Background: Alzheimer neuropathology (AD) is found in almost half of patients with non-semantic primary progressive aphasia (PPA). This study examined hippocampal abnormalities in PPA to determine similarities to those described in amnestic AD.
Methods: In 37 PPA patients and 32 healthy controls, we generated hippocampal subfield surface maps from structural MRIs and administered a face memory test. We analyzed group and hemisphere differences for surface shape measures and their relationship with test scores and ApoE genotype.
Results: The hippocampus in PPA showed inward deformity (CA1 and subiculum subfields) and outward deformity (CA2-4+DG subfield) and smaller left than right volumes. Memory performance was related to hippocampal shape abnormalities in PPA patients, but not controls, even in the absence of memory impairments.
Conclusions: Hippocampal deformity in PPA is related to memory test scores. This may reflect a combination of intrinsic degenerative phenomena with transsynaptic or Wallerian effects of neocortical neuronal loss.
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http://dx.doi.org/10.1016/j.dadm.2014.11.013 | DOI Listing |
PLoS One
January 2025
National Centre for Neuroimmunology and Emerging Diseases, Griffith University, Australia.
Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) patients share similar symptoms including post-exertional malaise, neurocognitive impairment, and memory loss. The neurocognitive impairment in both conditions might be linked to alterations in the hippocampal subfields. Therefore, this study compared alterations in hippocampal subfields of 17 long COVID, 29 ME/CFS patients, and 15 healthy controls (HC).
View Article and Find Full Text PDFEnviron Res
January 2025
Département de Psychologie, Université du Québec à Montréal, C.P. 8888 succursale Centre-ville, Montréal, Québec, H3C 3P8, Canada; Centre de Recherche du CHU Sainte-Justine, 3175, Chemin de La Côte-Sainte-Catherine, Montréal, Québec, H3T 1C5, Canada. Electronic address:
Exposure to lead, mercury, and polychlorinated biphenyls (PCBs) has been causally linked to spatial memory deficits and hippocampal changes in animal models. The Inuit community in Northern Canada is exposed to higher concentrations of these contaminants compared to the general population. This study aimed to 1) investigate associations between prenatal and current contaminant exposures and medial temporal brain volumes in Inuit late adolescents; 2) examine the relationship between these brain structures and spatial memory; and 3) assess the mediating role of brain structures in the association between contaminant exposure and spatial memory.
View Article and Find Full Text PDFBiol Psychiatry Cogn Neurosci Neuroimaging
January 2025
Department of Neurosurgery, The First Medical Centre of Chinese PLA General Hospital, Beijing, China; Neurosurgery Institute, Chinese PLA General Hospital, Beijing, PR China. Electronic address:
Background: Chronic cortisol overexposure plays a significant role in the development of neuropathological changes associated with neuropsychiatric and neurodegenerative disorders. The hippocampus, the primary target of cortisol, may exhibit characteristic regional responses due to its internal heterogeneity. This study explores structural and functional alterations of hippocampal subfields in Cushing's disease (CD), an endogenous model of chronic cortisol overexposure.
View Article and Find Full Text PDFNeurol Sci
January 2025
Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China.
Background And Objective: Numerous studies suggest that the development of Alzheimer's Disease (AD) leads to a reduction in overall hippocampal volume. However, there is limited research exploring whether pre-morbid differences in hippocampal volume impact the risk of AD. This study aims to delve into the causal relationship between hippocampal subregional volume and AD using bidirectional Mendelian Randomization (MR) methods.
View Article and Find Full Text PDFAlzheimers Res Ther
January 2025
Normandie Univ, UNICAEN, INSERM, U1237, PhIND "Physiopathology and Imaging of Neurological Disorders", NeuroPresage Team, Institut Blood and Brain @ Caen-Normandie, GIP Cyceron, Bd Henri Becquerel, BP 5229, Caen, 14074, France.
Background: Subclinical depressive symptoms increase the risk of developing Alzheimer's disease (AD). The neurobiological mechanisms underlying this link may involve stress system dysfunction, notably related to the hippocampus which is particularly sensitive to AD. We aimed to investigate the links between blood stress markers and changes in brain regions involved in the stress response in older adults with or without subclinical depressive symptoms.
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