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Sample records for adult brain size

  1. Prenatal Exposure to Autism-Specific Maternal Autoantibodies Alters Proliferation of Cortical Neural Precursor Cells, Enlarges Brain, and Increases Neuronal Size in Adult Animals.

    PubMed

    Martínez-Cerdeño, Verónica; Camacho, Jasmin; Fox, Elizabeth; Miller, Elaine; Ariza, Jeanelle; Kienzle, Devon; Plank, Kaela; Noctor, Stephen C; Van de Water, Judy

    2016-01-01

    Autism spectrum disorders (ASDs) affect up to 1 in 68 children. Autism-specific autoantibodies directed against fetal brain proteins have been found exclusively in a subpopulation of mothers whose children were diagnosed with ASD or maternal autoantibody-related autism. We tested the impact of autoantibodies on brain development in mice by transferring human antigen-specific IgG directly into the cerebral ventricles of embryonic mice during cortical neurogenesis. We show that autoantibodies recognize radial glial cells during development. We also show that prenatal exposure to autism-specific maternal autoantibodies increased stem cell proliferation in the subventricular zone (SVZ) of the embryonic neocortex, increased adult brain size and weight, and increased the size of adult cortical neurons. We propose that prenatal exposure to autism-specific maternal autoantibodies directly affects radial glial cell development and presents a viable pathologic mechanism for the maternal autoantibody-related prenatal ASD risk factor.

  2. Aging, Brain Size, and IQ.

    ERIC Educational Resources Information Center

    Bigler, Erin D.; And Others

    1995-01-01

    Whether cross-sectional rates of decline for brain volume and the Performance Intellectual Quotient of the Wechsler Adult Intelligence Scale-Revised were equivalent over the years 16 to 65 was studied with 196 volunteers. Results indicate remarkably similar rates of decline in perceptual-motor functions and aging brain volume loss. (SLD)

  3. Brain and Spinal Cord Tumors in Adults

    MedlinePlus

    ... saved articles window. My Saved Articles » My ACS » Brain and Spinal Cord Tumors in Adults Download Printable ... the topics below to get started. What Is Brain/CNS Tumors In Adults? What are adult brain ...

  4. Cytoskeletal genes regulating brain size.

    PubMed

    Bond, Jacquelyn; Woods, C Geoffrey

    2006-02-01

    One of the most notable trends in human evolution is the dramatic increase in brain size that has occurred in the great ape clade, culminating in humans. Of particular interest is the vast expanse of the cerebral cortex, which is believed to have resulted in our ability to perform higher cognitive functions. Recent investigations of congenital microcephaly in humans have resulted in the identification of several genes that non-redundantly and specifically influence mammalian brain size. These genes appear to affect neural progenitor cell number through microtubular organisation at the centrosome. PMID:16337370

  5. Brain tumor - primary - adults

    MedlinePlus

    ... tumor, relieve symptoms, and improve brain function or comfort. Surgery is often needed for most primary brain ... and pressure Anticonvulsants to reduce seizures Pain medicines Comfort measures, safety measures, physical therapy, and occupational therapy ...

  6. Brain size varies with temperature in vertebrates.

    PubMed

    Gillooly, James F; McCoy, Michael W

    2014-01-01

    The tremendous variation in brain size among vertebrates has long been thought to be related to differences in species' metabolic rates. It is thought that species with higher metabolic rates can supply more energy to support the relatively high cost of brain tissue. And yet, while body temperature is known to be a major determinant of metabolic rate, the possible effects of temperature on brain size have scarcely been explored. Thus, here we explore the effects of temperature on brain size among diverse vertebrates (fishes, amphibians, reptiles, birds and mammals). We find that, after controlling for body size, brain size increases exponentially with temperature in much the same way as metabolic rate. These results suggest that temperature-dependent changes in aerobic capacity, which have long been known to affect physical performance, similarly affect brain size. The observed temperature-dependence of brain size may explain observed gradients in brain size among both ectotherms and endotherms across broad spatial and temporal scales.

  7. Scaling brain size, keeping timing: evolutionary preservation of brain rhythms.

    PubMed

    Buzsáki, György; Logothetis, Nikos; Singer, Wolf

    2013-10-30

    Despite the several-thousand-fold increase of brain volume during the course of mammalian evolution, the hierarchy of brain oscillations remains remarkably preserved, allowing for multiple-time-scale communication within and across neuronal networks at approximately the same speed, irrespective of brain size. Deployment of large-diameter axons of long-range neurons could be a key factor in the preserved time management in growing brains. We discuss the consequences of such preserved network constellation in mental disease, drug discovery, and interventional therapies.

  8. Scaling Brain Size, Keeping Timing: Evolutionary Preservation of Brain Rhythms

    PubMed Central

    Buzsáki, György; Logothetis, Nikos; Singer, Wolf

    2014-01-01

    Despite the several-thousand-fold increase of brain volume during the course of mammalian evolution, the hierarchy of brain oscillations remains remarkably preserved, allowing for multiple-time-scale communication within and across neuronal networks at approximately the same speed, irrespective of brain size. Deployment of large-diameter axons of long-range neurons could be a key factor in the preserved time management in growing brains. We discuss the consequences of such preserved network constellation in mental disease, drug discovery, and interventional therapies. PMID:24183025

  9. Sexual selection on brain size in shorebirds (Charadriiformes).

    PubMed

    García-Peña, G E; Sol, D; Iwaniuk, A N; Székely, T

    2013-04-01

    Natural selection is considered a major force shaping brain size evolution in vertebrates, whereas the influence of sexual selection remains controversial. On one hand, sexual selection could promote brain enlargement by enhancing cognitive skills needed to compete for mates. On the other hand, sexual selection could favour brain size reduction due to trade-offs between investing in brain tissue and in sexually selected traits. These opposed predictions are mirrored in contradictory relationships between sexual selection proxies and brain size relative to body size. Here, we report a phylogenetic comparative analysis that highlights potential flaws in interpreting relative brain size-mating system associations as effects of sexual selection on brain size in shorebirds (Charadriiformes), a taxonomic group with an outstanding diversity in breeding systems. Considering many ecological effects, relative brain size was not significantly correlated with testis size. In polyandrous species, however, relative brain sizes of males and females were smaller than in monogamous species, and females had smaller brain size than males. Although these findings are consistent with sexual selection reducing brain size, they could also be due to females deserting parental care, which is a common feature of polyandrous species. Furthermore, our analyses suggested that body size evolved faster than brain size, and thus the evolution of body size may be confounding the effect of the mating system on relative brain size. The brain size-mating system association in shorebirds is thus not only due to sexual selection on brain size but rather, to body size evolution and other multiple simultaneous effects.

  10. A brain sexual dimorphism controlled by adult circulating androgens.

    PubMed

    Cooke, B M; Tabibnia, G; Breedlove, S M

    1999-06-22

    Reports of structural differences between the brains of men and women, heterosexual and homosexual men, and male-to-female transsexuals and other men have been offered as evidence that the behavioral differences between these groups are likely caused by differences in the early development of the brain. However, a possible confounding variable is the concentration of circulating hormones seen in these groups in adulthood. Evaluation of this possibility hinges on the extent to which circulating hormones can alter the size of mammalian brain regions as revealed by Nissl stains. We now report a sexual dimorphism in the volume of a brain nucleus in rats that can be completely accounted for by adult sex differences in circulating androgen. The posterodorsal nucleus of the medial amygdala (MePD) has a greater volume in male rats than in females, but adult castration of males causes the volume to shrink to female values within four weeks, whereas androgen treatment of adult females for that period enlarges the MePD to levels equivalent to normal males. This report demonstrates that adult hormone manipulations can completely reverse a sexual dimorphism in brain regional volume in a mammalian species. The sex difference and androgen responsiveness of MePD volume is reflected in the soma size of neurons there. PMID:10377450

  11. Molecular genetic determinants of human brain size.

    PubMed

    Tang, Bor Luen

    2006-07-01

    Cognitive skills such as tool use, syntactical languages, and self-awareness differentiate humans from other primates. The underlying basis for this cognitive difference has been widely associated with a high encephalization quotient and an anatomically distinct, exceptionally large cerebral cortex. Investigations on congenital microcephaly had revealed several genes that affect mammalian brain size when mutated. At least four of these, microcephalin (MCPH1), abnormal spindle-like microcephaly-associated (ASPM), cyclin-dependent kinase 5 regulatory associated protein 2 (CDK5RAP2), and centromere-associated protein J (CENPJ) are known to have undergone significant positive selection in the great apes and human lineages during primate evolution. MCPH1 and ASPM both have very young single nucleotide polymorphism haplotypes associated with modern humans, and these genes are presumably still evolving in Homo sapiens. Microcephalin has a role in DNA damage response and regulation of cell cycle checkpoints. The other known microcephaly-associated genes encode microtubule-associated centrosomal proteins that might regulate neural progenitor cell division and cell number. Recent reports have also unveiled a previously unknown function of ephrins and Eph in the regulation of neural progenitor cell death with a consequential effect on brain size. Understanding the mechanism for developmental control of brain organogenesis by these genes, and others such as FOXP2, shall provide fresh perspectives on the evolution of human intelligence. PMID:16716254

  12. Molecular genetic determinants of human brain size.

    PubMed

    Tang, Bor Luen

    2006-07-01

    Cognitive skills such as tool use, syntactical languages, and self-awareness differentiate humans from other primates. The underlying basis for this cognitive difference has been widely associated with a high encephalization quotient and an anatomically distinct, exceptionally large cerebral cortex. Investigations on congenital microcephaly had revealed several genes that affect mammalian brain size when mutated. At least four of these, microcephalin (MCPH1), abnormal spindle-like microcephaly-associated (ASPM), cyclin-dependent kinase 5 regulatory associated protein 2 (CDK5RAP2), and centromere-associated protein J (CENPJ) are known to have undergone significant positive selection in the great apes and human lineages during primate evolution. MCPH1 and ASPM both have very young single nucleotide polymorphism haplotypes associated with modern humans, and these genes are presumably still evolving in Homo sapiens. Microcephalin has a role in DNA damage response and regulation of cell cycle checkpoints. The other known microcephaly-associated genes encode microtubule-associated centrosomal proteins that might regulate neural progenitor cell division and cell number. Recent reports have also unveiled a previously unknown function of ephrins and Eph in the regulation of neural progenitor cell death with a consequential effect on brain size. Understanding the mechanism for developmental control of brain organogenesis by these genes, and others such as FOXP2, shall provide fresh perspectives on the evolution of human intelligence.

  13. Female brain size and parental care in carnivores.

    PubMed Central

    Gittleman, J L

    1994-01-01

    Comparative studies indicate that species differences in mammalian brain size relate to body size, ecology, and life-history traits. Previous analyses failed to show intrasexual or behavioral patterns of brain size in mammals. Across the terrestrial Carnivora, I find to the contrary. Differences in female, but not male, brain size associate with a fundamental ecological and evolutionary characteristic of female behavior. Other factors equal, females that provide the sole parental care have larger brains than those of biparental or communal species. For females, more parental investment accompanies larger brains. Future comparative studies of mammalian brain size must recognize that some patterns arise independently in the two sexes. PMID:8202515

  14. Reassessing the relationship between brain size, life history, and metabolism at the marsupial/placental dichotomy.

    PubMed

    Weisbecker, Vera; Goswami, Anjali

    2014-09-01

    A vigorous discussion surrounds the question as to what enables some mammals--including primates and cetaceans--to evolve large brains. We recently published a study suggesting that the radiation of marsupial mammals is highly relevant to this question because of the unique reproductive and metabolic traits within this clade. In particular, we controversially suggested that marsupial brain sizes are not systematically smaller than those of placentals, and that elevated basal metabolic rates (BMR) are not linked to larger marsupial brains. As our dataset was found to contain some erroneous body size data, derived from a published source, we here use an updated and corrected dataset and employ standard as well as phylogenetically corrected analyses to re-assess and elaborate on our original conclusions. Our proposal that marsupials are not systematically smaller-brained than placentals remains supported, particularly when the unusually large-brained placental clade, Primates, is excluded. Use of the new dataset not only confirms that high metabolic rates are not associated with larger brain size in marsupials, but we additionally find some support for a striking negative correlation between BMR and brain size. The best supported correlates of large brain size remain the reproductive traits of weaning age and litter size. These results support our suggestion that mammalian brain sizes (including, by inference, those of monotremes) are predominantly constrained by the ability of females to fuel the growth of their offspring's large brains, rather than by the maintenance requirements of the adult brain. PMID:25186933

  15. The Evolution of Human Intelligence and the Coefficient of Additive Genetic Variance in Human Brain Size

    ERIC Educational Resources Information Center

    Miller, Geoffrey F.; Penke, Lars

    2007-01-01

    Most theories of human mental evolution assume that selection favored higher intelligence and larger brains, which should have reduced genetic variance in both. However, adult human intelligence remains highly heritable, and is genetically correlated with brain size. This conflict might be resolved by estimating the coefficient of additive genetic…

  16. Treatment of primary brain tumours in adults.

    PubMed

    McNamara, Shanne

    This article considers the complexities of caring for patients with primary brain tumours. The incidence, classification and clinical signs and symptoms are outlined. Adult patients experience disabling effects as a result of a brain tumour, which is often accompanied by high morbidity and mortality rates. The various treatment options available are summarised. However, for many patients, there are limited curative treatment options and the main focus is palliative care. The nurse's contribution to care and support of these patients and their families is discussed, with the aim of improving their quality of life.

  17. Positive genetic correlation between brain size and sexual traits in male guppies artificially selected for brain size.

    PubMed

    Kotrschal, A; Corral-Lopez, A; Zajitschek, S; Immler, S; Maklakov, A A; Kolm, N

    2015-04-01

    Brain size is an energetically costly trait to develop and maintain. Investments into other costly aspects of an organism's biology may therefore place important constraints on brain size evolution. Sexual traits are often costly and could therefore be traded off against neural investment. However, brain size may itself be under sexual selection through mate choice on cognitive ability. Here, we use guppy (Poecilia reticulata) lines selected for large and small brain size relative to body size to investigate the relationship between brain size, a large suite of male primary and secondary sexual traits, and body condition index. We found no evidence for trade-offs between brain size and sexual traits. Instead, larger-brained males had higher expression of several primary and precopulatory sexual traits--they had longer genitalia, were more colourful and developed longer tails than smaller-brained males. Larger-brained males were also in better body condition when housed in single-sex groups. There was no difference in post-copulatory sexual traits between males from the large- and small-brained lines. Our data do not support the hypothesis that investment into sexual traits is an important limiting factor to brain size evolution, but instead suggest that brain size and several sexual traits are positively genetically correlated. PMID:25705852

  18. Positive genetic correlation between brain size and sexual traits in male guppies artificially selected for brain size.

    PubMed

    Kotrschal, A; Corral-Lopez, A; Zajitschek, S; Immler, S; Maklakov, A A; Kolm, N

    2015-04-01

    Brain size is an energetically costly trait to develop and maintain. Investments into other costly aspects of an organism's biology may therefore place important constraints on brain size evolution. Sexual traits are often costly and could therefore be traded off against neural investment. However, brain size may itself be under sexual selection through mate choice on cognitive ability. Here, we use guppy (Poecilia reticulata) lines selected for large and small brain size relative to body size to investigate the relationship between brain size, a large suite of male primary and secondary sexual traits, and body condition index. We found no evidence for trade-offs between brain size and sexual traits. Instead, larger-brained males had higher expression of several primary and precopulatory sexual traits--they had longer genitalia, were more colourful and developed longer tails than smaller-brained males. Larger-brained males were also in better body condition when housed in single-sex groups. There was no difference in post-copulatory sexual traits between males from the large- and small-brained lines. Our data do not support the hypothesis that investment into sexual traits is an important limiting factor to brain size evolution, but instead suggest that brain size and several sexual traits are positively genetically correlated.

  19. Extracellular proteolysis in the adult murine brain.

    PubMed

    Sappino, A P; Madani, R; Huarte, J; Belin, D; Kiss, J Z; Wohlwend, A; Vassalli, J D

    1993-08-01

    Plasminogen activators are important mediators of extracellular metabolism. In the nervous system, plasminogen activators are thought to be involved in the remodeling events required for cell migration during development and regeneration. We have now explored the expression of the plasminogen activator/plasmin system in the adult murine central nervous system. Tissue-type plasminogen activator is synthesized by neurons of most brain regions, while prominent tissue-type plasminogen activator-catalyzed proteolysis is restricted to discrete areas, in particular within the hippocampus and hypothalamus. Our observations indicate that tissue-type plasminogen activator-catalyzed proteolysis in neural tissues is not limited to ontogeny, but may also contribute to adult central nervous system physiology, for instance by influencing neuronal plasticity and synaptic reorganization. The identification of an extracellular proteolytic system active in the adult central nervous system may also help gain insights into the pathogeny of neurodegenerative disorders associated with extracellular protein deposition.

  20. Adaptive evolution of four microcephaly genes and the evolution of brain size in anthropoid primates.

    PubMed

    Montgomery, Stephen H; Capellini, Isabella; Venditti, Chris; Barton, Robert A; Mundy, Nicholas I

    2011-01-01

    The anatomical basis and adaptive function of the expansion in primate brain size have long been studied; however, we are only beginning to understand the genetic basis of these evolutionary changes. Genes linked to human primary microcephaly have received much attention as they have accelerated evolutionary rates along lineages leading to humans. However, these studies focus narrowly on apes, and the link between microcephaly gene evolution and brain evolution is disputed. We analyzed the molecular evolution of four genes associated with microcephaly (ASPM, CDK5RAP2, CENPJ, MCPH1) across 21 species representing all major clades of anthropoid primates. Contrary to prevailing assumptions, positive selection was not limited to or intensified along the lineage leading to humans. In fact we show that all four loci were subject to positive selection across the anthropoid primate phylogeny. We developed clearly defined hypotheses to explicitly test if selection on these loci was associated with the evolution of brain size. We found positive relationships between both CDK5RAP2 and ASPM and neonatal brain mass and somewhat weaker relationships between these genes and adult brain size. In contrast, there is no evidence linking CENPJ and MCPH1 to brain size evolution. The stronger association of ASPM and CDK5RAP2 evolution with neonatal brain size than with adult brain size is consistent with these loci having a direct effect on prenatal neuronal proliferation. These results suggest that primate brain size may have at least a partially conserved genetic basis. Our results contradict a previous study that linked adaptive evolution of ASPM to changes in relative cortex size; however, our analysis indicates that this conclusion is not robust. Our finding that the coding regions of two widely expressed loci has experienced pervasive positive selection in relation to a complex, quantitative developmental phenotype provides a notable counterexample to the commonly asserted

  1. Evolutionary ecology of intraspecific brain size variation: a review.

    PubMed

    Gonda, Abigél; Herczeg, Gábor; Merilä, Juha

    2013-08-01

    The brain is a trait of central importance for organismal performance and fitness. To date, evolutionary studies of brain size variation have mainly utilized comparative methods applied at the level of species or higher taxa. However, these studies suffer from the difficulty of separating causality from correlation. In the other extreme, studies of brain plasticity have focused mainly on within-population patterns. Between these extremes lie interpopulational studies, focusing on brain size variation among populations of the same species that occupy different habitats or selective regimes. These studies form a rapidly growing field of investigations which can help us to understand brain evolution by providing a test bed for ideas born out of interspecific studies, as well as aid in uncovering the relative importance of genetic and environmental factors shaping variation in brain size and architecture. Aside from providing the first in depth review of published intraspecific studies of brain size variation, we discuss the prospects embedded with interpopulational studies of brain size variation. In particular, the following topics are identified as deserving further attention: (i) studies focusing on disentangling the contributions of genes, environment, and their interactions on brain variation within and among populations, (ii) studies applying quantitative genetic tools to evaluate the relative importance of genetic and environmental factors on brain features at different ontogenetic stages, (iii) apart from utilizing simple gross estimates of brain size, future studies could benefit from use of neuroanatomical, neurohistological, and/or molecular methods in characterizing variation in brain size and architecture. Evolution of brain size and architecture is a widely studied topic. However, the majority of studies are interspecific and comparative. Here we summarize the recently growing body of intraspecific studies based on population comparisons and outline the

  2. Evolutionary ecology of intraspecific brain size variation: a review

    PubMed Central

    Gonda, Abigél; Herczeg, Gábor; Merilä, Juha

    2013-01-01

    Abstract The brain is a trait of central importance for organismal performance and fitness. To date, evolutionary studies of brain size variation have mainly utilized comparative methods applied at the level of species or higher taxa. However, these studies suffer from the difficulty of separating causality from correlation. In the other extreme, studies of brain plasticity have focused mainly on within-population patterns. Between these extremes lie interpopulational studies, focusing on brain size variation among populations of the same species that occupy different habitats or selective regimes. These studies form a rapidly growing field of investigations which can help us to understand brain evolution by providing a test bed for ideas born out of interspecific studies, as well as aid in uncovering the relative importance of genetic and environmental factors shaping variation in brain size and architecture. Aside from providing the first in depth review of published intraspecific studies of brain size variation, we discuss the prospects embedded with interpopulational studies of brain size variation. In particular, the following topics are identified as deserving further attention: (i) studies focusing on disentangling the contributions of genes, environment, and their interactions on brain variation within and among populations, (ii) studies applying quantitative genetic tools to evaluate the relative importance of genetic and environmental factors on brain features at different ontogenetic stages, (iii) apart from utilizing simple gross estimates of brain size, future studies could benefit from use of neuroanatomical, neurohistological, and/or molecular methods in characterizing variation in brain size and architecture. Evolution of brain size and architecture is a widely studied topic. However, the majority of studies are interspecific and comparative. Here we summarize the recently growing body of intraspecific studies based on population comparisons and

  3. Larger brain size indirectly increases vulnerability to extinction in mammals.

    PubMed

    Gonzalez-Voyer, Alejandro; González-Suárez, Manuela; Vilà, Carles; Revilla, Eloy

    2016-06-01

    Although previous studies have addressed the question of why large brains evolved, we have limited understanding of potential beneficial or detrimental effects of enlarged brain size in the face of current threats. Using novel phylogenetic path analysis, we evaluated how brain size directly and indirectly, via its effects on life history and ecology, influences vulnerability to extinction across 474 mammalian species. We found that larger brains, controlling for body size, indirectly increase vulnerability to extinction by extending the gestation period, increasing weaning age, and limiting litter sizes. However, we found no evidence of direct, beneficial, or detrimental effects of brain size on vulnerability to extinction, even when we explicitly considered the different types of threats that lead to vulnerability. Order-specific analyses revealed qualitatively similar patterns for Carnivora and Artiodactyla. Interestingly, for Primates, we found that larger brain size was directly (and indirectly) associated with increased vulnerability to extinction. Our results indicate that under current conditions, the constraints on life history imposed by large brains outweigh the potential benefits, undermining the resilience of the studied mammals. Contrary to the selective forces that have favored increased brain size throughout evolutionary history, at present, larger brains have become a burden for mammals. PMID:27159368

  4. Larger brain size indirectly increases vulnerability to extinction in mammals.

    PubMed

    Gonzalez-Voyer, Alejandro; González-Suárez, Manuela; Vilà, Carles; Revilla, Eloy

    2016-06-01

    Although previous studies have addressed the question of why large brains evolved, we have limited understanding of potential beneficial or detrimental effects of enlarged brain size in the face of current threats. Using novel phylogenetic path analysis, we evaluated how brain size directly and indirectly, via its effects on life history and ecology, influences vulnerability to extinction across 474 mammalian species. We found that larger brains, controlling for body size, indirectly increase vulnerability to extinction by extending the gestation period, increasing weaning age, and limiting litter sizes. However, we found no evidence of direct, beneficial, or detrimental effects of brain size on vulnerability to extinction, even when we explicitly considered the different types of threats that lead to vulnerability. Order-specific analyses revealed qualitatively similar patterns for Carnivora and Artiodactyla. Interestingly, for Primates, we found that larger brain size was directly (and indirectly) associated with increased vulnerability to extinction. Our results indicate that under current conditions, the constraints on life history imposed by large brains outweigh the potential benefits, undermining the resilience of the studied mammals. Contrary to the selective forces that have favored increased brain size throughout evolutionary history, at present, larger brains have become a burden for mammals.

  5. Construction of brain atlases based on a multi-center MRI dataset of 2020 Chinese adults.

    PubMed

    Liang, Peipeng; Shi, Lin; Chen, Nan; Luo, Yishan; Wang, Xing; Liu, Kai; Mok, Vincent C T; Chu, Winnie C W; Wang, Defeng; Li, Kuncheng

    2015-01-01

    Despite the known morphological differences (e.g., brain shape and size) in the brains of populations of different origins (e.g., age and race), the Chinese brain atlas is less studied. In the current study, we developed a statistical brain atlas based on a multi-center high quality magnetic resonance imaging (MRI) dataset of 2020 Chinese adults (18-76 years old). We constructed 12 Chinese brain atlas from the age 20 year to the age 75 at a 5 years interval. New Chinese brain standard space, coordinates, and brain area labels were further defined. The new Chinese brain atlas was validated in brain registration and segmentation. It was found that, as contrast to the MNI152 template, the proposed Chinese atlas showed higher accuracy in hippocampus segmentation and relatively smaller shape deformations during registration. These results indicate that a population-specific time varying brain atlas may be more appropriate for studies involving Chinese populations. PMID:26678304

  6. Brain size predicts problem-solving ability in mammalian carnivores

    PubMed Central

    Benson-Amram, Sarah; Dantzer, Ben; Stricker, Gregory; Swanson, Eli M.; Holekamp, Kay E.

    2016-01-01

    Despite considerable interest in the forces shaping the relationship between brain size and cognitive abilities, it remains controversial whether larger-brained animals are, indeed, better problem-solvers. Recently, several comparative studies have revealed correlations between brain size and traits thought to require advanced cognitive abilities, such as innovation, behavioral flexibility, invasion success, and self-control. However, the general assumption that animals with larger brains have superior cognitive abilities has been heavily criticized, primarily because of the lack of experimental support for it. Here, we designed an experiment to inquire whether specific neuroanatomical or socioecological measures predict success at solving a novel technical problem among species in the mammalian order Carnivora. We presented puzzle boxes, baited with food and scaled to accommodate body size, to members of 39 carnivore species from nine families housed in multiple North American zoos. We found that species with larger brains relative to their body mass were more successful at opening the boxes. In a subset of species, we also used virtual brain endocasts to measure volumes of four gross brain regions and show that some of these regions improve model prediction of success at opening the boxes when included with total brain size and body mass. Socioecological variables, including measures of social complexity and manual dexterity, failed to predict success at opening the boxes. Our results, thus, fail to support the social brain hypothesis but provide important empirical support for the relationship between relative brain size and the ability to solve this novel technical problem. PMID:26811470

  7. Brain size predicts problem-solving ability in mammalian carnivores.

    PubMed

    Benson-Amram, Sarah; Dantzer, Ben; Stricker, Gregory; Swanson, Eli M; Holekamp, Kay E

    2016-03-01

    Despite considerable interest in the forces shaping the relationship between brain size and cognitive abilities, it remains controversial whether larger-brained animals are, indeed, better problem-solvers. Recently, several comparative studies have revealed correlations between brain size and traits thought to require advanced cognitive abilities, such as innovation, behavioral flexibility, invasion success, and self-control. However, the general assumption that animals with larger brains have superior cognitive abilities has been heavily criticized, primarily because of the lack of experimental support for it. Here, we designed an experiment to inquire whether specific neuroanatomical or socioecological measures predict success at solving a novel technical problem among species in the mammalian order Carnivora. We presented puzzle boxes, baited with food and scaled to accommodate body size, to members of 39 carnivore species from nine families housed in multiple North American zoos. We found that species with larger brains relative to their body mass were more successful at opening the boxes. In a subset of species, we also used virtual brain endocasts to measure volumes of four gross brain regions and show that some of these regions improve model prediction of success at opening the boxes when included with total brain size and body mass. Socioecological variables, including measures of social complexity and manual dexterity, failed to predict success at opening the boxes. Our results, thus, fail to support the social brain hypothesis but provide important empirical support for the relationship between relative brain size and the ability to solve this novel technical problem.

  8. Whole Brain Size and General Mental Ability: A Review

    PubMed Central

    Rushton, J. Philippe; Ankney, C. Davison

    2009-01-01

    We review the literature on the relation between whole brain size and general mental ability (GMA) both within and between species. Among humans, in 28 samples using brain imaging techniques, the mean brain size/GMA correlation is 0.40 (N = 1,389; p < 10−10); in 59 samples using external head size measures it is 0.20 (N = 63,405; p < 10−10). In 6 samples using the method of correlated vectors to distill g, the general factor of mental ability, the mean r is 0.63. We also describe the brain size/GMA correlations with age, socioeconomic position, sex, and ancestral population groups, which also provide information about brain–behavior relationships. Finally, we examine brain size and mental ability from an evolutionary and behavior genetic perspective. PMID:19283594

  9. Neanderthal brain size at birth provides insights into the evolution of human life history

    PubMed Central

    Ponce de León, Marcia S.; Golovanova, Lubov; Doronichev, Vladimir; Romanova, Galina; Akazawa, Takeru; Kondo, Osamu; Ishida, Hajime; Zollikofer, Christoph P. E.

