A bigger brain for a more complex environment

2020 ◽  
Vol 31 (8) ◽  
pp. 803-816
Author(s):  
Umberto di Porzio

AbstractThe environment increased complexity required more neural functions to develop in the hominin brains, and the hominins adapted to the complexity by developing a bigger brain with a greater interconnection between its parts. Thus, complex environments drove the growth of the brain. In about two million years during hominin evolution, the brain increased three folds in size, one of the largest and most complex amongst mammals, relative to body size. The size increase has led to anatomical reorganization and complex neuronal interactions in a relatively small skull. At birth, the human brain is only about 20% of its adult size. That facilitates the passage through the birth canal. Therefore, the human brain, especially cortex, develops postnatally in a rich stimulating environment with continuous brain wiring and rewiring and insertion of billions of new neurons. One of the consequence is that in the newborn brain, neuroplasticity is always turned “on” and it remains active throughout life, which gave humans the ability to adapt to complex and often hostile environments, integrate external experiences, solve problems, elaborate abstract ideas and innovative technologies, store a lot of information. Besides, hominins acquired unique abilities as music, language, and intense social cooperation. Overwhelming ecological, social, and cultural challenges have made the human brain so unique. From these events, as well as the molecular genetic changes that took place in those million years, under the pressure of natural selection, derive the distinctive cognitive abilities that have led us to complex social organizations and made our species successful.

2012 ◽  
Vol 367 (1603) ◽  
pp. 2677-2685 ◽  
Author(s):  
Lars Chittka ◽  
Stephen J. Rossiter ◽  
Peter Skorupski ◽  
Chrisantha Fernando

To understand how complex, or ‘advanced’ various forms of cognition are, and to compare them between species for evolutionary studies, we need to understand the diversity of neural–computational mechanisms that may be involved, and to identify the genetic changes that are necessary to mediate changes in cognitive functions. The same overt cognitive capacity might be mediated by entirely different neural circuitries in different species, with a many-to-one mapping between behavioural routines, computations and their neural implementations. Comparative behavioural research needs to be complemented with a bottom-up approach in which neurobiological and molecular-genetic analyses allow pinpointing of underlying neural and genetic bases that constrain cognitive variation. Often, only very minor differences in circuitry might be needed to generate major shifts in cognitive functions and the possibility that cognitive traits arise by convergence or parallel evolution needs to be taken seriously. Hereditary variation in cognitive traits between individuals of a species might be extensive, and selection experiments on cognitive traits might be a useful avenue to explore how rapidly changes in cognitive abilities occur in the face of pertinent selection pressures.


Author(s):  
Lucía Florencia Franchini

The remarkable sensory, motor, and cognitive abilities of mammals mainly depend on the neocortex. Thus, the emergence of the six-layered neocortex in reptilian ancestors of mammals constitutes a fundamental evolutionary landmark. The mammalian cortex is a columnar epithelium of densely packed cells organized in layers where neurons are generated mainly in the subventricular zone in successive waves throughout development. Newborn cells move away from their site of neurogenesis through radial or tangential migration to reach their specific destination closer to the pial surface of the same or different cortical area. Interestingly, the genetic programs underlying neocortical development diversified in different mammalian lineages. In this work, I will review several recent studies that characterized how distinct transcriptional programs relate to the development and functional organization of the neocortex across diverse mammalian lineages. In some primates such as the anthropoids, the neocortex became extremely large, especially in humans where it comprises around 80% of the brain. It has been hypothesized that the massive expansion of the cortical surface and elaboration of its connections in the human lineage, has enabled our unique cognitive capacities including abstract thinking, long-term planning, verbal language and elaborated tool making capabilities. I will also analyze the lineage-specific genetic changes that could have led to the modification of key neurodevelopmental events, including regulation of cell number, neuronal migration, and differentiation into specific phenotypes, in order to shed light on the evolutionary mechanisms underlying the diversity of mammalian brains including the human brain.


2020 ◽  
Author(s):  
Jean-Pierre Changeux ◽  
Alexandros Goulas ◽  
Claus C Hilgetag

Abstract Cognitive abilities of the human brain, including language, have expanded dramatically in the course of our recent evolution from nonhuman primates, despite only minor apparent changes at the gene level. The hypothesis we propose for this paradox relies upon fundamental features of human brain connectivity, which contribute to a characteristic anatomical, functional, and computational neural phenotype, offering a parsimonious framework for connectomic changes taking place upon the human-specific evolution of the genome. Many human connectomic features might be accounted for by substantially increased brain size within the global neural architecture of the primate brain, resulting in a larger number of neurons and areas and the sparsification, increased modularity, and laminar differentiation of cortical connections. The combination of these features with the developmental expansion of upper cortical layers, prolonged postnatal brain development, and multiplied nongenetic interactions with the physical, social, and cultural environment gives rise to categorically human-specific cognitive abilities including the recursivity of language. Thus, a small set of genetic regulatory events affecting quantitative gene expression may plausibly account for the origins of human brain connectivity and cognition.


Author(s):  
Preecha Yupapin ◽  
Amiri I. S. ◽  
Ali J. ◽  
Ponsuwancharoen N. ◽  
Youplao P.

The sequence of the human brain can be configured by the originated strongly coupling fields to a pair of the ionic substances(bio-cells) within the microtubules. From which the dipole oscillation begins and transports by the strong trapped force, which is known as a tweezer. The tweezers are the trapped polaritons, which are the electrical charges with information. They will be collected on the brain surface and transport via the liquid core guide wave, which is the mixture of blood content and water. The oscillation frequency is called the Rabi frequency, is formed by the two-level atom system. Our aim will manipulate the Rabi oscillation by an on-chip device, where the quantum outputs may help to form the realistic human brain function for humanoid robotic applications.


