scholarly journals 5. Notes more especially on the Bridging Convolutions in the Brain of the Chimpanzee

1866 ◽  
Vol 5 ◽  
pp. 578-587 ◽  
Author(s):  
Wm. Turner

The late Professor Gratiolet, in his elaborate and beautifully illustrated memoir, “Sur les Plis Cérébraux de l'Homme et des Primates,” attaches great weight in his differential diagnosis of their cerebral characters to the presence or absence of one or more members of a series of convolutions, which he designates as the plis de passage. When present, these convolutions bridge over the external perpendicular fissure of the hemisphere, and connect the parietal and temporal with the occipital lobes. By various anatomists in this country they are called bridging, connecting, or annectent convolutions. In the brain of the Chimpanzee M. Gratiolet states that the first bridging convolution is altogether wanting; that the second is present, but concealed under the operculum of the occipital lobe; that the third and fourth are superficial.

2014 ◽  
Vol 5 (4) ◽  
pp. 84-88 ◽  
Author(s):  
Maryna Alfaouri-Kornieieva ◽  
Azmy M Al-Hadidi

Background: Recent clinical trials have shown a rising trend of stroke in Asian population. Approximately 20% strokes of total occur at the vertebrobasilar basin that supplies the occipital lobes of the brain, the cerebellum, and the brainstem. The anatomical features and variability of the third segment of the vertebral artery (VA) in Asians are analyzed in this study. Methods: A prospective cohort study of 68 consecutive Asian patients underwent MRA examination for head and neck in the Department of Radiology of Hospital of University of Jordan from 1.10.2011 to 30.04.2012. The 116 VA were analyzed on the obtained angiograms. Results: The third segment (V3) of the VA was studied according to its conventional division into vertical, horizontal, and oblique parts. The mean outer diameter of the V3 varied up 3.18 ± 0.73 to 4.28 ± 1.08 mm. The parameter prevailed on the left in 91% cases and was greater in males, than in females. The distal loop of the VA projected downward in 26 cases on the right (78%) and in 28 cases on the left (74%). The tortuosity of loop?formations of V3 was evaluated subject to angles between their ascending and descending bends. Conclusion: In comparison with other ethnic groups, the V3 of the VA in Asians has lesser outer diameter, especially along its oblique part; the zero?distance between the occipital bone and horizontal segment of VA occurs more often (up to 26%); the Lang’s III type of V3 variability is the most common in Asians. DOI: http://dx.doi.org/10.3126/ajms.v5i4.6150 Asian Journal of Medical Sciences 2014 Vol.5(4); 84-88


Author(s):  
Shahzadi Malhotra

The human brain is the most important as well as the most complex organ in the human body. From previous chapters, we by now know that the cerebral cortex is the part of the brain that functions to make human beings unique. Distinctly human traits including higher thought, language, and human consciousness as well as the ability to think, reason, and imagine all originate in the cerebral cortex. The cerebral cortex is the outermost portion that can be divided into the four lobes of the brain. Each bump on the surface of the brain is known as a gyrus, while each groove is known as a sulcus. In this chapter, the authors discuss the parietal and occipital lobes of the cortex. It then highlights their functional issues.


1997 ◽  
Vol 27 (2) ◽  
pp. 341-344 ◽  
Author(s):  
Jerônimo Lopes Ruas ◽  
Ana Lucia Schild ◽  
Cristina Gevehr Fernandes ◽  
João Luiz Montiel Ferreira ◽  
Gertrud Müller

Equine cerebral hydatid disease is described in a 7-year-old, crossbred, female horse. Clinical signs were characterized by circling gait, pressing of head against fences or objects and motor incoordination. On gross examination of the brain the hemispheres were swollen, mainly the left one. On transversal sections, a 5cm X 7cm fluid-filled cyst was observed within the lateral ventricle of the left hemisphere. The cyst extended from the parietal to the occipital lobe, and compressed the third ventricle. There was also marked mid line deviation. Histologically, the brain lesion adjacent to the cyst, was characterized by a piogranulomatous process and vacuolization of neuropil. A diagnosis of equine hydatidosis caused by Echinococcus granulosus was made on the basis of the morphometric features of protoscolices hooks.


