Search results: Found 4

Listing 1 - 4 of 4
Sort by
Lateralization and cognitive systems

Authors: --- --- ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889194117 Year: Pages: 314 DOI: 10.3389/978-2-88919-411-7 Language: English
Publisher: Frontiers Media SA
Subject: Psychology --- Science (General)
Added to DOAB on : 2015-12-10 11:59:06
License:

Loading...
Export citation

Choose an application

Abstract

Left-right asymmetries of structure and function are a common organization principle in the brains of humans and non-human vertebrates alike. While there are inherently asymmetric systems such as the human language system or the song system of songbirds, the impact of structural or functional asymmetries on perception, cognition and behavior is not necessarily limited to these systems. For example, performance in experimental paradigms that assess executive functions such as inhibition, planning or action monitoring is influenced by information processing in the bottom-up channel. Depending on the type of stimuli used, one hemisphere can be more efficient in processing than the other and these functional cerebral asymmetries have been shown to modulate the efficacy of executive functions via the bottom-up channel. We only begin to understand the complex neuronal mechanisms underlying this interaction between hemispheric asymmetries and cognitive systems. Therefore, it is the aim of this Research Topics to further elucidate how structural or functional hemispheric asymmetries modulate perception, cognition and behavior in the broadest sense.

From Sex Differences in Neuroscience to a Neuroscience of Sex Differences: New Directions and Perspectives

Author:
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889196890 Year: Pages: 199 DOI: 10.3389/978-2-88919-689-0 Language: English
Publisher: Frontiers Media SA
Subject: Internal medicine --- Medicine (General) --- Neurology --- Science (General)
Added to DOAB on : 2016-04-07 11:22:02
License:

Loading...
Export citation

Choose an application

Abstract

This research topic aims to integrate scattered findings on sex differences in neuroscience into a broader theory of how the human brain is shaped by sex and sex hormones in order to cause the great variety of sex differences that are commonly observed. It can be assumed that these differences didn’t occur arbitrarily, but that they rather determined and still determine evolutionary success of individuals and were shaped by the processes of natural and in particular sexual selection. Therefore, sex differences are not negligible and sex difference research cannot be discriminating against one sex or the other. In fact a better understanding of the underlying causes of sex differences has great advantages for both men and women and society as a whole, not only in terms of health care, but in every aspect of life. Gender equality can only work out if it is equally well understood for men and women what their individual resources and needs are. Therefore, it is of great importance to pave the way for identifying the underlying principles of structural and functional brain organization that cause men and women to act, think and feel differently. To this end it is of particular interest to identify possible similarities and interrelations between sex differences that did so far stand separately, in order to investigate whether they share a common source. To understand, where a specific sex difference comes from and whether or not it is caused by the same principle as other sex differences, it is necessary to explicitly link sex differences in behavior to their neuronal correlates and vice versa link sex differences in brain structure and function to their behavioral outcomes. In particular a new understanding of male and female brain functioning may arise from findings on how sex hormones interact with various neurotransmitter systems. In the past few years several findings demonstrated that women’s behavior is influenced by the sex hormone fluctuations they experience naturally during their menstrual cycle to the extent that sex differences may only be detectable in one cycle phase but not another. The study of menstrual cycle dependent effects gives important hints about which sex differences are activational and which are organizational. Additionally it only recently came to attention, that hormonal contraception may alter a women’s mood, cognition and behavior as a consequence of changes in brain structure and function. The underlying mechanisms are so poorly understood that it is even hard to predict, whether hormonal contraception will mask or amplify sex differences in a given task. Since the oral hormonal contraceptive pill is meanwhile used by 100 million women worldwide and even by teenagers whose brains are not yet fully developed, the question of how the synthetic steroids contained in hormonal contraceptives act on the brain is to be studied hand in hand with naturally occurring sex differences. This topic summarizes the current state of the art in sex difference research and gives new perspectives in terms of hypothesis generation an methodology. Both are necessary to gain a complete picture of what it is that makes a brain male or female and move towards a neuroscience of sex differences.

