scholarly journals Asymmetry and sexual dimorphism of the medial frontal gyrus visible surface in humans

2010 ◽  
Vol 67 (2) ◽  
pp. 123-127
Author(s):  
Goran Spasojevic ◽  
Zlatan Stojanovic ◽  
Dusan Suscevic ◽  
Slobodan Malobabic ◽  
Saso Rafajlovski ◽  
...  
Keyword(s):  
Sexual Dimorphism ◽  
Brain Size ◽  
Genetic Studies ◽  
Brain Hemispheres ◽  
Morphological Asymmetry ◽  
Medial Frontal Gyrus ◽  
The Difference ◽  
The Right ◽  
The Brain ◽  
Human Nervous System

Background/Aim. Studies of visible (extrasulcal) surface of the brain hemispheres are not feasible for measurements of the brain size, but are valuable for analysis and quantification of sexual dimorphism and/or asymmetries of the human brain. Morphological and morphometric investigations of the brain may contribute in genetic studies of the human nervous system. The aim of this study was to determine and to quantify sexual dimorphism and the right/left morphological asymmetry of the visible surface of medial frontal gyrus (gyrus frontalis medialis - GFM). Methods. Measurements and analysis of the visible surface of GFM were done on 84 hemispheres (42 brains from the persons of both sexes: 26 males and 16 females, 20-65 years of age). After fixation in 10% formalin and dissection, digital morphometric measurements were performed. We studied these in relation to the side of the hemisphere and the person's sex. Standardized digital AutoCAD planimetry of the visible surface of GFM was enabled by the use of coordinate system of intercommissural line. Results. In the whole sample, the visible surface of the right GFM (21.39 cm2) was statistically significantly greater (p < 0.05) than the left GFM (18.35 cm2) indicating the right/left asymmetry of the visible surface of GFM. Also, the visible surface of the right GFM in the males (22.66 cm2) was significantly greater (p < 0.05) than in the females (19.35 cm2), while the difference in size of the left GFM between the males and the females was not significant (p > 0.05). Conclusion. Morphological analysis of visible surface of GFM performed by digital planimetry showed sexual dimorphism of the visible surface and the presence of right/left asymmetry of GFM.

scholarly journals Brain Size of the African Grasscutter (Thryonomys Swinderianus, Temminck, 1827) at Defined Postnatal Periods

2017 ◽  
Vol 61 (4) ◽  
pp. 5-11 ◽  
Author(s):  
C. S. Ibe ◽  
S. O. Salami ◽  
N. Wanmi
Keyword(s):  
Cognitive Ability ◽  
Brain Size ◽  
Natural Habitat ◽  
Brain Weight ◽  
Strong Positive Correlation ◽  
Positive Correlation ◽  
Thryonomys Swinderianus ◽  
Physiological Studies ◽  
The Difference ◽  
The Brain

Abstract As a sequel to the current advancement in ethology, this study was designed to provide information on the brain size of the African grasscutter at specific postnatal periods and to extrapolate these findings to the behaviour of the rodent in its natural habitat. Brain samples were extracted from African grasscutter neonates on postnatal day 6, juveniles on postnatal day 72 and adults on postnatal day 450 by basic neuro-anatomical techniques. The weight, volume and dimensions of the brain samples were determined in absolute and relative terms. Their encephalisation quotient was also computed. There was a very strong positive correlation between nose-rump length and brain length in the neonates. The relative brain weight of neonates, juveniles and adults were 3.84 ± 0.12 %, 2.49 ± 0.07 % and 0.44 ± 0.03 %, respectively. The differences were significant (P < 0.05). The encephalisation quotient of juveniles was 1.62 ± 0.03 while that of the adult was 0.49 ± 0.02. The difference was significant (P < 0.05). The results were extrapolated to the animal’s cognitive ability, and compared with other rodents. It was concluded that the juvenile African grasscutter may have higher cognitive ability than the adult rodent, thus, juveniles should be preferred in physiological studies of memory and cognition.

scholarly journals A Study of the Duration of Controlled Speech in Right Hemisphere of the Brain Damaged Male Participants

2021 ◽  
Vol 2 (2) ◽  
pp. 1-8
Author(s):  
Agniva Pal ◽  
Keyword(s):  
Right Hemisphere ◽  
Adult Males ◽  
Age And Gender ◽  
Linguistic Research ◽  
The Difference ◽  
Normal Males ◽  
And Gender ◽  
The Right ◽  
The Brain ◽  
Normal Controls