    2008-01-01

    From birth to adulthood, the human brain expands by a factor of 3.3, compared with 2.5 in chimpanzees [DeSilva J and Lesnik J (2006) Chimpanzee neonatal brain size: Implications for brain growth in Homo erectus. J Hum Evol 51: 207–212]. How the required extra amount of human brain growth is achieved and what its implications are for human life history and cognitive development are still a matter of debate. Likewise, because comparative fossil evidence is scarce, when and how the modern human pattern of brain growth arose during evolution is largely unknown. Virtual reconstructions of a Neanderthal neonate from Mezmaiskaya Cave (Russia) and of two Neanderthal infant skeletons from Dederiyeh Cave (Syria) now provide new comparative insights: Neanderthal brain size at birth was similar to that in recent Homo sapiens and most likely subject to similar obstetric constraints. Neanderthal brain growth rates during early infancy were higher, however. This pattern of growth resulted in larger adult brain sizes but not in earlier completion of brain growth. Because large brains growing at high rates require large, late-maturing, mothers [Leigh SR and Blomquist GE (2007) in Campbell CJ et al. Primates in perspective; pp 396–407], it is likely that Neanderthal life history was similarly slow, or even slower-paced, than in recent H. sapiens. PMID:18779579

  10. The evolutionary history of cetacean brain and body size.

    PubMed

    Montgomery, Stephen H; Geisler, Jonathan H; McGowen, Michael R; Fox, Charlotte; Marino, Lori; Gatesy, John

    2013-11-01

    Cetaceans rival primates in brain size relative to body size and include species with the largest brains and biggest bodies to have ever evolved. Cetaceans are remarkably diverse, varying in both phenotypes by several orders of magnitude, with notable differences between the two extant suborders, Mysticeti and Odontoceti. We analyzed the evolutionary history of brain and body mass, and relative brain size measured by the encephalization quotient (EQ), using a data set of extinct and extant taxa to capture temporal variation in the mode and direction of evolution. Our results suggest that cetacean brain and body mass evolved under strong directional trends to increase through time, but decreases in EQ were widespread. Mysticetes have significantly lower EQs than odontocetes due to a shift in brain:body allometry following the divergence of the suborders, caused by rapid increases in body mass in Mysticeti and a period of body mass reduction in Odontoceti. The pattern in Cetacea contrasts with that in primates, which experienced strong trends to increase brain mass and relative brain size, but not body mass. We discuss what these analyses reveal about the convergent evolution of large brains, and highlight that until recently the most encephalized mammals were odontocetes, not primates. PMID:24152011

  11. The evolutionary history of cetacean brain and body size.

    PubMed

    Montgomery, Stephen H; Geisler, Jonathan H; McGowen, Michael R; Fox, Charlotte; Marino, Lori; Gatesy, John

    2013-11-01

    Cetaceans rival primates in brain size relative to body size and include species with the largest brains and biggest bodies to have ever evolved. Cetaceans are remarkably diverse, varying in both phenotypes by several orders of magnitude, with notable differences between the two extant suborders, Mysticeti and Odontoceti. We analyzed the evolutionary history of brain and body mass, and relative brain size measured by the encephalization quotient (EQ), using a data set of extinct and extant taxa to capture temporal variation in the mode and direction of evolution. Our results suggest that cetacean brain and body mass evolved under strong directional trends to increase through time, but decreases in EQ were widespread. Mysticetes have significantly lower EQs than odontocetes due to a shift in brain:body allometry following the divergence of the suborders, caused by rapid increases in body mass in Mysticeti and a period of body mass reduction in Odontoceti. The pattern in Cetacea contrasts with that in primates, which experienced strong trends to increase brain mass and relative brain size, but not body mass. We discuss what these analyses reveal about the convergent evolution of large brains, and highlight that until recently the most encephalized mammals were odontocetes, not primates.

  12. Brain size of Homo floresiensis and its evolutionary implications.

    PubMed

    Kubo, Daisuke; Kono, Reiko T; Kaifu, Yousuke

    2013-06-01

    The extremely small endocranial volume (ECV) of LB1, the type specimen of Homo floresiensis, poses a challenge in our understanding of human brain evolution. Some researchers hypothesize dramatic dwarfing of relative brain size from Homo erectus presumably without significant decrease in intellectual function, whereas others expect a lesser degree of brain diminution from a more primitive, small-brained form of hominin currently undocumented in eastern Asia. However, inconsistency in the published ECVs for LB1 (380-430 cc), unclear human intraspecific brain-body size scaling and other uncertainties have hampered elaborative modelling of its brain size reduction. In this study, we accurately determine the ECV of LB1 using high-resolution micro-CT scan. The ECV of LB1 thus measured, 426 cc, is larger than the commonly cited figure in previous studies (400 cc). Coupled with brain-body size correlation in Homo sapiens calculated based on a sample from 20 worldwide modern human populations, we construct new models of the brain size reduction in the evolution of H. floresiensis. The results show a more significant contribution of scaling effect than previously claimed. PMID:23595271

  13. Brain size-related breeding strategies in a seabird.

    PubMed

    Jaatinen, Kim; Öst, Markus

    2016-01-01

    The optimal compromise between decision speed and accuracy may depend on cognitive ability, associated with the degree of encephalization: larger brain size may select for accurate but slow decision-making, beneficial under challenging conditions but costly under benign ones. How this brain size-dependent selection pressure shapes avian breeding phenology and reproductive performance remains largely unexplored. We predicted that (1) large-brained individuals have a delayed breeding schedule due to thorough nest-site selection and/or prolonged resource acquisition, (2) good condition facilitates early breeding independent of relative brain size, and (3) large brain size accrues benefits mainly to individuals challenged by environmental or intrinsic constraints. To test these predictions, we examined how the relative head volume of female eiders (Somateria mollissima) of variable body condition correlated with their breeding schedule, hatching success and offspring quality. The results were consistent with our predictions. First, large head size was associated with a progressively later onset of breeding with increasing breeding dispersal distance. Second, increasing body condition advanced the timing of breeding, but this effect was significantly weaker in large-brained females. Third, larger head volume was associated with increased hatching success mainly among late breeders and those in poor body condition, and duckling body condition was positively related to maternal head volume, but only in poor-condition mothers. Our study is, to our knowledge, the first to demonstrate the presence of brain size-related differences in reproductive strategies within a single natural population.

  14. Experience-Dependent Neural Plasticity in the Adult Damaged Brain

    ERIC Educational Resources Information Center

    Kerr, Abigail L.; Cheng, Shao-Ying; Jones, Theresa A.

    2011-01-01

    Behavioral experience is at work modifying the structure and function of the brain throughout the lifespan, but it has a particularly dramatic influence after brain injury. This review summarizes recent findings on the role of experience in reorganizing the adult damaged brain, with a focus on findings from rodent stroke models of chronic upper…

  15. Stem Cell-Mediated Regeneration of the Adult Brain

    PubMed Central

    Jessberger, Sebastian

    2016-01-01

    Acute or chronic injury of the adult mammalian brain is often associated with persistent functional deficits as its potential for regeneration and capacity to rebuild lost neural structures is limited. However, the discovery that neural stem cells (NSCs) persist throughout life in discrete regions of the brain, novel approaches to induce the formation of neuronal and glial cells, and recently developed strategies to generate tissue for exogenous cell replacement strategies opened novel perspectives how to regenerate the adult brain. Here, we will review recently developed approaches for brain repair and discuss future perspectives that may eventually allow for developing novel treatment strategies in acute and chronic brain injury. PMID:27781019

  16. The effects of laboratory housing and spatial enrichment on brain size and metabolic rate in the eastern mosquitofish, Gambusia holbrooki.

    PubMed

    Turschwell, Mischa P; White, Craig R

    2016-01-01

    It has long been hypothesised that there is a functional correlation between brain size and metabolic rate in vertebrates. The present study tested this hypothesis in wild-caught adult mosquitofish Gambusia holbrooki by testing for an intra-specific association between resting metabolic rate (RMR) and brain size while controlling for variation in body size, and through the examination of the effects of spatial enrichment and laboratory housing on body mass-independent measures of brain size and RMR. Controlling for body mass, there was no relationship between brain size and RMR in wild-caught fish. Contrary to predictions, spatial enrichment caused a decrease in mass-independent brain size, highlighting phenotypic plasticity in the adult brain. As expected, after controlling for differences in body size, wild-caught fish had relatively larger brains than fish that had been maintained in the laboratory for a minimum of six weeks, but wild-caught fish also had significantly lower mass-independent RMR. This study demonstrates that an organisms' housing environment can cause significant plastic changes to fitness related traits including brain size and RMR. We therefore conclude that current standard laboratory housing conditions may cause captive animals to be non-representative of their wild counterparts, potentially undermining the transferability of previous laboratory-based studies of aquatic ectothermic vertebrates to wild populations. PMID:26794608

  17. The effects of laboratory housing and spatial enrichment on brain size and metabolic rate in the eastern mosquitofish, Gambusia holbrooki

    PubMed Central

    Turschwell, Mischa P.; White, Craig R.

    2016-01-01

    ABSTRACT It has long been hypothesised that there is a functional correlation between brain size and metabolic rate in vertebrates. The present study tested this hypothesis in wild-caught adult mosquitofish Gambusia holbrooki by testing for an intra-specific association between resting metabolic rate (RMR) and brain size while controlling for variation in body size, and through the examination of the effects of spatial enrichment and laboratory housing on body mass-independent measures of brain size and RMR. Controlling for body mass, there was no relationship between brain size and RMR in wild-caught fish. Contrary to predictions, spatial enrichment caused a decrease in mass-independent brain size, highlighting phenotypic plasticity in the adult brain. As expected, after controlling for differences in body size, wild-caught fish had relatively larger brains than fish that had been maintained in the laboratory for a minimum of six weeks, but wild-caught fish also had significantly lower mass-independent RMR. This study demonstrates that an organisms' housing environment can cause significant plastic changes to fitness related traits including brain size and RMR. We therefore conclude that current standard laboratory housing conditions may cause captive animals to be non-representative of their wild counterparts, potentially undermining the transferability of previous laboratory-based studies of aquatic ectothermic vertebrates to wild populations. PMID:26794608

  18. Brain mass and cranial nerve size in shrews and moles.

    PubMed

    Leitch, Duncan B; Sarko, Diana K; Catania, Kenneth C

    2014-09-01

    We investigated the relationship between body size, brain size, and fibers in selected cranial nerves in shrews and moles. Species include tiny masked shrews (S. cinereus) weighing only a few grams and much larger mole species weighing up to 90 grams. It also includes closely related species with very different sensory specializations - such as the star-nosed mole and the common, eastern mole. We found that moles and shrews have tiny optic nerves with fiber counts not correlated with body or brain size. Auditory nerves were similarly small but increased in fiber number with increasing brain and body size. Trigeminal nerve number was by far the largest and also increased with increasing brain and body size. The star-nosed mole was an outlier, with more than twice the number of trigeminal nerve fibers than any other species. Despite this hypertrophied cranial nerve, star-nosed mole brains were not larger than predicted from body size, suggesting that magnification of their somatosensory systems does not result in greater overall CNS size.

  19. Brain Mass and Cranial Nerve Size in Shrews and Moles

    PubMed Central

    Leitch, Duncan B.; Sarko, Diana K.; Catania, Kenneth C.

    2014-01-01

    We investigated the relationship between body size, brain size, and fibers in selected cranial nerves in shrews and moles. Species include tiny masked shrews (S. cinereus) weighing only a few grams and much larger mole species weighing up to 90 grams. It also includes closely related species with very different sensory specializations – such as the star-nosed mole and the common, eastern mole. We found that moles and shrews have tiny optic nerves with fiber counts not correlated with body or brain size. Auditory nerves were similarly small but increased in fiber number with increasing brain and body size. Trigeminal nerve number was by far the largest and also increased with increasing brain and body size. The star-nosed mole was an outlier, with more than twice the number of trigeminal nerve fibers than any other species. Despite this hypertrophied cranial nerve, star-nosed mole brains were not larger than predicted from body size, suggesting that magnification of their somatosensory systems does not result in greater overall CNS size. PMID:25174995

  20. Dendritic development of newly generated neurons in the adult brain.

    PubMed

    Ribak, Charles E; Shapiro, Lee A

    2007-10-01

    Ramon y Cajal described the fundamental morphology of the dendritic and axonal growth cones of neurons during development. However, technical limitations at the time prevented him from describing such growth cones from newborn neurons in the adult brain. The phenomenon of adult neurogenesis is briefly reviewed, and the structural description of dendritic and axonal outgrowth for these newly generated neurons in the adult brain is discussed. Axonal outgrowth into the hilus and CA3 region of the hippocampus occurs later than the outgrowth of dendrites into the molecular layer, and the ultrastructural analysis of axonal outgrowth has yet to be completed. In contrast, growth cones on dendrites from newborn neurons in the adult dentate gyrus have been described and this observation suggests that dendrites in adult brains grow in a similar way to those found in immature brains. However, dendrites in adult brains have to navigate through a denser neuropil and a more complex cell layer. Therefore, some aspects of dendritic outgrowth of neurons born in the adult dentate gyrus are different as compared to that found in development. These differences include the radial process of radial glial cells acting as a lattice to guide apical dendritic growth through the granule cell layer and a much thinner dendrite to grow through the neuropil of the molecular layer. Therefore, similarities and differences exist for dendritic outgrowth from newborn neurons in the developing and adult brain.

  1. Brain size and social complexity: a computed tomography study in Hyaenidae.

    PubMed

    Sakai, Sharleen T; Arsznov, Bradley M; Lundrigan, Barbara L; Holekamp, Kay E

    2011-01-01

    The social brain hypothesis posits that the demands of living in complex social groups require increased neural processing, and that this underlies the expansion of brain areas involved in mediation of complex social behavior. However, much of the support for the social brain hypothesis is derived from comparative studies in primates. If large brains evolved as a result of selection pressures imposed by life within complex societies, as the social brain hypothesis predicts, then gregarious nonprimate species should possess large brains and exhibit comparable expansion of brain areas mediating social behavior. Our purpose here was to test a prediction of the social brain hypothesis-- that increased brain size is related to social complexity --by examining species in the carnivore family Hyaenidae. Hyaenidae contains 4 extant species that span a spectrum of social complexity: the aardwolf (Proteles cristata) is solitary during the nonbreeding season, and forms monogamous pairs during the breeding season; the striped hyena (Hyaena hyaena) lives solitarily or in small groups; the brown hyena (Parahyaena brunnea) lives in groups of up to 14 individuals; and the spotted hyena (Crocuta crocuta) lives in complex hierarchically organized groups containing up to 90 animals. Computed tomography was used to create three-dimensional endocasts based on serial analysis of coronal sections of the adult endocranium. The largest brain volume, relative to body size, is found in the spotted hyena. We found no significant variation in relative brain volume among striped hyenas, brown hyenas, and aardwolves. The spotted hyena also possesses a larger anterior cerebrum volume relative to total brain volume than is found in the other hyena species; this region is composed primarily of frontal cortex. These data are consistent with the idea that expansion of the frontal cortex is driven by the demands of processing cognitive information associated with complex social lives, but other

  2. Brain size and social complexity: a computed tomography study in Hyaenidae.

    PubMed

    Sakai, Sharleen T; Arsznov, Bradley M; Lundrigan, Barbara L; Holekamp, Kay E

    2011-01-01

    The social brain hypothesis posits that the demands of living in complex social groups require increased neural processing, and that this underlies the expansion of brain areas involved in mediation of complex social behavior. However, much of the support for the social brain hypothesis is derived from comparative studies in primates. If large brains evolved as a result of selection pressures imposed by life within complex societies, as the social brain hypothesis predicts, then gregarious nonprimate species should possess large brains and exhibit comparable expansion of brain areas mediating social behavior. Our purpose here was to test a prediction of the social brain hypothesis-- that increased brain size is related to social complexity --by examining species in the carnivore family Hyaenidae. Hyaenidae contains 4 extant species that span a spectrum of social complexity: the aardwolf (Proteles cristata) is solitary during the nonbreeding season, and forms monogamous pairs during the breeding season; the striped hyena (Hyaena hyaena) lives solitarily or in small groups; the brown hyena (Parahyaena brunnea) lives in groups of up to 14 individuals; and the spotted hyena (Crocuta crocuta) lives in complex hierarchically organized groups containing up to 90 animals. Computed tomography was used to create three-dimensional endocasts based on serial analysis of coronal sections of the adult endocranium. The largest brain volume, relative to body size, is found in the spotted hyena. We found no significant variation in relative brain volume among striped hyenas, brown hyenas, and aardwolves. The spotted hyena also possesses a larger anterior cerebrum volume relative to total brain volume than is found in the other hyena species; this region is composed primarily of frontal cortex. These data are consistent with the idea that expansion of the frontal cortex is driven by the demands of processing cognitive information associated with complex social lives, but other

  3. Constraints on the adult-offspring size relationship in protists.

    PubMed

    Caval-Holme, Franklin; Payne, Jonathan; Skotheim, Jan M

    2013-12-01

    The relationship between adult and offspring size is an important aspect of reproductive strategy. Although this filial relationship has been extensively examined in plants and animals, we currently lack comparable data for protists, whose strategies may differ due to the distinct ecological and physiological constraints on single-celled organisms. Here, we report measurements of adult and offspring sizes in 3888 species and subspecies of foraminifera, a class of large marine protists. Foraminifera exhibit a wide range of reproductive strategies; species of similar adult size may have offspring whose sizes vary 100-fold. Yet, a robust pattern emerges. The minimum (5th percentile), median, and maximum (95th percentile) offspring sizes exhibit a consistent pattern of increase with adult size independent of environmental change and taxonomic variation over the past 400 million years. The consistency of this pattern may arise from evolutionary optimization of the offspring size-fecundity trade-off and/or from cell-biological constraints that limit the range of reproductive strategies available to single-celled organisms. When compared with plants and animals, foraminifera extend the evidence that offspring size covaries with adult size across an additional five orders of magnitude in organism size.

  4. ARTIFICIAL SELECTION ON RELATIVE BRAIN SIZE REVEALS A POSITIVE GENETIC CORRELATION BETWEEN BRAIN SIZE AND PROACTIVE PERSONALITY IN THE GUPPY

    PubMed Central

    Kotrschal, Alexander; Lievens, Eva JP; Dahlbom, Josefin; Bundsen, Andreas; Semenova, Svetlana; Sundvik, Maria; Maklakov, Alexei A; Winberg, Svante; Panula, Pertti; Kolm, Niclas; Morrow, E

    2014-01-01

    Animal personalities range from individuals that are shy, cautious, and easily stressed (a “reactive” personality type) to individuals that are bold, innovative, and quick to learn novel tasks, but also prone to routine formation (a “proactive” personality type). Although personality differences should have important consequences for fitness, their underlying mechanisms remain poorly understood. Here, we investigated how genetic variation in brain size affects personality. We put selection lines of large- and small-brained guppies (Poecilia reticulata), with known differences in cognitive ability, through three standard personality assays. First, we found that large-brained animals were faster to habituate to, and more exploratory in, open field tests. Large-brained females were also bolder. Second, large-brained animals excreted less cortisol in a stressful situation (confinement). Third, large-brained animals were slower to feed from a novel food source, which we interpret as being caused by reduced behavioral flexibility rather than lack of innovation in the large-brained lines. Overall, the results point toward a more proactive personality type in large-brained animals. Thus, this study provides the first experimental evidence linking brain size and personality, an interaction that may affect important fitness-related aspects of ecology such as dispersal and niche exploration. PMID:24359469

  5. Artificial selection on relative brain size reveals a positive genetic correlation between brain size and proactive personality in the guppy.

    PubMed

    Kotrschal, Alexander; Lievens, Eva J P; Dahlbom, Josefin; Bundsen, Andreas; Semenova, Svetlana; Sundvik, Maria; Maklakov, Alexei A; Winberg, Svante; Panula, Pertti; Kolm, Niclas

    2014-04-01

    Animal personalities range from individuals that are shy, cautious, and easily stressed (a "reactive" personality type) to individuals that are bold, innovative, and quick to learn novel tasks, but also prone to routine formation (a "proactive" personality type). Although personality differences should have important consequences for fitness, their underlying mechanisms remain poorly understood. Here, we investigated how genetic variation in brain size affects personality. We put selection lines of large- and small-brained guppies (Poecilia reticulata), with known differences in cognitive ability, through three standard personality assays. First, we found that large-brained animals were faster to habituate to, and more exploratory in, open field tests. Large-brained females were also bolder. Second, large-brained animals excreted less cortisol in a stressful situation (confinement). Third, large-brained animals were slower to feed from a novel food source, which we interpret as being caused by reduced behavioral flexibility rather than lack of innovation in the large-brained lines. Overall, the results point toward a more proactive personality type in large-brained animals. Thus, this study provides the first experimental evidence linking brain size and personality, an interaction that may affect important fitness-related aspects of ecology such as dispersal and niche exploration. PMID:24359469

  6. Targeted taste cell-specific overexpression of brain-derived neurotrophic factor in adult taste buds elevates phosphorylated TrkB protein levels in taste cells, increases taste bud size, and promotes gustatory innervation.

    PubMed

    Nosrat, Irina V; Margolskee, Robert F; Nosrat, Christopher A

    2012-05-11

    Brain-derived neurotrophic factor (BDNF) is the most potent neurotrophic factor in the peripheral taste system during embryonic development. It is also expressed in adult taste buds. There is a lack of understanding of the role of BDNF in the adult taste system. To address this, we generated novel transgenic mice in which transgene expression was driven by an α-gustducin promoter coupling BDNF expression to the postnatal expression of gustducin in taste cells. Immunohistochemistry revealed significantly stronger BDNF labeling in taste cells of high BDNF-expressing mouse lines compared with controls. We show that taste buds in these mice are significantly larger and have a larger number of taste cells compared with controls. To examine whether innervation was affected in Gust-BDNF mice, we used antibodies to neural cell adhesion molecule (NCAM) and ATP receptor P2X3. The total density of general innervation and specifically the gustatory innervation was markedly increased in high BDNF-expressing mice compared with controls. TrkB and NCAM gene expression in laser capture microdissected taste epithelia were significantly up-regulated in these mice. Up-regulation of TrkB transcripts in taste buds and elevated taste cell-specific TrkB phosphorylation in response to increased BDNF levels indicate that BDNF controls the expression and activation of its high affinity receptor in taste cells. This demonstrates a direct taste cell function for BDNF. BDNF also orchestrates and maintains taste bud innervation. We propose that the Gust-BDNF transgenic mouse models can be employed to further dissect the specific roles of BDNF in the adult taste system. PMID:22442142

  7. Specialization and group size: brain and behavioural correlates of colony size in ants lacking morphological castes

    PubMed Central

    Amador-Vargas, Sabrina; Gronenberg, Wulfila; Wcislo, William T.; Mueller, Ulrich

    2015-01-01

    Group size in both multicellular organisms and animal societies can correlate with the degree of division of labour. For ants, the task specialization hypothesis (TSH) proposes that increased behavioural specialization enabled by larger group size corresponds to anatomical specialization of worker brains. Alternatively, the social brain hypothesis proposes that increased levels of social stimuli in larger colonies lead to enlarged brain regions in all workers, regardless of their task specialization. We tested these hypotheses in acacia ants (Pseudomyrmex spinicola), which exhibit behavioural but not morphological task specialization. In wild colonies, we marked, followed and tested ant workers involved in foraging tasks on the leaves (leaf-ants) and in defensive tasks on the host tree trunk (trunk-ants). Task specialization increased with colony size, especially in defensive tasks. The relationship between colony size and brain region volume was task-dependent, supporting the TSH. Specifically, as colony size increased, the relative size of regions within the mushroom bodies of the brain decreased in trunk-ants but increased in leaf-ants; those regions play important roles in learning and memory. Our findings suggest that workers specialized in defence may have reduced learning abilities relative to leaf-ants; these inferences remain to be tested. In societies with monomorphic workers, brain polymorphism enhanced by group size could be a mechanism by which division of labour is achieved. PMID:25567649

  8. Specialization and group size: brain and behavioural correlates of colony size in ants lacking morphological castes.

    PubMed

    Amador-Vargas, Sabrina; Gronenberg, Wulfila; Wcislo, William T; Mueller, Ulrich

    2015-02-22

    Group size in both multicellular organisms and animal societies can correlate with the degree of division of labour. For ants, the task specialization hypothesis (TSH) proposes that increased behavioural specialization enabled by larger group size corresponds to anatomical specialization of worker brains. Alternatively, the social brain hypothesis proposes that increased levels of social stimuli in larger colonies lead to enlarged brain regions in all workers, regardless of their task specialization. We tested these hypotheses in acacia ants (Pseudomyrmex spinicola), which exhibit behavioural but not morphological task specialization. In wild colonies, we marked, followed and tested ant workers involved in foraging tasks on the leaves (leaf-ants) and in defensive tasks on the host tree trunk (trunk-ants). Task specialization increased with colony size, especially in defensive tasks. The relationship between colony size and brain region volume was task-dependent, supporting the TSH. Specifically, as colony size increased, the relative size of regions within the mushroom bodies of the brain decreased in trunk-ants but increased in leaf-ants; those regions play important roles in learning and memory. Our findings suggest that workers specialized in defence may have reduced learning abilities relative to leaf-ants; these inferences remain to be tested. In societies with monomorphic workers, brain polymorphism enhanced by group size could be a mechanism by which division of labour is achieved.

  9. Size-optimized 32-Channel Brain Arrays for 3 T Pediatric Imaging

    PubMed Central

    Keil, Boris; Alagappan, Vijay; Mareyam, Azma; McNab, Jennifer A.; Fujimoto, Kyoko; Tountcheva, Veneta; Triantafyllou, Christina; Dilks, Daniel D.; Kanwisher, Nancy; Lin, Weili; Grant, P. Ellen; Wald, Lawrence L.

    2011-01-01

    Size-optimized 32-channel receive array coils were developed for five age groups, neonates, 6 months old, 1 year old, 4 years old, and 7 years old, and evaluated for pediatric brain imaging. The array consisted of overlapping circular surface coils laid out on a close-fitting coil-former. The two-section coil former design was obtained from surface contours of aligned three-dimensional MRI scans of each age group. Signal-to-noise ratio and noise amplification for parallel imaging were evaluated and compared to two coils routinely used for pediatric brain imaging; a commercially available 32-channel adult head coil and a pediatric-sized birdcage coil. Phantom measurements using the neonate, 6-month-old, 1-year-old, 4-year-old, and 7-year-old coils showed signal-to-noise ratio increases at all locations within the brain over the comparison coils. Within the brain cortex the five dedicated pediatric arrays increased signal-to-noise ratio by up to 3.6-, 3.0-, 2.6-, 2.3-, and 1.7-fold, respectively, compared to the 32-channel adult coil, as well as improved G-factor maps for accelerated imaging. This study suggests that a size-tailored approach can provide significant sensitivity gains for accelerated and unaccelerated pediatric brain imaging. PMID:21656548

  10. Guidelines for Better Communication with Brain Impaired Adults

    MedlinePlus

    ... A You are here Home Guidelines for Better Communication with Brain Impaired Adults Printer-friendly version Communicating ... easy solutions, following some basic guidelines should ease communication, and lower levels of stress both for you ...

  11. Critical care management of severe traumatic brain injury in adults

    PubMed Central

    2012-01-01

    Traumatic brain injury (TBI) is a major medical and socio-economic problem, and is the leading cause of death in children and young adults. The critical care management of severe TBI is largely derived from the "Guidelines for the Management of Severe Traumatic Brain Injury" that have been published by the Brain Trauma Foundation. The main objectives are prevention and treatment of intracranial hypertension and secondary brain insults, preservation of cerebral perfusion pressure (CPP), and optimization of cerebral oxygenation. In this review, the critical care management of severe TBI will be discussed with focus on monitoring, avoidance and minimization of secondary brain insults, and optimization of cerebral oxygenation and CPP. PMID:22304785

  12. Cell proliferation and neurogenesis in adult mouse brain.

    PubMed

    Bordiuk, Olivia L; Smith, Karen; Morin, Peter J; Semënov, Mikhail V

    2014-01-01

    Neurogenesis, the formation of new neurons, can be observed in the adult brain of many mammalian species, including humans. Despite significant progress in our understanding of adult neurogenesis, we are still missing data about the extent and location of production of neural precursors in the adult mammalian brain. We used 5-ethynyl-2'-deoxyuridine (EdU) to map the location of proliferating cells throughout the entire adult mouse brain and found that neurogenesis occurs at two locations in the mouse brain. The larger one we define as the main proliferative zone (MPZ), and the smaller one corresponds to the subgranular zone of the hippocampus. The MPZ can be divided into three parts. The caudate migratory stream (CMS) occupies the middle part of the MPZ. The cable of proliferating cells emanating from the most anterior part of the CMS toward the olfactory bulbs forms the rostral migratory stream. The thin layer of proliferating cells extending posteriorly from the CMS forms the midlayer. We have not found any additional aggregations of proliferating cells in the adult mouse brain that could suggest the existence of other major neurogenic zones in the adult mouse brain.

