Journal of Comparative Neurology最新文献

{"title":"Distribution of Serotonergic Transporter Innervation in the Nucleus Accumbens and Ventral Pallidum Is Highly Conserved Among Primates","authors":"Heather N. Smith,&nbsp;Danielle N. Jones,&nbsp;Emily L. Munger,&nbsp;Patrick R. Hof,&nbsp;Chet C. Sherwood,&nbsp;Mary Ann Raghanti","doi":"10.1002/cne.70083","DOIUrl":"https://doi.org/10.1002/cne.70083","url":null,"abstract":"<p>The nucleus accumbens (NAcc) and ventral pallidum (VP) are key nodes in the mesolimbic reward pathway that facilitate stimulus salience, including the regulation of social motivation and attachment. Primate species display variation in social behaviors, including different levels of impulsivity, bonding, and aggression. Previous research has implicated neuromodulation of the reward pathway in the differential expression of various social behaviors, suggesting that differences in neurotransmitter innervation may play a role in species-specific patterns. To explore this, we examined serotonergic innervation in the NAcc and VP among primates. We used stereology to quantify serotonin transporter-immunoreactive (SERT-ir) axon length density in the NAcc and VP of 13 primate species, including humans, great apes, and cercopithecid and platyrrhine monkeys. Our data show that serotonergic innervation density within both the NAcc and VP is highly conserved among species. This finding contrasts with our previous findings of higher levels of SERT-ir axons in the dorsal striatum of humans and great apes relative to monkeys, a human-specific increase in dopaminergic innervation within the NAcc and VP, and a human-specific increase of neuropeptide Y in the NAcc, highlighting the mosaic nature of innervation patterns among species.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 8","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.70083","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144894208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Ventral Tectal Longitudinal Column: A Midbrain Nucleus for Modulation of Auditory Processing in the Cochlear Nucleus, Superior Olivary Complex, and Inferior Colliculus","authors":"Brett R. Schofield,&nbsp;William A. Noftz,&nbsp;Yoani N. Herrera,&nbsp;Michael T. Roberts","doi":"10.1002/cne.70080","DOIUrl":"https://doi.org/10.1002/cne.70080","url":null,"abstract":"<p>A ventral tectal longitudinal column (TLCv) has been described in rats and is hypothesized to provide multisensory modulation of acoustic processing in the superior olivary complex. The TLCv is a column of cells in the dorsomedial tectum extending rostro-caudally through the inferior and superior colliculi. It receives ascending auditory input and projects to the superior olivary complex. Further insight into TLCv function has been hampered by limited information on its connections. Here, we provide evidence that a TLCv is recognizable in mice and that it has more extensive connections than previously believed. Deposit of retrograde tracer into the superior olivary complex labels cells bilaterally in the TLCv, comparable to results seen in rats. Viral labeling of neuronal projections demonstrates input to the TLCv from the superior olivary complex and from the inferior colliculus. Thus, the TLCv in mice has inputs and outputs similar to those described in rats. Additional experiments with retrograde tracers revealed more extensive outputs from the TLCv. Neurons in the TLCv are labeled after the deposition of retrograde tracers into the cochlear nucleus or into the inferior colliculus. The projections from the TLCv to these targets, like those to the superior olivary complex, are bilateral. These projections are much broader than those described previously. The results suggest that the TLCv could exert modulation over a wide expanse of the auditory brainstem, from the cochlear nucleus through the inferior colliculus.