scholarly journals Το νευροβιολογικό υπόστρωμα της νοημοσύνης: Ανατομικά και λειτουργικά χαρακτηριστικά του εγκεφάλου που συνδέονται με γνωστικές ικανότητες

2020 ◽  
Vol 22 (1) ◽  
pp. 14
Author(s):  
Δήμητρα-Μαρία Τόμπρου ◽  
Ελένη Ντόλκα ◽  
Μαριέττα Παπαδάτου-Παστού
Keyword(s):  
Nerve Conduction Velocity ◽  
Brain Volume ◽  
Integration Theory ◽  
Cerebral Laterality ◽  
Anatomical Features ◽  
Theories Of Intelligence ◽  
White Matter Microstructure ◽  
Neural Efficiency ◽  
Modern Era ◽  
The Brain

The modern era of brain imaging has enabled the direct investigation of the neurobiological substrate of intelligence thus contributing significantly to our understanding of individual differences in cognitive functions. This is a review of recent findings on the anatomical and functional underpinnings of intelligence. Specifically, the anatomical features of the brain that are associated with intelligence are brain volume, cortical thickness, white matter microstructure, and corpus callosum thickness. The functional characteristics associated with intelligence are the degree of activation of the prefrontal cortex and other areas of the parieto-frontal network, nerve conduction velocity, rate of glucose metabolism, and direction of cerebral laterality. Two recent neurobiological theories of intelligence, namely the neural efficiency hypothesis and the parieto-frontal integration theory (P-FIT), are also presented.

On the anatomic relation of choroid plexus to brain: a comparative study

1980 ◽  
Vol 238 (1) ◽  
pp. R76-R81 ◽  
Author(s):  
H. F. Cserr ◽  
M. Bundgaard ◽  
J. K. Ashby ◽  
M. Murray
Keyword(s):  
Choroid Plexus ◽  
Brain Volume ◽  
Brain Size ◽  
Ventricular Volume ◽  
Brain Weight ◽  
Air Breathing ◽  
Original Proposal ◽  
Adaptive Value ◽  
Choroid Plexuses ◽  
The Brain

The size of choroid plexuses and cerebral ventricles relative to brain varies widely among vertebrates. The functional significance of this variability has attracted little attention since Herrick's original proposal that large choroid plexuses might enhance oxygen delivery to the brain and therefore be of adaptive value in the transition of vertebrates from water to air breathing. We compared choroid plexus and brain weight or ventricular and brain volume in 40 species from nine vertebrate groups. Both choroid plexus weight and ventricular volume were unrelated to brain size. Plexus weight ranged from 0 to 5.2% of brain weight and ventricular volume from 0.9 to 132% of brain volume. Amid this diversity the dipnoans, chondrosteans, holosteans, amphibians, and crossopterygian examined in this study are exceptional in uniformly having large plexuses. The adaptive significance of large choroid plexuses may lie in the presence of specific homeostatic mechanisms and their role in the response to the increases in PCO2 that accompany the transition to air breathing.

scholarly journals The Effect of Intraventricular Hemorrhage on Brain Development in Premature Infants: A Synthetic MRI Study

2021 ◽  
Vol 12 ◽  
Author(s):  
Chunxiang Zhang ◽  
Xin Zhao ◽  
Meiying Cheng ◽  
Kaiyu Wang ◽  
Xiaoan Zhang
Keyword(s):  
Relaxation Time ◽  
Premature Infants ◽  
Intraventricular Hemorrhage ◽  
Brain Volume ◽  
Relaxation Times ◽  
T2 Relaxation Time ◽  
T2 Relaxation ◽  
T1 And T2 ◽  
The Brain ◽  
Synthetic Mri

Objectives: Synthetic MRI can obtain multiple parameters in one scan, including T1 and T2 relaxation time, proton density (PD), brain volume, etc. This study aimed to investigate the parameter values T1 and T2 relaxation time, PD, and volume characteristics of intraventricular hemorrhage (IVH) newborn brain, and the ability of synthetic MRI parameters T1 and T2 relaxation time and PD to diagnose IVH.Materials and methods: The study included 50 premature babies scanned with conventional and synthetic MRI. Premature infants were allocated to the case group (n = 15) and NON IVH (n = 35). The T1, T2, PD values, and brain volume were obtained by synthetic MRI. Then we assessed the impact of IVH on these parameters.Results: In the posterior limbs of the internal capsule (PLIC), genu of the corpus callosum (GCC), central white matter (CWM), frontal white matter (FWM), and cerebellum (each p < 0.05), the T1 and T2 relaxation times of the IVH group were significantly prolonged. There were significant differences also in PD. The brain volume in many parts were also significantly reduced, which was best illustrated in gray matter (GM), cerebrospinal fluid and intracranial volume, and brain parenchymal fraction (BPF) (each p < 0.001, t = −5.232 to 4.596). The differential diagnosis ability of these quantitative values was found to be excellent in PLIC, CWM, and cerebellum (AUC 0.700–0.837, p < 0.05).Conclusion: The quantitative parameters of synthetic MRI show well the brain tissue characteristic values and brain volume changes of IVH premature infants. T1 and T2 relaxation times and PD contribute to the diagnosis and evaluation of IVH.