  13. Cell proliferation and neurogenesis in adult mouse brain.

    PubMed

    Bordiuk, Olivia L; Smith, Karen; Morin, Peter J; Semënov, Mikhail V

    2014-01-01

    Neurogenesis, the formation of new neurons, can be observed in the adult brain of many mammalian species, including humans. Despite significant progress in our understanding of adult neurogenesis, we are still missing data about the extent and location of production of neural precursors in the adult mammalian brain. We used 5-ethynyl-2'-deoxyuridine (EdU) to map the location of proliferating cells throughout the entire adult mouse brain and found that neurogenesis occurs at two locations in the mouse brain. The larger one we define as the main proliferative zone (MPZ), and the smaller one corresponds to the subgranular zone of the hippocampus. The MPZ can be divided into three parts. The caudate migratory stream (CMS) occupies the middle part of the MPZ. The cable of proliferating cells emanating from the most anterior part of the CMS toward the olfactory bulbs forms the rostral migratory stream. The thin layer of proliferating cells extending posteriorly from the CMS forms the midlayer. We have not found any additional aggregations of proliferating cells in the adult mouse brain that could suggest the existence of other major neurogenic zones in the adult mouse brain. PMID:25375658

  14. Memory and Brain Volume in Adults Prenatally Exposed to Alcohol

    ERIC Educational Resources Information Center

    Coles, Claire D.; Goldstein, Felicia C.; Lynch, Mary Ellen; Chen, Xiangchuan; Kable, Julie A.; Johnson, Katrina C.; Hu, Xiaoping

    2011-01-01

    The impact of prenatal alcohol exposure on memory and brain development was investigated in 92 African-American, young adults who were first identified in the prenatal period. Three groups (Control, n = 26; Alcohol-related Neurodevelopmental Disorder, n = 36; and Dysmorphic, n = 30) were imaged using structural MRI with brain volume calculated for…

  15. Childhood Onset Schizophrenia: Cortical Brain Abnormalities as Young Adults

    ERIC Educational Resources Information Center

    Greenstein, Deanna; Lerch, Jason; Shaw, Philip; Clasen, Liv; Giedd, Jay; Gochman, Peter; Rapoport, Judith; Gogtay, Nitin

    2006-01-01

    Background: Childhood onset schizophrenia (COS) is a rare but severe form of the adult onset disorder. While structural brain imaging studies show robust, widespread, and progressive gray matter loss in COS during adolescence, there have been no longitudinal studies of sufficient duration to examine comparability with the more common adult onset…

  16. A phylogenetic analysis of egg size, clutch size, spawning mode, adult body size, and latitude in reef fishes

    NASA Astrophysics Data System (ADS)

    Kasimatis, Katja; Riginos, Cynthia

    2016-06-01

    Theoretical treatments of egg size in fishes suggest that constraints on reproductive output should create trade-offs between the size and number of eggs produced per spawn. For marine reef fishes, the observation of distinct reproductive care strategies (demersal guarding, egg scattering, and pelagic spawning) has additionally prompted speculation that these strategies reflect alternative fitness optima with selection on egg size differing by reproductive mode and perhaps latitude. Here, we aggregate data from 278 reef fish species and test whether clutch size, reproductive care, adult body size, and latitudinal bands (i.e., tropical, subtropical, and temperate) predict egg size, using a statistically unified framework that accounts for phylogenetic correlations among traits. We find no inverse relationship between species egg size and clutch size, but rather that egg size differs by reproductive mode (mean volume for demersal eggs = 1.22 mm3, scattered eggs = 0.18 mm3, pelagic eggs = 0.52 mm3) and that clutch size is strongly correlated with adult body size. Larger eggs were found in temperate species compared with tropical species in both demersal guarders and pelagic spawners, but this difference was not strong when accounting for phylogenetic correlations, suggesting that differences in species composition underlies regional differences in egg size. In summary, demersal guarders are generally small fishes with small clutch sizes that produce large eggs. Pelagic spawners and egg scatterers are variable in adult and clutch size. Although pelagic spawned eggs are variable in size, those of scatterers are consistently small.

  17. Genome size is inversely correlated with relative brain size in parrots and cockatoos.

    PubMed

    Andrews, Chandler B; Gregory, T Ryan

    2009-03-01

    Genome size (haploid nuclear DNA content) has been found to correlate positively with cell size and negatively with cell division rate in a variety of taxa. These cytological relationships manifest in various ways at the organism level, for example, in terms of body size, metabolic rate, or developmental rate, depending on the biology of the organisms. In birds, it has been suggested that high metabolic rate and strong flight ability are linked to small genome size. However, it was also hypothesized that the exceptional cognitive abilities of birds may impose additional constraints on genome size through effects on neuron size and differentiation, as has been observed in amphibians. To test this hypothesis, a comparative analysis was made between genome size, cell (erythrocyte) size, and brain size in 54 species of parrots and cockatoos (order Psittaciformes, family Psittacidae). Relative brain volume, which is taken as an indicator of investment in brain tissue and is widely correlated with behavioural and ecological traits, was found to correlate inversely with genome size. Several possible and mutually compatible explanations for this relationship are described.

  18. Acrobatic courtship display coevolves with brain size in manakins (Pipridae).

    PubMed

    Lindsay, Willow R; Houck, Justin T; Giuliano, Claire E; Day, Lainy B

    2015-01-01

    Acrobatic display behaviour is sexually selected in manakins (Pipridae) and can place high demands on many neural systems. Manakin displays vary across species in terms of behavioural complexity, differing in number of unique motor elements, production of mechanical sounds, cooperation between displaying males, and construction of the display site. Historically, research emphasis has been placed on neurological specializations for vocal aspects of courtship, and less is known about the control of physical, non-vocal displays. By examining brain evolution in relation to extreme acrobatic feats such as manakin displays, we can vastly expand our knowledge of how sexual selection acts on motor behaviour. We tested the hypothesis that sexual selection for complex motor displays has selected for larger brains across the Pipridae. We found that display complexity positively predicts relative brain weight (adjusted for body size) after controlling for phylogeny in 12 manakin species and a closely related flycatcher. This evidence suggests that brain size has evolved in response to sexual selection to facilitate aspects of display such as motor, sensorimotor, perceptual, and cognitive abilities. We show, for the first time, that sexual selection for acrobatic motor behaviour can drive brain size evolution in avian species and, in particular, a family of suboscine birds. PMID:25660714

  19. Neural stem cells in the adult human brain

    PubMed Central

    Gonzalez-Perez, Oscar

    2012-01-01

    For decades, it was believed that the adult brain was a quiescent organ unable to produce new neurons. At the beginning of the1960's, this dogma was challenged by a small group of neuroscientists. To date, it is well-known that new neurons are generated in the adult brain throughout life. Adult neurogenesis is primary confined to the subventricular zone (SVZ) of the forebrain and the subgranular zone of the dentate gyrus within the hippocampus. In both the human and the rodent brain, the primary progenitor of adult SVZ is a subpopulation of astrocytes that have stem-cell-like features. The human SVZ possesses a peculiar cell composition and displays important organizational differences when compared to the SVZ of other mammals. Some evidence suggests that the human SVZ may be not only an endogenous source of neural precursor cells for brain repair, but also a source of brain tumors. In this review, we described the cytoarchitecture and cellular composition of the SVZ in the adult human brain. We also discussed some clinical implications of SVZ, such as: stem-cell-based therapies against neurodegenerative diseases and its potential as a source of malignant cells. Understanding the biology of human SVZ and its neural progenitors is one of the crucial steps to develop novel therapies against neurological diseases in humans. PMID:23181200

  20. Brain stem auditory evoked responses in human infants and adults

    NASA Technical Reports Server (NTRS)

    Hecox, K.; Galambos, R.

    1974-01-01

    Brain stem evoked potentials were recorded by conventional scalp electrodes in infants (3 weeks to 3 years of age) and adults. The latency of one of the major response components (wave V) is shown to be a function both of click intensity and the age of the subject; this latency at a given signal strength shortens postnatally to reach the adult value (about 6 msec) by 12 to 18 months of age. The demonstrated reliability and limited variability of these brain stem electrophysiological responses provide the basis for an optimistic estimate of their usefulness as an objective method for assessing hearing in infants and adults.

  1. A role for brain size and cognition in food webs.

    PubMed

    Edmunds, Nicholas B; Laberge, Frédéric; McCann, Kevin S

    2016-08-01

    Predators tend to be large and mobile, enabling them to forage in spatially distinct food web compartments (e.g. littoral and pelagic aquatic macrohabitats). This feature can stabilise ecosystems when predators are capable of rapid behavioural response to changing resource conditions in distinct habitat compartments. However, what provides this ability to respond behaviourally has not been quantified. We hypothesised that predators require increased cognitive abilities to occupy their position in a food web, which puts pressure to increase brain size. Consistent with food web theory, we found that fish relative brain size increased with increased ability to forage across macrohabitats and increased relative trophic positions in a lacustrine food web, indicating that larger brains may afford the cognitive capacity to exploit various habitats flexibly, thus contributing to the stability of whole food webs.

  2. A critique of comparative studies of brain size

    PubMed Central

    Healy, Susan D; Rowe, Candy

    2006-01-01

    In recent years, there have been over 50 comparative analyses carried out in which social or ecological variables have been used to explain variation in whole brain size, or a part thereof, in a range of vertebrate species. Here, we review this body of work, pointing out that there are a number of substantial problems with some of the assumptions that underpin the hypotheses (e.g. what brain size means), with the data collection and with the ways in which the data are combined in the analyses. These problems are particularly apparent in those analyses in which attempts are made to correlate complex behaviour with parts of the brain that carry out multiple functions. We conclude that now is the time to substantiate these results with data from experimental manipulations. PMID:17476764

  3. New Nerve Cells for the Adult Brain.

    ERIC Educational Resources Information Center

    Kempermann, Gerd; Gage, Fred H.

    1999-01-01

    Contrary to dogma, the human brain does produce new nerve cells in adulthood. The mature human brain spawns neurons routinely in the hippocampus, an area important to memory and learning. This research can make it possible to ease any number of disorders involving neurological damage and death. (CCM)

  4. Spatiotemporal relationship between adult census size and genetic population size across a wide population size gradient.

    PubMed

    Bernos, Thaїs A; Fraser, Dylan J

    2016-09-01

    Adult census population size (N) and effective number of breeders (Nb ) are highly relevant for designing effective conservation strategies. Both parameters are often challenging to quantify, however, making it of interest to determine whether one parameter can be generalized from the other. Yet, the spatiotemporal relationship between N and Nb has not been well characterized empirically in many taxa. We analysed this relationship for 5-7 consecutive years in twelve brook trout populations varying greatly in N (49-10032) and Nb (3-567) and identified major environmental variables affecting the two parameters. N or habitat size alone explained 47-57% of the variance in Nb , and Nb was strongly correlated with effective population size. The ratio Nb /N ranged from 0.01 to 0.45 and increased at small N or following an annual decrease in N, suggesting density-dependent constraints on Nb . We found no evidence for a consistent, directional difference between variability in Nb and/or Nb /N among small and large populations; however, small populations had more varying temporal variability in Nb /N ratios than large populations. Finally, Nb and Nb /N were 2.5- and 2.3-fold more variable among populations than temporally within populations. Our results demonstrate a clear linkage between demographic and evolutionary parameters, suggesting that Nb could be used to approximate N (or vice versa) in natural populations. Nevertheless, using one variable to infer the other to monitor trends within populations is less recommended, perhaps even less so in small populations given their less predictable Nb vs. N dynamics. PMID:27483203

  5. [Generation of new nerve cells in the adult human brain].

    PubMed

    Poulsen, Frantz Rom; Meyer, Morten; Rasmussen, Jens Zimmer

    2003-03-31

    Generation of new nerve cells (neurogenesis) is normally considered to be limited to the fetal and early postnatal period. Thus, damaged nerve cells are not expected to be replaced by generation of new cells. The brain is, however, more plastic than previously assumed. This also includes neurogenesis in the adult human brain. In particular two brain regions show continuous division of neural stem and progenitor cells generating neurons and glial cells, namely the subgranular zone of the dentate gyrus and the subventricular zones of the lateral ventricles. From the latter region newly generated neuroblasts (immature nerve cells) migrate toward the olfactory bulb where they differentiate into neurons. In the dentate gyrus the newly generated neurons become functionally integrated in the granule cell layer, where they are believed to be of importance to learning and memory. It is at present not known whether neurogenesis in the adult human brain can be manipulated for specific repair after brain damage.

  6. Brain dynamics of meal size selection in humans.

    PubMed

    Toepel, Ulrike; Bielser, Marie-Laure; Forde, Ciaran; Martin, Nathalie; Voirin, Alexandre; le Coutre, Johannes; Murray, Micah M; Hudry, Julie

    2015-06-01

    Although neuroimaging research has evidenced specific responses to visual food stimuli based on their nutritional quality (e.g., energy density, fat content), brain processes underlying portion size selection remain largely unexplored. We identified spatio-temporal brain dynamics in response to meal images varying in portion size during a task of ideal portion selection for prospective lunch intake and expected satiety. Brain responses to meal portions judged by the participants as 'too small', 'ideal' and 'too big' were measured by means of electro-encephalographic (EEG) recordings in 21 normal-weight women. During an early stage of meal viewing (105-145 ms), data showed an incremental increase of the head-surface global electric field strength (quantified via global field power; GFP) as portion judgments ranged from 'too small' to 'too big'. Estimations of neural source activity revealed that brain regions underlying this effect were located in the insula, middle frontal gyrus and middle temporal gyrus, and are similar to those reported in previous studies investigating responses to changes in food nutritional content. In contrast, during a later stage (230-270 ms), GFP was maximal for the 'ideal' relative to the 'non-ideal' portion sizes. Greater neural source activity to 'ideal' vs. 'non-ideal' portion sizes was observed in the inferior parietal lobule, superior temporal gyrus and mid-posterior cingulate gyrus. Collectively, our results provide evidence that several brain regions involved in attention and adaptive behavior track 'ideal' meal portion sizes as early as 230 ms during visual encounter. That is, responses do not show an increase paralleling the amount of food viewed (and, in extension, the amount of reward), but are shaped by regulatory mechanisms. PMID:25812716

  7. Brain dynamics of meal size selection in humans.

    PubMed

    Toepel, Ulrike; Bielser, Marie-Laure; Forde, Ciaran; Martin, Nathalie; Voirin, Alexandre; le Coutre, Johannes; Murray, Micah M; Hudry, Julie

    2015-06-01

    Although neuroimaging research has evidenced specific responses to visual food stimuli based on their nutritional quality (e.g., energy density, fat content), brain processes underlying portion size selection remain largely unexplored. We identified spatio-temporal brain dynamics in response to meal images varying in portion size during a task of ideal portion selection for prospective lunch intake and expected satiety. Brain responses to meal portions judged by the participants as 'too small', 'ideal' and 'too big' were measured by means of electro-encephalographic (EEG) recordings in 21 normal-weight women. During an early stage of meal viewing (105-145 ms), data showed an incremental increase of the head-surface global electric field strength (quantified via global field power; GFP) as portion judgments ranged from 'too small' to 'too big'. Estimations of neural source activity revealed that brain regions underlying this effect were located in the insula, middle frontal gyrus and middle temporal gyrus, and are similar to those reported in previous studies investigating responses to changes in food nutritional content. In contrast, during a later stage (230-270 ms), GFP was maximal for the 'ideal' relative to the 'non-ideal' portion sizes. Greater neural source activity to 'ideal' vs. 'non-ideal' portion sizes was observed in the inferior parietal lobule, superior temporal gyrus and mid-posterior cingulate gyrus. Collectively, our results provide evidence that several brain regions involved in attention and adaptive behavior track 'ideal' meal portion sizes as early as 230 ms during visual encounter. That is, responses do not show an increase paralleling the amount of food viewed (and, in extension, the amount of reward), but are shaped by regulatory mechanisms.

  8. Brain size as a driver of avian escape strategy

    PubMed Central

    Samia, Diogo S. M.; Pape Møller, Anders; Blumstein, Daniel T.

    2015-01-01

    After detecting an approaching predator, animals make a decision when to flee. Prey will initiate flight soon after detecting a predator so as to minimize attentional costs related to on-going monitoring of the whereabouts of the predator. Such costs may compete with foraging and other maintenance activities and hence be larger than the costs of immediate flight. The drivers of interspecific variation in escape strategy are poorly known. Here we investigated the morphological, life history and natural history traits that correlate with variation in avian escape strategy across a sample of 96 species of birds. Brain mass, body size, habitat structure and group size were the main predictors of escape strategy. The direction of the effect of these traits was consistent with selection for a reduction of monitoring costs. Therefore, attentional costs depend on relative brain size, which determines the ability to monitor the whereabouts of potential predators and the difficulty of this task as reflected by habitat and social complexity. Thus brain size, and the cognitive functions associated with it, constitute a general framework for explaining the effects of body size, habitat structure and sociality identified as determinants of avian escape strategy. PMID:26139474

  9. Histomorphological Phenotyping of the Adult Mouse Brain.

    PubMed

    Mikhaleva, Anna; Kannan, Meghna; Wagner, Christel; Yalcin, Binnaz

    2016-01-01

    This article describes a series of standard operating procedures for morphological phenotyping of the mouse brain using basic histology. Many histological studies of the mouse brain use qualitative approaches based on what the human eye can detect. Consequently, some phenotypic information may be missed. Here we describe a quantitative approach for the assessment of brain morphology that is simple and robust. A total of 78 measurements are made throughout the brain at specific and well-defined regions, including the cortex, the hippocampus, and the cerebellum. Experimental design and timeline considerations, including strain background effects, the importance of sectioning quality, measurement variability, and efforts to correct human errors are discussed. © 2016 by John Wiley & Sons, Inc. PMID:27584555

  10. Manipulation complexity in primates coevolved with brain size and terrestriality

    PubMed Central

    Heldstab, Sandra A.; Kosonen, Zaida K.; Koski, Sonja E.; Burkart, Judith M.; van Schaik, Carel P.; Isler, Karin

    2016-01-01

    Humans occupy by far the most complex foraging niche of all mammals, built around sophisticated technology, and at the same time exhibit unusually large brains. To examine the evolutionary processes underlying these features, we investigated how manipulation complexity is related to brain size, cognitive test performance, terrestriality, and diet quality in a sample of 36 non-human primate species. We categorized manipulation bouts in food-related contexts into unimanual and bimanual actions, and asynchronous or synchronous hand and finger use, and established levels of manipulative complexity using Guttman scaling. Manipulation categories followed a cumulative ranking. They were particularly high in species that use cognitively challenging food acquisition techniques, such as extractive foraging and tool use. Manipulation complexity was also consistently positively correlated with brain size and cognitive test performance. Terrestriality had a positive effect on this relationship, but diet quality did not affect it. Unlike a previous study on carnivores, we found that, among primates, brain size and complex manipulations to acquire food underwent correlated evolution, which may have been influenced by terrestriality. Accordingly, our results support the idea of an evolutionary feedback loop between manipulation complexity and cognition in the human lineage, which may have been enhanced by increasingly terrestrial habits. PMID:27075921

  11. Adult mouse brain gene expression patterns bear an embryologic imprint.

    PubMed

    Zapala, Matthew A; Hovatta, Iiris; Ellison, Julie A; Wodicka, Lisa; Del Rio, Jo A; Tennant, Richard; Tynan, Wendy; Broide, Ron S; Helton, Rob; Stoveken, Barbara S; Winrow, Christopher; Lockhart, Daniel J; Reilly, John F; Young, Warren G; Bloom, Floyd E; Lockhart, David J; Barlow, Carrolee

    2005-07-19

    The current model to explain the organization of the mammalian nervous system is based on studies of anatomy, embryology, and evolution. To further investigate the molecular organization of the adult mammalian brain, we have built a gene expression-based brain map. We measured gene expression patterns for 24 neural tissues covering the mouse central nervous system and found, surprisingly, that the adult brain bears a transcriptional "imprint" consistent with both embryological origins and classic evolutionary relationships. Embryonic cellular position along the anterior-posterior axis of the neural tube was shown to be closely associated with, and possibly a determinant of, the gene expression patterns in adult structures. We also observed a significant number of embryonic patterning and homeobox genes with region-specific expression in the adult nervous system. The relationships between global expression patterns for different anatomical regions and the nature of the observed region-specific genes suggest that the adult brain retains a degree of overall gene expression established during embryogenesis that is important for regional specificity and the functional relationships between regions in the adult. The complete collection of extensively annotated gene expression data along with data mining and visualization tools have been made available on a publicly accessible web site (www.barlow-lockhart-brainmapnimhgrant.org).

  12. The effects of vitamin D on brain development and adult brain function.

    PubMed

    Kesby, James P; Eyles, Darryl W; Burne, Thomas H J; McGrath, John J

    2011-12-01

    A role for vitamin D in brain development and function has been gaining support over the last decade. Multiple lines of evidence suggest that this vitamin is actually a neuroactive steroid that acts on brain development, leading to alterations in brain neurochemistry and adult brain function. Early deficiencies have been linked with neuropsychiatric disorders, such as schizophrenia, and adult deficiencies have been associated with a host of adverse brain outcomes, including Parkinson's disease, Alzheimer's disease, depression and cognitive decline. This review summarises the current state of research on the actions of vitamin D in the brain and the consequences of deficiencies in this vitamin. Furthermore, we discuss specific implications of vitamin D status on the neurotransmitter, dopamine. PMID:21664231

  13. Brain size and brain organization of the whale shark, Rhincodon typus, using magnetic resonance imaging.

    PubMed

    Yopak, Kara E; Frank, Lawrence R

    2009-01-01

    Very little is known about the brain organization of the suction filter feeder, Rhincodon typus, and how it compares to other orectolobiforms in light of its specialization as a plankton-feeder. Brain size and overall brain organization was assessed in two specimens of R. typus in relation to both phylogeny and ecology, using magnetic resonance imaging (MRI). In comparison to over 60 other chondrichthyan species, R. typus demonstrated a relatively small brain for its body size (expressed in terms of encephalization quotients and residuals), similar to the lamniforms Carcharodon carcharias, Cetorhinus maximus, and Carcharias taurus. R. typus possessed a relatively small telencephalon with some development of the dorsal pallium, which was suggestive of moderate social behavior, in addition to a relatively large diencephalon and a relatively reduced mesencephalon. The most notable characteristic of the brain of Rhincodon was a large and highly foliated cerebellum, one of the largest cerebellums within the chondrichthyan clade. Early development of the brain was qualitatively assessed using an in situ MRI scan of the brain and chondrocranium of a neonate specimen of R. typus. There was evidence that folding of the cerebellar corpus appeared in early development, although the depth and number of folds might vary ontogenetically in this species. Hierarchical cluster analysis and multidimensional scaling ordinations showed evidence of convergent evolution with the basking shark, Cetorhinus maximus, another large-bodied filter feeding elasmobranch, supporting the claim that organization of the brain is more similar in species with analogous but independently evolved lifestyles than those that share taxonomic classification.

  14. Expansion of Multipotent Stem Cells from the Adult Human Brain

    PubMed Central

    Murrell, Wayne; Palmero, Emily; Bianco, John; Stangeland, Biljana; Joel, Mrinal; Paulson, Linda; Thiede, Bernd; Grieg, Zanina; Ramsnes, Ingunn; Skjellegrind, Håvard K.; Nygård, Ståle; Brandal, Petter; Sandberg, Cecilie; Vik-Mo, Einar; Palmero, Sheryl; Langmoen, Iver A.

    2013-01-01

    The discovery of stem cells in the adult human brain has revealed new possible scenarios for treatment of the sick or injured brain. Both clinical use of and preclinical research on human adult neural stem cells have, however, been seriously hampered by the fact that it has been impossible to passage these cells more than a very few times and with little expansion of cell numbers. Having explored a number of alternative culturing conditions we here present an efficient method for the establishment and propagation of human brain stem cells from whatever brain tissue samples we have tried. We describe virtually unlimited expansion of an authentic stem cell phenotype. Pluripotency proteins Sox2 and Oct4 are expressed without artificial induction. For the first time multipotency of adult human brain-derived stem cells is demonstrated beyond tissue boundaries. We characterize these cells in detail in vitro including microarray and proteomic approaches. Whilst clarification of these cells’ behavior is ongoing, results so far portend well for the future repair of tissues by transplantation of an adult patient’s own-derived stem cells. PMID:23967194

  15. Extrahypophysial distribution of corticotropin as a function of brain size.

    PubMed Central

    Moldow, R; Yalow, R S

    1978-01-01

    Determination by radioimmunoassay of corticotropin in the brains of rats, rabbits, dogs, monkeys, and human beings reveals that the dimensions within which the hormone is found is about the same for each of these species but that the anatomical regions in which the hormone is found depends on brain size. Corticotropin is widely distributed in the brain of rats but is found only in the hypothalamic region of the primate brain. The patterns of immunoreactivity observed after Sephadex gel filtration confirm that the molecular forms of corticotropin found in extrahypophysial regions are similar to those in the pituitary of each species. These findings suggest that the mammalian pituitary is the sole site of synthesis of the hormone. The observation of persistence of corticotropin in the brains of commerically hypophysectomized rats has been interpreted by others as suggesting diencephalic as well as pituitary origin for this peptide. However, our studies demonstrate that 8 weeks after hypophysectomy the rats we have received from commerical sources manifest stress-stimulated plasma corticotropin concentrations about 80% of that found in intact rats in spite of the fact that residual pituitary tissue was not found by visual inspection of the sella. Scrapings from the sella revealed a corticotropin content up to 5% that of the average rat pituitary. Images PMID:204943

  16. The brain and the braincase: a spatial analysis on the midsagittal profile in adult humans.

    PubMed

    Bruner, Emiliano; Amano, Hideki; de la Cuétara, José Manuel; Ogihara, Naomichi

    2015-09-01

    The spatial relationships between brain and braincase represent a major topic in surgery and evolutionary neuroanatomy. In paleoneurology, neurocranial landmarks are often used as references for brain areas. In this study, we analyze the variation and covariation of midsagittal brain and skull coordinates in a sample of adult modern humans in order to demonstrate spatial associations between hard and soft tissues. The correlation between parietal lobe size and parietal bone size is very low, and there is a marked individual variation. The distances between lobes and bones are partially influenced by the dimensions of the parietal lobes. The main pattern of morphological variability among individuals, associated with the size of the precuneus, apparently does not influence the position of the neurocranial sutures. Therefore, variations in precuneal size modify the distance between the paracentral lobule and bregma, and between the parietal lobe and lambda. Hence, the relative position of the cranial and cerebral landmarks can change as a function of the parietal dimensions. The slight correlation and covariation among these elements suggests a limited degree of spatial integration between soft and hard tissues. Therefore, although the brain influences the cranial size and shape during morphogenesis, the specific position of the cerebral components is sensitive to multiple effects and local factors, without a strict correspondence with the bone landmarks. This absence of correspondent change between brain and skull boundaries suggests caution when making inferences about the brain areas from the position of the cranial sutures. The fact that spatial relationships between cranial and brain areas may vary according to brain proportions must be considered in paleoneurology, when brain anatomy is inferred from cranial evidence.

  17. Dunbar's number: group size and brain physiology in humans reexamined.

    PubMed

    de Ruiter, Jan; Weston, Gavin; Lyon, Stephen M

    2011-01-01

    Popular academic ideas linking physiological adaptations to social behaviors are spreading disconcertingly into wider societal contexts. In this article, we note our skepticism with one particularly popular—in our view, problematic—supposed causal correlation between neocortex size and social group size. The resulting Dunbar's Number, as it has come to be called, has been statistically tested against observed group size in different primate species. Although there may be reason to doubt the Dunbar's Number hypothesis among nonhuman primate species, we restrict ourselves here to the application of such an explanatory hypothesis to human, culture-manipulating populations. Human information process management, we argue, cannot be understood as a simple product of brain physiology. Cross-cultural comparison of not only group size but also relationship-reckoning systems like kinship terminologies suggests that although neocortices are undoubtedly crucial to human behavior, they cannot be given such primacy in explaining complex group composition, formation, or management.

  18. Online social network size is reflected in human brain structure.

    PubMed

    Kanai, R; Bahrami, B; Roylance, R; Rees, G

    2012-04-01

    The increasing ubiquity of web-based social networking services is a striking feature of modern human society. The degree to which individuals participate in these networks varies substantially for reasons that are unclear. Here, we show a biological basis for such variability by demonstrating that quantitative variation in the number of friends an individual declares on a web-based social networking service reliably predicted grey matter density in the right superior temporal sulcus, left middle temporal gyrus and entorhinal cortex. Such regions have been previously implicated in social perception and associative memory, respectively. We further show that variability in the size of such online friendship networks was significantly correlated with the size of more intimate real-world social groups. However, the brain regions we identified were specifically associated with online social network size, whereas the grey matter density of the amygdala was correlated both with online and real-world social network sizes. Taken together, our findings demonstrate that the size of an individual's online social network is closely linked to focal brain structure implicated in social cognition. PMID:22012980

  19. Inflammation is detrimental for neurogenesis in adult brain

    NASA Astrophysics Data System (ADS)

    Ekdahl, Christine T.; Claasen, Jan-Hendrik; Bonde, Sara; Kokaia, Zaal; Lindvall, Olle

    2003-11-01

    New hippocampal neurons are continuously generated in the adult brain. Here, we demonstrate that lipopolysaccharide-induced inflammation, which gives rise to microglia activation in the area where the new neurons are born, strongly impairs basal hippocampal neurogenesis in rats. The increased neurogenesis triggered by a brain insult is also attenuated if it is associated with microglia activation caused by tissue damage or lipopolysaccharide infusion. The impaired neurogenesis in inflammation is restored by systemic administration of minocycline, which inhibits microglia activation. Our data raise the possibility that suppression of hippocampal neurogenesis by activated microglia contributes to cognitive dysfunction in aging, dementia, epilepsy, and other conditions leading to brain inflammation.