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 8","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.70080","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144894403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sources of Synaptic Input to Neurons in the Nucleus Accumbens Shell That Project to the Ventral Pallidum","authors":"Shuanghong Li,&nbsp;Sa Li,&nbsp;Gilbert J. Kirouac","doi":"10.1002/cne.70081","DOIUrl":"https://doi.org/10.1002/cne.70081","url":null,"abstract":"<p>The shell of the nucleus accumbens (NAcSh) regulates motivation and reward via its dense projection to the ventral pallidum (VP). This ventral striatopallidal system has also been shown to regulate the activity of midbrain dopamine neurons and the release of dopamine in the NAcSh. The present study applied monosynaptic rabies tracing in the rat to quantify the brain-wide sources of synaptic input to neurons in the medial NAcSh that project to the ventromedial VP. The ventral subiculum of the hippocampus (vSub) was the largest source of input cells to the NAcSh-VP projection neurons. Anterograde tracing of vSub-NAcSh projection neurons demonstrated that their fibers terminated densely in the NAcSh largely avoiding other regions of the striatum. Another relatively strong source of input cells included the anterior part of the paraventricular nucleus of the thalamus (aPVT). The CA1, lateral septal nucleus, VP, paratenial thalamic nucleus, bed nucleus of the stria terminalis, lateral preoptic area and dorsomedial nucleus of the hypothalamus were moderately strong sources of input neurons. The prefrontal cortex, amygdala, and the basolateral nucleus of the amygdala were found to be relatively weak sources of input. A lack of sex differences for all the sources of input identified indicates that there is no apparent sexual dimorphism in the afferents to the striatopallidal system. In summary, the vSub and the aPVT are the major sources of cortical and thalamic monosynaptic inputs to the NAcSh-VP projection neurons where these inputs converge to regulate behavior and dopamine release in the NAcSh.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 8","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.70081","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144881438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dopaminergic Neurons in the Zebrafish Subpallium Belong to the Extended Medial Amygdala","authors":"Daniel Armbruster,&nbsp;Thomas Mueller,&nbsp;Wolfgang Driever","doi":"10.1002/cne.70079","DOIUrl":"https://doi.org/10.1002/cne.70079","url":null,"abstract":"<p>The amygdala is a heterogeneous, multinuclear telencephalic structure critical for motivated and emotion-related behaviors in vertebrates. In ray-finned fish (Actinopterygii) like the teleost zebrafish, a telencephalic outward-growing process called eversion makes defining amygdaloid territories particularly challenging. Teleosts are also peculiar in that they develop numerous dopaminergic (DA) neurons in the subpallium, while in tetrapods, such populations are less prominent or appear only transiently. To shed light on the organization of the amygdala in teleosts, we pursued an evolutionary developmental approach focusing on the topological origin of subpallial DA neurons. Specifically, we analyzed the distribution of tyrosine hydroxylase (Th) in conjunction with expression patterns of <i>pax6a+b</i>, <i>isl1a</i>, <i>nkx2.1</i>, <i>lhx8a</i>, <i>otpa+b</i>, and <i>calb2a</i> as markers of different telencephalic subdivisions in brains of 5- and 30-day-old zebrafish (<i>Danio rerio</i>, Teleostei). Our data show that the previously identified dorsalmost division of the ventral telencephalon (Vdd) needs to be subdivided into an anteroventral <i>pax6a/b</i>-positive portion (Vdd1) and a posterodorsal <i>pax6a/b</i>-negative portion (Vdd2). This <i>pax6a</i>-negative Vdd2 portion develops into the extended medial amygdala (EMeA), including the DA population adjacent to the pallial–subpallial border. Our results also show that the EMeA DA neurons form a heterogeneous group of amygdaloid neurons because they differentially express <i>calb2a</i> and <i>sst7</i>. Our work sheds light on the early evolution and development of the amygdala and provides a foundation for functional analysis of the newly defined DA subtypes of the extended amygdala in zebrafish.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 8","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.70079","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144782212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial Distribution and Morphology of CaMKII-Expressing Amacrine Cells in Marmoset, Macaque, and Human Retina","authors":"Alyssa K. Baldicano,&nbsp;Paul R. Martin,&nbsp;Ulrike Grünert","doi":"10.1002/cne.70078","DOIUrl":"https://doi.org/10.1002/cne.70078","url":null,"abstract":"<p>Over 30 types of amacrine cells have been described in the primate retina, yet few are well characterized. Here, we investigated amacrine cells expressing the alpha subunit of calcium/calmodulin-dependent protein kinase II (CaMKII) in the retinas of