2000 ◽  
Vol 20 (10) ◽  
pp. 1502-1507 ◽  
Author(s):  
Jullie W. Pan ◽  
Douglas L. Rothman ◽  
Kevin L. Behar ◽  
Daniel T. Stein ◽  
Hoby P. Hetherington

Ketones are known to constitute an important fraction of fuel for consumption by the brain, with brain ketone content generally thought to be low. However, the recent observation of 1-mmol/L levels of brain β-hydroxybutyrate (BHB) in children on the ketogenic diet suggests otherwise. The authors report the measurement of brain BHB and lactate in the occipital lobe of healthy adults using high field (4-T) magnetic resonance spectroscopy, measured in the nonfasted state and after 2-and 3-day fasting-induced ketosis. A 9-mL voxel located in the calcarine fissure was studied, detecting the BHB and lactate upfield resonances using a 1H homonuclear editing sequence. Plasma BHB levels also were measured. The mean brain BHB concentration increased from a nonfasted level of 0.05 ± 0.05 to 0.60 ± 0.26 mmol/L (after second day of fasting), increasing further to 0.98 ± 0.16 mmol/L (after the third day of fasting). The mean nonfasted brain lactate was 0.69 ± 0.17 mmol/L, increasing to 1.47 ± 0.22 mmol/L after the third day. The plasma and brain BHB levels correlated well ( r = 0.86) with a brain–plasma slope of 0.26. These data show that brain BHB rises significantly with 2-and 3-day fasting-induced ketosis. The lactate increase likely results from ketones displacing lactate oxidation without altering glucose phosphorylation and glycolysis.


1962 ◽  
Vol 40 (2) ◽  
pp. 254-262 ◽  
Author(s):  
H. H. Bassøe ◽  
R. Emberland ◽  
E. Glück ◽  
K. F. Støa

ABSTRACT The steroid excretion and the plasma corticosteroids were investigated in three patients with necrosis of the brain and of the pituitary gland. The patients were kept alive by artificial ventilation. In two of the patients the neutral 17-ketosteroids and the 17-hydrocorticosteroids fell to extremely low levels. At the same time, the number of eosinophil cells showed a tendency to increase. Corticotrophin administered intravenously twice to the third patient had a stimulating effect on the adrenal cortex. The theoretical and practical significance of these findings is discussed.


Author(s):  
Walter Ott

Despite its difference in aspiration, the Meditations preserves the basic structure of perceptual experience outlined in Descartes’s earliest works. The chapter explores Descartes’s notion of an idea and uses a developmental reading to clear up the mystery surrounding material falsity. In the third Meditation, our protagonist does not yet know enough about extension in order to be able to tell whether her idea of cold is an idea of a real feature of bodies or merely the idea of a sensation. By the time she reaches the end of her reflections, she has learned that sensible qualities are at most sensations. As in his earliest stages, Descartes believes that the real work of perceiving the geometrical qualities of bodies is done by the brain image, which he persists in calling an ‘idea,’ at least when it is the object of mental awareness.


1971 ◽  
Vol 49 (1) ◽  
pp. 129-131 ◽  
Author(s):  
F. S. Abbott ◽  
M. B. Favreau

Thirty-eight Fundulus heteroclitus were tested for ability to adapt to white and black backgrounds. They were then hypophysectomized and distributed individually to white and black containers. Their ability to adapt to background was determined for periods up to 2 weeks. Sixteen operated fish retained their preoperative ability to adapt; 8 became dark temporarily; 14 became persistently dark. Histological examination confirmed the result of the operation. In the third group of fish the persistent darkness was not associated with damage to specific areas of the brain although damage was more widespread in this group. It is concluded that hypophysectomy does not interfere with physiological color change in F. heteroclitus. The location of the central relays in the melanophore system could not be determined.


1984 ◽  
Vol 29 (2) ◽  
pp. 132-134 ◽  
Author(s):  
L.B. Raschka

Most violence connected with sleep disorder is assumed to be related to sleep walking. It is less well known that other sleep disorders can also give rise to violence. The role of narcolepsy in car accidents is mentioned. Sleep drunkenness can lead to confusion resulting in violent behaviour especially on forced awakening. This condition is associated to sleep apnea. Primary or central sleep apnea is caused by disorders of the brain stem affecting the respiratory center. Secondary or upper airway sleep apnea can be caused by virtually any condition that results in cessation of the airflow due to occlusion of the upper airway. The author describes one patient who engaged in assaultive behaviour on forced awakening following earlier alcohol consumption. The pathomechanism of violent behaviour generated by a combination of sleep apnea and respiratory pathology is described. The differential diagnosis, prevention and treatment is outlined. The use of polysomnography in diagnosis and the potentially dangerous effects of drugs with respiratory depressing effects is highlighted.


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