In cases where the margin of a section is transparent and free of black stains when it is held against sunlight or a bright flame, the section is carefully washed with water and poured onto with an acidic and ideally hot solution (Ac. Ocalic. 0.5, Nat. sulfuros. 0.5, Aq. 200). The section is then gently swung in the solution until the margin is perfectly white and stain free.

If necessary, the acid solution can be changed. Should stains still persist, one has either the option to be satisfied with the result or otherwise restart the process with potassium solution after washing the slice in water. A repetition is also advisable Selleck XAV-939 if the staining was very intense and the layers are thus not distinguishable after the first staining. In such a manner, de-staining can be carried to the extreme. The more de-staining is carried out the brighter the entire slice becomes. This however also applies to the delicate fibres, especially cortical fibres, which can be de-stained to the point where they will fade. If a slice that is too bright and brown it can be stained darker and blue when covered in alkaline solution, an ammonia solution or carbonic lithium. The slice – from now onwards placed on an object slide – is dried in absolute alcohol and the celloidin

is removed with ether alcohol. If the slice was covered with celloidin prior to cutting, it is best to make sure that the side of the slice that was covered with celloidin is find more placed facedown on the stage. It is then lightened in carboxylox (ac.

Carbol. 2. Xyl.6.). One drains the carboxylol a little and presses at least eight layers of blotting paper quickly and strongly on the slice. The uppermost page of blotting paper should not become wet, as parts of the slide will stick to it. The slice is then poured over with warm or Xylol-thinned Canada-balm and covered with a thin glass plate. During microscopy, it is best to look without why aperture using an Abbé microscope. The cortex, whose white matter connections are to be described here, is delimited anteriorly by a frontal plane [fr], which passes tangential to the posterior end of the splenium (Fig. 1 and 2). The natural boundary for the white matter of the occipital lobe, the confluence of the posterior horn in the cella lateralis of the lateral ventricle – the opening of the posterior horn – lies just behind this plane. On the convexity of the medial surface this plane cuts the most anterior part of the precuneus (Fig. 2). On the lateral convexity (Fig. 1) it cuts the gyrus at the end of the Sylvian fissure [supramarginal gyrus], whose most posterior cortical indentation extents into the depths. On the lateral convexity of this three-sided piece of brain, two sulci can be seen running dorso-ventrally [e,k], and three sulci running posterior-anteriorly [s.o. I-III], which all impact on the shape of the underlying white matter due to their depth.