human, macaque (<i>Macaca fascicularis, Macaca nemestrina</i>), and marmoset (<i>Callithrix jacchus</i>) monkeys using immunohistochemistry and intracellular injections, with a focus on displaced amacrine cells (dACs) in the ganglion cell layer. The spatial density of CaMKII-positive dACs decreases with the distance from the fovea, but in the peripheral temporal retina, the density of CaMKII-positive dACs nevertheless exceeds the density of retinal ganglion cells. In all species, CaMKII-positive dACs include cells expressing choline acetyltransferase (ChAT) cells, but in the human retina, only 60% of the ON ChAT population is CaMKII-positive. Conversely, in the marmoset and the macaque, about 80% of ON ChAT cells co-express CaMKII, but only 55% of ON ChAT cells in humans do so. Intracellular injections of CaMKII-positive dACs with the lipophilic dye DiI revealed ON starburst and semilunar Type 3 cells in all three species, but in the human retina, at least three additional types were detected. In the inner nuclear layer, CaMKII is expressed by multiple populations of amacrine cells, which are distinguished based on their soma size and staining intensity, but OFF ChAT cells do not co-express CaMKII. We conclude that ON- and OFF-ChAT cells show distinct patterns of CaMKII expression and that the diversity of CaMKII-expressing dACs in humans is greater than that in marmoset or macaque retina.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 7","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.70078","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144688110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Role of the Amygdala in Nonbreeding Aggression in Male Green Anole Lizards, Anolis carolinensis","authors":"Niveditha Sankar,&nbsp;Brooke R. Andel,&nbsp;Bernadette L. Igo,&nbsp;Anna R. Wilcox,&nbsp;Rachel E. Cohen","doi":"10.1002/cne.70077","DOIUrl":"https://doi.org/10.1002/cne.70077","url":null,"abstract":"<div>\u0000 \u0000 <p>Aggression is a set of hostile behaviors expressed to defend and/or obtain resources. Although a social behavior network (SBN) has been postulated to explain the neural mechanisms underlying aggression, the extent of behavioral modulation by specific brain regions remains unclear. Additionally, the regulation of the SBN during the nonbreeding season (NBS) in seasonal breeders that express territorial aggression is still unknown. Thus, we aimed to study the role of one node of the SBN, the amygdala, in green anole lizards as this species displays dynamic changes in aggression, reduced testosterone levels, and increased number of neurons in the amygdala during the NBS compared to the breeding season. Male lizards were placed in a stereotactic apparatus and injected with either a neurotoxin (staurosporine) to damage the amygdala or saline as a control. These focal male lizards were also exposed to size-matched conspecifics before and 3 days after surgery to quantify aggressive behaviors. We found that partly damaging the amygdala significantly reduced aggression levels but did not affect their latency to initiate aggressive behaviors, providing support for the idea that the amygdala mediates aggression but not motivation in this species. Additionally, there was no relationship between aggression and plasma testosterone levels, suggesting that the nonbreeding aggression we measured was independent of plasma testosterone levels. These results indicate that the amygdala might play a significant role in the SBN to regulate NBS aggression and is not dependent on plasma testosterone levels.</p>\u0000 </div>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 7","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144688219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Regional Ultrastructural Analysis of the Cellular and Synaptic Architecture of the Mouse Vestibular Periphery, With Reference to the Chinchilla","authors":"Maha Ahmad,&nbsp;Rege Vlahodimos,&nbsp;Manal Hameed,&nbsp;Fahad Imran,&nbsp;Tony Madappallil,&nbsp;Jayasree Oruganti,&nbsp;Behrooz S. Shamsaddin,&nbsp;Anna Lysakowski","doi":"10.1002/cne.70074","DOIUrl":"https://doi.org/10.1002/cne.70074","url":null,"abstract":"<p>The mouse utricular macula is increasingly being used as a model preparation to study the vestibular periphery because we can generate transgenic mice to investigate molecular details of development and function. Yet, detailed knowledge of its synaptic innervation is lacking or inconsistent. Accurate ribbon synapse numbers and location are