Species Differences in the Organization of the Ventral Cochlear Nucleus

Baizer, Joan S.; Wong, Keit Men; Salvi, Richard; Manohar, Senthilvelan; Sherwood, Chet C.; Hof, Patrick R.; Baker, James F.; Witelson, Sandra F.

doi:10.1002/ar.23751

Cited by 5 publications

(7 citation statements)

References 158 publications

(209 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…There are no clear additions, deletions, or specializations of these nuclei apparent, as seen, for example, in the African elephant (Maseko et al, 2013). The architecture and location of the cochlear and superior olivary nuclear complexes, the inferior colliculus, plus their internal nuclear subdivisions and the topological relationships of these subdivisions, all appear to follow the pattern observed across mammals (e.g., Baizer et al, 2014, 2018; Paxinos et al, 2009). This brainstem auditory blueprint extends to the fibers, pathways, and associated nuclei of the trapezoid body and lateral lemniscus, as well as to the neurochemistry of the individual nuclei in these regions (e.g., de León, Coveñas, Narváez, Aguirre, & González‐Barón, 1993; Imam, Bhagwandin, Ajao, Spocter, & Manger, 2019).…”

Section: Discussionmentioning

confidence: 70%

The brain of the African wild dog. III. The auditory system

Chengetanai

Bhagwandin

Bertelsen

et al. 2020

J of Comparative Neurology

Self Cite

View full text Add to dashboard Cite

The large external pinnae and extensive vocal repertoire of the African wild dog (Lycaon pictus) has led to the assumption that the auditory system of this unique canid may be specialized. Here, using cytoarchitecture, myeloarchitecture, and a range of immunohistochemical stains, we describe the systems‐level anatomy of the auditory system of the African wild dog. We observed the cochlear nuclear complex, superior olivary nuclear complex, lateral lemniscus, inferior colliculus, medial geniculate body, and auditory cortex all being in their expected locations, and exhibiting the standard subdivisions of this system. While located in the ectosylvian gyri, the auditory cortex includes several areas, resembling the parcellation observed in cats and ferrets, although not all of the auditory areas known from these species could be identified in the African wild dog. These observations suggest that, broadly speaking, the systems‐level anatomy of the auditory system, and by extension the processing of auditory information, within the brain of the African wild dog closely resembles that observed in other carnivores. Our findings indicate that it is likely that the extraction of the semantic content of the vocalizations of African wild dogs, and the behaviors generated, occurs beyond the classically defined auditory system, in limbic or association neocortical regions involved in cognitive functions. Thus, to obtain a deeper understanding of how auditory stimuli are processed, and how communication is achieved, in the African wild dog compared to other canids, cortical regions beyond the primary sensory areas will need to be examined in detail.

show abstract

Section: Discussionmentioning

confidence: 70%

The brain of the African wild dog. III. The auditory system

Chengetanai

Bhagwandin

Bertelsen

et al. 2020

J of Comparative Neurology

Self Cite

View full text Add to dashboard Cite

show abstract

“…This not only enhances their contrast thus allowing for a more accurate segmentation but also causes a neuroinflammatory state and cell damage (Zucca et al, 2017) which could explain the more pronounced age-related volume loss in these nuclei. Age-related structural and functional alterations have also been described for the VTA (Siddiqi et al, 1999) NTS (Sturrock, 1992;Yamamoto et al, 2005;Hardy et al, 2018) and for the OI (Pesce et al, 1980;Sjöbeck et al, 1999;Lasn et al, 2006;Baizer et al, 2018) although the findings are less consistent than those for SN and NR. There exist to the best of our knowledge no studies investigating age effects in CR or RPO but functions in which these nuclei, play important roles i.e., locomotion, pain perception and sleep, are affected by age (Bassant and Poindessous-Jazat, 2002;Farrell, 2012;Lau et al, 2015) which supports the notion of age-related volume losses in these structures.…”

