Institut des Sciences de l'Evolution (ISEM UMR 5554), Université Montpellier 2, , CC 064, Place Eugène Bataillon, 34270 Montpellier Cedex 05, France, Muséum national d'Histoire naturelle, UMR 7207 CR2P CNRS/MNHN/UPMC, , 8 rue Buffon, CP 38, 75231 Paris Cedex 05, France, Museum of Paleontology, The University of Michigan, , Ann Arbor, MI 48109-1079, USA, O.D. Earth & History of life, Royal Belgian Institute of Natural History, , 29 rue Vautier, 1000 Brussels, Belgium.
Published: April 2014
AI Article Synopsis
Article Abstract
Expansion of the brain is a key feature of primate evolution. The fossil record, although incomplete, allows a partial reconstruction of changes in primate brain size and morphology through time. Palaeogene plesiadapoids, closest relatives of Euprimates (or crown-group primates), are crucial for understanding early evolution of the primate brain. However, brain morphology of this group remains poorly documented, and major questions remain regarding the initial phase of euprimate brain evolution. Micro-CT investigation of the endocranial morphology of Plesiadapis tricuspidens from the Late Palaeocene of Europe--the most complete plesiadapoid cranium known--shows that plesiadapoids retained a very small and simple brain. Plesiadapis has midbrain exposure, and minimal encephalization and neocorticalization, making it comparable with that of stem rodents and lagomorphs. However, Plesiadapis shares a domed neocortex and downwardly shifted olfactory-bulb axis with Euprimates. If accepted phylogenetic relationships are correct, then this implies that the euprimate brain underwent drastic reorganization during the Palaeocene, and some changes in brain structure preceded brain size increase and neocortex expansion during evolution of the primate brain.
Low-frequency non-syndromic hearing loss (LFNSHL) is a rare auditory disorder affecting frequencies ≤ 2000 Hz. To elucidate its genetic basis, we conducted whole-exome sequencing on nine Chinese families (31 affected individuals) with LFNSHL. Four heterozygous pathogenic variants, including two novel variants, were identified in common LFNSHL-related genes (WFS1, DIAPH1) and less common genes (TNC, EYA4), achieving a 44% genetic diagnosis rate.
Learning new categories is fundamental to cognition, occurring in daily life through various sensory modalities. However, it is not well known how acquiring new categories can modulate the brain networks. Resting-state functional connectivity is an effective method for detecting short-term brain alterations induced by various modality-based learning experiences.
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Intracortical microstimulation (ICMS) is a method for restoring sensation to people with paralysis as part of a bidirectional brain-computer interface (BCI) to restore upper limb function. Evoking tactile sensations of the hand through ICMS requires precise targeting of implanted electrodes. Here we describe the presurgical imaging procedures used to generate functional maps of the hand area of the somatosensory cortex and subsequent planning that guided the implantation of intracortical microelectrode arrays.
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