ArticleCerebral cortex (New York, N.Y. : 1991)2020
Invariant Synapse Density and Neuronal Connectivity Scaling in Primate Neocortical Evolution.
Article in Cerebral cortex (New York, N.Y. : 1991), 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 38 papers.
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Who cites it
38 citing papers in PubMed, 61 citations in OpenAlex.
- Age-related changes in synapse ultrastructure and neuroprotective effect of dietary curcumin in the lateral prefrontal cortex layer 3 of the rhesus monkey.GeroScience · 2026Article
- Human-specific SRGAP2 paralogs synchronize neotenic microglial maturation and synaptic development.Neuron · 2026Article
- A Role for Astrocyte Metabolism in Species-Specific Neuronal Development.bioRxiv : the preprint server for biology · 2026Article
- Metabolism Controls the Timing of Human Brain Development and Maturation.Journal of inherited metabolic disease · 2026Review
- Primate gut microbiota induce evolutionarily salient changes in mouse neurodevelopment.Proceedings of the National Academy of Sciences of the United States of America · 2026Article
- Human CLOCK enhances neocortical function.Nature neuroscience · 2025Article
- Distribution of Serotonergic Transporter Innervation in the Nucleus Accumbens and Ventral Pallidum Is Highly Conserved Among Primates.The Journal of comparative neurology · 2025Article
- If you please, draw me a neuron - linking evolutionary tinkering with human neuron evolution.Current opinion in genetics & development · 2024Review
- Adult neurogenesis and "immature" neurons in mammals: an evolutionary trade-off in plasticity?Brain structure & function · 2024Review
- Shell Constraints on Evolutionary Body Size-Limb Size Allometry Can Explain Morphological Conservatism in the Turtle Body Plan.Ecology and evolution · 2024Article
- Evolutionary scaling and cognitive correlates of primate frontal cortex microstructure.Brain structure & function · 2024Article
- Multi-scale spiking network model of human cerebral cortex.Cerebral cortex (New York, N.Y. : 1991) · 2024Article
- Reconciliation of weak pairwise spike-train correlations and highly coherent local field potentials across space.Cerebral cortex (New York, N.Y. : 1991) · 2024Article
- Invariance of Mitochondria and Synapses in the Primary Visual Cortex of Mammals Provides Insight Into Energetics and Function.The Journal of comparative neurology · 2024Article
- The uniqueness of human vulnerability to brain aging in great ape evolution.Science advances · 2024Article
- Human-specific paralogs of SRGAP2 induce neotenic features of microglia structural and functional maturation.bioRxiv : the preprint server for biology · 2024Article
- Article
- Variation and convergence in the morpho-functional properties of the mammalian neocortex.Frontiers in systems neuroscience · 2024Review
- Episodic memory assessment: effects of sex and age on performance and response time during a continuous recognition task.Frontiers in human neuroscience · 2024Article
- Article
Corrections and comments
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Authors and funding
9 authors at 7 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Synapses are involved in the communication of information from one neuron to another. However, a systematic analysis of synapse density in the neocortex from a diversity of species is lacking, limiting what can be understood about the evolution of this fundamental aspect of brain structure. To address this, we quantified synapse density in supragranular layers II-III and infragranular layers V-VI from primary visual cortex and inferior temporal cortex in a sample of 25 species of primates, including humans. We found that synapse densities were relatively constant across these levels of the cortical visual processing hierarchy and did not significantly differ with brain mass, varying by only 1.9-fold across species. We also found that neuron densities decreased in relation to brain enlargement. Consequently, these data show that the number of synapses per neuron significantly rises as a function of brain expansion in these neocortical areas of primates. Humans displayed the highest number of synapses per neuron, but these values were generally within expectations based on brain size. The metabolic and biophysical constraints that regulate uniformity of synapse density, therefore, likely underlie a key principle of neuronal connectivity scaling in primate neocortical evolution.
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