PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 10994424

The cochlear nuclei revisited.

W B Dublin
View original source ↗Export metadata ↓

Abstract

The cochlear nuclei (CN) in man consist of the dorsal (DCN), superior ventral (SVCN), and inferior ventral (IVCN). The CN is located on the dorsolateral surface of the brain stem at the junction of the medulla with the pons. The DCN curves over the inferior cerebellar peduncle and forms part of its dorsolateral surface. The IVCN is found beneath the lateral portion of the DCN. The SVCN is for the most part covered by the inferior portion of the middle cerebellar peduncle. Of five types of nerve cells found in the CN in man, spheroid cells appear especially in the SVCN. They are the second-order neurons of the main ascending neural auditory pathway. Their injury forms the basis for hearing loss of central type. The SVCN can be mapped into estimated frequency strata progressing from low frequencies ventral to high frequencies dorsal. Spheroid cells are susceptible to injury notably by anoxia and especially centering around an estimated 4,000 Hz frequency level in the SVCN. The pattern of injury of spheroid cells can be displayed in comparison with audiometric tracing on a standard audiogram chart.

Explore related subjects

Brain MappingCochlear NucleusHearing Loss, CentralHumansNeuronsPitch PerceptionJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

W B Dublin. The cochlear nuclei revisited.. https://doi.org/10.1177/019459988209000613

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2008

Corpus callosal connection mapping using cortical gray matter parcellation and DT-MRI.

Population maps of the corpus callosum (CC) and cortical lobe connections were generated by combining cortical gray matter parcellation with the diffusion tensor fiber tractography of individual subjects. This method is based on the fact that the cortical lobes of both hemispheres are interconnected by the corpus callosal fibers. T1-weighted structural MRIs and diffusion tensor MRIs (DT-MRI) of 22 right-handed, healthy subjects were used. Forty-seven cortical parcellations in the dorsal prefrontal cortex, ventral prefrontal cortex, sensory-motor cortex, parietal cortex, temporal cortex, and occipital cortex were semi-automatically derived from structural MRIs, registered to DT-MRI, and used to identify callosal fibers. The probabilistic connections to each cortex were mapped on entire mid-sagittal CC voxels that had anatomical homology between subjects as determined by spatial registration. According to the population maps of the callosal connections, the ventral prefrontal cortex and parts of the dorsal prefrontal cortex both project fibers through the genu and rostrum. The CC regions through which the superior frontal cortex passes extend into the posterior body. Fibers arising from the parietal lobe and occipital lobe run mainly through the splenium, while fibers arising from the sensory-motor cortex pass through the isthmus. In general, dorsal or medial cortical lobes project fibers through the dorsal region of the CC, while lateral cortical lobes project fibers through the ventral region of the CC. The probabilistic subdivision of the CC by connecting cortical gray matter provides a more precise understanding of the CC.

Brain Mapping↗
PubMed2007

Observer-independent analysis of high-resolution MR images of the human cerebral cortex: in vivo delineation of cortical areas.

Using high-resolution MRI, it is now possible to examine the living human cortex down to a resolution of less than 300 mum. Thus, in vivo imaging is now approaching the resolution that has been successfully used in histological analysis of the cerebral cortex for many years, e.g., low-magnification light microscopy. This allows unprecedented views of cortical microstructure that reflect defined histological features, specifically, individual cortical layers. As in histological brain mapping, it is possible to use the changes in the cortical lamination patterns to define individual cortical areas. This allows in vivo neuroanatomical maps to be generated for individual subjects and precise correlation of the results from functional imaging studies in these subjects with their own microanatomical information. To this end, we adapted the well-established observer-independent cytoarchitectonic mapping techniques for defining cortical borders based on changes in cortical lamination for in vivo parcellation of high-resolution structural MR images.

Brain Mapping↗
PubMed2007

Functional brain imaging: a window into the visuo-vestibular systems.

PURPOSE OF REVIEW: Advances have been made in identifying how areas involved in processing vestibular, ocular motor, and visual information are represented in the human cortex as well as the cortical interaction between these systems in healthy subjects. RECENT FINDINGS: While we know how some vestibular and ocular motor disorders modify visuo-vestibular interaction by changing the 'normal' cortical activation-deactivation patterns, it is still early days in functional magnetic resonance imaging studies of patients with specific disorders. Findings from current brain imaging studies of several vestibular, ocular motor, and cerebellar disorders are presented. SUMMARY: The promise of more insights into the complex neuronal networks of the human cortex is great.

Brain Mapping↗