  20. Brain abscess caused by Citrobacter koseri infection in an adult.

    PubMed

    Liu, Heng-Wei; Chang, Chih-Ju; Hsieh, Cheng-Ta

    2015-04-01

    Citrobacter koseri is a gram-negative bacillus that causes mostly meningitis and brain abscesses in neonates and infants. However, brain abscess caused by Citrobacter koseri infection in an adult is extremely rare, and only 2 cases have been described. Here, we reported a 73-year-old male presenting with a 3-week headache. A history of diabetes mellitus was noted. The images revealed a brain abscess in the left frontal lobe and pus culture confirmed the growth of Citrobacter koseri. The clinical symptoms improved completely postoperatively.

  1. Size & Flow: Adult Education Issues in the Senate Immigration Bill

    ERIC Educational Resources Information Center

    Murphy, Garrett; Spangenberg, Gail

    2014-01-01

    In this essay Garrett Murphy and Gail Spangenberg report on the need for understanding better than in the past, the number of undocumented immigrants likely to need adult education services under provisions of Senate Immigration Bill S.744. The essay looks at why the issues of "size and flow" are important for planners, providers, and…

  2. Abnormal brain structure in adults with Van der Woude syndrome.

    PubMed

    Nopoulos, P; Richman, L; Andreasen, N C; Murray, J C; Schutte, B

    2007-06-01

    Van der Woude syndrome (VWS) is an autosomal dominant disorder manifested in cleft lip and/or palate and lip pits. Isolated clefts of the lip and/or palate (ICLP) have both genotype and phenotype overlap with VWS. Subjects with ICLP have abnormalities in brain structure and function. Given the similarities between VWS and ICLP, the current study was designed to evaluate the pattern of brain structure of adults with VWS. Fourteen adults with VWS were compared to age- and gender-matched healthy controls. Brain structure was evaluated using magnetic resonance imaging. All subjects with VWS had enlarged volumes of the anterior regions of the cerebrum. Men with VWS had reduced volumes of the posterior cerebrum. Anterior cerebrum volume was negatively correlated with intelligent quotient in the subjects with VWS indicating that the enlargement of this brain region was 'pathologic.' The pattern of brain structure in VWS is nearly identical to those seen in ICLP. In addition, men are affected more severely. Pathologic enlargement of the tissue and a gender effect with men affected more severely are common features of neurodevelopmental disorders supporting the notion that the brain structure of VWS and ICLP may be because of abnormal brain development. PMID:17539900

  3. Cranial Capacity: New Caucasian Data and Comments on Rushton's Claimed Mongoloid-Caucasoid Brain-Size Differences.

    ERIC Educational Resources Information Center

    Reed, T. Edward; Jensen, Arthur R.

    1993-01-01

    Data are presented on body weight and cranial capacity for 211 young adult male Caucasians (postsecondary students). The data do not support Rushton's claim for a greater weight-adjusted cranial capacity of Mongoloid males. Speed and efficiency of cortical information processing may be more important for intelligence than brain size. (SLD)

  4. Birth Size and Brain Function 75 Years Later

    PubMed Central

    Muller, Majon; Sigurdsson, Sigurdur; Kjartansson, Olafur; Jonsson, Palmi V.; Garcia, Melissa; von Bonsdorff, Mikaela B.; Gunnarsdottir, Ingibjorg; Thorsdottir, Inga; Harris, Tamara B.; van Buchem, Mark; Gudnason, Vilmundur

    2014-01-01

    BACKGROUND: There are several lines of evidence pointing to fetal and other early origins of diseases of the aging brain, but there are no data directly addressing the hypotheses in an older population. We investigated the association of fetal size to late-age measures of brain structure and function in a large cohort of older men and women and explored the modifying effect of education on these associations. METHODS: Within the AGES (Age Gene/Environment Susceptibility)-Reykjavik population-based cohort (born between 1907 and 1935), archived birth records were abstracted for 1254 men and women who ∼75 years later underwent an examination that included brain MRI and extensive cognitive assessment. RESULTS: Adjustment for intracranial volume, demographic and medical history characteristics, and lower Ponderal index at birth (per kg/m3), an indicator of third-trimester fetal wasting, was significantly associated with smaller volumes of total brain and white matter; βs (95% confidence intervals) were −1.0 (−1.9 to −0.0) and −0.5 (−1.0 to −0.0) mL. Furthermore, lower Ponderal index was associated with slower processing speed and reduced executive functioning but only in those with low education (β [95% confidence interval]: −0.136 [−0.235 to −0.036] and −0.077 [−0.153 to −0.001]). CONCLUSIONS: This first study of its kind provides clinical measures suggesting that smaller birth size, as an indicator of a suboptimal intrauterine environment, is associated with late-life alterations in brain tissue volume and function. In addition, it shows that the effects of a suboptimal intrauterine environment on late-life cognitive function were present only in those with lower educational levels. PMID:25180277

  5. Human-specific hypomethylation of CENPJ, a key brain size regulator.

    PubMed

    Shi, Lei; Lin, Qiang; Su, Bing

    2014-03-01

    Both the enlarged brain and concurrent highly developed cognitive skills are often seen as distinctive characteristics that set humans apart from other primates. Despite this obvious differentiation, the genetic mechanisms that underlie such human-specific traits are not clearly understood. In particular, whether epigenetic regulations may play a key role in human brain evolution remain elusive. In this study, we used bisulfite sequencing to compare the methylation patterns of four known genes that regulate brain size (ASPM, CDK5RAP2, CENPJ, and MCPH1) in the prefrontal cortex among several primate species spanning the major lineages of primates (i.e., humans, great apes, lesser apes, and Old World monkeys). The results showed a human-specific hypomethylation in the 5' UTR of CENPJ in the brain, where methylation levels among humans are only about one-third of those found among nonhuman primates. Similar methylation patterns were also detected in liver, kidney, and heart tissues, although the between-species differences were much less pronounced than those in the brain. Further in vitro methylation assays indicated that the methylation status of the CENPJ promoter could influence its expression. We also detected a large difference in CENPJ expression in the human and nonhuman primate brains of both adult individuals and throughout the major stages of fetal brain development. The hypomethylation and comparatively high expression of CENPJ in the central nervous system of humans suggest that a human-specific--and likely heritable--epigenetic modification likely occurred during human evolution, potentially leading to a much larger neural progenitor pool during human brain development, which may have eventually contributed to the dramatically enlarged brain and highly developed cognitive abilities associated with humans. PMID:24288161

  6. Human-specific hypomethylation of CENPJ, a key brain size regulator.

    PubMed

    Shi, Lei; Lin, Qiang; Su, Bing

    2014-03-01

    Both the enlarged brain and concurrent highly developed cognitive skills are often seen as distinctive characteristics that set humans apart from other primates. Despite this obvious differentiation, the genetic mechanisms that underlie such human-specific traits are not clearly understood. In particular, whether epigenetic regulations may play a key role in human brain evolution remain elusive. In this study, we used bisulfite sequencing to compare the methylation patterns of four known genes that regulate brain size (ASPM, CDK5RAP2, CENPJ, and MCPH1) in the prefrontal cortex among several primate species spanning the major lineages of primates (i.e., humans, great apes, lesser apes, and Old World monkeys). The results showed a human-specific hypomethylation in the 5' UTR of CENPJ in the brain, where methylation levels among humans are only about one-third of those found among nonhuman primates. Similar methylation patterns were also detected in liver, kidney, and heart tissues, although the between-species differences were much less pronounced than those in the brain. Further in vitro methylation assays indicated that the methylation status of the CENPJ promoter could influence its expression. We also detected a large difference in CENPJ expression in the human and nonhuman primate brains of both adult individuals and throughout the major stages of fetal brain development. The hypomethylation and comparatively high expression of CENPJ in the central nervous system of humans suggest that a human-specific--and likely heritable--epigenetic modification likely occurred during human evolution, potentially leading to a much larger neural progenitor pool during human brain development, which may have eventually contributed to the dramatically enlarged brain and highly developed cognitive abilities associated with humans.

  7. Narrative Skills Following Traumatic Brain Injury in Children and Adults.

    ERIC Educational Resources Information Center

    Biddle, Kathleen R.; And Others

    1996-01-01

    This study used dependency analysis to document and describe the narrative discourse impairments of 10 children (mean age 12) and 10 adults (mean age 35) with traumatic brain injury (TBI), and matched controls. Individuals with TBI were significantly more disfluent than controls and their narrative performance required a significant listener…

  8. Bilateral Brain Regions Associated with Naming in Older Adults

    ERIC Educational Resources Information Center

    Obler, Loraine K.; Rykhlevskaia, Elena; Schnyer, David; Clark-Cotton, Manuella R.; Spiro, Avron, III; Hyun, JungMoon; Kim, Dae-Shik; Goral, Mira; Albert, Martin L.

    2010-01-01

    To determine structural brain correlates of naming abilities in older adults, we tested 24 individuals aged 56-79 on two confrontation-naming tests (the Boston Naming Test (BNT) and the Action Naming Test (ANT)), then collected from these individuals structural Magnetic-Resonance Imaging (MRI) and Diffusion Tensor Imaging (DTI) data. Overall,…

  9. Neuronal replacement from endogenous precursors in the adult brain after stroke.

    PubMed

    Arvidsson, Andreas; Collin, Tove; Kirik, Deniz; Kokaia, Zaal; Lindvall, Olle

    2002-09-01

    In the adult brain, new neurons are continuously generated in the subventricular zone and dentate gyrus, but it is unknown whether these neurons can replace those lost following damage or disease. Here we show that stroke, caused by transient middle cerebral artery occlusion in adult rats, leads to a marked increase of cell proliferation in the subventricular zone. Stroke-generated new neurons, as well as neuroblasts probably already formed before the insult, migrate into the severely damaged area of the striatum, where they express markers of developing and mature, striatal medium-sized spiny neurons. Thus, stroke induces differentiation of new neurons into the phenotype of most of the neurons destroyed by the ischemic lesion. Here we show that the adult brain has the capacity for self-repair after insults causing extensive neuronal death. If the new neurons are functional and their formation can be stimulated, a novel therapeutic strategy might be developed for stroke in humans. PMID:12161747

  10. Brain size is correlated with endangerment status in mammals.

    PubMed

    Abelson, Eric S

    2016-02-24

    Increases in relative encephalization (RE), brain size after controlling for body size, comes at a great metabolic cost and is correlated with a host of cognitive traits, from the ability to count objects to higher rates of innovation. Despite many studies examining the implications and trade-offs accompanying increased RE, the relationship between mammalian extinction risk and RE is unknown. I examine whether mammals with larger levels of RE are more or less likely to be at risk of endangerment than less-encephalized species. I find that extant species with large levels of encephalization are at greater risk of endangerment, with this effect being strongest in species with small body sizes. These results suggest that RE could be a valuable asset in estimating extinction vulnerability. Additionally, these findings suggest that the cost-benefit trade-off of RE is different in large-bodied species when compared with small-bodied species. PMID:26888034

  11. Developmental Vitamin D3 deficiency alters the adult rat brain.

    PubMed

    Féron, F; Burne, T H J; Brown, J; Smith, E; McGrath, J J; Mackay-Sim, A; Eyles, D W

    2005-03-15

    There is growing evidence that Vitamin D(3) (1,25-dihydroxyvitamin D(3)) is involved in brain development. We have recently shown that the brains of newborn rats from Vitamin D(3) deficient dams were larger than controls, had increased cell proliferation, larger lateral ventricles, and reduced cortical thickness. Brains from these animals also had reduced expression of nerve growth factor (NGF) and glial cell line-derived neurotrophic factor. The aim of the current study was to examine if there were any permanent outcomes into adulthood when the offspring of Vitamin D(3) deficient dams were restored to a normal diet. The brains of adult rats were examined at 10 weeks of age after Vitamin D(3) deficiency until birth or weaning. Compared to controls animals that were exposed to transient early Vitamin D(3) deficiency had larger lateral ventricles, reduced NGF protein content, and reduced expression of a number genes involved in neuronal structure, i.e. neurofilament or MAP-2 or neurotransmission, i.e. GABA-A(alpha4). We conclude that transient early life hypovitaminosis D(3) not only disrupts brain development but leads to persistent changes in the adult brain. In light of the high incidence of hypovitaminosis D(3) in women of child-bearing age, the public health implications of these findings warrant attention. PMID:15763180

  12. Pedophilic brain potential responses to adult erotic stimuli.

    PubMed

    Knott, Verner; Impey, Danielle; Fisher, Derek; Delpero, Emily; Fedoroff, Paul

    2016-02-01

    Cognitive mechanisms associated with the relative lack of sexual interest in adults by pedophiles are poorly understood and may benefit from investigations examining how the brain processes adult erotic stimuli. The current study used event-related brain potentials (ERP) to investigate the time course of the explicit processing of erotic, emotional, and neutral pictures in 22 pedophilic patients and 22 healthy controls. Consistent with previous studies, early latency anterior ERP components were highly selective for erotic pictures. Although the ERPs elicited by emotional stimuli were similar in patients and controls, an early frontal positive (P2) component starting as early as 185 ms was significantly attenuated and slow to onset in pedophilia, and correlated with a clinical measure of cognitive distortions. Failure of rapid attentional capture by erotic stimuli suggests a relative reduction in early processing in pedophilic patients which may be associated with relatively diminished sexual interest in adults. PMID:26683083

  13. [Endocrine functions of the brain in adult and developing mammals].

    PubMed

    Ugriumov, M V

    2009-01-01

    The main prerequisite for organism's viability is the maintenance of the internal environment despite changes in the external environment, which is provided by the neuroendocrine control system. The key unit in this system is hypothalamus exerting endocrine effects on certain peripheral organs and anterior pituitary. Physiologically active substances of neuronal origin enter blood vessels in the neurohemal parts of hypothalamus where no blood-brain barrier exists. In other parts of the adult brain, the arrival of physiologically active substances is blocked by the blood-brain barrier. According to the generally accepted concept, the neuroendocrine system formation in ontogeny starts with the maturation of peripheral endocrine glands, which initially function autonomously and then are controlled by the anterior pituitary. The brain is engaged in neuroendocrine control after its maturation completes, which results in a closed control system typical of adult mammals. Since neurons start to secrete physiologically active substances soon after their formation and long before interneuronal connections are formed, these cells are thought to have an effect on brain development as inducers. Considering that there is no blood-brain barrier during this period, we proposed the hypothesis that the developing brain functions as a multipotent endocrine organ. This means that tens of physiologically active substances arrive from the brain to the systemic circulation and have an endocrine effect on the whole body development. Dopamine, serotonin, and gonadotropin-releasing hormone were selected as marker physiologically active substances of cerebral origin to test this hypothesis. In adult animals, they act as neurotransmitters or neuromodulators transmitting information from neuron to neuron as well as neurohormones arriving from the hypothalamus with portal blood to the anterior pituitary. Perinatal rats--before the blood-brain barrier is formed--proved to have equally high

  14. Brain size and brain organization of the whale shark, Rhincodon typus, using magnetic resonance imaging.

    PubMed

    Yopak, Kara E; Frank, Lawrence R

    2009-01-01

    Very little is known about the brain organization of the suction filter feeder, Rhincodon typus, and how it compares to other orectolobiforms in light of its specialization as a plankton-feeder. Brain size and overall brain organization was assessed in two specimens of R. typus in relation to both phylogeny and ecology, using magnetic resonance imaging (MRI). In comparison to over 60 other chondrichthyan species, R. typus demonstrated a relatively small brain for its body size (expressed in terms of encephalization quotients and residuals), similar to the lamniforms Carcharodon carcharias, Cetorhinus maximus, and Carcharias taurus. R. typus possessed a relatively small telencephalon with some development of the dorsal pallium, which was suggestive of moderate social behavior, in addition to a relatively large diencephalon and a relatively reduced mesencephalon. The most notable characteristic of the brain of Rhincodon was a large and highly foliated cerebellum, one of the largest cerebellums within the chondrichthyan clade. Early development of the brain was qualitatively assessed using an in situ MRI scan of the brain and chondrocranium of a neonate specimen of R. typus. There was evidence that folding of the cerebellar corpus appeared in early development, although the depth and number of folds might vary ontogenetically in this species. Hierarchical cluster analysis and multidimensional scaling ordinations showed evidence of convergent evolution with the basking shark, Cetorhinus maximus, another large-bodied filter feeding elasmobranch, supporting the claim that organization of the brain is more similar in species with analogous but independently evolved lifestyles than those that share taxonomic classification. PMID:19729899

  15. Measurement of neuromagnetic brain function in pre-school children with custom sized MEG.

    PubMed

    Tesan, Graciela; Johnson, Blake W; Reid, Melanie; Thornton, Rosalind; Crain, Stephen

    2010-01-01

    Magnetoencephalography is a technique that detects magnetic fields associated with cortical activity [1]. The electrophysiological activity of the brain generates electric fields - that can be recorded using electroencephalography (EEG)- and their concomitant magnetic fields - detected by MEG. MEG signals are detected by specialized sensors known as superconducting quantum interference devices (SQUIDs). Superconducting sensors require cooling with liquid helium at -270 degrees C. They are contained inside a vacumm-insulated helmet called a dewar, which is filled with liquid. SQUIDS are placed in fixed positions inside the helmet dewar in the helium coolant, and a subject's head is placed inside the helmet dewar for MEG measurements. The helmet dewar must be sized to satisfy opposing constraints. Clearly, it must be large enough to fit most or all of the heads in the population that will be studied. However, the helmet must also be small enough to keep most of the SQUID sensors within range of the tiny cerebral fields that they are to measure. Conventional whole-head MEG systems are designed to accommodate more than 90% of adult heads. However adult systems are not well suited for measuring brain function in pre-school chidren whose heads have a radius several cm smaller than adults. The KIT-Macquarie Brain Research Laboratory at Macquarie University uses a MEG system custom sized to fit the heads of pre-school children. This child system has 64 first-order axial gradiometers with a 50 mm baseline[2] and is contained inside a magnetically-shielded room (MSR) together with a conventional adult-sized MEG system [3,4]. There are three main advantages of the customized helmet dewar for studying children. First, the smaller radius of the sensor configuration brings the SQUID sensors into range of the neuromagnetic signals of children's heads. Second, the smaller helmet allows full insertion of a child's head into the dewar. Full insertion is prevented in adult dewar

  16. Variation in avian brain shape: relationship with size and orbital shape

    PubMed Central

    Kawabe, Soichiro; Shimokawa, Tetsuya; Miki, Hitoshi; Matsuda, Seiji; Endo, Hideki

    2013-01-01

    There is wide variation in brain shape among birds. Differences in brain dimensions reflect species-specific sensory capacities and behavioral repertoires that are shaped by environmental and biological factors during evolution. Most previous studies aimed at defining factors impacting brain shape have used volumetric or linear measurements. However, few have explored the quantitative indices of three-dimensional (3D) brain geometry that are absolutely imperative to understanding avian evolutionary history. This study aimed: (i) to explore the relationship between brain shape and overall brain size; and (ii) to assess the relationship between brain shape and orbital shape. Avian brain endocasts were reconstructed from computed tomography images and analyzed using 3D geometric morphometrics. Principal component analysis revealed dominant regional variations in avian brain shape and shape correlations between the telencephalon and cerebellum, between the cerebellum and myelencephalon, and between the diencephalon and optic tectum. Brain shape changes relative to total brain size were determined by multivariate regression analysis. Larger brain size was associated with a relatively slender telencephalon and differences in brain orientation. The correlation between brain shape and orbital shape was assessed by two-block partial least-squares analysis. Relatively round brains with a ventrally flexed brain base were associated with rounder orbits, while narrower brains with a flat brain base were associated with more elongated orbits. The shapes of functionally associated avian brain regions are correlated, and orbital size and shape are dominant factors influencing the overall shape of the avian brain. PMID:24020351

  17. Relationships between Gene Expression and Brain Wiring in the Adult Rodent Brain

    PubMed Central

    French, Leon; Pavlidis, Paul

    2011-01-01

    We studied the global relationship between gene expression and neuroanatomical connectivity in the adult rodent brain. We utilized a large data set of the rat brain “connectome” from the Brain Architecture Management System (942 brain regions and over 5000 connections) and used statistical approaches to relate the data to the gene expression signatures of 17,530 genes in 142 anatomical regions from the Allen Brain Atlas. Our analysis shows that adult gene expression signatures have a statistically significant relationship to connectivity. In particular, brain regions that have similar expression profiles tend to have similar connectivity profiles, and this effect is not entirely attributable to spatial correlations. In addition, brain regions which are connected have more similar expression patterns. Using a simple optimization approach, we identified a set of genes most correlated with neuroanatomical connectivity, and find that this set is enriched for genes involved in neuronal development and axon guidance. A number of the genes have been implicated in neurodevelopmental disorders such as autistic spectrum disorder. Our results have the potential to shed light on the role of gene expression patterns in influencing neuronal activity and connectivity, with potential applications to our understanding of brain disorders. Supplementary data are available at http://www.chibi.ubc.ca/ABAMS. PMID:21253556

  18. Pericytes control key neurovascular functions and neuronal phenotype in the adult brain and during brain aging

    PubMed Central

    Bell, Robert D.; Winkler, Ethan A.; Sagare, Abhay P.; Singh, Itender; LaRue, Barb; Deane, Rashid; Zlokovic, Berislav V.

    2010-01-01

    SUMMARY Pericytes play a key role in the development of cerebral microcirculation. The exact role of pericytes in the neurovascular unit in the adult brain and during brain aging remains, however, elusive. Using adult viable pericyte-deficient mice, we show that pericyte loss leads to brain vascular damage by two parallel pathways: (1) reduction in brain microcirculation causing diminished brain capillary perfusion, cerebral blood flow and cerebral blood flow responses to brain activation which ultimately mediates chronic perfusion stress and hypoxia, and (2) blood-brain barrier breakdown associated with brain accumulation of serum proteins and several vasculotoxic and/or neurotoxic macromolecules ultimately leading to secondary neuronal degenerative changes. We show that age-dependent vascular damage in pericyte-deficient mice precedes neuronal degenerative changes, learning and memory impairment and the neuroinflammatory response. Thus, pericytes control key neurovascular functions that are necessary for proper neuronal structure and function, and pericytes loss results in a progressive age-dependent vascular-mediated neurodegeneration. PMID:21040844

  19. Brain Size, IQ, and Racial-Group Differences: Evidence from Musculoskeletal Traits.

    ERIC Educational Resources Information Center

    Rushton, J. Philippe; Rushton, Elizabeth W.

    2003-01-01

    Correlated brain size differences with 37 musculoskeletal variables shown in evolutionary textbooks to change with brain size. Findings from a sample of more than 6,000 U.S. military personnel indicate that racial differences in brain size are securely established and are the most likely biological mediators of race differences in intelligence.…

  20. Life satisfaction in adult survivors of childhood brain tumors.

    PubMed

    Crom, Deborah B; Li, Zhenghong; Brinkman, Tara M; Hudson, Melissa M; Armstrong, Gregory T; Neglia, Joseph; Ness, Kirsten K

    2014-01-01

    Adult survivors of childhood brain tumors experience multiple, significant, lifelong deficits as a consequence of their malignancy and therapy. Current survivorship literature documents the substantial impact such impairments have on survivors' physical health and quality of life. Psychosocial reports detail educational, cognitive, and emotional limitations characterizing survivors as especially fragile, often incompetent, and unreliable in evaluating their circumstances. Anecdotal data suggest some survivors report life experiences similar to those of healthy controls. The aim of our investigation was to determine whether life satisfaction in adult survivors of childhood brain tumors differs from that of healthy controls and to identify potential predictors of life satisfaction in survivors. This cross-sectional study compared 78 brain tumor survivors with population-based matched controls. Chi-square tests, t tests, and linear regression models were used to investigate patterns of life satisfaction and identify potential correlates. Results indicated that life satisfaction of adult survivors of childhood brain tumors was similar to that of healthy controls. Survivors' general health expectations emerged as the primary correlate of life satisfaction. Understanding life satisfaction as an important variable will optimize the design of strategies to enhance participation in follow-up care, reduce suffering, and optimize quality of life in this vulnerable population.

  1. The influence of complex and threatening environments in early life on brain size and behaviour

    PubMed Central

    Neuberger, T.; Hirrlinger, A. M.; Braithwaite, V. A.

    2016-01-01

    The ways in which challenging environments during development shape the brain and behaviour are increasingly being addressed. To date, studies typically consider only single variables, but the real world is more complex. Many factors simultaneously affect the brain and behaviour, and whether these work independently or interact remains untested. To address this, zebrafish (Danio rerio) were reared in a two-by-two design in housing that varied in structural complexity and/or exposure to a stressor. Fish experiencing both complexity (enrichment objects changed over time) and mild stress (daily net chasing) exhibited enhanced learning and were less anxious when tested as juveniles (between 77 and 90 days). Adults tested (aged 1 year) were also less anxious even though fish were kept in standard housing after three months of age (i.e. no chasing or enrichment). Volumetric measures of the brain using magnetic resonance imaging (MRI) showed that complexity alone generated fish with a larger brain, but this increase in size was not seen in fish that experienced both complexity and chasing, or chasing alone. The results highlight the importance of looking at multiple variables simultaneously, and reveal differential effects of complexity and stressful experiences during development of the brain and behaviour. PMID:26817780

  2. A revised dosimetric model of the adult head and brain

    SciTech Connect

    Bouchet, L.G.; Bolch, W.E.; Weber, D.A.

    1996-06-01

    During the last decade, new radiopharmaceutical have been introduced for brain imaging. The marked differences of these tracers in tissue specificity within the brain and their increasing use for diagnostic studies support the need for a more anthropomorphic model of the human brain and head. Brain and head models developed in the past have been only simplistic representations of this anatomic region. For example, the brain within the phantom of MIRD Pamphlet No. 5 Revised is modeled simply as a single ellipsoid of tissue With no differentiation of its internal structures. To address this need, the MIRD Committee established a Task Group in 1992 to construct a more detailed brain model to include the cerebral cortex, the white matter, the cerebellum, the thalamus, the caudate nucleus, the lentiform nucleus, the cerebral spinal fluid, the lateral ventricles, and the third ventricle. This brain model has been included within a slightly modified version of the head model developed by Poston et al. in 1984. This model has been incorporated into the radiation transport code EGS4 so as to calculate photon and electron absorbed fractions in the energy range 10 keV to 4 MeV for each of thirteen sources in the brain. Furthermore, explicit positron transport have been considered, separating the contribution by the positron itself and its associated annihilations photons. No differences are found between the electron and positron absorbed fractions; however, for initial energies of positrons greater than {approximately}0.5 MeV, significant differences are found between absorbed fractions from explicit transport of annihilation photons and those from an assumed uniform distribution of 0.511-MeV photons. Subsequently, S values were calculated for a variety of beta-particle and positron emitters brain imaging agents. Moreover, pediatric head and brain dosimetric models are currently being developed based on this adult head model.

  3. Persistent Representation of Juvenile Experience in the Adult Songbird Brain

    PubMed Central

    Prather, JF; Peters, S; Nowicki, S; Mooney, R

    2010-01-01

    Juveniles sometimes learn behaviors that they cease to express as adults. Whether the adult brain retains a record of experiences associated with behaviors performed transiently during development remains unclear. We addressed this issue by studying neural representations of song in swamp sparrows, a species in which juveniles learn and practice many more songs than they retain in their adult vocal repertoire. We exposed juvenile swamp sparrows to a suite of tutor songs and confirmed that although many tutor songs were imitated during development, not all copied songs were retained into adulthood. We then recorded extracellularly in the sensorimotor nucleus HVC in anesthetized sparrows to assess neuronal responsiveness to songs in the adult repertoire, tutor songs, and novel songs. Individual HVC neurons almost always responded to songs in the adult repertoire and commonly responded even more strongly to a tutor song. Effective tutor songs were not simply those that were acoustically similar to songs in the adult repertoire. Moreover, the strength of tutor song responses was unrelated to the number of times that the bird sang copies of those songs in juvenile or adult life. Notably, several neurons responded most strongly to a tutor song performed only rarely and transiently during juvenile life, or even to a tutor song for which we could find no evidence of ever having been copied. Thus, HVC neurons representing songs in the adult repertoire also appear to retain a lasting record of certain tutor songs, including those imitated only transiently. PMID:20686001

  4. Immunological regulation of neurogenic niches in the adult brain

    PubMed Central

    Gonzalez-Perez, Oscar; Gutierrez-Fernandez, Fernando; Lopez-Virgen, Veronica; Collas-Aguilar, Jorge; Quinones-Hinojosa, Alfredo; Garcia-Verdugo, Jose M.

