. Cunningham's Text-book of anatomy. Anatomy. THE ACOUSTIC AREA AND FIBEE-TEACTS. In the embryo of the fifth month (Fig. 583, B), as well as in every later stage, even up to the adult condition (Fig. 582), an area upon the superior surface of the temporal operculum can be seen to slope medially towards the upper limb of the sulcus circularis, behind the insula. This area constitutes the receptive centre for acoustic impressions—the gyrus temporalis transversus or Heschl's convolution —although the extent of this acoustico-sensory area does not coincide exactly with that of the transverse tempo
. Cunningham's Text-book of anatomy. Anatomy. THE ACOUSTIC AREA AND FIBEE-TEACTS. In the embryo of the fifth month (Fig. 583, B), as well as in every later stage, even up to the adult condition (Fig. 582), an area upon the superior surface of the temporal operculum can be seen to slope medially towards the upper limb of the sulcus circularis, behind the insula. This area constitutes the receptive centre for acoustic impressions—the gyrus temporalis transversus or Heschl's convolution —although the extent of this acoustico-sensory area does not coincide exactly with that of the transverse temporal gyrus. The area formed by the upper surface of the temporal operculum immediately behind this prominent transverse gyrus is also called by the same name, so that there are anterior and posterior transverse temporal gyri (Fig. 582; the posterior transverse temporal gyrus is not labelled in the figure). In studying the brain-stem we have seen that a tract of fibres originating in the cochlear terminal nuclei (in the medulla oblongata) crosses the median plane (corpus trapezoideum) and bends upwards in the lateral lemniscus of the other side (Fig. 580) to end in the medial geniculate body of the metathalamus. From the medial geniculate body a new tract arises (composed of tertiary acoustic neurones), which passes laterally (Figs. 580 and 584) to end in the transverse temporal gyri. This tract may be called the radiatio thalamotemporalis. The area into which this acoustic radiation is inserted occupies not only the region of the anterior transverse temporal gyrus (Fig. 582) hidden within the lateral fissure, but also extends over its inferior lip, on to the exposed surface of the superior temporal gyrus (Fig. 581). Surrounding this area there are two concentric bands,. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the ori
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectanatomy, bookyear1914