Author(s):  
М.М. Руденок ◽  
А.Х. Алиева ◽  
А.А. Колачева ◽  
М.В. Угрюмов ◽  
П.А. Сломинский ◽  
...  

Несмотря на очевидный прогресс, достигнутый в изучении молекулярно-генетических факторов и механизмов патогенеза болезни Паркинсона (БП), в настоящее время стало ясно, что нарушения в структуре ДНК не описывают весь спектр патологических изменений, наблюдаемых при развитии заболевания. В настоящее время показано, что существенное влияние на патогенез БП могут оказывать изменения на уровне транскриптома. В работе были использованы мышиные модели досимптомной стадии БП, поздней досимптомной и ранней симптомной (РСС) стадиями БП. Для полнотранскриптомного анализа пулов РНК тканей черной субстанции и стриатума мозга мышей использовались микрочипы MouseRef-8 v2.0 Expression BeadChip Kit («Illumina», США). Полученные данные указывают на последовательное вовлечение транскриптома в патогенез БП, а также на то, что изменения на транскриптомном уровне процессов транспорта и митохондриального биогенеза могут играть важную роль в нейродегенерации при БП уже на самых ранних этапах. Parkinson’s disease (PD) is a complex systemic disease, mainly associated with the death of dopaminergic neurons. Despite the obvious progress made in the study of molecular genetic factors and mechanisms of PD pathogenesis, it has now become clear that violations in the DNA structure do not describe the entire spectrum of pathological changes observed during the development of the disease. It has now been shown that changes at the transcriptome level can have a significant effect on the pathogenesis of PD. The authors used models of the presymptomatic stage of PD with mice decapitation after 6 hours (6 h-PSS), presymptomatic stage with decapitation after 24 hours (24 h-PSS), advanced presymptomatic (Adv-PSS) and early symptomatic (ESS) stages of PD. For whole transcriptome analysis of RNA pools of the substantia nigra and mouse striatum, the MouseRef-8 v2.0 Expression BeadChip Kit microchips (Illumina, USA) were used. As a result of the analysis of whole transcriptome data, it was shown that, there are a greater number of statistically significant changes in the tissues of the brain and peripheral blood of mice with Adv-PSS and ESS models of PD compared to 6 h-PSS and 24 h-PSS models. In general, the obtained data indicate the sequential involvement of the transcriptome in the pathogenesis of PD, as well as the fact that changes at the transcriptome level of the processes of transport and mitochondrial biogenesis can play an important role in neurodegeneration in PD at an early stage.


Author(s):  
Sally M. Essawy ◽  
Basil Kamel ◽  
Mohamed S. Elsawy

Some buildings hold certain qualities of space design similar to those originated from nature in harmony with its surroundings. These buildings, mostly associated with religious beliefs and practices, allow for human comfort and a unique state of mind. This paper aims to verify such effect on the human brain. It concentrates on measuring brain waves when the user is located in several spots (coordinates) in some of these buildings. Several experiments are conducted on selected case studies to identify whether certain buildings affect the brain wave frequencies of their users or not. These are measured in terms of Brain Wave Frequency Charts through EEG Device. The changes identified on the brain were then translated into a brain diagram that reflects the spiritual experience all through the trip inside the selected buildings. This could then be used in architecture to enhance such unique quality.


Author(s):  
Henrik Hogh-Olesen

Chapter 7 takes the investigation of the aesthetic impulse into the human brain to understand, first, why only we—and not our closest relatives among the primates—express ourselves aesthetically; and second, how the brain reacts when presented with aesthetic material. Brain scans are less useful when you are interested in the Why of aesthetic behavior rather than the How. Nevertheless, some brain studies have been ground-breaking, and neuroaesthetics offers a pivotal argument for the key function of the aesthetic impulse in human lives; it shows us that the brain’s reward circuit is activated when we are presented with aesthetic objects and stimuli. For why reward a perception or an activity that is evolutionarily useless and worthless in relation to human existence?


2021 ◽  
Vol 16 ◽  
pp. 263310552110187
Author(s):  
Christopher D Link

Numerous studies have identified microbial sequences or epitopes in pathological and non-pathological human brain samples. It has not been resolved if these observations are artifactual, or truly represent population of the brain by microbes. Given the tempting speculation that resident microbes could play a role in the many neuropsychiatric and neurodegenerative diseases that currently lack clear etiologies, there is a strong motivation to determine the “ground truth” of microbial existence in living brains. Here I argue that the evidence for the presence of microbes in diseased brains is quite strong, but a compelling demonstration of resident microbes in the healthy human brain remains to be done. Dedicated animal models studies may be required to determine if there is indeed a “brain microbiome.”


Animals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 973
Author(s):  
Thomas R. Zentall

The humane treatment of animals suggests that they should be housed in an environment that is rich in stimulation and allows for varied activities. However, even if one’s main concern is an accurate assessment of their learning and cognitive abilities, housing them in an enriched environment can have an important effect on the assessment of those abilities. Research has found that the development of the brain of animals is significantly affected by the environment in which they live. Not surprisingly, their ability to learn both simple and complex tasks is affected by even modest time spent in an enriched environment. In particular, animals that are housed in an enriched environment are less impulsive and make more optimal choices than animals housed in isolation. Even the way that they judge the passage of time is affected by their housing conditions. Some researchers have even suggested that exposing animals to an enriched environment can make them more “optimistic” in how they treat ambiguous stimuli. Whether that behavioral effect reflects the subtlety of differences in optimism/pessimism or something simpler, like differences in motivation, incentive, discriminability, or neophobia, it is clear that the conditions of housing can have an important effect on the learning and cognition of animals.


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