    2012-01-01

    In mammals, neurogenesis and oligodendrogenesis are germinal processes that occur in the adult brain throughout life. The subventricular (SVZ) and subgranular (SGZ) zones are the main neurogenic regions in adult brain. Therein, it resides a subpopulation of astrocytes that act as neural stem cells. Increasing evidence indicates that pro-inflammatory and other immunological mediators are important regulators of neural precursors into the SVZ and the SGZ. There are a number of inflammatory cytokines that regulate the function of neural stem cells. Some of the most studied include: interleukin-1, interleukin-6, tumor necrosis factor-alpha, insulin-like growth factor-1, growth-regulated oncogene-alpha, leukemia inhibitory factor, cardiotrophin-1, ciliary neurotrophic factor, interferon-gamma, monocyte chemotactic protein-1 and macrophage inflammatory protein-1alpha. This plethora of immunological mediators can control the migration, proliferation, quiescence, cell-fate choices and survival of neural stem cells and their progeny. Thus, systemic or local inflammatory processes represent important regulators of germinal niches in the adult brain. In this review, we summarized the current evidence regarding the effects of pro-inflammatory cytokines involved in the regulation of adult neural stem cells under in vitro and in vivo conditions. Additionally, we described the role of proinflammatory cytokines in neurodegenerative diseases and some therapeutical approaches for the immunomodulation of neural progenitor cells. PMID:22986164

  5. Prenatal Ethanol Exposure Increases Brain Cholesterol Content in Adult Rats

    PubMed Central

    Barceló-Coblijn, Gwendolyn; Wold, Loren E.; Ren, Jun; Murphy, Eric J.

    2013-01-01

    Fetal alcohol syndrome is the most severe expression of the fetal alcohol spectrum disorders (FASD). Although alterations in fetal and neonate brain fatty acid composition and cholesterol content is known to change in animal models of FASD, the persistence of these alterations into adulthood is unknown. To address this question, we determined the effect of prenatal ethanol exposure on individual phospholipid class fatty acid composition, individual phospholipid class mass, and cholesterol mass in brains from 25-week-old rats that were exposed to ethanol during gestation beginning at gestational day 2. While total phospholipid mass was unaffected, phosphatidylinositol and cardiolipin mass was decreased 14 and 43%, respectively. Exposure to prenatal ethanol modestly altered brain phospholipid fatty acid composition, and the most consistent change was a significant 1.1-fold increase in total PUFA, in the n-3/n-6 ratio, and in the 22:6 n-3 content in ethanolamine glycerophospholipids and in phosphatidylserine. In contrast, prenatal ethanol consumption significantly increased brain cholesterol mass 1.4-fold and the phospholipid to cholesterol ratio was significantly increased 1.3-fold. These results indicate that brain cholesterol mass was significantly increased in adult rats exposed prenatally to ethanol, but changes in phospholipid mass and phospholipid fatty acid composition were extremely limited. Importantly, suppression of post-natal ethanol consumption was not sufficient to reverse the large increase in cholesterol observed in the adult rats. PMID:23996454

  6. Brain-size evolution and sociality in Carnivora

    PubMed Central

    Finarelli, John A.; Flynn, John J.

    2009-01-01

    Increased encephalization, or larger brain volume relative to body mass, is a repeated theme in vertebrate evolution. Here we present an extensive sampling of relative brain sizes in fossil and extant taxa in the mammalian order Carnivora (cats, dogs, bears, weasels, and their relatives). By using Akaike Information Criterion model selection and endocranial volume and body mass data for 289 species (including 125 fossil taxa), we document clade-specific evolutionary transformations in encephalization allometries. These evolutionary transformations include multiple independent encephalization increases and decreases in addition to a remarkably static basal Carnivora allometry that characterizes much of the suborder Feliformia and some taxa in the suborder Caniformia across much of their evolutionary history, emphasizing that complex processes shaped the modern distribution of encephalization across Carnivora. This analysis also permits critical evaluation of the social brain hypothesis (SBH), which predicts a close association between sociality and increased encephalization. Previous analyses based on living species alone appeared to support the SBH with respect to Carnivora, but those results are entirely dependent on data from modern Canidae (dogs). Incorporation of fossil data further reveals that no association exists between sociality and encephalization across Carnivora and that support for sociality as a causal agent of encephalization increase disappears for this clade. PMID:19474299

  7. Isolation and culture of neurospheres from the adult newt brain.

    PubMed

    Hameed, Liyakath Ali Shahul; Simon, András

    2015-01-01

    Neural stem cells (NSCs) give rise to neurons in the adult brain and are possible targets in regenerative therapies. In vitro cultures of NSCs as neurospheres have been established from cells isolated from diverse species. Newts are exceptional regenerators among vertebrates. These animals are able to efficiently replace neurons following ablation of those by activation and subsequent differentiation of NSCs. Here we describe the method for isolating and culturing of NSCs from the newt brain both during self-renewing and differentiating conditions. Newt NSC culture provides a useful tool for functional studies of NSC fate with the potential of resulting in novel regenerative strategies.

  8. Clinical review: Brain-body temperature differences in adults with severe traumatic brain injury.

    PubMed

    Childs, Charmaine; Lunn, Kueh Wern

    2013-04-22

    Surrogate or 'proxy' measures of brain temperature are used in the routine management of patients with brain damage. The prevailing view is that the brain is 'hotter' than the body. The polarity and magnitude of temperature differences between brain and body, however, remains unclear after severe traumatic brain injury (TBI). The focus of this systematic review is on the adult patient admitted to intensive/neurocritical care with a diagnosis of severe TBI (Glasgow Coma Scale score of less than 8). The review considered studies that measured brain temperature and core body temperature. Articles published in English from the years 1980 to 2012 were searched in databases, CINAHL, PubMed, Scopus, Web of Science, Science Direct, Ovid SP, Mednar and ProQuest Dissertations & Theses Database. For the review, publications of randomised controlled trials, non-randomised controlled trials, before and after studies, cohort studies, case-control studies and descriptive studies were considered for inclusion. Of 2,391 records identified via the search strategies, 37 were retrieved for detailed examination (including two via hand searching). Fifteen were reviewed and assessed for methodological quality. Eleven studies were included in the systematic review providing 15 brain-core body temperature comparisons. The direction of mean brain-body temperature differences was positive (brain higher than body temperature) and negative (brain lower than body temperature). Hypothermia is associated with large brain-body temperature differences. Brain temperature cannot be predicted reliably from core body temperature. Concurrent monitoring of brain and body temperature is recommended in patients where risk of temperature-related neuronal damage is a cause for clinical concern and when deliberate induction of below-normal body temperature is instituted.

  9. Comprehensive cellular‐resolution atlas of the adult human brain

    PubMed Central

    Royall, Joshua J.; Sunkin, Susan M.; Ng, Lydia; Facer, Benjamin A.C.; Lesnar, Phil; Guillozet‐Bongaarts, Angie; McMurray, Bergen; Szafer, Aaron; Dolbeare, Tim A.; Stevens, Allison; Tirrell, Lee; Benner, Thomas; Caldejon, Shiella; Dalley, Rachel A.; Dee, Nick; Lau, Christopher; Nyhus, Julie; Reding, Melissa; Riley, Zackery L.; Sandman, David; Shen, Elaine; van der Kouwe, Andre; Varjabedian, Ani; Write, Michelle; Zollei, Lilla; Dang, Chinh; Knowles, James A.; Koch, Christof; Phillips, John W.; Sestan, Nenad; Wohnoutka, Paul; Zielke, H. Ronald; Hohmann, John G.; Jones, Allan R.; Bernard, Amy; Hawrylycz, Michael J.; Hof, Patrick R.; Fischl, Bruce

    2016-01-01

    ABSTRACT Detailed anatomical understanding of the human brain is essential for unraveling its functional architecture, yet current reference atlases have major limitations such as lack of whole‐brain coverage, relatively low image resolution, and sparse structural annotation. We present the first digital human brain atlas to incorporate neuroimaging, high‐resolution histology, and chemoarchitecture across a complete adult female brain, consisting of magnetic resonance imaging (MRI), diffusion‐weighted imaging (DWI), and 1,356 large‐format cellular resolution (1 µm/pixel) Nissl and immunohistochemistry anatomical plates. The atlas is comprehensively annotated for 862 structures, including 117 white matter tracts and several novel cyto‐ and chemoarchitecturally defined structures, and these annotations were transferred onto the matching MRI dataset. Neocortical delineations were done for sulci, gyri, and modified Brodmann areas to link macroscopic anatomical and microscopic cytoarchitectural parcellations. Correlated neuroimaging and histological structural delineation allowed fine feature identification in MRI data and subsequent structural identification in MRI data from other brains. This interactive online digital atlas is integrated with existing Allen Institute for Brain Science gene expression atlases and is publicly accessible as a resource for the neuroscience community. J. Comp. Neurol. 524:3127–3481, 2016. © 2016 The Authors The Journal of Comparative Neurology Published by Wiley Periodicals, Inc. PMID:27418273

  10. Comprehensive cellular-resolution atlas of the adult human brain.

    PubMed

    Ding, Song-Lin; Royall, Joshua J; Sunkin, Susan M; Ng, Lydia; Facer, Benjamin A C; Lesnar, Phil; Guillozet-Bongaarts, Angie; McMurray, Bergen; Szafer, Aaron; Dolbeare, Tim A; Stevens, Allison; Tirrell, Lee; Benner, Thomas; Caldejon, Shiella; Dalley, Rachel A; Dee, Nick; Lau, Christopher; Nyhus, Julie; Reding, Melissa; Riley, Zackery L; Sandman, David; Shen, Elaine; van der Kouwe, Andre; Varjabedian, Ani; Write, Michelle; Zollei, Lilla; Dang, Chinh; Knowles, James A; Koch, Christof; Phillips, John W; Sestan, Nenad; Wohnoutka, Paul; Zielke, H Ronald; Hohmann, John G; Jones, Allan R; Bernard, Amy; Hawrylycz, Michael J; Hof, Patrick R; Fischl, Bruce; Lein, Ed S

    2016-11-01

    Detailed anatomical understanding of the human brain is essential for unraveling its functional architecture, yet current reference atlases have major limitations such as lack of whole-brain coverage, relatively low image resolution, and sparse structural annotation. We present the first digital human brain atlas to incorporate neuroimaging, high-resolution histology, and chemoarchitecture across a complete adult female brain, consisting of magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI), and 1,356 large-format cellular resolution (1 µm/pixel) Nissl and immunohistochemistry anatomical plates. The atlas is comprehensively annotated for 862 structures, including 117 white matter tracts and several novel cyto- and chemoarchitecturally defined structures, and these annotations were transferred onto the matching MRI dataset. Neocortical delineations were done for sulci, gyri, and modified Brodmann areas to link macroscopic anatomical and microscopic cytoarchitectural parcellations. Correlated neuroimaging and histological structural delineation allowed fine feature identification in MRI data and subsequent structural identification in MRI data from other brains. This interactive online digital atlas is integrated with existing Allen Institute for Brain Science gene expression atlases and is publicly accessible as a resource for the neuroscience community. J. Comp. Neurol. 524:3127-3481, 2016. © 2016 The Authors The Journal of Comparative Neurology Published by Wiley Periodicals, Inc. PMID:27418273

  11. Comprehensive cellular-resolution atlas of the adult human brain.

    PubMed

    Ding, Song-Lin; Royall, Joshua J; Sunkin, Susan M; Ng, Lydia; Facer, Benjamin A C; Lesnar, Phil; Guillozet-Bongaarts, Angie; McMurray, Bergen; Szafer, Aaron; Dolbeare, Tim A; Stevens, Allison; Tirrell, Lee; Benner, Thomas; Caldejon, Shiella; Dalley, Rachel A; Dee, Nick; Lau, Christopher; Nyhus, Julie; Reding, Melissa; Riley, Zackery L; Sandman, David; Shen, Elaine; van der Kouwe, Andre; Varjabedian, Ani; Write, Michelle; Zollei, Lilla; Dang, Chinh; Knowles, James A; Koch, Christof; Phillips, John W; Sestan, Nenad; Wohnoutka, Paul; Zielke, H Ronald; Hohmann, John G; Jones, Allan R; Bernard, Amy; Hawrylycz, Michael J; Hof, Patrick R; Fischl, Bruce; Lein, Ed S

    2016-11-01

    Detailed anatomical understanding of the human brain is essential for unraveling its functional architecture, yet current reference atlases have major limitations such as lack of whole-brain coverage, relatively low image resolution, and sparse structural annotation. We present the first digital human brain atlas to incorporate neuroimaging, high-resolution histology, and chemoarchitecture across a complete adult female brain, consisting of magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI), and 1,356 large-format cellular resolution (1 µm/pixel) Nissl and immunohistochemistry anatomical plates. The atlas is comprehensively annotated for 862 structures, including 117 white matter tracts and several novel cyto- and chemoarchitecturally defined structures, and these annotations were transferred onto the matching MRI dataset. Neocortical delineations were done for sulci, gyri, and modified Brodmann areas to link macroscopic anatomical and microscopic cytoarchitectural parcellations. Correlated neuroimaging and histological structural delineation allowed fine feature identification in MRI data and subsequent structural identification in MRI data from other brains. This interactive online digital atlas is integrated with existing Allen Institute for Brain Science gene expression atlases and is publicly accessible as a resource for the neuroscience community. J. Comp. Neurol. 524:3127-3481, 2016. © 2016 The Authors The Journal of Comparative Neurology Published by Wiley Periodicals, Inc.

  12. When larger brains do not have more neurons: increased numbers of cells are compensated by decreased average cell size across mouse individuals

    PubMed Central

    Herculano-Houzel, Suzana; Messeder, Débora J.; Fonseca-Azevedo, Karina; Pantoja, Nilma A.

    2015-01-01

    There is a strong trend toward increased brain size in mammalian evolution, with larger brains composed of more and larger neurons than smaller brains across species within each mammalian order. Does the evolution of increased numbers of brain neurons, and thus larger brain size, occur simply through the selection of individuals with more and larger neurons, and thus larger brains, within a population? That is, do individuals with larger brains also have more, and larger, neurons than individuals with smaller brains, such that allometric relationships across species are simply an extension of intraspecific scaling? Here we show that this is not the case across adult male mice of a similar age. Rather, increased numbers of neurons across individuals are accompanied by increased numbers of other cells and smaller average cell size of both types, in a trade-off that explains how increased brain mass does not necessarily ensue. Fundamental regulatory mechanisms thus must exist that tie numbers of neurons to numbers of other cells and to average cell size within individual brains. Finally, our results indicate that changes in brain size in evolution are not an extension of individual variation in numbers of neurons, but rather occur through step changes that must simultaneously increase numbers of neurons and cause cell size to increase, rather than decrease. PMID:26082686

  13. Ketone-body utilization by homogenates of adult rat brain

    SciTech Connect

    Lopes-Cardozo, M.; Klein, W.

    1982-06-01

    The regulation of ketone-body metabolism and the quantitative importance of ketone bodies as lipid precursors in adult rat brain has been studied in vitro. Utilization of ketone bodies and of pyruvate by homogenates of adult rat brain was measured and the distribution of /sup 14/C from (3-/sup 14/C)ketone bodies among the metabolic products was analysed. The rate of ketone-body utilization was maximal in the presence of added Krebs-cycle intermediates and uncouplers of oxidative phosphorylation. The consumption of acetoacetate was faster than that of D-3-hydroxybutyrate, whereas, pyruvate produced twice as much acetyl-CoA as acetoacetate under optimal conditions. Millimolar concentrations of ATP in the presence of uncoupler lowered the consumption of ketone bodies but not of pyruvate. Indirect evidence is presented suggesting that ATP interferes specifically with the mitochondrial uptake of ketone bodies. Interconversion of ketone bodies and the accumulation of acid-soluble intermediates (mainly citrate and glutamate) accounted for the major part of ketone-body utilization, whereas only a small part was oxidized to CO/sub 2/. Ketone bodies were not incorporated into lipids or protein. We conclude that adult rat-brain homogenates use ketone bodies exclusively for oxidative purposes.

  14. Localization and regulation of PML bodies in the adult mouse brain.

    PubMed

    Hall, Małgorzata H; Magalska, Adriana; Malinowska, Monika; Ruszczycki, Błażej; Czaban, Iwona; Patel, Satyam; Ambrożek-Latecka, Magdalena; Zołocińska, Ewa; Broszkiewicz, Hanna; Parobczak, Kamil; Nair, Rajeevkumar R; Rylski, Marcin; Pawlak, Robert; Bramham, Clive R; Wilczyński, Grzegorz M

    2016-06-01

    PML is a tumor suppressor protein involved in the pathogenesis of promyelocytic leukemia. In non-neuronal cells, PML is a principal component of characteristic nuclear bodies. In the brain, PML has been implicated in the control of embryonic neurogenesis, and in certain physiological and pathological phenomena in the adult brain. Yet, the cellular and subcellular localization of the PML protein in the brain, including its presence in the nuclear bodies, has not been investigated comprehensively. Because the formation of PML bodies appears to be a key aspect in the function of the PML protein, we investigated the presence of these structures and their anatomical distribution, throughout the adult mouse brain. We found that PML is broadly expressed across the gray matter, with the highest levels in the cerebral and cerebellar cortices. In the cerebral cortex PML is present exclusively in neurons, in which it forms well-defined nuclear inclusions containing SUMO-1, SUMO 2/3, but not Daxx. At the ultrastructural level, the appearance of neuronal PML bodies differs from the classic one, i.e., the solitary structure with more or less distinctive capsule. Rather, neuronal PML bodies have the form of small PML protein aggregates located in the close vicinity of chromatin threads. The number, size, and signal intensity of neuronal PML bodies are dynamically influenced by immobilization stress and seizures. Our study indicates that PML bodies are broadly involved in activity-dependent nuclear phenomena in adult neurons.

  15. Evolution of brain size in the Palaeognath lineage, with an emphasis on new zealand ratites.

    PubMed

    Corfield, Jeremy R; Wild, J Martin; Hauber, Mark E; Parsons, Stuart; Kubke, M Fabiana

    2008-01-01

    Brain size in vertebrates varies principally with body size. Although many studies have examined the variation of brain size in birds, there is little information on Palaeognaths, which include the ratite lineage of kiwi, emu, ostrich and extinct moa, as well as the tinamous. Therefore, we set out to determine to what extent the evolution of brain size in Palaeognaths parallels that of other birds, i.e., Neognaths, by analyzing the variation in the relative sizes of the brain and cerebral hemispheres of several species of ratites and tinamous. Our results indicate that the Palaeognaths possess relatively smaller brains and cerebral hemispheres than the Neognaths, with the exception of the kiwi radiation (Apteryx spp.). The external morphology and relatively large size of the brain of Apteryx, as well as the relatively large size of its telencephalon, contrast with other Palaeognaths, including two species of historically sympatric moa, suggesting that unique selective pressures towards increasing brain size accompanied the evolution of kiwi. Indeed, the size of the cerebral hemispheres with respect to total brain size of kiwi is rivaled only by a handful of parrots and songbirds, despite a lack of evidence of any advanced behavioral/cognitive abilities such as those reported for parrots and crows. In addition, the enlargement in brain and telencephalon size of the kiwi occurs despite the fact that this is a precocial bird. These findings form an exception to, and hence challenge, the current rules that govern changes in relative brain size in birds.

  16. Brain network activity in monolingual and bilingual older adults.

    PubMed

    Grady, Cheryl L; Luk, Gigi; Craik, Fergus I M; Bialystok, Ellen

    2015-01-01

    Bilingual older adults typically have better performance on tasks of executive control (EC) than do their monolingual peers, but differences in brain activity due to language experience are not well understood. Based on studies showing a relation between the dynamic range of brain network activity and performance on EC tasks, we hypothesized that life-long bilingual older adults would show increased functional connectivity relative to monolinguals in networks related to EC. We assessed intrinsic functional connectivity and modulation of activity in task vs. fixation periods in two brain networks that are active when EC is engaged, the frontoparietal control network (FPC) and the salience network (SLN). We also examined the default mode network (DMN), which influences behavior through reduced activity during tasks. We found stronger intrinsic functional connectivity in the FPC and DMN in bilinguals than in monolinguals. Although there were no group differences in the modulation of activity across tasks and fixation, bilinguals showed stronger correlations than monolinguals between intrinsic connectivity in the FPC and task-related increases of activity in prefrontal and parietal regions. This bilingual difference in network connectivity suggests that language experience begun in childhood and continued throughout adulthood influences brain networks in ways that may provide benefits in later life.

  17. Brain network activity in monolingual and bilingual older adults.

    PubMed

    Grady, Cheryl L; Luk, Gigi; Craik, Fergus I M; Bialystok, Ellen

    2015-01-01

    Bilingual older adults typically have better performance on tasks of executive control (EC) than do their monolingual peers, but differences in brain activity due to language experience are not well understood. Based on studies showing a relation between the dynamic range of brain network activity and performance on EC tasks, we hypothesized that life-long bilingual older adults would show increased functional connectivity relative to monolinguals in networks related to EC. We assessed intrinsic functional connectivity and modulation of activity in task vs. fixation periods in two brain networks that are active when EC is engaged, the frontoparietal control network (FPC) and the salience network (SLN). We also examined the default mode network (DMN), which influences behavior through reduced activity during tasks. We found stronger intrinsic functional connectivity in the FPC and DMN in bilinguals than in monolinguals. Although there were no group differences in the modulation of activity across tasks and fixation, bilinguals showed stronger correlations than monolinguals between intrinsic connectivity in the FPC and task-related increases of activity in prefrontal and parietal regions. This bilingual difference in network connectivity suggests that language experience begun in childhood and continued throughout adulthood influences brain networks in ways that may provide benefits in later life. PMID:25445783

  18. Brain Network Activity in Monolingual and Bilingual Older Adults

    PubMed Central

    Grady, Cheryl L.; Luk, Gigi; Craik, Fergus I.M.; Bialystok, Ellen

    2016-01-01

    Bilingual older adults typically have better performance on tasks of executive control (EC) than do their monolingual peers, but differences in brain activity due to language experience are not well understood. Based on studies showing a relation between the dynamic range of brain network activity and performance on EC tasks, we hypothesized that life-long bilingual older adults would show increased functional connectivity relative to monolinguals in networks related to EC. We assessed intrinsic functional connectivity and modulation of activity in task vs. fixation periods in two brain networks that are active when EC is engaged, the frontoparietal control network (FPC) and the salience network (SLN). We also examined the default mode network (DMN), which influences behavior through reduced activity during tasks. We found stronger intrinsic functional connectivity in the FPC and DMN in bilinguals than in monolinguals. Although there were no group differences in the modulation of activity across tasks and fixation, bilinguals showed stronger correlations than monolinguals between intrinsic connectivity in the FPC and task-related increases of activity in prefrontal and parietal regions. This bilingual difference in network connectivity suggests that language experience begun in childhood and continued throughout adulthood influences brain networks in ways that may provide benefits in later life. PMID:25445783

  19. Landmark-based morphometrics of the normal adult brain using MRI.

    PubMed

    Free, S L; O'Higgins, P; Maudgil, D D; Dryden, I L; Lemieux, L; Fish, D R; Shorvon, S D

    2001-05-01

    We describe the application of statistical shape analysis to homologous landmarks on the cortical surface of the adult human brain. Statistical shape analysis has a sound theoretical basis. Landmarks are identified on the surface of a 3-D reconstruction of the segmented cortical surface from magnetic resonance image (MRI) data. Using publicly available software (morphologika) the location and size dependence of the landmarks are removed and the differences in landmark distribution across subjects are analysed using principal component analysis. These differences, representing shape differences between subjects, can be visually assessed using wireframe models and transformation grids. The MRI data of 58 adult brains (27 female and 15 left handed) were examined. Shape differences in the whole brain are described which concern the relative orientation of frontal lobe sulci. Analysis of all 116 hemispheres revealed a statistically significant difference (P < 0.001) between left and right hemispheres. This finding was significant for right- but not left-handed subjects alone. No other significant age, gender, handedness, or brain-size correlations with shape differences were found.

  20. Litter Size Predicts Adult Stereotypic Behavior in Female Laboratory Mice

    PubMed Central

    Bechard, Allison; Nicholson, Anthony; Mason, Georgia

    2012-01-01

    Stereotypic behaviors are repetitive invariant behaviors that are common in many captive species and potentially indicate compromised welfare and suitability as research subjects. Adult laboratory mice commonly perform stereotypic bar-gnawing, route-tracing, and back-flipping, although great individual variation in frequency occurs. Early life factors (for example, level of maternal care received) have lasting effects on CNS functioning and abilities to cope with stress and therefore may also affect stereotypic behavior in offspring. Access to maternal resources and care are influenced by the number of pups in a litter; therefore, we examined both litter size and its potential correlate, weight at weaning, as early environmental predictors of adult stereotypic behavior in laboratory mice. Further, we assessed the effects on offspring stereotypic behavior of delaying the separation of mother and pups (weaning) beyond the standard 21 d of age. Analyzing stereotypic behavior in 3 different mouse colonies composed of 2 inbred strains (C57BL/6N and C57BL/6J) and an outbred stock (CD1[ICR]) revealed significant positive correlation between litter size and stereotypic behavior in female, but not male, mice. Weight and age at weaning did not significantly affect levels of stereotypy in either sex. Litter size therefore may be a useful indicator of individual predisposition to stereotypic behavior in female laboratory mice. PMID:23043805

  1. Normative data for subcortical regional volumes over the lifetime of the adult human brain.

    PubMed

    Potvin, Olivier; Mouiha, Abderazzak; Dieumegarde, Louis; Duchesne, Simon

    2016-08-15

    Normative data for volumetric estimates of brain structures are necessary to adequately assess brain volume alterations in individuals with suspected neurological or psychiatric conditions. Although many studies have described age and sex effects in healthy individuals for brain morphometry assessed via magnetic resonance imaging, proper normative values allowing to quantify potential brain abnormalities are needed. We developed norms for volumetric estimates of subcortical brain regions based on cross-sectional magnetic resonance scans from 2790 healthy individuals aged 18 to 94years using 23 samples provided by 21 independent research groups. The segmentation was conducted using FreeSurfer, a widely used and freely available automated segmentation software. Models predicting subcortical regional volumes of each hemisphere were produced including age, sex, estimated total intracranial volume (eTIV), scanner manufacturer, magnetic field strength, and interactions as predictors. The mean explained variance by the models was 48%. For most regions, age, sex and eTIV predicted most of the explained variance while manufacturer, magnetic field strength and interactions predicted a limited amount. Estimates of the expected volumes of an individual based on its characteristics and the scanner characteristics can be obtained using derived formulas. For a new individual, significance test for volume abnormality, effect size and estimated percentage of the normative population with a smaller volume can be obtained. Normative values were validated in independent samples of healthy adults and in adults with Alzheimer's disease and schizophrenia. PMID:27165761

  2. An anatomic gene expression atlas of the adult mouse brain.

    PubMed

    Ng, Lydia; Bernard, Amy; Lau, Chris; Overly, Caroline C; Dong, Hong-Wei; Kuan, Chihchau; Pathak, Sayan; Sunkin, Susan M; Dang, Chinh; Bohland, Jason W; Bokil, Hemant; Mitra, Partha P; Puelles, Luis; Hohmann, John; Anderson, David J; Lein, Ed S; Jones, Allan R; Hawrylycz, Michael

    2009-03-01

    Studying gene expression provides a powerful means of understanding structure-function relationships in the nervous system. The availability of genome-scale in situ hybridization datasets enables new possibilities for understanding brain organization based on gene expression patterns. The Anatomic Gene Expression Atlas (AGEA) is a new relational atlas revealing the genetic architecture of the adult C57Bl/6J mouse brain based on spatial correlations across expression data for thousands of genes in the Allen Brain Atlas (ABA). The AGEA includes three discovery tools for examining neuroanatomical relationships and boundaries: (1) three-dimensional expression-based correlation maps, (2) a hierarchical transcriptome-based parcellation of the brain and (3) a facility to retrieve from the ABA specific genes showing enriched expression in local correlated domains. The utility of this atlas is illustrated by analysis of genetic organization in the thalamus, striatum and cerebral cortex. The AGEA is a publicly accessible online computational tool integrated with the ABA (http://mouse.brain-map.org/agea). PMID:19219037

  3. Evolution of ASPM is associated with both increases and decreases in brain size in primates.

    PubMed

    Montgomery, Stephen H; Mundy, Nicholas I

    2012-03-01

    A fundamental trend during primate evolution has been the expansion of brain size. However, this trend was reversed in the Callitrichidae (marmosets and tamarins), which have secondarily evolved smaller brains associated with a reduction in body size. The recent pursuit of the genetic basis of brain size evolution has largely focused on episodes of brain expansion, but new insights may be gained by investigating episodes of brain size reduction. Previous results suggest two genes (ASPM and CDK5RAP2) associated with microcephaly, a human neurodevelopmental disorder, may have an evolutionary function in primate brain expansion. Here we use new sequences encoding key functional domains from 12 species of callitrichids to show that positive selection has acted on ASPM across callitrichid evolution and the rate of ASPM evolution is significantly negatively correlated with callitrichid brain size, whereas the evolution of CDK5RAP2 shows no correlation with brain size. Our findings strongly suggest that ASPM has a previously unsuspected role in the evolution of small brains in primates. ASPM is therefore intimately linked to both evolutionary increases and decreases in brain size in anthropoids and is a key target for natural selection acting on brain size. PMID:22380452

  4. Acute moderate exercise enhances compensatory brain activation in older adults.

    PubMed

    Hyodo, Kazuki; Dan, Ippeita; Suwabe, Kazuya; Kyutoku, Yasushi; Yamada, Yuhki; Akahori, Mitsuya; Byun, Kyeongho; Kato, Morimasa; Soya, Hideaki

    2012-11-01

    A growing number of reports state that regular exercise enhances brain function in older adults. Recently a functional near-infrared spectroscopy (fNIRS) study revealed that an acute bout of moderate exercise enhanced activation of the left dorsolateral prefrontal cortex (L-DLPFC) associated with Stroop interference in young adults. Whether this acute effect is also applicable to older adults was examined. Sixteen older adults performed a color-word matching Stroop task before and after 10 minutes of exercise on a cycle ergometer at a moderate intensity. Cortical hemodynamics of the prefrontal area was monitored with a fNIRS during the Stroop task. We analyzed Stroop interference (incongruent-neutral) as Stroop performance. Though activation for Stroop interference was found in the bilateral prefrontal area before the acute bout of exercise, activation of the right frontopolar area (R-FPA) was enhanced after exercise. In the majority of participants, this coincided with improved performance reflected in Stroop interference results. Thus, an acute bout of moderate exercise improved Stroop performance in older adults, and this was associated with contralateral compensatory activation. PMID:22300952

  5. Acute moderate exercise enhances compensatory brain activation in older adults.

    PubMed

    Hyodo, Kazuki; Dan, Ippeita; Suwabe, Kazuya; Kyutoku, Yasushi; Yamada, Yuhki; Akahori, Mitsuya; Byun, Kyeongho; Kato, Morimasa; Soya, Hideaki

    2012-11-01

    A growing number of reports state that regular exercise enhances brain function in older adults. Recently a functional near-infrared spectroscopy (fNIRS) study revealed that an acute bout of moderate exercise enhanced activation of the left dorsolateral prefrontal cortex (L-DLPFC) associated with Stroop interference in young adults. Whether this acute effect is also applicable to older adults was examined. Sixteen older adults performed a color-word matching Stroop task before and after 10 minutes of exercise on a cycle ergometer at a moderate intensity. Cortical hemodynamics of the prefrontal area was monitored with a fNIRS during the Stroop task. We analyzed Stroop interference (incongruent-neutral) as Stroop performance. Though activation for Stroop interference was found in the bilateral prefrontal area before the acute bout of exercise, activation of the right frontopolar area (R-FPA) was enhanced after exercise. In the majority of participants, this coincided with improved performance reflected in Stroop interference results. Thus, an acute bout of moderate exercise improved Stroop performance in older adults, and this was associated with contralateral compensatory activation.