scholarly journals BrainFD: Measuring the Intracranial Brain Volume With Fractal Dimension

2021 ◽  
Vol 13 ◽  
Author(s):  
Ghulam Md Ashraf ◽  
Stylianos Chatzichronis ◽  
Athanasios Alexiou ◽  
Nikolaos Kyriakopoulos ◽  
Badrah Saeed Ali Alghamdi ◽  
...  
Keyword(s):  
Fractal Dimension ◽  
Brain Volume ◽  
Heterogeneous Data ◽  
Imaging Biomarker ◽  
Volume Loss ◽  
Imaging Data ◽  
Clinical Dementia Rating ◽  
Brain Volume Loss ◽  
Brain White Matter ◽  
The Brain

A few methods and tools are available for the quantitative measurement of the brain volume targeting mainly brain volume loss. However, several factors, such as the clinical conditions, the time of the day, the type of MRI machine, the brain volume artifacts, the pseudoatrophy, and the variations among the protocols, produce extreme variations leading to misdiagnosis of brain atrophy. While brain white matter loss is a characteristic lesion during neurodegeneration, the main objective of this study was to create a computational tool for high precision measuring structural brain changes using the fractal dimension (FD) definition. The validation of the BrainFD software is based on T1-weighted MRI images from the Open Access Series of Imaging Studies (OASIS)-3 brain database, where each participant has multiple MRI scan sessions. The software is based on the Python and JAVA programming languages with the main functionality of the FD calculation using the box-counting algorithm, for different subjects on the same brain regions, with high accuracy and resolution, offering the ability to compare brain data regions from different subjects and on multiple sessions, creating different imaging profiles based on the Clinical Dementia Rating (CDR) scores of the participants. Two experiments were executed. The first was a cross-sectional study where the data were separated into two CDR classes. In the second experiment, a model on multiple heterogeneous data was trained, and the FD calculation for each participant of the OASIS-3 database through multiple sessions was evaluated. The results suggest that the FD variation efficiently describes the structural complexity of the brain and the related cognitive decline. Additionally, the FD efficiently discriminates the two classes achieving 100% accuracy. It is shown that this classification outperforms the currently existing methods in terms of accuracy and the size of the dataset. Therefore, the FD calculation for identifying intracranial brain volume loss could be applied as a potential low-cost personalized imaging biomarker. Furthermore, the possibilities measuring different brain areas and subregions could give robust evidence of the slightest variations to imaging data obtained from repetitive measurements to Physicians and Radiologists.

scholarly journals Sleep apnoea in the asymptomatic elderly: a real issue for the brain?

2018 ◽  
Vol 51 (6) ◽  
pp. 1702450 ◽  
Author(s):  
Sébastien Celle ◽  
Claire Boutet ◽  
Cédric Annweiler ◽  
Jean-Claude Barthélémy ◽  
Frédéric Roche
Keyword(s):  
Cortical Thickness ◽  
Brain Volume ◽  
Sleep Apnoea ◽  
Middle Temporal Gyrus ◽  
Elderly Subjects ◽  
Brain Volumes ◽  
Control Subjects ◽  
Surface Control ◽  
The Brain ◽  
Local Brain

The link between sleep apnoea and brain structure is unclear; although dysfunction of the hippocampus, middle temporal gyrus and brainstem/cerebellum have been observed previously. However, this link has been little explored in elderly subjects. The aim of this study was to explore the link between sleep apnoea and the brain in an elderly population.226 asymptomatic elderly subjects (age mean±sd 75.3±0.9 years, range 72.3–77.8 years) from the PROOF (Evaluation of Ageing, Autonomic Nervous System Activity and Cardiovascular Events) cohort study were explored using linear voxel-based or cortical thickness with apnoea/hypopnoea index (AHI; mean±sd 15.9±11.5 events·h−1, range 6–63.6 events·h−1) as a covariate of main interest. The brain volumes of 20 control subjects, 18 apnoeic (AHI >29 events·h−1) treated patients and 20 apnoeic untreated patients from this population were compared using voxel-based morphometry, cortical thickness or surface-based analyses.AHI was not associated with any change in local brain volume, cortical thickness or cortex surface. Control subjects, apnoeic treated and untreated patients were not different in terms of local brain volume, cortical thickness or surface.In a specific population of asymptomatic elderly healthy subjects, sleep apnoea does not seem to be associated with a change in local brain volume or in cortical thickness.