Section: Discussionmentioning

confidence: 95%

Mapping internal brainstem structures using T1 and T2 weighted 3T images

Mueller

2023

Front. Neuroimaging

View full text Add to dashboard Cite

BackgroundMany neurodegenerative diseases affect the brainstem and often do so in an early stage. The overall goal of this project was (a) to develop a method to segment internal brainstem structures from T1 and T2 weighted sequences by taking advantage of the superior myelin contrast of the T1/T2 ratio image (RATIO) and (b) to test if this approach provides biological meaningful information by investigating the effects of aging on different brainstem gray matter structures.Methods675 T1 and T2 weighted images were obtained from the Human Connectome Project Aging. The intensities of the T1 and T2 images were re-scaled and RATIO images calculated. The brainstem was isolated and k-means clustering used to identify five intensity clusters. Non-linear diffeomorphic mapping was used to warp the five intensity clusters in subject space into a common space to generate probabilistic group averages/priors that were used to inform the final probabilistic segmentations at the single subject level. The five clusters corresponded to five brainstem tissue types (two gray matters, two mixed gray/white, and 1 csf/tissue partial volume).ResultsThese cluster maps were used to calculate Jacobian determinant maps and the mean Jacobians of 48 brainstem gray matter structures extracted. Significant linear or quadratic age effects were found for all but five structures.ConclusionsThese findings suggest that it is possible to obtain a biologically meaningful segmentation of internal brainstem structures from T1 and T2 weighted sequences using a fully automated segmentation procedure.

show abstract

“…Figures 2 , 3 , 6 , and 8 show photomicrographs of sections that were prepared for several different projects on the human brainstem. Details of the methods are given in earlier publications ( Baizer and Broussard, 2010 ; Baizer et al, 2011a , b , 2014 , 2018a , b , 2021 ).…”

Section: What Do We Know About the Brain In Asd: Candidate Structures And Their Connectionsmentioning

confidence: 99%

“…Those studies suggest that a similar cellular analysis of the other main brainstem auditory nuclei that interconnect with the SOC (cochlear nuclei, inferior colliculus) might also reveal abnormalities. We have studied the neurochemical organization of the dorsal and ventral cochlear nuclei in humans ( Baizer et al, 2014 , 2018a ); these brain sections are available for comparison with sections from ASD brains. Figures 8A,B shows the dorsal and ventral cochlear nuclei in humans.…”

Section: What Do We Know About the Brain In Asd: Candidate Structures And Their Connectionsmentioning

confidence: 99%

Functional and Neuropathological Evidence for a Role of the Brainstem in Autism

Baizer

2021

Front. Integr. Neurosci.

Self Cite

View full text Add to dashboard Cite

The brainstem includes many nuclei and fiber tracts that mediate a wide range of functions. Data from two parallel approaches to the study of autistic spectrum disorder (ASD) implicate many brainstem structures. The first approach is to identify the functions affected in ASD and then trace the neural systems mediating those functions. While not included as core symptoms, three areas of function are frequently impaired in ASD: (1) Motor control both of the limbs and body and the control of eye movements; (2) Sensory information processing in vestibular and auditory systems; (3) Control of affect. There are critical brainstem nuclei mediating each of those functions. There are many nuclei critical for eye movement control including the superior colliculus. Vestibular information is first processed in the four nuclei of the vestibular nuclear complex. Auditory information is relayed to the dorsal and ventral cochlear nuclei and subsequently processed in multiple other brainstem nuclei. Critical structures in affect regulation are the brainstem sources of serotonin and norepinephrine, the raphe nuclei and the locus ceruleus. The second approach is the analysis of abnormalities from direct study of ASD brains. The structure most commonly identified as abnormal in neuropathological studies is the cerebellum. It is classically a major component of the motor system, critical for coordination. It has also been implicated in cognitive and language functions, among the core symptoms of ASD. This structure works very closely with the cerebral cortex; the cortex and the cerebellum show parallel enlargement over evolution. The cerebellum receives input from cortex via relays in the pontine nuclei. In addition, climbing fiber input to cerebellum comes from the inferior olive of the medulla. Mossy fiber input comes from the arcuate nucleus of the medulla as well as the pontine nuclei. The cerebellum projects to several brainstem nuclei including the vestibular nuclear complex and the red nucleus. There are thus multiple brainstem nuclei distributed at all levels of the brainstem, medulla, pons, and midbrain, that participate in functions affected in ASD. There is direct evidence that the cerebellum may be abnormal in ASD. The evidence strongly indicates that analysis of these structures could add to our understanding of the neural basis of ASD.

show abstract

Species Differences in the Organization of the Ventral Cochlear Nucleus

Cited by 5 publications

References 158 publications

The brain of the African wild dog. III. The auditory system

The brain of the African wild dog. III. The auditory system

Mapping internal brainstem structures using T1 and T2 weighted 3T images

Functional and Neuropathological Evidence for a Role of the Brainstem in Autism

Contact Info

Product

Resources

About