  6. Insular dwarfism in hippos and a model for brain size reduction in Homo floresiensis.

    PubMed

    Weston, Eleanor M; Lister, Adrian M

    2009-05-01

    Body size reduction in mammals is usually associated with only moderate brain size reduction, because the brain and sensory organs complete their growth before the rest of the body during ontogeny. On this basis, 'phyletic dwarfs' are predicted to have a greater relative brain size than 'phyletic giants'. However, this trend has been questioned in the special case of dwarfism of mammals on islands. Here we show that the endocranial capacities of extinct dwarf species of hippopotamus from Madagascar are up to 30% smaller than those of a mainland African ancestor scaled to equivalent body mass. These results show that brain size reduction is much greater than predicted from an intraspecific 'late ontogenetic' model of dwarfism in which brain size scales to body size with an exponent of 0.35. The nature of the proportional change or grade shift observed here indicates that selective pressures on brain size are potentially independent of those on body size. This study demonstrates empirically that it is mechanistically possible for dwarf mammals on islands to evolve significantly smaller brains than would be predicted from a model of dwarfing based on the intraspecific scaling of the mainland ancestor. Our findings challenge current understanding of brain-body allometric relationships in mammals and suggest that the process of dwarfism could in principle explain small brain size, a factor relevant to the interpretation of the small-brained hominin found on the Island of Flores, Indonesia. PMID:19424156

  7. Neuroimaging in adult penetrating brain injury: a guide for radiographers

    PubMed Central

    Temple, Nikki; Donald, Cortny; Skora, Amanda; Reed, Warren

    2015-01-01

    Penetrating brain injuries (PBI) are a medical emergency, often resulting in complex damage and high mortality rates. Neuroimaging is essential to evaluate the location and extent of injuries, and to manage them accordingly. Currently, a myriad of imaging modalities are included in the diagnostic workup for adult PBI, including skull radiography, computed tomography (CT), magnetic resonance imaging (MRI) and angiography, with each modality providing their own particular benefits. This literature review explores the current modalities available for investigating PBI and aims to assist in decision making for the appropriate use of diagnostic imaging when presented with an adult PBI. Based on the current literature, the authors have developed an imaging pathway for adult penetrating brain injury that functions as both a learning tool and reference guide for radiographers and other health professionals. Currently, CT is recommended as the imaging modality of choice for the initial assessment of PBI patients, while MRI is important in the sub-acute setting where it aids prognosis prediction and rehabilitation planning, Additional follow-up imaging, such as angiography, should be dependent upon clinical findings. PMID:26229677

  8. Neuroimaging in adult penetrating brain injury: a guide for radiographers

    SciTech Connect

    Temple, Nikki; Donald, Cortny; Skora, Amanda; Reed, Warren

    2015-06-15

    Penetrating brain injuries (PBI) are a medical emergency, often resulting in complex damage and high mortality rates. Neuroimaging is essential to evaluate the location and extent of injuries, and to manage them accordingly. Currently, a myriad of imaging modalities are included in the diagnostic workup for adult PBI, including skull radiography, computed tomography (CT), magnetic resonance imaging (MRI) and angiography, with each modality providing their own particular benefits. This literature review explores the current modalities available for investigating PBI and aims to assist in decision making for the appropriate use of diagnostic imaging when presented with an adult PBI. Based on the current literature, the authors have developed an imaging pathway for adult penetrating brain injury that functions as both a learning tool and reference guide for radiographers and other health professionals. Currently, CT is recommended as the imaging modality of choice for the initial assessment of PBI patients, while MRI is important in the sub-acute setting where it aids prognosis prediction and rehabilitation planning, Additional follow-up imaging, such as angiography, should be dependent upon clinical findings.

  9. Is the social brain theory applicable to human individual differences? Relationship between sociability personality dimension and brain size.

    PubMed

    Horváth, Klára; Martos, János; Mihalik, Béla; Bódizs, Róbert

    2011-06-17

    Our study intends to examine whether the social brain theory is applicable to human individual differences. According to the social brain theory primates have larger brains as it could be expected from their body sizes due to the adaptation to a more complex social life. Regarding humans there were few studies about the relationship between theory of mind and frontal and temporal brain lobes. We hypothesized that these brain lobes, as well as the whole cerebrum and neocortex are in connection with the Sociability personality dimension that is associated with individuals' social lives. Our findings support this hypothesis as Sociability correlated positively with the examined brain structures if we control the effects of body size differences and age. These results suggest that the social brain theory can be extended to human interindividual differences and they have some implications to personality psychology too.

  10. Brain size affects female but not male survival under predation threat

    PubMed Central

    Kotrschal, Alexander; Buechel, Séverine D; Zala, Sarah M; Corral-Lopez, Alberto; Penn, Dustin J; Kolm, Niclas; Sorci, Gabriele

    2015-01-01

    There is remarkable diversity in brain size among vertebrates, but surprisingly little is known about how ecological species interactions impact the evolution of brain size. Using guppies, artificially selected for large and small brains, we determined how brain size affects survival under predation threat in a naturalistic environment. We cohoused mixed groups of small- and large-brained individuals in six semi-natural streams with their natural predator, the pike cichlid, and monitored survival in weekly censuses over 5 months. We found that large-brained females had 13.5% higher survival compared to small-brained females, whereas the brain size had no discernible effect on male survival. We suggest that large-brained females have a cognitive advantage that allows them to better evade predation, whereas large-brained males are more colourful, which may counteract any potential benefits of brain size. Our study provides the first experimental evidence that trophic interactions can affect the evolution of brain size. PMID:25960088

  11. Brain size affects female but not male survival under predation threat.

    PubMed

    Kotrschal, Alexander; Buechel, Séverine D; Zala, Sarah M; Corral-Lopez, Alberto; Penn, Dustin J; Kolm, Niclas

    2015-07-01

    There is remarkable diversity in brain size among vertebrates, but surprisingly little is known about how ecological species interactions impact the evolution of brain size. Using guppies, artificially selected for large and small brains, we determined how brain size affects survival under predation threat in a naturalistic environment. We cohoused mixed groups of small- and large-brained individuals in six semi-natural streams with their natural predator, the pike cichlid, and monitored survival in weekly censuses over 5 months. We found that large-brained females had 13.5% higher survival compared to small-brained females, whereas the brain size had no discernible effect on male survival. We suggest that large-brained females have a cognitive advantage that allows them to better evade predation, whereas large-brained males are more colourful, which may counteract any potential benefits of brain size. Our study provides the first experimental evidence that trophic interactions can affect the evolution of brain size. PMID:25960088

  12. Quantitative genetic analysis of brain size variation in sticklebacks: support for the mosaic model of brain evolution

    PubMed Central

    Noreikiene, Kristina; Herczeg, Gábor; Gonda, Abigél; Balázs, Gergely; Husby, Arild; Merilä, Juha

    2015-01-01

    The mosaic model of brain evolution postulates that different brain regions are relatively free to evolve independently from each other. Such independent evolution is possible only if genetic correlations among the different brain regions are less than unity. We estimated heritabilities, evolvabilities and genetic correlations of relative size of the brain, and its different regions in the three-spined stickleback (Gasterosteus aculeatus). We found that heritabilities were low (average h2 = 0.24), suggesting a large plastic component to brain architecture. However, evolvabilities of different brain parts were moderate, suggesting the presence of additive genetic variance to sustain a response to selection in the long term. Genetic correlations among different brain regions were low (average rG = 0.40) and significantly less than unity. These results, along with those from analyses of phenotypic and genetic integration, indicate a high degree of independence between different brain regions, suggesting that responses to selection are unlikely to be severely constrained by genetic and phenotypic correlations. Hence, the results give strong support for the mosaic model of brain evolution. However, the genetic correlation between brain and body size was high (rG = 0.89), suggesting a constraint for independent evolution of brain and body size in sticklebacks. PMID:26108633

  13. Astaxanthin reduces ischemic brain injury in adult rats.

    PubMed

    Shen, Hui; Kuo, Chi-Chung; Chou, Jenny; Delvolve, Alice; Jackson, Shelley N; Post, Jeremy; Woods, Amina S; Hoffer, Barry J; Wang, Yun; Harvey, Brandon K

    2009-06-01

    Astaxanthin (ATX) is a dietary carotenoid of crustaceans and fish that contributes to their coloration. Dietary ATX is important for development and survival of salmonids and crustaceans and has been shown to reduce cardiac ischemic injury in rodents. The purpose of this study was to examine whether ATX can protect against ischemic injury in the mammalian brain. Adult rats were injected intracerebroventricularly with ATX or vehicle prior to a 60-min middle cerebral artery occlusion (MCAo). ATX was present in the infarction area at 70-75 min after onset of MCAo. Treatment with ATX, compared to vehicle, increased locomotor activity in stroke rats and reduced cerebral infarction at 2 d after MCAo. To evaluate the protective mechanisms of ATX against stroke, brain tissues were assayed for free radical damage, apoptosis, and excitoxicity. ATX antagonized ischemia-mediated loss of aconitase activity and reduced glutamate release, lipid peroxidation, translocation of cytochrome c, and TUNEL labeling in the ischemic cortex. ATX did not alter physiological parameters, such as body temperature, brain temperature, cerebral blood flow, blood gases, blood pressure, and pH. Collectively, our data suggest that ATX can reduce ischemia-related injury in brain tissue through the inhibition of oxidative stress, reduction of glutamate release, and antiapoptosis. ATX may be clinically useful for patients vulnerable or prone to ischemic events. PMID:19218497

  14. Testosterone affects language areas of the adult human brain

    PubMed Central

    Hahn, Andreas; Kranz, Georg S.; Sladky, Ronald; Kaufmann, Ulrike; Ganger, Sebastian; Hummer, Allan; Seiger, Rene; Spies, Marie; Vanicek, Thomas; Winkler, Dietmar; Kasper, Siegfried; Windischberger, Christian; Swaab, Dick F.

    2016-01-01

    Abstract Although the sex steroid hormone testosterone is integrally involved in the development of language processing, ethical considerations mostly limit investigations to single hormone administrations. To circumvent this issue we assessed the influence of continuous high‐dose hormone application in adult female‐to‐male transsexuals. Subjects underwent magnetic resonance imaging before and after 4 weeks of testosterone treatment, with each scan including structural, diffusion weighted and functional imaging. Voxel‐based morphometry analysis showed decreased gray matter volume with increasing levels of bioavailable testosterone exclusively in Broca's and Wernicke's areas. Particularly, this may link known sex differences in language performance to the influence of testosterone on relevant brain regions. Using probabilistic tractography, we further observed that longitudinal changes in testosterone negatively predicted changes in mean diffusivity of the corresponding structural connection passing through the extreme capsule. Considering a related increase in myelin staining in rodents, this potentially reflects a strengthening of the fiber tract particularly involved in language comprehension. Finally, functional images at resting‐state were evaluated, showing increased functional connectivity between the two brain regions with increasing testosterone levels. These findings suggest testosterone‐dependent neuroplastic adaptations in adulthood within language‐specific brain regions and connections. Importantly, deteriorations in gray matter volume seem to be compensated by enhancement of corresponding structural and functional connectivity. Hum Brain Mapp 37:1738–1748, 2016. © 2016 Wiley Periodicals, Inc. PMID:26876303

  15. Astaxanthin reduces ischemic brain injury in adult rats.

    PubMed

    Shen, Hui; Kuo, Chi-Chung; Chou, Jenny; Delvolve, Alice; Jackson, Shelley N; Post, Jeremy; Woods, Amina S; Hoffer, Barry J; Wang, Yun; Harvey, Brandon K

    2009-06-01

    Astaxanthin (ATX) is a dietary carotenoid of crustaceans and fish that contributes to their coloration. Dietary ATX is important for development and survival of salmonids and crustaceans and has been shown to reduce cardiac ischemic injury in rodents. The purpose of this study was to examine whether ATX can protect against ischemic injury in the mammalian brain. Adult rats were injected intracerebroventricularly with ATX or vehicle prior to a 60-min middle cerebral artery occlusion (MCAo). ATX was present in the infarction area at 70-75 min after onset of MCAo. Treatment with ATX, compared to vehicle, increased locomotor activity in stroke rats and reduced cerebral infarction at 2 d after MCAo. To evaluate the protective mechanisms of ATX against stroke, brain tissues were assayed for free radical damage, apoptosis, and excitoxicity. ATX antagonized ischemia-mediated loss of aconitase activity and reduced glutamate release, lipid peroxidation, translocation of cytochrome c, and TUNEL labeling in the ischemic cortex. ATX did not alter physiological parameters, such as body temperature, brain temperature, cerebral blood flow, blood gases, blood pressure, and pH. Collectively, our data suggest that ATX can reduce ischemia-related injury in brain tissue through the inhibition of oxidative stress, reduction of glutamate release, and antiapoptosis. ATX may be clinically useful for patients vulnerable or prone to ischemic events.

  16. Midsagittal brain variation and MRI shape analysis of the precuneus in adult individuals.

    PubMed

    Bruner, Emiliano; Rangel de Lázaro, Gizéh; de la Cuétara, José Manuel; Martín-Loeches, Manuel; Colom, Roberto; Jacobs, Heidi I L

    2014-04-01

    Recent analyses indicate that the precuneus is one of the main centres of integration in terms of functional and structural processes within the human brain. This neuroanatomical element is formed by different subregions, involved in visuo-spatial integration, memory and self-awareness. We analysed the midsagittal brain shape in a sample of adult humans (n = 90) to evidence the patterns of variability and geometrical organization of this area. Interestingly, the major brain covariance pattern within adult humans is strictly associated with the relative proportions of the precuneus. Its morphology displays a marked individual variation, both in terms of geometry (mostly in its longitudinal dimensions) and anatomy (patterns of convolution). No patent differences are evident between males and females, and the allometric effect of size is minimal. However, in terms of morphology, the precuneus does not represent an individual module, being influenced by different neighbouring structures. Taking into consideration the apparent involvement of the precuneus in higher-order human brain functions and evolution, its wide variation further stresses the important role of these deep parietal areas in modern neuroanatomical organization.

  17. Brain changes in older adults at very low risk for Alzheimer's disease.

    PubMed

    Fjell, Anders M; McEvoy, Linda; Holland, Dominic; Dale, Anders M; Walhovd, Kristine B

    2013-05-01

    Alzheimer's disease (AD) has a slow onset, so it is challenging to distinguish brain changes in healthy elderly persons from incipient AD. One-year brain changes with a distinct frontotemporal pattern have been shown in older adults. However, it is not clear to what extent these changes may have been affected by undetected, early AD. To address this, we estimated 1-year atrophy by magnetic resonance imaging (MRI) in 132 healthy elderly persons who had remained free of diagnosed mild cognitive impairment or AD for at least 3 years. We found significant volumetric reductions throughout the brain. The sample was further divided into low-risk groups based on clinical, biomarker, genetic, or cognitive criteria. Although sample sizes varied, significant reductions were observed in all groups, with rates and topographical distribution of atrophy comparable to that of the full sample. Volume reductions were especially pronounced in the default mode network, closely matching the previously described frontotemporal pattern of changes in healthy aging. Atrophy in the hippocampus predicted change in memory, with no additional default mode network contributions. In conclusion, reductions in regional brain volumes can be detected over the course of 1 year even in older adults who are unlikely to be in a presymptomatic stage of AD.

  18. Midsagittal brain variation and MRI shape analysis of the precuneus in adult individuals

    PubMed Central

    Bruner, Emiliano; Rangel de Lázaro, Gizéh; de la Cuétara, José Manuel; Martín-Loeches, Manuel; Colom, Roberto; Jacobs, Heidi I L

    2014-01-01

    Recent analyses indicate that the precuneus is one of the main centres of integration in terms of functional and structural processes within the human brain. This neuroanatomical element is formed by different subregions, involved in visuo-spatial integration, memory and self-awareness. We analysed the midsagittal brain shape in a sample of adult humans (n = 90) to evidence the patterns of variability and geometrical organization of this area. Interestingly, the major brain covariance pattern within adult humans is strictly associated with the relative proportions of the precuneus. Its morphology displays a marked individual variation, both in terms of geometry (mostly in its longitudinal dimensions) and anatomy (patterns of convolution). No patent differences are evident between males and females, and the allometric effect of size is minimal. However, in terms of morphology, the precuneus does not represent an individual module, being influenced by different neighbouring structures. Taking into consideration the apparent involvement of the precuneus in higher-order human brain functions and evolution, its wide variation further stresses the important role of these deep parietal areas in modern neuroanatomical organization. PMID:24397462

  19. Doublecortin expression levels in adult brain reflect neurogenesis.

    PubMed

    Couillard-Despres, Sebastien; Winner, Beate; Schaubeck, Susanne; Aigner, Robert; Vroemen, Maurice; Weidner, Norbert; Bogdahn, Ulrich; Winkler, Jürgen; Kuhn, Hans-Georg; Aigner, Ludwig

    2005-01-01

    Progress in the field of neurogenesis is currently limited by the lack of tools enabling fast and quantitative analysis of neurogenesis in the adult brain. Doublecortin (DCX) has recently been used as a marker for neurogenesis. However, it was not clear whether DCX could be used to assess modulations occurring in the rate of neurogenesis in the adult mammalian central nervous system following lesioning or stimulatory factors. Using two paradigms increasing neurogenesis levels (physical activity and epileptic seizures), we demonstrate that quantification of DCX-expressing cells allows for an accurate measurement of modulations in the rate of adult neurogenesis. Importantly, we excluded induction of DCX expression during physiological or reactive gliogenesis and excluded also DCX re-expression during regenerative axonal growth. Our data validate DCX as a reliable and specific marker that reflects levels of adult neurogenesis and its modulation. We demonstrate that DCX is a valuable alternative to techniques currently used to measure the levels of neurogenesis. Importantly, in contrast to conventional techniques, analysis of neurogenesis through the detection of DCX does not require in vivo labelling of proliferating cells, thereby opening new avenues for the study of human neurogenesis under normal and pathological conditions. PMID:15654838

  20. Relative Brain and Brain Part Sizes Provide Only Limited Evidence that Machiavellian Behaviour in Cleaner Wrasse Is Cognitively Demanding.

    PubMed

    Chojnacka, Dominika; Isler, Karin; Barski, Jaroslaw Jerzy; Bshary, Redouan

    2015-01-01

    It is currently widely accepted that the complexity of a species' social life is a major determinant of its brain complexity, as predicted by the social brain hypothesis. However, it remains a challenge to explain what social complexity exactly is and what the best corresponding measures of brain anatomy are. Absolute and relative size of the brain and of the neocortex have often been used as a proxy to predict cognitive performance. Here, we apply the logic of the social brain hypothesis to marine cleaning mutualism involving the genus Labroides. These wrasses remove ectoparasites from 'client' reef fish. Conflict occurs as wrasse prefer client mucus over ectoparasites, where mucus feeding constitutes cheating. As a result of this conflict, cleaner wrasse show remarkable Machiavellian-like behaviour. Using own data as well as available data from the literature, we investigated whether the general brain anatomy of Labroides provides any indication that their Machiavellian behaviour is associated with a more complex brain. Neither data set provided evidence for an increased encephalisation index compared to other wrasse species. Published data on relative sizes of brain parts in 25 species of the order Perciformes suggests that only the diencephalon is relatively enlarged in Labroides dimidiatus. This part contains various nuclei of the social decision making network. In conclusion, gross brain anatomy yields little evidence for the hypothesis that strategic behaviour in cleaning selects for larger brains, while future research should focus on more detailed aspects like the sizes of specific nuclei as well as their cryoarchitectonic structure and connectivity.

  1. Predator-driven brain size evolution in natural populations of Trinidadian killifish (Rivulus hartii).

    PubMed

    Walsh, Matthew R; Broyles, Whitnee; Beston, Shannon M; Munch, Stephan B

    2016-07-13

    Vertebrates exhibit extensive variation in relative brain size. It has long been assumed that this variation is the product of ecologically driven natural selection. Yet, despite more than 100 years of research, the ecological conditions that select for changes in brain size are unclear. Recent laboratory selection experiments showed that selection for larger brains is associated with increased survival in risky environments. Such results lead to the prediction that increased predation should favour increased brain size. Work on natural populations, however, foreshadows the opposite trajectory of evolution; increased predation favours increased boldness, slower learning, and may thereby select for a smaller brain. We tested the influence of predator-induced mortality on brain size evolution by quantifying brain size variation in a Trinidadian killifish, Rivulus hartii, from communities that differ in predation intensity. We observed strong genetic differences in male (but not female) brain size between fish communities; second generation laboratory-reared males from sites with predators exhibited smaller brains than Rivulus from sites in which they are the only fish present. Such trends oppose the results of recent laboratory selection experiments and are not explained by trade-offs with other components of fitness. Our results suggest that increased male brain size is favoured in less risky environments because of the fitness benefits associated with faster rates of learning and problem-solving behaviour. PMID:27412278

  2. Evaluation of an automatic brain segmentation method developed for neonates on adult MR brain images

    NASA Astrophysics Data System (ADS)

    Moeskops, Pim; Viergever, Max A.; Benders, Manon J. N. L.; Išgum, Ivana

    2015-03-01

    Automatic brain tissue segmentation is of clinical relevance in images acquired at all ages. The literature presents a clear distinction between methods developed for MR images of infants, and methods developed for images of adults. The aim of this work is to evaluate a method developed for neonatal images in the segmentation of adult images. The evaluated method employs supervised voxel classification in subsequent stages, exploiting spatial and intensity information. Evaluation was performed using images available within the MRBrainS13 challenge. The obtained average Dice coefficients were 85.77% for grey matter, 88.66% for white matter, 81.08% for cerebrospinal fluid, 95.65% for cerebrum, and 96.92% for intracranial cavity, currently resulting in the best overall ranking. The possibility of applying the same method to neonatal as well as adult images can be of great value in cross-sectional studies that include a wide age range.

  3. Head circumference and brain size in autism spectrum disorder: A systematic review and meta-analysis.

    PubMed

    Sacco, Roberto; Gabriele, Stefano; Persico, Antonio M

    2015-11-30

    Macrocephaly and brain overgrowth have been associated with autism spectrum disorder. We performed a systematic review and meta-analysis to provide an overall estimate of effect size and statistical significance for both head circumference and total brain volume in autism. Our literature search strategy identified 261 and 391 records, respectively; 27 studies defining percentages of macrocephalic patients and 44 structural brain imaging studies providing total brain volumes for patients and controls were included in our meta-analyses. Head circumference was significantly larger in autistic compared to control individuals, with 822/5225 (15.7%) autistic individuals displaying macrocephaly. Structural brain imaging studies measuring brain volume estimated effect size. The effect size is higher in low functioning autistics compared to high functioning and ASD individuals. Brain overgrowth was recorded in 142/1558 (9.1%) autistic patients. Finally, we found a significant interaction between age and total brain volume, resulting in larger head circumference and brain size during early childhood. Our results provide conclusive effect sizes and prevalence rates for macrocephaly and brain overgrowth in autism, confirm the variation of abnormal brain growth with age, and support the inclusion of this endophenotype in multi-biomarker diagnostic panels for clinical use. PMID:26456415

  4. An empirical EEG analysis in brain death diagnosis for adults.

    PubMed

    Chen, Zhe; Cao, Jianting; Cao, Yang; Zhang, Yue; Gu, Fanji; Zhu, Guoxian; Hong, Zhen; Wang, Bin; Cichocki, Andrzej

    2008-09-01

    Electroencephalogram (EEG) is often used in the confirmatory test for brain death diagnosis in clinical practice. Because EEG recording and monitoring is relatively safe for the patients in deep coma, it is believed to be valuable for either reducing the risk of brain death diagnosis (while comparing other tests such as the apnea) or preventing mistaken diagnosis. The objective of this paper is to study several statistical methods for quantitative EEG analysis in order to help bedside or ambulatory monitoring or diagnosis. We apply signal processing and quantitative statistical analysis for the EEG recordings of 32 adult patients. For EEG signal processing, independent component analysis (ICA) was applied to separate the independent source components, followed by Fourier and time-frequency analysis. For quantitative EEG analysis, we apply several statistical complexity measures to the EEG signals and evaluate the differences between two groups of patients: the subjects in deep coma, and the subjects who were categorized as brain death. We report statistically significant differences of quantitative statistics with real-life EEG recordings in such a clinical study, and we also present interpretation and discussions on the preliminary experimental results.

  5. Comments on "Brain Size and Cerebral Glucose Metabolic Rate in Nonspecific Mental Retardation and Down Syndrome."

    ERIC Educational Resources Information Center

    Willerman, Lee; Schultz, Robert T.

    1995-01-01

    The relationship between mental retardation and brain size is discussed. Research suggests that a common path for many otherwise idiopathic mild retardation cases (genetic or environmental) could be small brain size, indicating reduced information processing capacity. Suggestions are made for further research on neuron number. (SLD)

  6. Investment in higher order central processing regions is not constrained by brain size in social insects

    PubMed Central

    Muscedere, Mario L.; Gronenberg, Wulfila; Moreau, Corrie S.; Traniello, James F. A.

    2014-01-01

    The extent to which size constrains the evolution of brain organization and the genesis of complex behaviour is a central, unanswered question in evolutionary neuroscience. Advanced cognition has long been linked to the expansion of specific brain compartments, such as the neocortex in vertebrates and the mushroom bodies in insects. Scaling constraints that limit the size of these brain regions in small animals may therefore be particularly significant to behavioural evolution. Recent findings from studies of paper wasps suggest miniaturization constrains the size of central sensory processing brain centres (mushroom body calyces) in favour of peripheral, sensory input centres (antennal and optic lobes). We tested the generality of this hypothesis in diverse eusocial hymenopteran species (ants, bees and wasps) exhibiting striking variation in body size and thus brain size. Combining multiple neuroanatomical datasets from these three taxa, we found no universal size constraint on brain organization within or among species. In fact, small-bodied ants with miniscule brains had mushroom body calyces proportionally as large as or larger than those of wasps and bees with brains orders of magnitude larger. Our comparative analyses suggest that brain organization in ants is shaped more by natural selection imposed by visual demands than intrinsic design limitations. PMID:24741016

  7. Microfiberoptic fluorescence photobleaching reveals size-dependent macromolecule diffusion in extracellular space deep in brain.