Novel Multi-Linear Quantitative Brain Volume Formula For Manual Radiological Evaluation Of Brain Atrophy

2020 ◽  
Author(s):  
Richard Erasto Sungura ◽  
Emmanuel Abraham Mpolya ◽  
JM Spitsbergen ◽  
Callen Kwamboka Onyambu ◽  
Elingarami Sauli ◽  
...  
Keyword(s):  
Brain Atrophy ◽  
Quantitative Methods ◽  
Brain Volume ◽  
Northern Tanzania ◽  
Alternative Formula ◽  
Evans Index ◽  
Radiological Measurements ◽  
Technical Simplicity ◽  
Radiological Methods ◽  
The Brain

Abstract Background The brain is a dynamic organ that develops and involutes in volume. The process of volume loss known as brain atrophy commonly occurs in elderly. However, some conditions have been implicated to provoke this paradoxical process in childhood and making it important to have methods and techniques of quantifying brain volume. Automated quantitative methods are very important in brain atrophy assessment but these tools have limited availability in developing countries. The simplified linear radiological methods are poorly reproducible and hence there is a need to develop an alternative formula that is reproducible and applicable at all healthcare levels. Methods The multi-linear diagonal brain fraction formula (DBF) was designed from dimensions of brain relative to skull. To test a developed formula, a total of 347 subjects aged between 0 and 18 years who had brain CT scans performed at the health facilities in Northern Tanzania were recruited and subjected to a systematic measurement of their brains in a diagonal brain fashion. Results Out of 347 patients evaluated, 62 subjects (17.8%) were found to be cases of brain atrophy. The three radiological measurements which included sulcal width (SW), ventricular width (VW) and Evans Index (EI) were concurrently performed. SW and VW showed good age correlation while EI showed no significant correlation with age. Similar tests were extended to diagonal brain fraction (DBF) and skull vertical horizontal ratio (VHR) in which DBF showed significant correlation. Conclusions The DBF formula shows significant ability of differentiating changes of brain volume suggesting that it can be utilized as an alternative brain fraction quantification method bearing technical simplicity in assessing gross brain volume with the ability to classify degrees of brain atrophy into mild, moderate, severe and very severe stages.

The history of neurosurgery

2019 ◽  
pp. 3-10
Author(s):  
Henry Marsh ◽  
Eleni Marts
Keyword(s):  
Head Injuries ◽  
Neurosurgical Procedures ◽  
History Of Surgery ◽  
Localization Theory ◽  
The World ◽  
History Of Neurosurgery ◽  
History Of ◽  
Cerebral Localization ◽  
Modern Era ◽  
The Brain

The history of neurosurgery falls naturally into the premodern era, where it is essentially the history of surgery to the skull and of head injuries, and the modern era, where it is the history of surgery to the brain itself, made possible by cerebral localization theory, antisepsis, and anaesthesia, all of which developed in the nineteenth century. The first known neurosurgical procedures were skull trephines, seemingly carried out on both the living and the dead. It is unclear whether these were performed for therapeutic or ritualistic reasons. There are many trepanned skulls dating back thousands of years to the Neolithic era, and perhaps to even earlier, from sites all over the world.

Making Brains run Faster: are they Becoming Smarter?

2016 ◽  
Vol 19 ◽  
Author(s):  
Anja Pahor ◽  
Norbert Jaušovec
Keyword(s):  
Large Scale ◽  
Electric Activity ◽  
Attentional Focus ◽  
Theories Of Intelligence ◽  
Transcranial Alternating Current Stimulation ◽  
Neural Efficiency ◽  
Individual Alpha Frequency ◽  
Induced Changes ◽  
The Relationship ◽  
Raven’S Matrices

AbstractA brief overview of structural and functional brain characteristics related to g is presented in the light of major neurobiological theories of intelligence: Neural Efficiency, P-FIT and Multiple-Demand system. These theories provide a framework to discuss the main objective of the paper: what is the relationship between individual alpha frequency (IAF) and g? Three studies were conducted in order to investigate this relationship: two correlational studies and a third study in which we experimentally induced changes in IAF by means of transcranial alternating current stimulation (tACS). (1) In a large scale study (n = 417), no significant correlations between IAF and IQ were observed. However, in males IAF positively correlated with mental rotation and shape manipulation and with an attentional focus on detail. (2) The second study showed sex-specific correlations between IAF (obtained during task performance) and scope of attention in males and between IAF and reaction time in females. (3) In the third study, individuals’ IAF was increased with tACS. The induced changes in IAF had a disrupting effect on male performance on Raven’s matrices, whereas a mild positive effect was observed for females. Neuro-electric activity after verum tACS showed increased desynchronization in the upper alpha band and dissociation between fronto-parietal and right temporal brain areas during performance on Raven’s matrices. The results are discussed in the light of gender differences in brain structure and activity.

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