This is a neuro-linguistic research which compares Bangla speaking right hemisphere damaged (furthermore to be called RHD) male participants to age and gender matched normal males who have been selected from the same family as the right hemisphere damaged participants. RHD or right hemisphere damaged participants are those who have lesions or damages in the right hemisphere of the brain or both. This paper pertains to the understanding how a lesion or a damage in the right hemisphere can cause changes in the pattern of communication of adult males in the age group of 45 to 70. This paper discerns the difference in durations of controlled speech in RHD males compared to age and gender matched normal controls. It will be measured with the help a predetermined passage. A passage will be played to them, using a media player (to make sure everyone listens to the same recording, ruling out chances of error there) and then they will be asked to repeat the same passage, as much as they can remember. In this research, we will be looking at the time they would take to narrate the whole passage without missing out on anything.

scholarly journals Hemispheric Organization of Visual Word Recognition in Turkish Monolinguals

2019 ◽  
Vol 25 (2) ◽  
pp. 214-233
Author(s):  
Filiz Mergen ◽  
Gulmira Kuruoglu
Keyword(s):  
Word Recognition ◽  
Visual Word Recognition ◽  
Lexical Processing ◽  
Right Hemisphere ◽  
Response Times ◽  
Visual Word ◽  
Decision Task ◽  
Brain Hemispheres ◽  
The Right ◽  
The Brain

Recently obtained data from interdisciplinary research has expanded our knowledge on the relationship between language and the brain considerably. Numerous aspects of language have been the subject of research. Visual word recognition is a temporal process which starts with recognizing the physical features of words and matching them with potential candidates in the mental lexicon. Word frequency plays a significant role in this process. Other factors are the similarities in spelling and pronunciation, and whether words have meanings or are simply letter strings. The emotional load of the words is another factor that deserves a closer inspection as an overwhelming amount of evidence supports the privileged status of emotions both in verbal and nonverbal tasks. It is well-established that lexical processing is handled by the involvement of the brain hemispheres to varying degrees, and that the left hemisphere has greater involvement in verbal tasks as compared to the right hemisphere. Also, the emotional load of the verbal stimuli affects the specialized roles of the brain hemispheres in lexical processing. Despite the abundance of research on processing of words that belong to languages from a variety of language families, the number of studies that investigated Turkish, a language of Uralic-Altaic origin, is scarce. This study aims to fill the gap in the literature by reporting evidence on how Turkish words with and without emotional load are processed and represented in the brain. We employed a visual hemifield paradigm and a lexical decision task. The participants were instructed to decide if the letter strings presented either from the right or the left of the computer screen were real words or non-words. Their response times and accuracy of their answers were recorded. We obtained shorter response times and higher accuracy rates for real words than non-words as reported in the majority of studies in the literature. We also found that the emotional load modulated the recognition of words, supporting the results in the literature. Finally, our results are in line with the view of left hemispheric superiority in lexical processing in monolingual speakers.

scholarly journals OCENA DYMORFIZMU PŁCIOWEGO WSKAŹNIKA DŁUGOŚCI PALCÓW (2D:4D)

2016 ◽  
Vol 60 (1) ◽  
Author(s):  
Maciej Mularczyk ◽  
Angelika Ziętek-Czeszak ◽  
Zbigniew Ziętek
Keyword(s):  
Sexual Dimorphism ◽  
Statistical Significance ◽  
Length Ratio ◽  
Significance Level ◽  
Finger Length ◽  
Fourth Finger ◽  
Males And Females ◽  
The Difference ◽  
The Right ◽  
Finger Length Ratio

Introduction: Studies on many populations have shown that the length of the second finger (2D) compared to the fourth (4D), expressed as the finger length ratio (2D:4D), might be characteristic for sexual dimorphism. It was also found that the values of 2D:4D differ significantly between examined populations. It is thought that the value of 2D:4D is determined in early foetal life under the influence of genetic factors and the strong influence of sex hormones. It has been proven that the values of 2D:4D are related to, for instance, sexual orientation, and artistic and sporting ability. Recently, increasing interest in the clinical significance of finger length ratio in the diagnosis of somatic and mental disorders has been observed. For example, it was found that values of 2D:4D in individuals suffering from congenital adrenal hyperplasia or autism were significantly lower compared to healthy subjects. The aim of the study was to determine sexual dimorphism in finger length ratio among representatives of the Polish population.Materials and methods: The study group comprised 115 people (57 females and 58 males). Anthropometric measurements were taken from the second and fourth finger of the right and left hands – from the point of dactylion (da) to pseudophalangion (pph) using analogue callipers. We calculated the significance of differences in 2D:4D between males and females separately for the right and left hands.Results: In both hands mean 2D:4D values were lower in males than in females. The difference in the right hand reached the statistical significance level with p < 0.05.Conclusions: Among the subjects from the examined population the 2D:4D ratio shows trends characteristic for sexual dimorphism.

scholarly journals Development of Brain Balancing System for Left and Right Hemispheres

