title: MRI uncovers disrupted hippocampal microstructure that underlies memory impairments after early-life adversity.
abstract: Memory and related cognitive functions are progressively impaired in a subgroup of individuals experiencing childhood adversity and stress. However, it is not possible to identify vulnerable individuals early, a crucial step for intervention. In this study, high-resolution magnetic resonance imaging (MRI) and intra-hippocampal diffusion tensor imaging (DTI) were employed to examine for structural signatures of cognitive adolescent vulnerabilities in a rodent model of early-life adversity. These methods were complemented by neuroanatomical and functional assessments of hippocampal network integrity during adolescence, adulthood and middle-age. The high-resolution MRI identified selective loss of dorsal hippocampal volume, and intra-hippocampal DTI uncovered disruption of dendritic structure, consistent with disrupted local connectivity, already during late adolescence in adversity-experiencing rats. Memory deteriorated over time, and stunting of hippocampal dendritic trees was apparent on neuroanatomical analyses. Thus, disrupted hippocampal neuronal structure and connectivity, associated with cognitive impairments, are detectable via non-invasive imaging modalities in rats experiencing early-life adversity. These high-resolution imaging approaches may constitute promising tools for prediction and assessment of at-risk individuals in the clinic. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Anatomy and Neurobiology.
authors.forename: Jenny
authors.initials: J
authors.lastname: Molet
authors.affiliation: Department of Pediatrics, UC-Irvine, Irvine, CA, 92697-4475, USA.
authors.forename: Pamela M
authors.initials: PM
authors.lastname: Maras
authors.affiliation: Department of Pediatrics, UC-Irvine, Irvine, CA, 92697-4475, USA.|Department of Pediatrics, Loma Linda University School of Medicine, Loma Linda, CA, 92350, USA.
authors.forename: Eli
authors.initials: E
authors.lastname: Kinney-Lang
authors.affiliation: Department of Neurosurgery, UCLA, Los Angeles, CA, 90095-6901, USA.
authors.forename: Neil G
authors.initials: NG
authors.lastname: Harris
authors.affiliation: Department of Pediatrics, Loma Linda University School of Medicine, Loma Linda, CA, 92350, USA.
authors.forename: Faisal
authors.initials: F
authors.lastname: Rashid
authors.affiliation: Department of Anatomy and Neurobiology.
authors.forename: Autumn S
authors.initials: AS
authors.lastname: Ivy
authors.affiliation: Department of Anatomy and Neurobiology.|Department of Neurology, UC-Irvine, Irvine, CA, 92697-4475, USA.
authors.forename: Ana
authors.initials: A
authors.lastname: Solodkin
authors.affiliation: Department of Pediatrics, Loma Linda University School of Medicine, Loma Linda, CA, 92350, USA.
authors.forename: Andre
authors.initials: A
authors.lastname: Obenaus
authors.affiliation: Department of Anatomy and Neurobiology.|Department of Pediatrics, UC-Irvine, Irvine, CA, 92697-4475, USA.|Department of Neurology, UC-Irvine, Irvine, CA, 92697-4475, USA.
authors.forename: Tallie Z
authors.initials: TZ
authors.lastname: Baram
mesh_terms: D000818:Animals; D015331:Cohort Studies; D003345:Corticosterone / Q000097:blood; D003441:Crowding; D056324:Diffusion Tensor Imaging; D004777:Environment; D005260:Female; D006624:Hippocampus / Q000000981:diagnostic imaging* / Q000254:growth & development / Q000473:pathology; D006799:Housing, Animal; D008027:Light; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders / Q000097:blood / Q000000981:diagnostic imaging* / Q000209:etiology* / Q000473:pathology; D023421:Models, Animal; D009622:Noise; D009929:Organ Size; D017966:Pyramidal Cells / Q000473:pathology; D011863:Radioimmunoassay; D011897:Random Allocation; D017207:Rats, Sprague-Dawley; D013315:Stress, Psychological / Q000097:blood / Q000150:complications* / Q000000981:diagnostic imaging* / Q000473:pathology
chemical_list: D003345:Corticosterone
keywords: brain networks; cognitive vulnerabilities; diffusion tensor imaging (DTI); early-life stress; magnetic resonance imaging (MRI)