The sensory homunculus; how somatosensory cortex proportionally represents the sensory epithelium of the body surface.
Context in source publication
... as shown in figure 3 we see how CHAPTER ONE the representation of the retinal activity (including that in foveal and extra-foveal areas) is system- atically re-represented at the level of primary visual cortex. Similarly for the somatosensory system, as shown in figure 4, the body surface (more specifically activity from the sensory epithelium of the skin) is re-represented in somatosensory cortex. A more familiar represen- tation of the sensory homunculus is illustrated in figure 5 (Penfield 1958). ...
One of the important tasks of a humanoid-robot auditory system is speaker localization. It is used for the construction of the surrounding acoustic scene and as an input for additional processing methods. Localization is usually required to operate indoors under high reverberation levels. Recently, an algorithm for speaker localization under these...
The somatosensory homunculus shows a deformed human figure that illustrates the proportion of the brain devoted to the sense of touch in each part of the body. Originally based on Penfield’s brain mapping, it has been presented as a drawing of a human figure along the somatosensory cortex, an independent human figure, and a sculpted figure. Until recently, these homunculi have been male due to the lack of information on the female somatosensory cortex. A few female homunculi have been drawn. Based on more current brain research, the authors present, to our knowledge, the first sculpted 3D female somatosensory homunculus.
The term "auditory neuropathy" is being used in a rapidly increasing number of papers in the audiology/otolaryngology literature for a variety of individuals (mostly children) who fulfill the following criteria: (1) understanding of speech worse than predicted from the degree of hearing loss on their behavioral audiograms; (2) recordable otoacoustic emissions and/or cochlear microphonic; together with (3) absent or atypical auditory brain stem responses. Because of the general lack of anatomic foundation for the label "auditory neuropathy" as currently used, we review the anatomy of the auditory pathway, the definition of neuropathy and its demyelinating, axonal, and mixed variants. We submit that the diagnostic term "auditory neuropathy" is anatomically inappropriate unless patients have documented evidence for selective involvement of either the spiral ganglion cells or their axons, or of the 8th nerve as a whole. In view of biologic differences between peripheral nerves and white matter tracts in the brain, the term "auditory neuropathy" is inappropriate for pathologies affecting the central auditory pathway in the brainstem and brain selectively. Published reports of patients with "auditory neuropathy" indicate that they are extremely heterogeneous in underlying medical diagnosis, age, severity, test results, and that only a small number have undergone the detailed investigations that would enable a more precise diagnosis of the locus of their pathologies. The electrophysiology of peripheral neuropathies and the deficits expected with pathologies affecting the hair cells, spiral ganglion cells and their axons (auditory neuropathy sensu stricto), and brain stem relays are reviewed. In order to serve patients adequately, including potential candidates for cochlear implants, and to increase knowledge of auditory pathologies, we make a plea for more comprehensive evaluation of patients who fulfill the currently used audiologic criteria for "auditory neuropathy" in an effort to pinpoint the site of their pathologies. We suggest that the term auditory neuropathy be limited to cases in which the locus of pathology is limited to the spiral ganglion cells, their processes, or the 8th nerve, and that the term neural hearing loss be considered for pathologies that affect all higher levels of the auditory pathway, from the brainstem to the auditory cortex.