2021 ◽  
Vol 3 ◽  
pp. 1-7
Author(s):  
Karen Chua ◽  
Zheng You Lim ◽  
Kok Swee Sim ◽  
Shing Chiang Tan
Keyword(s):  
Right Hemisphere ◽  
Exercise Program ◽  
Color Code ◽  
Brain Dominance ◽  
Brain Hemispheres ◽  
Left Hand ◽  
Before And After ◽  
Left And Right ◽  
The Difference ◽  
The Brain

This paper presents the design of Mini Brain Games (MBGs) to improve either the left or right hemisphere of the brain. The MBG includes spot the difference, piano, block view, word building, word scrambler, sudoku, left hand control, memory card, flash card, crossword, math logic and mnemonics technique used for the order of operations in algebra, the planets in solar system, and resistor color code. Stroop test and brain dominance test are used to measure the level of balance between the two hemispheres of the brain before and after the exercise program. The mini brain games designed in the Brain Balancing System Windows Application are shown to improve the balance between the left and right hemisphere of the brain. The results show that the mini brain games are indeed able to assist in the left or right brain development. The largest improvement achieved is that the percentage of dominance between the two brain hemispheres is reduced by 18.18%. The smallest improvement achieved was that the difference between the two brain hemispheres was reduced by 9.08%.

scholarly journals BRAIN VOLUMES OF THE LAMB, RAT AND BIRD DO NOT SHOW HEMISPHERIC ASYMMETRY: A STEREOLOGICAL STUDY

2011 ◽  
Vol 20 (1) ◽  
pp. 9 ◽  
Author(s):  
Bünyamin Sahin ◽  
Hüseyin Aslan ◽  
Bünyami Unal ◽  
Sinan Canan ◽  
Sait Bilgic ◽  
...  
Keyword(s):  
Statistical Significance ◽  
Volume Estimation ◽  
Brain Volumes ◽  
Brain Hemispheres ◽  
Surface Areas ◽  
Cavalieri Principle ◽  
Left Brain ◽  
Functional Differences ◽  
The Right ◽  
The Brain

It is well known that there are functional differences between right and left brain hemispheres. However, it is not clear whether these functional differences are reflected in morphometric differences. This study was carried out to investigate the right-left asymmetry, and sex and species differences of the brains using the Cavalieri principle for volume estimation. Seventeen lambs, 10 rats and 12 avian brains were used to estimate brain volumes. A transparent point grid was superimposed on the slices of lamb brains directly and the slices of the rat and avian brains were projected onto a screen at 10x magnification. Surface areas of the cut slice faces were estimated by simply counting the points that hit the slices. Mean brain volumes were 37.74 cm3, 598.95 mm3 and 730.38 mm3 and the coefficients of variations were 0.08, 0.05 and 0.05 for lamb, rat and avian brains respectively. The differences between left and right hemispheres did not show statistical significance (P > 0.05). However, the male brain volumes were larger than the females for the lamb and bird (P < 0.05). In light of such findings, it will be necessary to evaluate neuron number of the brain hemispheres to provide more useful data regarding inter-hemispheric brain asymmetry.

scholarly journals Asymmetric visual input and route recapitulation in homing pigeons

2015 ◽  
Vol 282 (1816) ◽  
pp. 20151957 ◽  
Author(s):  
Antone Martinho ◽  
Dora Biro ◽  
Tim Guilford ◽  
Anna Gagliardo ◽  
Alex Kacelnik
Keyword(s):  
Global Positioning System ◽  
Columba Livia ◽  
Neural Systems ◽  
Brain Hemispheres ◽  
Visual Inputs ◽  
Global Positioning ◽  
Behavioural Consequence ◽  
Left And Right ◽  
The Right ◽  
The Brain

Pigeons ( Columba livia ) display reliable homing behaviour, but their homing routes from familiar release points are individually idiosyncratic and tightly recapitulated, suggesting that learning plays a role in route establishment. In light of the fact that routes are learned, and that both ascending and descending visual pathways share visual inputs from each eye asymmetrically to the brain hemispheres, we investigated how information from each eye contributes to route establishment, and how information input is shared between left and right neural systems. Using on-board global positioning system loggers, we tested 12 pigeons' route fidelity when switching from learning a route with one eye to homing with the other, and back, in an A-B-A design. Two groups of birds, trained first with the left or first with the right eye, formed new idiosyncratic routes after switching eyes, but those that flew first with the left eye formed these routes nearer to their original routes. This confirms that vision plays a major role in homing from familiar sites and exposes a behavioural consequence of neuroanatomical asymmetry whose ontogeny is better understood than its functional significance.

Asymmetrische Hirndurchblutung im Alter?

