ArticleBrain structure & function2015
In contrast to many other mammals, cetaceans have relatively small hippocampi that appear to lack adult neurogenesis.
Article in Brain structure & function, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 84 papers.
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84 citing papers in PubMed, 174 citations in OpenAlex.
- Phylogeny of Cortical-Hippocampal Projections Reveals Selective Elimination of Input From Sensory Regions.Hippocampus · 2026Article
- Immature Neurons in the Postnatal Brain: Markers, Modulation, and Involvement in Normal and Aberrant Plasticity.International journal of molecular sciences · 2026Review
- Review
- Cellular Composition of the Brain of a Northern Minke Whale.The Journal of comparative neurology · 2025Article
- Reduced Adult Neurogenesis in Humans Results From a Tradeoff Rather Than Direct Negative Selection.BioEssays : news and reviews in molecular, cellular and developmental biology · 2025Review
- Multispecies characterization of immature neurons in the mammalian amygdala reveals their expansion in primates.PLoS biology · 2025Article
- "Of Marine Mammal Neuroscience and Men": Needs and Perspectives in Marine Mammal Neuroscience.The Journal of comparative neurology · 2025Review
- Atg5 in microglia regulates sex-specific effects on postnatal neurogenesis in Alzheimer's disease.npj aging · 2025Article
- Adult neurogenesis and "immature" neurons in mammals: an evolutionary trade-off in plasticity?Brain structure & function · 2024Review
- Anatomical and volumetric description of the guiana dolphin (Sotalia guianensis) brain from an ultra-high-field magnetic resonance imaging.Brain structure & function · 2024Article
- 5-Bromo-2'-deoxyuridine labeling: historical perspectives, factors influencing the detection, toxicity, and its implications in the neurogenesis.Neural regeneration research · 2024Review
- Adult neurogenesis: a real hope or a delusion?Neural regeneration research · 2024Review
- The amygdaloid body of the family Delphinidae: a morphological study of its central nucleus through calbindin-D28k.Frontiers in neuroanatomy · 2024Article
- Which neurodevelopmental processes continue in humans after birth?Frontiers in neuroscience · 2024Article
- Modelling adult neurogenesis in the aging rodent hippocampus: a midlife crisis.Frontiers in neuroscience · 2024Article
- Adult human neurogenesis: A view from two schools of thought.IBRO neuroscience reports · 2023Review
- Prolonged fixation and post-mortem delay impede the study of adult neurogenesis in mice.Communications biology · 2023Article
- Review
- Methods to study adult hippocampal neurogenesis in humans and across the phylogeny.Hippocampus · 2023Review
- Localization and Characterization of Major Neurogenic Niches in the Brain of the Lesser-Spotted DogfishInternational journal of molecular sciences · 2023Article
24 more citing papers are in PubMed but not listed here.
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Authors and funding
16 authors at 10 institutions in 7 countries.
Funding
Abstract
The hippocampus is essential for the formation and retrieval of memories and is a crucial neural structure sub-serving complex cognition. Adult hippocampal neurogenesis, the birth, migration and integration of new neurons, is thought to contribute to hippocampal circuit plasticity to augment function. We evaluated hippocampal volume in relation to brain volume in 375 mammal species and examined 71 mammal species for the presence of adult hippocampal neurogenesis using immunohistochemistry for doublecortin, an endogenous marker of immature neurons that can be used as a proxy marker for the presence of adult neurogenesis. We identified that the hippocampus in cetaceans (whales, dolphins and porpoises) is both absolutely and relatively small for their overall brain size, and found that the mammalian hippocampus scaled as an exponential function in relation to brain volume. In contrast, the amygdala was found to scale as a linear function of brain volume, but again, the relative size of the amygdala in cetaceans was small. The cetacean hippocampus lacks staining for doublecortin in the dentate gyrus and thus shows no clear signs of adult hippocampal neurogenesis. This lack of evidence of adult hippocampal neurogenesis, along with the small hippocampus, questions current assumptions regarding cognitive abilities associated with hippocampal function in the cetaceans. These anatomical features of the cetacean hippocampus may be related to the lack of postnatal sleep, causing a postnatal cessation of hippocampal neurogenesis.
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