needed to quantitatively model quantal transmission in the mouse, as has recently been done for non-quantal transmission in the Type I vestibular HC (Govindaraju et al. 2023). We investigated this at the ultrastructural level, as we have done previously in the chinchilla and squirrel monkey. The same investigative methods that we used in those previous studies (dissector and transmission electron microscopy [TEM]) were used to confirm recent confocal and TEM studies of the synaptic ribbons contained in the two types of vestibular HCs, Type I (enveloped by a large calyceal, or chalice-shaped, terminal) and Type II (contacted by more conventional synaptic boutons). Because vestibular function varies depending on specific regions in the sensory epithelium (central/striolar, peripheral/extrastriolar), the present study examined the different regions and found both regional and cell-type variations. Synaptic ribbon numbers were higher in Type II than in Type I HCs in both the utricular macula and the crista ampullaris. Previous work in chinchilla crista ampullaris had a gradient of synaptic ribbons in Type I HCs, being more numerous in the central zone versus the periphery. In the mouse crista (present study), the opposite was true; ribbon numbers were slightly higher in the periphery. For comparison to the mouse utricle, we also collected new data from the chinchilla utricular macula in this study. Finally, a variety of ribbon shapes were present in the vestibular epithelium, ranging from spheroid to elongated and intermediate forms. The reasons for these observed variations in shapes are unknown. These data should inform future functional and modeling studies of the vestibular sensory epithelium.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 7","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.70074","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144688095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Persistent Disruptions in Prefrontal Connectivity Despite Behavioral Rescue by Environmental Enrichment in a Mouse Model of Rett Syndrome","authors":"Sofie Ährlund-Richter,&nbsp;Jonathan Harpe,&nbsp;Giselle Fernandes,&nbsp;Ruby Lam,&nbsp;Mriganka Sur","doi":"10.1002/cne.70073","DOIUrl":"https://doi.org/10.1002/cne.70073","url":null,"abstract":"<p>Rett syndrome, a neurodevelopmental disorder caused by loss-of-function mutations in the <i>MECP2</i> gene, is characterized by severe motor, cognitive, and emotional impairments. Some of the deficits may result from changes in cortical connections, especially downstream projections of the prefrontal cortex (PFC), which may also be targets of restoration following rearing conditions such as environmental enrichment that alleviate specific symptoms. Here, using a heterozygous <i>Mecp2^+/−</i> female mouse model closely analogous to human Rett syndrome, we investigated the impact of early environmental enrichment on behavioral deficits and PFC connectivity. Behavioral analyses revealed that enriched housing rescued fine motor deficits and reduced anxiety, with enrichment-housed <i>Mecp2^+/−</i> mice performing comparably to wild-type (WT) controls in rotarod and open field assays. Anatomical mapping of top-down anterior cingulate cortex (ACA) projections demonstrated altered PFC connectivity in <i>Mecp2^+/−</i> mice, with increased axonal density in the somatosensory cortex and decreased density in the motor cortex compared to WT controls. ACA axons revealed shifts in hemispheric distribution, particularly in the medial network regions, with <i>Mecp2^+/−</i> mice exhibiting reduced ipsilateral dominance. These changes were unaffected by enriched housing, suggesting that structural abnormalities in PFC connectivity persist despite behavioral improvements. Enriched housing rescued brain-derived neurotrophic factor (BDNF) levels in the hippocampus but failed to restore BDNF levels in the PFC, consistent with the persistent deficits observed in prefrontal axonal projections. These findings highlight the focal nature of changes induced by reduction of MeCP2 and by exposure to environmental enrichment and suggest that environmental enrichment starting in adolescence can alleviate behavioral deficits in <i>Mecp2^+/−</i> mice without reversing abnormalities in large-scale cortical connectivity.