1976 ◽  
Vol 15 (05) ◽  
pp. 217-222
Author(s):  
A. Bekier
Keyword(s):  
False Positive ◽  
Brain Perfusion ◽  
Scintillation Camera ◽  
Medicine Department ◽  
Brain Hemispheres ◽  
Perfusion Studies ◽  
The Right ◽  
The Brain ◽  
Positive Results ◽  
Brain Study

Between 1971 and 1975 we performed 1580 dynamic perfusion studies in 1411 patients. The patients were admitted to the nuclear medicine department for brain scanning from the medical, neurological and neurosurgical departments as well as directly by private family physicians.For dynamic brain studies we used the scintillation camera (Searle Radiographics) and a bolus of 99mTc-pertechnetate intravenously injected. The polaroid frames were exposed at 4 second intervalsThe results of the dynamic brain study were divided into five categories: normal, moderately diminished perfusion of one hemisphere, severe perfusion defect of one hemisphere, focal or multifocal hypervascular areas (“hot areas”) and stenosis or occlusion of the carotid artery.In 1009 cases we found a normal perfusion of the tracer material without any side difference between the brain hemispheres.In 68 patients with motoric hemisyndrome of the right side and in 89 patients with hemisyndrome of the left side we were able to demonstrate a diminished perfusion of the contralateral hemisphere.In 65 patients with confirmed primary or metastatic brain tumors we observed a perfusion deficiency in 39 cases and focal “hot” areas in 26 cases.In 24 epileptic patients we found asymmetrical perfusion of the brain.In 109 patients without any neurological signs or symptoms we registered a “false positive” dynamic perfusion study with an asymmetrical initial transition of the injected tracer material.The left hemisphere showed a diminished perfusion in 86 cases, the right in 23 cases.The asymmetrical brain perfusion was not observed in patients under the age of twenty years.The incidence of “false positive” dynamic brain studies was found to be dependent on the age of the investigeted patients with a maximum of asymmetrical brain perfusion scans in the age group between 61 and 70 years.At present time we are not able to explain the reason of the “false positive” results. Because of this reason the investigation will be continued together with the neurologists and radiologists to find out a possible correlation between our study, the EEG-curves and results of the morphological brain investigations such as pneumoencephalography or ACT-scans.

scholarly journals Neuropsychological Changes Following Carotid Endarterectomy

1981 ◽  
Vol 8 (2) ◽  
pp. 127-132 ◽  
Author(s):  
Robert A. Bornstein ◽  
Brien G. Benoit ◽  
Ronald L. Trites
Keyword(s):  
Carotid Endarterectomy ◽  
Control Group ◽  
Neuropsychological Battery ◽  
Stroke Patients ◽  
Neuropsychological Changes ◽  
The Difference ◽  
Underlying Mechanisms ◽  
The Right ◽  
The Brain ◽  
Cerebrovascular Symptoms

SUMMARY:Fifty-five subjects undergoing carotid endarterectomy were grouped according to side of operation, i.e. right, left and bilateral. These subjects were administered a comprehensive neuropsychological battery prior to and six months following surgery. The performance of these subjects was compared with a control group undergoing surgical procedures that did not in volve the brain or cerebral vasculature, and a second control group composed of patients with cerebrovascular symptoms who were not operated. It was found that as a group the endarterectomy subjects improved on a greater percentage of measures. When various subgroups were examined, it was found that the right operated stroke patients improved on significantly more measures than any other group. The difference between right and left stroke patients was significant, but there was no difference between right and left TIA patients in the extent of improvement. These findings were discussed in terms of possible underlying mechanisms.

scholarly journals On the perception of the direction of sound

1909 ◽  
Vol 83 (559) ◽  
pp. 61-64 ◽  
Keyword(s):  
Phase Difference ◽  
Laboratory Experiments ◽  
The Difference ◽  
The Right ◽  
The Brain

The nature of the clue by which we are able to pronounce whether a sound of low pitch reaches us from the right or form the left was long a mystery, seeing that in such cases the difference of intensities at two ears, used singly, is inappreciable. By some special laboratory experiments conducted about three years ago, I was able to show that the discrimination depends upon the phase -difference at the two ears, and the sound is judged to be on that side where the phase is in advance . When the pitch is higher (much above g ') no distinct lateral effect accompanies a phase-difference, and the discrimination of right and left in ordinary hearing undoubtedly depends upon intensities. Commenting on these results, I remarked (p. 224): "The conclusion, no longer to be resisted, that when a sound of low pitch reaches the two ears with approximately equal intensities, but with a phase-difference of a quarter of a period, we are able so easily to distinguish at which ear the phase is in advance, must far-reaching consequences in the theory of audition. It seems no longer possible to hold that the vibratory character of sound terminates at the outer ends of the nerves along which the communication with the brain is established. On the contrary, the processes in the nerve must themselves be vibratory, not, of course, in the gross mechanical sense, but with preservation of the period and retaining the characteristic of phase-a view advocated by Rutherford, in opposition to Helmholtz, as long as 1886."

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