The causes and consequences of microbial community structure

Authors: --- ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889193615 Year: Pages: 184 DOI: 10.3389/978-2-88919-361-5 Language: English
Publisher: Frontiers Media SA
Subject: Microbiology --- Science (General)
Added to DOAB on : 2015-11-19 16:29:12
License:

Loading...
Export citation

Choose an application

Abstract

The causes and consequences of differences in microbial community structure, defined here as the relative proportions of rare and abundant organisms within a community, are poorly understood. Articles in "The Causes and Consequences of Microbial Community Structure", use empirical or modeling approaches as well as literature reviews to enrich our mechanistic understanding of the controls over the relationship between community structure and ecosystem processes. Specifically, authors address the role of trait distributions and tradeoffs, species-species interactions, evolutionary dynamics, community assembly processes and physical controls in affecting ‘who’s there’ and ‘what they are doing’.

Paradigm changes are required in HIV vaccine research

Author:
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889197279 Year: Pages: 74 DOI: 10.3389/978-2-88919-727-9 Language: English
Publisher: Frontiers Media SA
Subject: Allergy and Immunology --- Medicine (General)
Added to DOAB on : 2016-04-07 11:22:02
License:

Loading...
Export citation

Choose an application

Abstract

In his 1962 book "The Structure of Scientific Revolutions", Thomas Kuhn famously argued that researchers in every field of scientific enquiry always operate under a set of presuppositions known as paradigms that are rarely explicitly stated. In the field of HIV vaccine research, several prevailing paradigms led scientists for many years to pursue unfruitful lines of investigations that impeded significant progress. The uncritical acceptance of reigning paradigms makes scientists reluctant to abandon their mistaken assumptions even when they obtain results that are not consistent with the paradigms. The following five paradigms which disregard the degeneracy of the immune system were particularly harmful. 1) There is a primary and intrinsic epitope specific for each B cell receptor and for the corresponding monoclonal antibody.In reality, there is no single, intrinsic or "real" epitope for any antibody but only a diverse group of potential ligands. 2) Reactions with monoclonal antibodies are more specific than the combined reactivity of polyclonal antibodies. In reality, a polyclonal antiserum has greater specificity for a multiepitopic protein because different antibodies in the antiserum recognize separate epitopes on the same protein, giving rise to an additive specificity effect. By focusing vaccine design on single epitope-Mab pairs, the beneficial neutralizing synergy that occurs with polyclonal antibody responses is overlooked. 3) The HIV epitope identified by solving the crystallographic structure of a broadly neutralizing Mab – HIV Env complex should be able, when used as immunogen, to elicit antibodies endowed with the same neutralizing capacity as the Mab. Since every anti HIV bnMab is polyspecific, the single epitope identified in the complex is not necessarily the one that elicited the bnMab. Since hypermutated Mabs used in crystallographic studies differ from their germline-like receptor version present before somatic hypermutation, the identified epitope will not be an effective vaccine immunogen. 4) Effective vaccine immunogenicity can be predicted from the antigenic binding capacity of viral epitopes. Most fragments of a viral antigen can induce antibodies that react with the immunogen, but this is irrelevant for vaccination since these antibodies rarely recognize the cognate, intact antigen and even more rarely neutralize the infectivity of the viral pathogen that harbors the antigen. 5) The rational design of vaccine immunogens using reverse vaccinology is superior to the trial-and-error screening of vaccine candidates able to induce protective immunity. One epitope can be designed to increase its structural complementarity to one particular bnMab, but such antigen design is only masquerading as immunogen design because it is assumed that antigenic reactivity necessarily entails the immunogenic capacity to elicit neutralizing antibodies. When HIV Env epitopes, engineered to react with a bnMab are used to select from human donors rare memory B cells secreting bnAbs, this represents antigen design and not immunogen design. The aim of this Research Topic is to replace previous misleading paradigms by novel ones that better fit our current understanding of immunological specificity and will help HIV vaccine development.

Listing 1 - 4 of 4
Sort by
Narrow your search

Publisher

Frontiers Media SA (4)


License

CC by (4)


Language

english (4)


Year
From To Submit

2015 (4)