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 7","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.70073","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144647286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Serotonin Receptors in Areas of the Emotion Regulation Network in Human and Rat Brains—A Comparative Autoradiographic Study","authors":"Anika Kuckertz,&nbsp;Ling Zhao,&nbsp;Olga Kedo,&nbsp;Katrin Amunts,&nbsp;Nicola PalomeroGallagher","doi":"10.1002/cne.70068","DOIUrl":"https://doi.org/10.1002/cne.70068","url":null,"abstract":"<p>Serotonergic neurotransmission is crucial for emotion processing and is dysregulated in mood disorders. To analyze the pathophysiology of disease and develop effective pharmacological treatments, the suitability of the rat as a model for translational research must be continuously validated. In vitro receptor autoradiography was used to characterize (dis)similarities of regional and laminar serotonergic 5-HT_1A and 5-HT₂ receptor distributions between components of the human emotion regulation network and homologous rat areas, including areas of the lateral prefrontal, orbitofrontal anterior and midcingulate cortices, hippocampal cornu Ammonis (CA) and dentate gyrus (DG), and the accumbens, central amygdaloid, and mediodorsal thalamic nuclei. In both species, mean 5-HT_1A densities were highest in cingulate area 25/infralimbic cortex and the hippocampus, and lowest in the accumbens. Whereas human CA presented significantly higher 5-HT_1A density than DG, the opposite was found in rats. Across the cortical depth, in humans, layers I–III and V contained the highest and lowest 5-HT_1A densities, respectively. In rats, layers I–II contained the lowest and layers V–VI the highest 5-HT_1A values. Mean 5-HT₂ densities were lower than 5-HT_1A densities in all areas of both species, whereby layers III and VI contained the highest and lowest 5-HT₂ densities, respectively. Rats presented a more widespread range of significant differences concerning the ratio between 5-HT_1A and 5-HT₂ receptors across examined areas than did humans. Concluding, this comparative study reveals species differences in 5-HT_1A and 5-HT₂ receptor densities in components of the emotion regulation network, which should be considered when using the rat as a model in the translational research of mood disorders.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 7","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.70068","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144646843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Brain of the African Wild Dog. VI. The Motor System","authors":"Samson Chengetanai,&nbsp;Adhil Bhagwandin,&nbsp;Mads F. Bertelsen,&nbsp;Therese Hård,&nbsp;Patrick R. Hof,&nbsp;Muhammad A. Spocter,&nbsp;Paul R. Manger","doi":"10.1002/cne.70072","DOIUrl":"https://doi.org/10.1002/cne.70072","url":null,"abstract":"<p>Social behaviors in the African wild dog involve a range of complex movements, including biting, pushing, embracing, mounting, face and muzzle licking, paw placement, play fighting, and wrestling. In this study, we employ a range of architectural and immunohistochemical stains to provide a qualitative description of the motor system in the brain of one representative individual of the African wild dog. The appearance of the motor system in the African wild dog does not differ substantively to that reported in other carnivores and is neurochemically like that of the domestic dog; however, one significant difference was detected: the presence of a distinct fascicle of protoplasmic commissural dendrites at the rostral pole of the hypoglossal nucleus. The chemoarchitecture and complement of motor cortical areas and dorsal thalamus, striatopallidal complex and associated nuclei, cerebellum, red nucleus, descending motor pathways, inferior olivary nuclear complex, cranial nerve motor nuclei, and ventral horn of the cervical spinal cord of the African wild dog do not reveal qualitative differences to that observed in the domestic dog. At the rostral pole of the hypoglossal nucleus, protoplasmic commissural dendrites form a distinct fascicle, this fascicle being a feature that has not been reported in other mammals. The presence of this feature indicates complex neural control of the tongue and may facilitate vocalization control through the potential combination of lateralized aspects of vocalizations in a nucleus playing a major role in the production of vocalizations.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 7","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.70072","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144635371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}