Cortical Brain Functions ­ The Brodmann Legacy in the 21st Century

In 1909, Korbinian Brodmann described 52 functional brain areas, 43 of them found in the human brain. More than a century later, his devoted functional map was incremented by Glasser et al in 2016, using functional nuclear magnetic resonance imaging techniques to propose the existence of 180 functional areas in each hemisphere, based on their cortical thickness, degree of myelination (cortical myelin content), neuronal interconnection, topographic organization, multitask answers, and assessment in their resting state. This opens a huge possibility, through functional neuroanatomy, to understand a little more about normal brain function and its functional impairment in the presence of a disease.

Quantitative study on human cerebellar cortex from anatomy cadaver preparations / Estudio cuantitativo de la corteza del cerebelo humano a partir de la anatomía de preparaciones cadavéricas

Human cerebellum is important for motor coordination; muscle tones and maintaing the equilibrium of the body. In our region, limited data is available on the normal morphology of human cerebellum, whilst fresh biopsy is quite difficult to obtain. Here adult male cerebellum from cadaver anatomy preparations embalmed with 37 % formalin fixative solution for over a year are studied (n=3). After removal, right cerebellum hemisphere was sliced into cubicle then temporary soaked into 50-60 % of alcohol before being paraffinated. Two parasagittal adjacent slices from each sample were deparaffinated (5 µm) and then stained with hematoxyllin-eosin (HE). Slides were observed under light microscope (Olympus, Japan). Pictures were analysed from 6 field numbers of each, with Optilab and Image Raster 3 software (Indonesia). The density of the Purkinje cells (Neuron purkinjense), the number and density of the Purkinje cells and the thickness of the molecular layer are measured. Data were analysed with the level of significance of p<0.05 (ANOVA, Microsoft Excel 2007). The distance between 2 Purkinje cells is ranged between 82.6-346.6 µm, although no significant differences found (p=0.1). There are no significant differences in the number and in the density of the Purkinje cells amongst samples (p=0.72 and 0.34, respectively); might be due to the similar age, sex and race of these cadavers. However, there is a significant difference in the thickness of the molecular layer (p=0.015). Variations amongst individual cerebelli are observed, with a significant different thickness in the molecular layer. The cellular composition of each cerebellum is unique, arguably correlated to the individual cerebellum activity when alive.

El cerebelo humano es importante en la coordinación motora, los tonos musculares y el mantenimiento del equilibrio del cuerpo. En nuestra región, son limitados los datos disponibles en relación a la morfología normal del cerebelo humano, por otra parte obtener una biopsia fresca es bastante difícil de obtener. Para este trabajo se utilizaron tres cerebelos adultos de sexo masculino, obtenidos a partir de cadáveres conservados con una solución de formalina al 37 % durante más de un año. Después de la separación, el hemisferio derecho del cerebelo fue seccionado en cubos que fueron posteriormente impregnados en una solución de 50-60 % de alcohol antes del proceso de parafinización. Se tomaron dos secciones parasagitales adyacentes (5 µm) de cada muestra desparafinada y luego éstas fueron teñidas con Hematoxilina-Eosina. Las muestras se observaron al microscopio óptico (Olympus, Japón). Se analizaron 6 campos por muestra con los softwares Optilab e Image Raster 3 (Indonesia). Se midieron la densidad de las neuronas purkinjenses (células de Purkinje), el número y densidad de ellas y el espesor de la capa molecular. Los datos fueron analizados con un nivel de significación de p<0,05 (ANOVA, Microsoft Excel 2007). La distancia entre dos células de Purkinje varió entre 82,6-346,6 µm, sin encontrarse diferencias significativas (p = 0,1). No hay diferencias significativas en el número (p = 0,72) y la densidad (p = 0,34) de células de Purkinje entre las muestras; podría deberse a la misma edad, el sexo y la raza de los cadáveres utilizados. Sin embargo, hay una diferencia significativa en el espesor de la capa molecular (p = 0,015). Se observaron variaciones individuales en el cerebelo, encontrándose diferencia significativa el espesor de la capa molecular. La composición celular del cerebelo es única, sin duda esta se correlaciona con la actividad del cerebelo en individuos vivos.

Estudio morfométrico comparativo de la corteza cerebelosa humana en dos grupos etarios / Comparative morphometric study of human cerebellar cortex in two age groups

Histológicamente la corteza del cerebelo humano adulto presenta tres capas constitutivas; la capa molecular, la hilera de los cuerpos de las células de Purkinje y la capa granulosa interna. La sustancia cortical del cerebelo de los embriones de mamífero, así como la de los jóvenes, muestran una capa granular externa. Nuestro objetivo es documentar las diferencias morfológicas entre las capas de la corteza cerebelosa adulta y joven. Se realizaron estudios morfométricos microscópicos en 20 cerebelos de autopsias. Los casos se dividieron en dos grupos, adultos y niños menores de 1 año. Se realizaron cortes en parafina, coloreados con hematoxilina y eosina. La corteza del cerebelo adulto presentó diferencias morfológicas con la de los recién nacidos. En el cerebelo adulto presenta tres capas constitutivas, mientras que en el recién nacido presenta una cuarta capa, la granulosa externa...

Histologically, the adult human cerebellar cortex has three constituent layers, the molecular layer, the row of bodies of Purkinje cells and internal granular layer. The cortex of the cerebellum of mammalian embryos, as well as youth, show external granular layer. Our goal is to document morphological differences between the layers of the cerebellar cortex adult and young. Microscopic morphometric studies were performed in 20 cerebellum autopsied. The cases were divided into two groups, adults and children under 1 year. Paraffin sections were performed, stained with hematoxylin and eosin. The cortex of adult cerebellum showed morphological differences of the newborn. In the adult cerebellum has three constituent layers, whereas in the newborn has a fourth layer, the external granular...

Effect of ethanol on the prenatal development of the external granular layer of the cerebellar cortex of chick embryo [light and electron microscopic study]

The effect of ethanol on the granule cells of the external granular layer of the cerebellar cortex of chick embryos was studied in Golgi preparation for light microscopy and ultra-thin sections for electron microscopy. A total of 100 fresh fertile Fayoumy eggs was used in this study and divided into two groups. A decrease was seen in the size of granule cells with ill-defined cytoplasmic processes or poorly developed few cytoplasmic processes by light microscopy. By electron microscopy, no nuclear changes were observed, but apparent cytoplasmic changes were observed in the form of absence of cytoplasmic organelles in some granule cells and poorly developed immature mitochondria, few free ribosomes and poorly developed swollen endoplasmic reticulum in other granule cells