title: Neonatal hypoxia, hippocampal atrophy, and memory impairment: evidence of a causal sequence.
abstract: Neonates treated for acute respiratory failure experience episodes of hypoxia. The hippocampus, a structure essential for memory, is particularly vulnerable to such insults. Hence, some neonates undergoing treatment for acute respiratory failure might sustain bilateral hippocampal pathology early in life and memory problems later in childhood. We investigated this possibility in a cohort of 40 children who had been treated neonatally for acute respiratory failure but were free of overt neurological impairment. The cohort had mean hippocampal volumes (HVs) significantly below normal control values, memory scores significantly below the standard population means, and memory quotients significantly below those predicted by their full scale IQs. Brain white matter volume also fell below the volume of the controls, but brain gray matter volumes and scores on nonmnemonic neuropsychological tests were within the normal range. Stepwise linear regression models revealed that the cohort's HVs were predictive of degree of memory impairment, and gestational age at treatment was predictive of HVs: the younger the age, the greater the atrophy. We conclude that many neonates treated for acute respiratory failure sustain significant hippocampal atrophy as a result of the associated hypoxia and, consequently, show deficient memory later in life.
authors.affiliation: Developmental Cognitive Neuroscience Unit Murdoch Childrens Research Institute, Melbourne, Victoria 3052, Australia.
authors.forename: Janine M
authors.initials: JM
authors.lastname: Cooper
authors.affiliation: Imaging and Biophysics Unit.
authors.forename: David G
authors.initials: DG
authors.lastname: Gadian
authors.affiliation: Developmental Cognitive Neuroscience Unit Freie Universität, Berlin 14195, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Jentschke
authors.affiliation: Cardiac Unit, UCL Institute of Child Health, London WC1N 1EH, UK Cardiac Intensive Care.
authors.forename: Allan
authors.initials: A
authors.lastname: Goldman
authors.affiliation: Developmental Cognitive Neuroscience Unit University of Castilla-La Mancha, Albacete 02006, Spain.
authors.forename: Monica
authors.initials: M
authors.lastname: Munoz
authors.affiliation: Developmental Cognitive Neuroscience Unit.
authors.forename: Georgia
authors.initials: G
authors.lastname: Pitts
authors.affiliation: Imaging and Biophysics Unit Department of Radiology.
authors.forename: Tina
authors.initials: T
authors.lastname: Banks
authors.affiliation: Imaging and Biophysics Unit Department of Radiology.
authors.forename: W Kling
authors.initials: WK
authors.lastname: Chong
authors.affiliation: Cardiac Unit, UCL Institute of Child Health, London WC1N 1EH, UK Cardiac Intensive Care.
authors.forename: Aparna
authors.initials: A
authors.lastname: Hoskote
authors.affiliation: UCL Institute of Cardiovascular Science, London WC1E 6BT, UK.
authors.forename: John
authors.initials: J
authors.lastname: Deanfield
authors.affiliation: Developmental Cognitive Neuroscience Unit.
authors.forename: Torsten
authors.initials: T
authors.lastname: Baldeweg
authors.affiliation: Developmental Cognitive Neuroscience Unit.
authors.forename: Michelle
authors.initials: M
authors.lastname: de Haan
authors.affiliation: Laboratory of Neuropsychology, National Institute of Mental Health, Bethesda, MD 20892, USA.
authors.forename: Mortimer
authors.initials: M
authors.lastname: Mishkin
authors.affiliation: Developmental Cognitive Neuroscience Unit Department of Neuropsychology, Great Ormond Street Hospital, London WC1N 3JH, UK.
authors.forename: Faraneh
authors.initials: F
authors.lastname: Vargha-Khadem
mesh_terms: D000293:Adolescent; D001284:Atrophy / Q000209:etiology; D057189:Checklist; D002648:Child; D015331:Cohort Studies; D003710:Demography; D005260:Female; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007361:Intelligence Tests; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders / Q000209:etiology*; D009483:Neuropsychological Tests; D066250:Pretectal Region; D012128:Respiratory Distress Syndrome / Q000150:complications* / Q000473:pathology*; D013223:Statistics as Topic; D014706:Verbal Learning
keywords: developmental amnesia; hippocampal volumes; hypoxia