    PubMed

    Zador, Zsolt; Magzoub, Mazin; Jin, Songwan; Manley, Geoffrey T; Papadopoulos, Marios C; Verkman, A S

    2008-03-01

    Diffusion in brain extracellular space (ECS) is important for nonsynaptic intercellular communication, extracellular ionic buffering, and delivery of drugs and metabolites. We measured macromolecular diffusion in normally light-inaccessible regions of mouse brain by microfiberoptic epifluorescence photobleaching, in which a fiberoptic with a micron-size tip is introduced deep in brain tissue. In brain cortex, the diffusion of a noninteracting molecule [fluorescein isothiocyanate (FITC)-dextran, 70 kDa] was slowed 4.5 +/- 0.5-fold compared with its diffusion in water (D(o)/D), and was depth-independent down to 800 microm from the brain surface. Diffusion was significantly accelerated (D(o)/D of 2.9+/-0.3) in mice lacking the glial water channel aquaporin-4. FITC-dextran diffusion varied greatly in different regions of brain, with D(o)/D of 3.5 +/- 0.3 in hippocampus and 7.4 +/- 0.3 in thalamus. Remarkably, D(o)/D in deep brain was strongly dependent on solute size, whereas diffusion in cortex changed little with solute size. Mathematical modeling of ECS diffusion required nonuniform ECS dimensions in deep brain, which we call "heterometricity," to account for the size-dependent diffusion. Our results provide the first data on molecular diffusion in ECS deep in brain in vivo and demonstrate previously unrecognized hindrance and heterometricity for diffusion of large macromolecules in deep brain.

  8. The effect of brain size evolution on feeding propensity, digestive efficiency, and juvenile growth.

    PubMed

    Kotrschal, Alexander; Corral-Lopez, Alberto; Szidat, Sönke; Kolm, Niclas

    2015-11-01

    One key hypothesis in the study of brain size evolution is the expensive tissue hypothesis; the idea that increased investment into the brain should be compensated by decreased investment into other costly organs, for instance the gut. Although the hypothesis is supported by both comparative and experimental evidence, little is known about the potential changes in energetic requirements or digestive traits following such evolutionary shifts in brain and gut size. Organisms may meet the greater metabolic requirements of larger brains despite smaller guts via increased food intake or better digestion. But increased investment in the brain may also hamper somatic growth. To test these hypotheses we here used guppy (Poecilia reticulata) brain size selection lines with a pronounced negative association between brain and gut size and investigated feeding propensity, digestive efficiency (DE), and juvenile growth rate. We did not find any difference in feeding propensity or DE between large- and small-brained individuals. Instead, we found that large-brained females had slower growth during the first 10 weeks after birth. Our study provides experimental support that investment into larger brains at the expense of gut tissue carries costs that are not necessarily compensated by a more efficient digestive system.

  9. The effect of brain size evolution on feeding propensity, digestive efficiency, and juvenile growth

    PubMed Central

    Kotrschal, Alexander; Corral‐Lopez, Alberto; Szidat, Sönke; Kolm, Niclas

    2015-01-01

    One key hypothesis in the study of brain size evolution is the expensive tissue hypothesis; the idea that increased investment into the brain should be compensated by decreased investment into other costly organs, for instance the gut. Although the hypothesis is supported by both comparative and experimental evidence, little is known about the potential changes in energetic requirements or digestive traits following such evolutionary shifts in brain and gut size. Organisms may meet the greater metabolic requirements of larger brains despite smaller guts via increased food intake or better digestion. But increased investment in the brain may also hamper somatic growth. To test these hypotheses we here used guppy (Poecilia reticulata) brain size selection lines with a pronounced negative association between brain and gut size and investigated feeding propensity, digestive efficiency (DE), and juvenile growth rate. We did not find any difference in feeding propensity or DE between large‐ and small‐brained individuals. Instead, we found that large‐brained females had slower growth during the first 10 weeks after birth. Our study provides experimental support that investment into larger brains at the expense of gut tissue carries costs that are not necessarily compensated by a more efficient digestive system. PMID:26420573

  10. The effect of brain size evolution on feeding propensity, digestive efficiency, and juvenile growth.

    PubMed

    Kotrschal, Alexander; Corral-Lopez, Alberto; Szidat, Sönke; Kolm, Niclas

    2015-11-01

    One key hypothesis in the study of brain size evolution is the expensive tissue hypothesis; the idea that increased investment into the brain should be compensated by decreased investment into other costly organs, for instance the gut. Although the hypothesis is supported by both comparative and experimental evidence, little is known about the potential changes in energetic requirements or digestive traits following such evolutionary shifts in brain and gut size. Organisms may meet the greater metabolic requirements of larger brains despite smaller guts via increased food intake or better digestion. But increased investment in the brain may also hamper somatic growth. To test these hypotheses we here used guppy (Poecilia reticulata) brain size selection lines with a pronounced negative association between brain and gut size and investigated feeding propensity, digestive efficiency (DE), and juvenile growth rate. We did not find any difference in feeding propensity or DE between large- and small-brained individuals. Instead, we found that large-brained females had slower growth during the first 10 weeks after birth. Our study provides experimental support that investment into larger brains at the expense of gut tissue carries costs that are not necessarily compensated by a more efficient digestive system. PMID:26420573

  11. Expression change in Angiopoietin-1 underlies change in relative brain size in fish

    PubMed Central

    Chen, Yu-Chia; Harrison, Peter W.; Kotrschal, Alexander; Kolm, Niclas; Mank, Judith E.; Panula, Pertti

    2015-01-01

    Brain size varies substantially across the animal kingdom and is often associated with cognitive ability; however, the genetic architecture underpinning natural variation in these key traits is virtually unknown. In order to identify the genetic architecture and loci underlying variation in brain size, we analysed both coding sequence and expression for all the loci expressed in the telencephalon in replicate populations of guppies (Poecilia reticulata) artificially selected for large and small relative brain size. A single gene, Angiopoietin-1 (Ang-1), a regulator of angiogenesis and suspected driver of neural development, was differentially expressed between large- and small-brain populations. Zebra fish (Danio rerio) morphants showed that mild knock down of Ang-1 produces a small-brained phenotype that could be rescued with Ang-1 mRNA. Translation inhibition of Ang-1 resulted in smaller brains in larvae and increased expression of Notch-1, which regulates differentiation of neural stem cells. In situ analysis of newborn large- and small-brained guppies revealed matching expression patterns of Ang-1 and Notch-1 to those observed in zebrafish larvae. Taken together, our results suggest that the genetic architecture affecting brain size in our population may be surprisingly simple, and Ang-1 may be a potentially important locus in the evolution of vertebrate brain size and cognitive ability. PMID:26108626

  12. Reversed brain size sexual dimorphism accompanies loss of parental care in white sticklebacks

    PubMed Central

    Samuk, Kieran; Iritani, Davis; Schluter, Dolph

    2014-01-01

    Uncovering factors that shape variation in brain morphology remains a major challenge in evolutionary biology. Recently, it has been shown that brain size is positively associated with level of parental care behavior in various taxa. One explanation for this pattern is that the cognitive demands of performing complex parental care may require increased brain size. This idea is known as the parental brain hypothesis (PBH). We set out to test the predictions of this hypothesis in wild populations of threespine stickleback (Gasterosteus aculeatus). These fish are commonly known to exhibit (1) uniparental male care and (2) sexual dimorphism in brain size (males>females). To test the PBH, we took advantage of the existence of closely related populations of stickleback that display variation in parental care behavior: common marine threespine sticklebacks (uniparental male care) and white threespine sticklebacks (no care). To begin, we quantified genetic differentiation among two common populations and three white populations from Nova Scotia. We found overall low differentiation among populations, although FST was increased in between-type comparisons. We then measured the brain weights of males and females from all five populations along with two additional common populations from British Columbia. We found that sexual dimorphism in brain size is reversed in white stickleback populations: males have smaller brains than females. Thus, while several alternatives need to be ruled out, the PBH appears to be a reasonable explanation for sexual dimorphism in brain size in threespine sticklebacks. PMID:25473476

  13. Expression change in Angiopoietin-1 underlies change in relative brain size in fish.

    PubMed

    Chen, Yu-Chia; Harrison, Peter W; Kotrschal, Alexander; Kolm, Niclas; Mank, Judith E; Panula, Pertti

    2015-07-01

    Brain size varies substantially across the animal kingdom and is often associated with cognitive ability; however, the genetic architecture underpinning natural variation in these key traits is virtually unknown. In order to identify the genetic architecture and loci underlying variation in brain size, we analysed both coding sequence and expression for all the loci expressed in the telencephalon in replicate populations of guppies (Poecilia reticulata) artificially selected for large and small relative brain size. A single gene, Angiopoietin-1 (Ang-1), a regulator of angiogenesis and suspected driver of neural development, was differentially expressed between large- and small-brain populations. Zebra fish (Danio rerio) morphants showed that mild knock down of Ang-1 produces a small-brained phenotype that could be rescued with Ang-1 mRNA. Translation inhibition of Ang-1 resulted in smaller brains in larvae and increased expression of Notch-1, which regulates differentiation of neural stem cells. In situ analysis of newborn large- and small-brained guppies revealed matching expression patterns of Ang-1 and Notch-1 to those observed in zebrafish larvae. Taken together, our results suggest that the genetic architecture affecting brain size in our population may be surprisingly simple, and Ang-1 may be a potentially important locus in the evolution of vertebrate brain size and cognitive ability.

  14. Wnts in adult brain: from synaptic plasticity to cognitive deficiencies

    PubMed Central

    Oliva, Carolina A.; Vargas, Jessica Y.; Inestrosa, Nibaldo C.

    2013-01-01

    During development of the central nervous system the Wnt signaling pathway has been implicated in a wide spectrum of physiological processes, including neuronal connectivity and synapse formation. Wnt proteins and components of the Wnt pathway are expressed in the brain since early development to the adult life, however, little is known about its role in mature synapses. Here, we review evidences indicating that Wnt proteins participate in the remodeling of pre- and post-synaptic regions, thus modulating synaptic function. We include the most recent data in the literature showing that Wnts are constantly released in the brain to maintain the basal neural activity. Also, we review the evidences that involve components of the Wnt pathway in the development of neurological and mental disorders, including a special emphasis on in vivo studies that relate behavioral abnormalities to deficiencies in Wnt signaling. Finally, we include the evidences that support a neuroprotective role of Wnt proteins in Alzheimer’s disease. We postulate that deregulation in Wnt signaling might have a fundamental role in the origin of neurological diseases, by altering the synaptic function at stages where the phenotype is not yet established but when the cognitive decline starts. PMID:24348327

  15. Exploratory case-control study of brain tumors in adults

    SciTech Connect

    Burch, J.D.; Craib, K.J.; Choi, B.C.; Miller, A.B.; Risch, H.A.; Howe, G.R.

    1987-04-01

    An exploratory study of brain tumors in adults was carried out using 215 cases diagnosed in Southern Ontario between 1979 and 1982, with an individually matched, hospital control series. Significantly elevated risks were observed for reported use of spring water, drinking of wine, and consumption of pickled fish, together with a significant protective effect for the regular consumption of any of several types of fruit. While these factors are consistent with a role for N-nitroso compounds in the etiology of these tumors, for several other factors related to this hypothesis, no association was observed. Occupation in the rubber industry was associated with a significant relative risk of 9.0, though no other occupational associations were seen. Two previously unreported associations were with smoking nonfilter cigarettes with a significant trend and with the use of hair dyes or sprays. The data do not support an association between physical head trauma requiring medical attention and risk of brain tumors and indicate that exposure to ionizing radiation and vinyl chloride monomer does not contribute any appreciable fraction of attributable risk in the population studied. The findings warrant further detailed investigation in future epidemiologic studies.

  16. Traumatic brain injury: endocrine consequences in children and adults.

    PubMed

    Richmond, Erick; Rogol, Alan D

    2014-02-01

    Traumatic brain injury (TBI) is a common cause of death and disability in young adults with consequences ranging from physical disabilities to long-term cognitive, behavioral, psychological and social defects. Recent data suggest that pituitary hormone deficiency is not infrequent among TBI survivors; the prevalence of reported hypopituitarism following TBI varies widely among published studies. The most common cause of TBI is motor vehicle accidents, including pedestrian-car and bicycle car encounters, falls, child abuse, violence and sports injuries. Prevalence of hypopituitarism, from total to isolated pituitary deficiency, ranges from 5 to 90 %. The time interval between TBI and pituitary function evaluation is one of the major factors responsible for variations in the prevalence of hypopituitarism reported. Endocrine dysfunction after TBI in children and adolescents is common. Adolescence is a time of growth, freedom and adjustment, consequently TBI is also common in this group. Sports-related TBI is an important public health concern, but many cases are unrecognized and unreported. Sports that are associated with an increased risk of TBI include those involving contact and/or collisions such as boxing, football, soccer, ice hockey, rugby, and the martial arts, as well as high velocity sports such as cycling, motor racing, equestrian sports, skiing and roller skating. The aim of this paper is to summarize the best evidence of TBI as a cause of pituitary deficiency in children and adults. PMID:24030696

  17. Narrative skills following traumatic brain injury in children and adults.

    PubMed

    Biddle, K R; McCabe, A; Bliss, L S

    1996-01-01

    Personal narratives serve an important function in virtually all societies (Peterson & McCabe, 1991). Through narratives individuals make sense of their experiences and represent themselves to others (Bruner, 1990). The ability to produce narratives has been linked to academic success (Feagans, 1982). Persons who have sustained a traumatic brain injury (TBI) are at risk for impaired narrative ability (Dennis, 1991). However, a paucity of information exists on the discourse abilities of persons with TBI. This is partly due to a lack of reliable tools with which to assess narrative discourse. The present study utilized dependency analysis (Deese, 1984) to document and describe the narrative discourse impairments of children and adults with TBI. Ten children (mean age 12;0) and 10 adults (mean age 35;2) were compared with matched controls. Dependency analysis reliably differentiated the discourse of the individuals with TBI from their controls. Individuals with TBI were significantly more dysfluent than their matched controls. Furthermore, their performance on the narrative task revealed a striking listener burden.

  18. Relative Brain and Brain Part Sizes Provide Only Limited Evidence that Machiavellian Behaviour in Cleaner Wrasse Is Cognitively Demanding

    PubMed Central

    Chojnacka, Dominika; Isler, Karin; Barski, Jaroslaw Jerzy; Bshary, Redouan

    2015-01-01

    It is currently widely accepted that the complexity of a species’ social life is a major determinant of its brain complexity, as predicted by the social brain hypothesis. However, it remains a challenge to explain what social complexity exactly is and what the best corresponding measures of brain anatomy are. Absolute and relative size of the brain and of the neocortex have often been used as a proxy to predict cognitive performance. Here, we apply the logic of the social brain hypothesis to marine cleaning mutualism involving the genus Labroides. These wrasses remove ectoparasites from ‘client’ reef fish. Conflict occurs as wrasse prefer client mucus over ectoparasites, where mucus feeding constitutes cheating. As a result of this conflict, cleaner wrasse show remarkable Machiavellian-like behaviour. Using own data as well as available data from the literature, we investigated whether the general brain anatomy of Labroides provides any indication that their Machiavellian behaviour is associated with a more complex brain. Neither data set provided evidence for an increased encephalisation index compared to other wrasse species. Published data on relative sizes of brain parts in 25 species of the order Perciformes suggests that only the diencephalon is relatively enlarged in Labroides dimidiatus. This part contains various nuclei of the social decision making network. In conclusion, gross brain anatomy yields little evidence for the hypothesis that strategic behaviour in cleaning selects for larger brains, while future research should focus on more detailed aspects like the sizes of specific nuclei as well as their cryoarchitectonic structure and connectivity. PMID:26263490

  19. Interspecies avian brain chimeras reveal that large brain size differences are influenced by cell-interdependent processes.

    PubMed

    Chen, Chun-Chun; Balaban, Evan; Jarvis, Erich D

    2012-01-01

    Like humans, birds that exhibit vocal learning have relatively delayed telencephalon maturation, resulting in a disproportionately smaller brain prenatally but enlarged telencephalon in adulthood relative to vocal non-learning birds. To determine if this size difference results from evolutionary changes in cell-autonomous or cell-interdependent developmental processes, we transplanted telencephala from zebra finch donors (a vocal-learning species) into Japanese quail hosts (a vocal non-learning species) during the early neural tube stage (day 2 of incubation), and harvested the chimeras at later embryonic stages (between 9-12 days of incubation). The donor and host tissues fused well with each other, with known major fiber pathways connecting the zebra finch and quail parts of the brain. However, the overall sizes of chimeric finch telencephala were larger than non-transplanted finch telencephala at the same developmental stages, even though the proportional sizes of telencephalic subregions and fiber tracts were similar to normal finches. There were no significant changes in the size of chimeric quail host midbrains, even though they were innervated by the physically smaller zebra finch brain, including the smaller retinae of the finch eyes. Chimeric zebra finch telencephala had a decreased cell density relative to normal finches. However, cell nucleus size differences between each species were maintained as in normal birds. These results suggest that telencephalic size development is partially cell-interdependent, and that the mechanisms controlling the size of different brain regions may be functionally independent. PMID:22860132

  20. Interspecies Avian Brain Chimeras Reveal That Large Brain Size Differences Are Influenced by Cell–Interdependent Processes

    PubMed Central

    Chen, Chun-Chun; Balaban, Evan; Jarvis, Erich D.

    2012-01-01

    Like humans, birds that exhibit vocal learning have relatively delayed telencephalon maturation, resulting in a disproportionately smaller brain prenatally but enlarged telencephalon in adulthood relative to vocal non-learning birds. To determine if this size difference results from evolutionary changes in cell-autonomous or cell-interdependent developmental processes, we transplanted telencephala from zebra finch donors (a vocal-learning species) into Japanese quail hosts (a vocal non-learning species) during the early neural tube stage (day 2 of incubation), and harvested the chimeras at later embryonic stages (between 9–12 days of incubation). The donor and host tissues fused well with each other, with known major fiber pathways connecting the zebra finch and quail parts of the brain. However, the overall sizes of chimeric finch telencephala were larger than non-transplanted finch telencephala at the same developmental stages, even though the proportional sizes of telencephalic subregions and fiber tracts were similar to normal finches. There were no significant changes in the size of chimeric quail host midbrains, even though they were innervated by the physically smaller zebra finch brain, including the smaller retinae of the finch eyes. Chimeric zebra finch telencephala had a decreased cell density relative to normal finches. However, cell nucleus size differences between each species were maintained as in normal birds. These results suggest that telencephalic size development is partially cell-interdependent, and that the mechanisms controlling the size of different brain regions may be functionally independent. PMID:22860132

  1. The relationship between social network body size and the body size norms of Black and Hispanic adults

    PubMed Central

    Winston, Ginger; Phillips, Erica; Wethington, Elaine; Wells, Martin; Devine, Carol M.; Peterson, Janey; Wansink, Brian; Ramos, Rosio; Charlson, Mary

    2015-01-01

    Objective To examine the relationship between the body size norms of Black and Hispanic adults and the body sizes of their social network members. Methods Egocentric network data were examined for 245 adults recruited from 2012–2013 in New York City. A multivariable regression model was used to examine the relationship between participants' perception of normal body size and the body sizes of their network members adjusted for participant age, education, race/ethnicity and network size. Participants' body size norms were also examined stratified by the following characteristics of obese network members: frequency of contact, living proximity, relationship, and importance of relationship. Results Index participants were 89% female with mean body mass index 33.5 kg/m2. There were 2571 network members identified (31% overweight, 10% obese). In the fully adjusted multivariable model, perception of normal body size increased as the number of network members with obesity increased (p < 0.01). Larger body size norms were associated with increased frequency of contact with obese network members (p = 0.04), and obese members living in the home (p = 0.049). Conclusions These findings support a relationship between the body size norms of Black and Hispanic adults and their social network body size. PMID:26705513

  2. Aggressive behavior, brain size and domestication in clonal rainbow trout lines.

    PubMed

    Campbell, Janet M; Carter, Patrick A; Wheeler, Paul A; Thorgaard, Gary H

    2015-03-01

    Domestication causes behavior and brain size changes in many species. We addressed three questions using clonal rainbow trout lines: What are the mirror-elicited aggressive tendencies in lines with varying degrees of domestication? How does brain size relate to genotype and domestication level? Finally, is there a relationship between aggressive behavior and brain size? Clonal lines, although sampling a limited subset of the species variation, provide us with a reproducible experimental system with which we can develop hypotheses for further research. We performed principal component analyses on 12 continuous behavior and brain/body size variables and one discrete behavioral variable ("yawn") and detected several aggression syndromes. Two behaviors, "freeze" and "escape", associated with high domestication; "display" and "yawn" behavior associated with wild lines and "swim against the mirror" behavior associated with semi-wild and domestic lines. Two brain size traits, total brain and olfactory volume, were significantly related to domestication level when taking total body size into account, with domesticated lines having larger total brain volume and olfactory regions. The aggression syndromes identified indicate that future QTL mapping studies on domestication-related traits would likely be fruitful.

  3. Using Structural Equation Modeling to Assess Functional Connectivity in the Brain: Power and Sample Size Considerations

    ERIC Educational Resources Information Center

    Sideridis, Georgios; Simos, Panagiotis; Papanicolaou, Andrew; Fletcher, Jack

    2014-01-01

    The present study assessed the impact of sample size on the power and fit of structural equation modeling applied to functional brain connectivity hypotheses. The data consisted of time-constrained minimum norm estimates of regional brain activity during performance of a reading task obtained with magnetoencephalography. Power analysis was first…

  4. Brain size affects the behavioural response to predators in female guppies (Poecilia reticulata)

    PubMed Central

    van der Bijl, Wouter; Thyselius, Malin; Kotrschal, Alexander; Kolm, Niclas

    2015-01-01

    Large brains are thought to result from selection for cognitive benefits, but how enhanced cognition leads to increased fitness remains poorly understood. One explanation is that increased cognitive ability results in improved monitoring and assessment of predator threats. Here, we use male and female guppies (Poecilia reticulata), artificially selected for large and small brain size, to provide an experimental evaluation of this hypothesis. We examined their behavioural response as singletons, pairs or shoals of four towards a model predator. Large-brained females, but not males, spent less time performing predator inspections, an inherently risky behaviour. Video analysis revealed that large-brained females were further away from the model predator when in pairs but that they habituated quickly towards the model when in shoals of four. Males stayed further away from the predator model than females but again we found no brain size effect in males. We conclude that differences in brain size affect the female predator response. Large-brained females might be able to assess risk better or need less sensory information to reach an accurate conclusion. Our results provide experimental support for the general idea that predation pressure is likely to be important for the evolution of brain size in prey species. PMID:26203003

  5. Brain Size and Cerebral Glucose Metabolic Rate in Nonspecific Retardation and Down Syndrome.

    ERIC Educational Resources Information Center

    Haier, Richard J.; And Others

    1995-01-01

    Brain size and cerebral glucose metabolic rate were determined for 10 individuals with mild mental retardation (MR), 7 individuals with Down syndrome (DS), and 10 matched controls. MR and DS groups both had brain volumes of about 80% compared to controls, with variance greatest within the MR group. (SLD)

  6. Brain size affects the behavioural response to predators in female guppies (Poecilia reticulata).

    PubMed

    van der Bijl, Wouter; Thyselius, Malin; Kotrschal, Alexander; Kolm, Niclas

    2015-08-01

    Large brains are thought to result from selection for cognitive benefits, but how enhanced cognition leads to increased fitness remains poorly understood. One explanation is that increased cognitive ability results in improved monitoring and assessment of predator threats. Here, we use male and female guppies (Poecilia reticulata), artificially selected for large and small brain size, to provide an experimental evaluation of this hypothesis. We examined their behavioural response as singletons, pairs or shoals of four towards a model predator. Large-brained females, but not males, spent less time performing predator inspections, an inherently risky behaviour. Video analysis revealed that large-brained females were further away from the model predator when in pairs but that they habituated quickly towards the model when in shoals of four. Males stayed further away from the predator model than females but again we found no brain size effect in males. We conclude that differences in brain size affect the female predator response. Large-brained females might be able to assess risk better or need less sensory information to reach an accurate conclusion. Our results provide experimental support for the general idea that predation pressure is likely to be important for the evolution of brain size in prey species.

  7. Brain size affects the behavioural response to predators in female guppies (Poecilia reticulata).

    PubMed

    van der Bijl, Wouter; Thyselius, Malin; Kotrschal, Alexander; Kolm, Niclas

    2015-08-01

    Large brains are thought to result from selection for cognitive benefits, but how enhanced cognition leads to increased fitness remains poorly understood. One explanation is that increased cognitive ability results in improved monitoring and assessment of predator threats. Here, we use male and female guppies (Poecilia reticulata), artificially selected for large and small brain size, to provide an experimental evaluation of this hypothesis. We examined their behavioural response as singletons, pairs or shoals of four towards a model predator. Large-brained females, but not males, spent less time performing predator inspections, an inherently risky behaviour. Video analysis revealed that large-brained females were further away from the model predator when in pairs but that they habituated quickly towards the model when in shoals of four. Males stayed further away from the predator model than females but again we found no brain size effect in males. We conclude that differences in brain size affect the female predator response. Large-brained females might be able to assess risk better or need less sensory information to reach an accurate conclusion. Our results provide experimental support for the general idea that predation pressure is likely to be important for the evolution of brain size in prey species. PMID:26203003

  8. Magnetic Resonance Imaging Brain Size/IQ Relations in Turkish University Students.

    ERIC Educational Resources Information Center

    Tan, Uner; Tan, Meliha; Polat, Pinar; Ceylan, Yasar; Suma, Selami; Okur, Adnan

    1999-01-01

    Studied the relation of intelligence quotient (IQ) to brain size on 103 right-handed and left-handed male and female college students in Turkey. Measured cerebral areas and found an overall correlation between brain area and IQ. Discusses some sex differences. (SLD)

  9. Prolongation of Relaxation Time in Extraocular Muscles With Brain Derived Neurotrophic Factor in Adult Rabbit

    PubMed Central

    Nelson, Krysta R.; Stevens, Shanlee M.; McLoon, Linda K.

    2016-01-01

    Purpose We tested the hypothesis that short-term treatment with brain derived neurotrophic factor (BDNF) would alter the contractile characteristics of rabbit extraocular muscle (EOM). Methods One week after injections of BDNF in adult rabbit superior rectus muscles, twitch properties were determined in treated and control muscles in vitro. Muscles were also examined for changes in mean cross-sectional areas, neuromuscular junction size, and percent of myofibers expressing specific myosin heavy chain isoforms, and sarcoendoplasmic reticulum calcium ATPases (SERCA) 1 and 2. Results Brain derived neurotrophic factor–treated muscles had prolonged relaxation times compared with control muscles. Time to 50% relaxation, time to 100% relaxation, and maximum rate of relaxation were increased by 24%, 27%, and 25%, respectively. No significant differences were seen in time to peak force, twitch force, or maximum rate of contraction. Brain derived neurotrophic factor treatment significantly increased mean cross-sectional areas of slow twitch and tonic myofibers, with increased areas ranging from 54% to 146%. Brain derived neurotrophic factor also resulted in an increased percentage of slow twitch myofibers in the orbital layers, ranging from 54% to 77%, and slow-tonic myofibers, ranging from 44% to 62%. No significant changes were seen SERCA1 or 2 expression or in neuromuscular junction size. Conclusions Short-term treatment with BDNF significantly prolonged the duration and rate of relaxation time and increased expression of both slow-twitch and slow-tonic myosin-expressing myofibers without changes in neuromuscular junctions or SERCA expression. The changes induced by BDNF treatment might have potential therapeutic value in dampening/reducing uncontrolled eye oscillations in nystagmus. PMID:27802489

  10. Investigation of genes important in neurodevelopment disorders in adult human brain.

    PubMed

    Maussion, Gilles; Diallo, Alpha B; Gigek, Carolina O; Chen, Elizabeth S; Crapper, Liam; Théroux, Jean-Francois; Chen, Gary G; Vasuta, Cristina; Ernst, Carl

    2015-10-01

    Several neurodevelopmental disorders (NDDs) are caused by mutations in genes expressed in fetal brain, but little is known about these same genes in adult human brain. Here, we test the hypothesis that genes associated with NDDs continue to have a role in adult human brain to explore the idea that NDD symptoms may be partially a result of their adult function rather than just their neurodevelopmental function. To demonstrate adult brain function, we performed expression analyses and ChIPseq in human neural stem cell(NSC) lines at different developmental stages and adult human brain, targeting two genes associated with NDDs, SATB2 and EHMT1, and the WNT signaling gene TCF7L2, which has not been associated with NDDs. Analysis of DNA interaction sites in neural stem cells reveals high (40-50 %) overlap between proliferating and differentiating cells for each gene in temporal space. Studies in adult brain demonstrate that consensus sites are similar to NSCs but occur at different genomic locations. We also performed expression analyses using BrainSpan data for NDD-associated genes SATB2, EHMT1, FMR1, MECP2, MBD5, CTNND2, RAI1, CHD8, GRIN2A, GRIN2B, TCF4, SCN2A, and DYRK1A and find high expression of these genes in adult brain, at least comparable to developing human brain, confirming that genes associated with NDDs likely have a role in adult tissue. Adult function of genes associated with NDDs might be important in clinical disease presentation and may be suitable targets for therapeutic intervention. PMID:26194112

  11. Investigation of genes important in neurodevelopment disorders in adult human brain.

    PubMed

    Maussion, Gilles; Diallo, Alpha B; Gigek, Carolina O; Chen, Elizabeth S; Crapper, Liam; Théroux, Jean-Francois; Chen, Gary G; Vasuta, Cristina; Ernst, Carl

    2015-10-01

    Several neurodevelopmental disorders (NDDs) are caused by mutations in genes expressed in fetal brain, but little is known about these same genes in adult human brain. Here, we test the hypothesis that genes associated with NDDs continue to have a role in adult human brain to explore the idea that NDD symptoms may be partially a result of their adult function rather than just their neurodevelopmental function. To demonstrate adult brain function, we performed expression analyses and ChIPseq in human neural stem cell(NSC) lines at different developmental stages and adult human brain, targeting two genes associated with NDDs, SATB2 and EHMT1, and the WNT signaling gene TCF7L2, which has not been associated with NDDs. Analysis of DNA interaction sites in neural stem cells reveals high (40-50 %) overlap between proliferating and differentiating cells for each gene in temporal space. Studies in adult brain demonstrate that consensus sites are similar to NSCs but occur at different genomic locations. We also performed expression analyses using BrainSpan data for NDD-associated genes SATB2, EHMT1, FMR1, MECP2, MBD5, CTNND2, RAI1, CHD8, GRIN2A, GRIN2B, TCF4, SCN2A, and DYRK1A and find high expression of these genes in adult brain, at least comparable to developing human brain, confirming that genes associated with NDDs likely have a role in adult tissue. Adult function of genes associated with NDDs might be important in clinical disease presentation and may be suitable targets for therapeutic intervention.

