus with cortical areas. These changes further increased when the several hippocampal volumes reduced and memory deficits appeared (MSi).
Authors: Yolanda Aladro; Laudino López-Alvarez; Jorge Mario Sánchez-Reyes; Juan Antonio Hernández-Tamames; Helena Melero; Sandra Rubio-Fernández; Israel Thuissard; Marta Cerezo-García Journal: J Neurol Date: 2018-07-11 Impact factor: 4.849
Authors: Lisa Glukhovsky; Rachel Brandstadter; Victoria M Leavitt; Stephen Krieger; Korhan Buyukturkoglu; Michelle Fabian; Ilana Katz Sand; Sylvia Klineova; Claire S Riley; Fred D Lublin; Aaron E Miller; James F Sumowski Journal: Mult Scler Date: 2020-06-22 Impact factor: 5.855
Authors: Peter Bede; Eoin Finegan; Rangariroyashe H Chipika; Stacey Li Hi Shing; Jeffrey Lambe; James Meaney; Janice Redmond Journal: Front Neurol Date: 2018-08-23 Impact factor: 4.003
Authors: Marlene Tahedl; Seth M Levine; Mark W Greenlee; Robert Weissert; Jens V Schwarzbach Journal: Front Neurol Date: 2018-10-11 Impact factor: 4.003
Authors: Philipp G Sämann; Juan Eugenio Iglesias; Boris Gutman; Dominik Grotegerd; Ramona Leenings; Claas Flint; Udo Dannlowski; Emily K Clarke-Rubright; Rajendra A Morey; Theo G M van Erp; Christopher D Whelan; Laura K M Han; Laura S van Velzen; Bo Cao; Jean C Augustinack; Paul M Thompson; Neda Jahanshad; Lianne Schmaal Journal: Hum Brain Mapp Date: 2020-12-27 Impact factor: 5.038