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Patzke, N.

Publications and source records attributed to Patzke, N..

4 recordsLinked to original sources

A comparative framework for neocortical sulcal anatomy in pinnipeds

The transition of pinnipeds from terrestrial ancestors into marine environments provides a unique opportunity to examine how cortical organisation has changed with adaptation to life in water. Here, we examined neocortical sulcal anatomy in nine species representing all three extant pinniped families using cortical surfaces reconstructed from post-mortem MRI. Building on a standardised framework previously established for land-dwelling (fissiped) carnivorans, we developed identification criteria for major pinniped sulci and compared their configurations with those observed across fissipeds. Major sulci were broadly conserved, but pinnipeds exhibited characteristic modifications, including a complex, highly branched pseudosylvian configuration and distinct frontoparietal sulcal patterns, with further family-level variation in both territories. This observed variation in sulcal patterns may reflect pronounced differences in locomotor, tactile, and vocal specialisations, generating hypotheses about how cortical organisation may vary with adaptation to marine environments. Together, these findings establish a common anatomical framework across Carnivora for investigating how cortical organisation diversified in relation to behaviour and ecology.

neuroscience↗

Comparative neuroimaging of the carnivoran brain: Neocortical sulcal anatomy

Carnivorans are an important study object for comparative neuroscience, as they exhibit a wide range of behaviours, ecological adaptations, and social structures. Previous studies have mainly examined relative brain size, but a comprehensive understanding of brain diversity requires the investigation of other aspects of their neuroanatomy. Here, we obtained primarily post-mortem brain scans from twenty-six species of the order Carnivora, spanning across eight families with diverse representatives and including additional individuals for selected species, to create the largest Carnivoran brain collection to date. We then reconstructed their cortical surfaces, and examined neocortical sulcal anatomy to establish a framework for systematic inter-species comparisons. We observed distinct regional variations in sulcal anatomy, potentially related to the species behaviour and ecology. Arctoidea species with pronounced forepaw dexterity exhibited complex sulcal configurations in the presumed somatosensory cortex but low sulcal complexity in the presumed visual and auditory occipitotemporal cortex. Canidae had the largest number of unique major sulci with a unique sulcus in the occipital cortex and highly social canids featuring an additional frontal cortex sulcus. We also observed differentially complex occipito-temporal sulcal patterns in Felidae and Canidae, indicative of changes in auditory and visual areas that may be related to foraging strategies and social behaviour. In conclusion, this study presents an inventory of the sulcal anatomy of a number of rarely studied carnivoran brains including detailed digital atlases and establishes a framework and novel avenues for further investigations employing a variety of neuroimaging modalities to reveal more about carnivoran brain diversity.

neuroscience↗

Impaired Epigenesis of Imprinting Predispositions Causes Autism-like Behavioral Phenotypes in Domestic Chicks

Several environmental chemicals are suspected as risk factors for autism spectrum disorder (ASD), including valproic acid (VPA) and pesticides acting on nicotinic acetylcholine receptor (nAChR) if exposed during pregnancy. However, their target processes in fetal neuro-development are unspecified. We report that fetal injection of VPA impaired the imprinting of an artifact object in hatchlings, while the predisposed preference to biological motion (BM) remained intact. Blockade of nAChR acted oppositely, namely, spared imprinting and impaired BM in chicks. Beside ketamine and tubocurarine, significant effects of imidacloprid (a neonicotinoid insecticide) appeared at dose [≤]1ppm. Despite the distinct processes, both VPA and nAChR blockade similarly impaired imprinting of biological image composed of point-light animation. Furthermore, both impairments were rescued by post-natal bumetanide treatment, suggesting common pathology underlying the social attachment malformation. Ambient neonicotinoid could hinder adaptive socialization through impaired development of visual perception in early neonates.

animal behavior and cognition↗

Amplification of potential thermogenetic mechanisms in cetacean brains

To elucidate causality underlying the evolution of large brains in cetaceans, we examined the brains of 16 cetartiodactyl species for evidence of non-shivering thermogenesis. In comparison to the artiodactyl brain, the cetacean brain exhibits an expanded expression of uncoupling protein 1 (UCP1, UCPs being mitochondrial inner membrane proteins that dissipate the proton gradient to generate heat) in cortical neurons, localization of UCP4 within a substantial proportion of glia throughout the brain, and an increased density of noradrenergic axonal boutons (noradrenaline functioning to control concentrations of and activate UCPs). Thus, cetacean brains possess multiple characteristics indicative of intensified thermogenetic functionality that can be related to their current and historical obligatory aquatic niche. These findings necessitate reassessment of our concepts regarding the reasons for large brain evolution and associated functional capacities in cetaceans.

neuroscience↗