  12. The impact of brain size on pilot performance varies with aviation training and years of education.

    PubMed

    Adamson, Maheen M; Samarina, Viktoriya; Xiangyan, Xu; Huynh, Virginia; Kennedy, Quinn; Weiner, Michael; Yesavage, Jerome; Taylor, Joy L

    2010-05-01

    Previous studies have consistently reported age-related changes in cognitive abilities and brain structure. Previous studies also suggest compensatory roles for specialized training, skill, and years of education in the age-related decline of cognitive function. The Stanford/VA Aviation Study examines the influence of specialized training and skill level (expertise) on age-related changes in cognition and brain structure. This preliminary report examines the effect of aviation expertise, years of education, age, and brain size on flight simulator performance in pilots aged 45-68 years. Fifty-one pilots were studied with structural magnetic resonance imaging, flight simulator, and processing speed tasks. There were significant main effects of age (p < .01) and expertise (p < .01), but not of whole brain size (p > .1) or education (p > .1), on flight simulator performance. However, even though age and brain size were correlated (r = -0.41), age differences in flight simulator performance were not explained by brain size. Both aviation expertise and education were involved in an interaction with brain size in predicting flight simulator performance (p < .05). These results point to the importance of examining measures of expertise and their interactions to assess age-related cognitive changes.

  13. New aspects in fenestrated capillary and tissue dynamics in the sensory circumventricular organs of adult brains

    PubMed Central

    Miyata, Seiji

    2015-01-01

    The blood–brain barrier (BBB) generally consists of endothelial tight junction barriers that prevent the free entry of blood-derived substances, thereby maintaining the extracellular environment of the brain. However, the circumventricular organs (CVOs), which are located along the midlines of the brain ventricles, lack these endothelial barriers and have fenestrated capillaries; therefore, they have a number of essential functions, including the transduction of information between the blood circulation and brain. Previous studies have demonstrated the extensive contribution of the CVOs to body fluid and thermal homeostasis, energy balance, the chemoreception of blood-derived substances, and neuroinflammation. In this review, recent advances have been discussed in fenestrated capillary characterization and dynamic tissue reconstruction accompanied by angiogenesis and neurogliogenesis in the sensory CVOs of adult brains. The sensory CVOs, including the organum vasculosum of the lamina terminalis (OVLT), subfornical organ (SFO), and area postrema (AP), have size-selective and heterogeneous vascular permeabilities. Astrocyte-/tanycyte-like neural stem cells (NSCs) sense blood- and cerebrospinal fluid-derived information through the transient receptor potential vanilloid 1, a mechanical/osmotic receptor, Toll-like receptor 4, a lipopolysaccharide receptor, and Nax, a Na-sensing Na channel. They also express tight junction proteins and densely and tightly surround mature neurons to protect them from blood-derived neurotoxic substances, indicating that the NSCs of the CVOs perform BBB functions while maintaining the capacity to differentiate into new neurons and glial cells. In addition to neurogliogenesis, the density of fenestrated capillaries is regulated by angiogenesis, which is accompanied by the active proliferation and sprouting of endothelial cells. Vascular endothelial growth factor (VEGF) signaling may be involved in angiogenesis and neurogliogenesis, both

  14. GABA regulates synaptic integration of newly generated neurons in the adult brain

    NASA Astrophysics Data System (ADS)

    Ge, Shaoyu; Goh, Eyleen L. K.; Sailor, Kurt A.; Kitabatake, Yasuji; Ming, Guo-Li; Song, Hongjun

    2006-02-01

    Adult neurogenesis, the birth and integration of new neurons from adult neural stem cells, is a striking form of structural plasticity and highlights the regenerative capacity of the adult mammalian brain. Accumulating evidence suggests that neuronal activity regulates adult neurogenesis and that new neurons contribute to specific brain functions. The mechanism that regulates the integration of newly generated neurons into the pre-existing functional circuitry in the adult brain is unknown. Here we show that newborn granule cells in the dentate gyrus of the adult hippocampus are tonically activated by ambient GABA (γ-aminobutyric acid) before being sequentially innervated by GABA- and glutamate-mediated synaptic inputs. GABA, the major inhibitory neurotransmitter in the adult brain, initially exerts an excitatory action on newborn neurons owing to their high cytoplasmic chloride ion content. Conversion of GABA-induced depolarization (excitation) into hyperpolarization (inhibition) in newborn neurons leads to marked defects in their synapse formation and dendritic development in vivo. Our study identifies an essential role for GABA in the synaptic integration of newly generated neurons in the adult brain, and suggests an unexpected mechanism for activity-dependent regulation of adult neurogenesis, in which newborn neurons may sense neuronal network activity through tonic and phasic GABA activation.

  15. Brain size and thermoregulation during the evolution of the genus Homo.

    PubMed

    Naya, Daniel E; Naya, Hugo; Lessa, Enrique P

    2016-01-01

    Several hypotheses have been proposed to explain the evolution of an energetically costly brain in the genus Homo. Some of these hypotheses are based on the correlation between climatic factors and brain size recorded for this genus during the last millions of years. In this study, we propose a complementary climatic hypothesis that is based on the mechanistic connection between temperature, thermoregulation, and size of internal organs in endothermic species. We hypothesized that global cooling during the last 3.2 my may have imposed an increased energy expenditure for thermoregulation, which in the case of hominids could represent a driver for the evolution of an expanded brain, or at least, it could imply the relaxation of a negative selection pressure acting upon this costly organ. To test this idea, here we (1) assess variation in the energetic costs of thermoregulation and brain maintenance for the last 3.2 my, and (2) evaluate the relationship between Earth temperature and brain maintenance cost for the same period, taking into account the effects of body mass and fossil age. We found that: (1) the energetic cost associated with brain enlargement represents an important fraction (between 47.5% and 82.5%) of the increase in energy needed for thermoregulation; (2) fossil age is a better predictor of brain maintenance cost than Earth temperature, suggesting that (at least) another factor correlated with time was more relevant than ambient temperature in brain size evolution; and (3) there is a significant negative correlation between the energetic cost of brain and Earth temperature, even after accounting for the effect of body mass and fossil age. Thus, our results expand the current energetic framework for the study of brain size evolution in our lineage by suggesting that a fall in Earth temperature during the last millions of years may have facilitated brain enlargement.

  16. Effect of exposure to diazinon on adult rat's brain.

    PubMed

    Rashedinia, Marzieh; Hosseinzadeh, Hossein; Imenshahidi, Mohsen; Lari, Parisa; Razavi, Bibi Marjan; Abnous, Khalil

    2016-04-01

    Diazinon (DZN), a commonly used agricultural organophosphate insecticide, is one of the major concerns for human health. This study was planned to investigate neurotoxic effects of subacute exposure to DZN in adult male Wistar rats. Animals received corn oil as control and 15 and 30 mg/kg DZN orally by gastric gavage for 4 weeks. The cerebrum malondialdehyde and glutathione (GSH) contents were assessed as biomarkers of lipid peroxidation and nonenzyme antioxidants, respectively. Moreover, activated forms of caspase 3, -9, and Bax/Bcl-2 ratios were evaluated as key apoptotic proteins. Results of this study suggested that chronic administration of DZN did not change lipid peroxidation and GSH levels significantly in comparison with control. Also, the active forms of caspase 3 and caspase 9 were not significantly altered in DZN-treated rat groups. Moreover, no significant changes were observed in Bax and Bcl-2 ratios. This study indicated that generation of reactive oxygen species was probably modulated by intracellular antioxidant system. In conclusion, subacute oral administration of DZN did not alter lipid peroxidation. Moreover, apoptosis induction was not observed in rat brain.

  17. Comparative analysis of classic brain component sizes in relation to flightiness in birds.

    PubMed

    Symonds, Matthew R E; Weston, Michael A; Robinson, Randall W; Guay, Patrick-Jean

    2014-01-01

    Increased encephalization has been linked to a range of behavioural traits and scenarios. However, studies of whole brain size in this context have been criticised for ignoring the role of specific brain areas in controlling behaviour. In birds, the response to potential threats is one such behaviour that may relate to the way in which the brain processes sensory information. We used a phylogenetic generalised least squares (PGLS) analyses, based on five different phylogenetic hypotheses, to analyse the relationship of relative sizes of whole brain and brain components with Flight-Initiation Distance (FID), the distance at which birds flee from an approaching human, for 41 bird species. Starting distance (the distance at which an approach to a bird commences), body mass and eye size have elsewhere been shown to be positively associated with FID, and consequently were included as covariates in our analysis. Starting distance and body mass were by far the strongest predictors of FID. Of all brain components, cerebellum size had the strongest predictor weight and was negatively associated with FID but the confidence intervals on the average estimate included zero and the overall predictor weight was low. Models featuring individual brain components were generally more strongly weighted than models featuring whole brain size. The PGLS analyses estimated there to be no phylogenetic signal in the regression models, and hence produced results equivalent to ordinary least squares regression analysis. However analyses that assumed strong phylogenetic signal produced substantially different results with each phylogeny, and overall suggest a negative relationship between forebrain size and FID. Our analyses suggest that the evolutionary assumptions of the comparative analysis, and consideration of starting distance make a profound difference to the interpretation of the effect of brain components on FID in birds.

  18. Environmental enrichment is associated with rapid volumetric brain changes in adult mice.

    PubMed

    Scholz, Jan; Allemang-Grand, Rylan; Dazai, Jun; Lerch, Jason P

    2015-04-01

    Environmental enrichment is a model of increased structural brain plasticity. Previous histological observations have shown molecular and cellular changes in a few pre-determined areas of the rodent brain. However, little is known about the time course of enrichment-induced brain changes and how they distribute across the whole brain. Here we expose adult mice to three weeks of environmental enrichment using a novel re-configurable maze design. In-vivo MRI shows volumetric brain changes in brain areas related to spatial memory, navigation, and sensorimotor experience, such as the hippocampal formation and the sensorimotor cortex. Evidence from a second cohort of mice indicates that these plastic changes might occur as early as 24h after exposure. This suggests that novel experiences are powerful modulators of plasticity even in the adult brain. Understanding and harnessing the underlying molecular mechanisms could advance future treatments of neurological disease.

  19. Interleukin-6 gene (IL-6): a possible role in brain morphology in the healthy adult brain

    PubMed Central

    2012-01-01

    Background Cytokines such as interleukin 6 (IL-6) have been implicated in dual functions in neuropsychiatric disorders. Little is known about the genetic predisposition to neurodegenerative and neuroproliferative properties of cytokine genes. In this study the potential dual role of several IL-6 polymorphisms in brain morphology is investigated. Methodology In a large sample of healthy individuals (N = 303), associations between genetic variants of IL-6 (rs1800795; rs1800796, rs2069833, rs2069840) and brain volume (gray matter volume) were analyzed using voxel-based morphometry (VBM). Selection of single nucleotide polymorphisms (SNPs) followed a tagging SNP approach (e.g., Stampa algorigthm), yielding a capture 97.08% of the variation in the IL-6 gene using four tagging SNPs. Principal findings/results In a whole-brain analysis, the polymorphism rs1800795 (−174 C/G) showed a strong main effect of genotype (43 CC vs. 150 CG vs. 100 GG; x = 24, y = −10, z = −15; F(2,286) = 8.54, puncorrected = 0.0002; pAlphaSim-corrected = 0.002; cluster size k = 577) within the right hippocampus head. Homozygous carriers of the G-allele had significantly larger hippocampus gray matter volumes compared to heterozygous subjects. None of the other investigated SNPs showed a significant association with grey matter volume in whole-brain analyses. Conclusions/significance These findings suggest a possible neuroprotective role of the G-allele of the SNP rs1800795 on hippocampal volumes. Studies on the role of this SNP in psychiatric populations and especially in those with an affected hippocampus (e.g., by maltreatment, stress) are warranted. PMID:22695063

  20. Encoding of mechanical nociception differs in the adult and infant brain

    PubMed Central

    Fabrizi, Lorenzo; Verriotis, Madeleine; Williams, Gemma; Lee, Amy; Meek, Judith; Olhede, Sofia; Fitzgerald, Maria

    2016-01-01

    Newborn human infants display robust pain behaviour and specific cortical activity following noxious skin stimulation, but it is not known whether brain processing of nociceptive information differs in infants and adults. Imaging studies have emphasised the overlap between infant and adult brain connectome architecture, but electrophysiological analysis of infant brain nociceptive networks can provide further understanding of the functional postnatal development of pain perception. Here we hypothesise that the human infant brain encodes noxious information with different neuronal patterns compared to adults. To test this we compared EEG responses to the same time-locked noxious skin lance in infants aged 0–19 days (n = 18, clinically required) and adults aged 23–48 years (n = 21). Time-frequency analysis revealed that while some features of adult nociceptive network activity are present in infants at longer latencies, including beta-gamma oscillations, infants display a distinct, long latency, noxious evoked 18-fold energy increase in the fast delta band (2–4 Hz) that is absent in adults. The differences in activity between infants and adults have a widespread topographic distribution across the brain. These data support our hypothesis and indicate important postnatal changes in the encoding of mechanical pain in the human brain. PMID:27345331

  1. Selection for brain size impairs innate, but not adaptive immune responses

    PubMed Central

    Kotrschal, Alexander; Kolm, Niclas; Penn, Dustin J.

    2016-01-01

    Both the brain and the immune system are energetically demanding organs, and when natural selection favours increased investment into one, then the size or performance of the other should be reduced. While comparative analyses have attempted to test this potential evolutionary trade-off, the results remain inconclusive. To test this hypothesis, we compared the tissue graft rejection (an assay for measuring innate and acquired immune responses) in guppies (Poecilia reticulata) artificially selected for large and small relative brain size. Individual scales were transplanted between pairs of fish, creating reciprocal allografts, and the rejection reaction was scored over 8 days (before acquired immunity develops). Acquired immune responses were tested two weeks later, when the same pairs of fish received a second set of allografts and were scored again. Compared with large-brained animals, small-brained animals of both sexes mounted a significantly stronger rejection response to the first allograft. The rejection response to the second set of allografts did not differ between large- and small-brained fish. Our results show that selection for large brain size reduced innate immune responses to an allograft, which supports the hypothesis that there is a selective trade-off between investing into brain size and innate immunity. PMID:26962144

  2. Phenotypic integration of brain size and head morphology in Lake Tanganyika Cichlids

    PubMed Central

    2014-01-01

    Background Phenotypic integration among different anatomical parts of the head is a common phenomenon across vertebrates. Interestingly, despite centuries of research into the factors that contribute to the existing variation in brain size among vertebrates, little is known about the role of phenotypic integration in brain size diversification. Here we used geometric morphometrics on the morphologically diverse Tanganyikan cichlids to investigate phenotypic integration across key morphological aspects of the head. Then, while taking the effect of shared ancestry into account, we tested if head shape was associated with brain size while controlling for the potentially confounding effect of feeding strategy. Results The shapes of the anterior and posterior parts of the head were strongly correlated, indicating that the head represents an integrated morphological unit in Lake Tanganyika cichlids. After controlling for phylogenetic non-independence, we also found evolutionary associations between head shape, brain size and feeding ecology. Conclusions Geometric morphometrics and phylogenetic comparative analyses revealed that the anterior and posterior parts of the head are integrated, and that head morphology is associated with brain size and feeding ecology in Tanganyikan cichlid fishes. In light of previous results on mammals, our results suggest that the influence of phenotypic integration on brain diversification is a general process. PMID:24593160

  3. Regeneration of central cholinergic neurones in the adult rat brain.

    PubMed

    Svendgaard, N A; Björklund, A; Stenevi, U

    1976-01-30

    The regrowth of lesioned central acetylcholinesterase (AChE)-positive axons in the adult rat was studied in irides implanted to two different brain sites: in the caudal diencephalon and hippocampus, and in the hippocampal fimbria. At both implantation sites the cholinergic septo-hippocampal pathways were transected. At 2-4 weeks after lesion, newly formed, probably sprouting fibres could be followed in abundance from the lesioned proximal axon stumps into the iris transplant. Growth of newly formed AChE-positive fibres into the transplant was also observed from lesioned axons in the anterior thalamus, and to a minor extent also from the dorsal and ventral tegmental AChE-positive pathways and the habenulo-interpeduncular tract. The regrowth process of the sprouting AChE-positive, presumed cholinergic fibres into the iris target was studied in further detail in whole-mount preparations of the transplants. For this purpose the irides were removed from the brain, unfolded, spread out on microscope slides, and then stained for AChE. During the first 2-4 weeks after transplantation the sprouting central fibres grew out over large areas of the iris. The new fibres branched profusely into a terminal plexus that covered maximally about half of the iris surface, and in some areas the patterning of the regenerated central fibres mimicked closely that of the normal autonomic cholinergic innervation of the iris. In one series of experiments the AChE-staining was combined with fluorescence histochemical visualization of regenerated adrenergic fibres in the same specimens. In many areas there was a striking congruence in the distributional patterns of the regenerated central cholinergic and adrenergic fibres in the transplant. This indicates that - as in the normal iris - the sprouting cholinergic axons (primarily originating in the lesioned septo-hippocampal pathways) and adrenergic axons (primarily originating in the lesioned axons of the locus neurones) regenerate together

  4. Molecular Mechanism of Adult Neurogenesis and its Association with Human Brain Diseases

    PubMed Central

    Liu, He; Song, Ni

    2016-01-01

    Recent advances in neuroscience challenge the old dogma that neurogenesis occurs only during embryonic development. Mounting evidence suggests that functional neurogenesis occurs throughout adulthood. This review article discusses molecular factors that affect adult neurogenesis, including morphogens, growth factors, neurotransmitters, transcription factors, and epigenetic factors. Furthermore, we summarize and compare current evidence of associations between adult neurogenesis and human brain diseases such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and brain tumors. PMID:27375363

  5. Molecular Mechanism of Adult Neurogenesis and its Association with Human Brain Diseases.

    PubMed

    Liu, He; Song, Ni

    2016-01-01

    Recent advances in neuroscience challenge the old dogma that neurogenesis occurs only during embryonic development. Mounting evidence suggests that functional neurogenesis occurs throughout adulthood. This review article discusses molecular factors that affect adult neurogenesis, including morphogens, growth factors, neurotransmitters, transcription factors, and epigenetic factors. Furthermore, we summarize and compare current evidence of associations between adult neurogenesis and human brain diseases such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and brain tumors. PMID:27375363

  6. Recovery from Mild Traumatic Brain Injury in Previously Healthy Adults.

    PubMed

    Losoi, Heidi; Silverberg, Noah D; Wäljas, Minna; Turunen, Senni; Rosti-Otajärvi, Eija; Helminen, Mika; Luoto, Teemu M; Julkunen, Juhani; Öhman, Juha; Iverson, Grant L

    2016-04-15

    This prospective longitudinal study reports recovery from mild traumatic brain injury (MTBI) across multiple domains in a carefully selected consecutive sample of 74 previously healthy adults. The patients with MTBI and 40 orthopedic controls (i.e., ankle injuries) completed assessments at 1, 6, and 12 months after injury. Outcome measures included cognition, post-concussion symptoms, depression, traumatic stress, quality of life, satisfaction with life, resilience, and return to work. Patients with MTBI reported more post-concussion symptoms and fatigue than the controls at the beginning of recovery, but by 6 months after injury, did not differ as a group from nonhead injury trauma controls on cognition, fatigue, or mental health, and by 12 months, their level of post-concussion symptoms and quality of life was similar to that of controls. Almost all (96%) patients with MTBI returned to work/normal activities (RTW) within the follow-up of 1 year. A subgroup of those with MTBIs and controls reported mild post-concussion-like symptoms at 1 year. A large percentage of the subgroup who had persistent symptoms had a modifiable psychological risk factor at 1 month (i.e., depression, traumatic stress, and/or low resilience), and at 6 months, they had greater post-concussion symptoms, fatigue, insomnia, traumatic stress, and depression, and worse quality of life. All of the control subjects who had mild post-concussion-like symptoms at 12 months also had a mental health problem (i.e., depression, traumatic stress, or both). This illustrates the importance of providing evidence-supported treatment and rehabilitation services early in the recovery period.

  7. Monte Carlo simulation of light propagation in the adult brain

    NASA Astrophysics Data System (ADS)

    Mudra, Regina M.; Nadler, Andreas; Keller, Emanuella; Niederer, Peter

    2004-06-01

    When near infrared spectroscopy (NIRS) is applied noninvasively to the adult head for brain monitoring, extra-cerebral bone and surface tissue exert a substantial influence on the cerebral signal. Most attempts to subtract extra-cerebral contamination involve spatially resolved spectroscopy (SRS). However, inter-individual variability of anatomy restrict the reliability of SRS. We simulated the light propagation with Monte Carlo techniques on the basis of anatomical structures determined from 3D-magnetic resonance imaging (MRI) exhibiting a voxel resolution of 0.8 x 0.8 x 0.8 mm3 for three different pairs of T1/T2 values each. The MRI data were used to define the material light absorption and dispersion coefficient for each voxel. The resulting spatial matrix was applied in the Monte Carlo Simulation to determine the light propagation in the cerebral cortex and overlaying structures. The accuracy of the Monte Carlo Simulation was furthermore increased by using a constant optical path length for the photons which was less than the median optical path length of the different materials. Based on our simulations we found a differential pathlength factor (DPF) of 6.15 which is close to with the value of 5.9 found in the literature for a distance of 4.5cm between the external sensors. Furthermore, we weighted the spatial probability distribution of the photons within the different tissues with the probabilities of the relative blood volume within the tissue. The results show that 50% of the NIRS signal is determined by the grey matter of the cerebral cortex which allows us to conclude that NIRS can produce meaningful cerebral blood flow measurements providing that the necessary corrections for extracerebral contamination are included.

  8. Lifetime selection on adult body size and components of body size in a waterstrider: opposing selection and maintenance of sexual size dimorphism.

    PubMed

    Preziosi, R F; Fairbairn, D J

    2000-04-01

    Sexual size dimorphism (SSD), the difference in body size between males and females, is common in almost all taxa of animals and is generally assumed to be adaptive. Although sexual selection and fecundity selection alone have often been invoked to explain the evolution of SSD, more recent views indicate that the sexes must experience different lifetime selection pressures for SSD to evolve and be maintained. We estimated selection acting on male and female adult body size (total length) and components of body size in the waterstrider Aquarius remigis during three phases of life history. Opposing selection pressures for overall body size occurred in separate episodes of fitness for females in both years and for males in one year. Specific components of body size were often the targets of the selection on overall body size. When net adult fitness was estimated by combining each individual's fitnesses from all episodes, we found stabilizing selection in both sexes. In addition, the net optimum overall body size of males was smaller than that of females. However, even when components of body size had experienced opposing selection pressures in individual episodes, no components appeared to be under lifetime stabilizing selection. This is the first evidence that contemporary selection in a natural population acts to maintain female size larger than male size, the most common pattern of SSD in nature.

  9. Prenatal famine exposure has sex-specific effects on brain size.

    PubMed

    de Rooij, Susanne R; Caan, Matthan W A; Swaab, Dick F; Nederveen, Aart J; Majoie, Charles B; Schwab, Matthias; Painter, Rebecca C; Roseboom, Tessa J

    2016-08-01

    Early nutritional deprivation might cause irreversible damage to the brain. Prenatal exposure to undernutrition has been shown to be associated with increased central nervous system anomalies at birth and decreased cognitive function in adulthood. Little is known about the potential effect on the brain in older age. We investigated brain size and structure at age 68 years after prenatal famine exposure. T1-weighted structural magnetic resonance images of the brain were made in 118 Dutch famine birth cohort members. Of these 118 (44% male, age range 65-69 years), 41 had been exposed to famine in early gestation and 77 had been prenatally unexposed. Structural volumes were automatically assessed using FreeSurfer. Diffusion tensor imaging was performed and anisotropy and diffusivity were computed. Fluid attenuated inversion recovery was performed to assess white matter hyperintensities. Exposure to famine in early gestation was associated with smaller intracranial volume in males, but not females. Volumes of total brain, grey and white matter were also smaller in early exposed males, but these differences disappeared after adjusting for intracranial volume. Prenatally exposed males but not females, had a smaller intracranial and total brain volume compared to unexposed subjects. Our findings show that prenatal undernutrition permanently affected brain size.media-1vid110.1093/brain/aww132_video_abstractaww132_video_abstract.

  10. Prenatal famine exposure has sex-specific effects on brain size.

    PubMed

    de Rooij, Susanne R; Caan, Matthan W A; Swaab, Dick F; Nederveen, Aart J; Majoie, Charles B; Schwab, Matthias; Painter, Rebecca C; Roseboom, Tessa J

    2016-08-01

    Early nutritional deprivation might cause irreversible damage to the brain. Prenatal exposure to undernutrition has been shown to be associated with increased central nervous system anomalies at birth and decreased cognitive function in adulthood. Little is known about the potential effect on the brain in older age. We investigated brain size and structure at age 68 years after prenatal famine exposure. T1-weighted structural magnetic resonance images of the brain were made in 118 Dutch famine birth cohort members. Of these 118 (44% male, age range 65-69 years), 41 had been exposed to famine in early gestation and 77 had been prenatally unexposed. Structural volumes were automatically assessed using FreeSurfer. Diffusion tensor imaging was performed and anisotropy and diffusivity were computed. Fluid attenuated inversion recovery was performed to assess white matter hyperintensities. Exposure to famine in early gestation was associated with smaller intracranial volume in males, but not females. Volumes of total brain, grey and white matter were also smaller in early exposed males, but these differences disappeared after adjusting for intracranial volume. Prenatally exposed males but not females, had a smaller intracranial and total brain volume compared to unexposed subjects. Our findings show that prenatal undernutrition permanently affected brain size.media-1vid110.1093/brain/aww132_video_abstractaww132_video_abstract. PMID:27401522

  11. Correlates of Depression in Adult Siblings of Persons with Traumatic Brain Injury

    ERIC Educational Resources Information Center

    Degeneffe, Charles Edmund; Lynch, Ruth Torkelson

    2006-01-01

    Using Pearlin's stress process model, this study examined correlates of depression in 170 adult siblings of persons with traumatic brain injury (TBI). Approximately 39% of adult sibling participants evinced "Center for Epidemiologic Studies-Depression" (CES-D; Radloff, 1977) scores indicating clinically significant depressive symptoms. Background…

  12. Development of a Conceptual Model to Predict Physical Activity Participation in Adults with Brain Injuries

    ERIC Educational Resources Information Center

    Driver, Simon

    2008-01-01

    The purpose was to examine psychosocial factors that influence the physical activity behaviors of adults with brain injuries. Two differing models, based on Harter's model of self-worth, were proposed to examine the relationship between perceived competence, social support, physical self-worth, affect, and motivation. Adults numbering 384 with…

  13. Cognitive function and brain structure after recurrent mild traumatic brain injuries in young-to-middle-aged adults

    PubMed Central

    List, Jonathan; Ott, Stefanie; Bukowski, Martin; Lindenberg, Robert; Flöel, Agnes

    2015-01-01

    Recurrent mild traumatic brain injuries (mTBIs) are regarded as an independent risk factor for developing dementia in later life. We here aimed to evaluate associations between recurrent mTBIs, cognition, and gray matter volume and microstructure as revealed by structural magnetic resonance imaging (MRI) in the chronic phase after mTBIs in young adulthood. We enrolled 20 young-to-middle-aged subjects, who reported two or more sports-related mTBIs, with the last mTBI > 6 months prior to study enrolment (mTBI group), and 21 age-, sex- and education matched controls with no history of mTBI (control group). All participants received comprehensive neuropsychological testing, and high resolution T1-weighted and diffusion tensor MRI in order to assess cortical thickness (CT) and microstructure, hippocampal volume, and ventricle size. Compared to the control group, subjects of the mTBI group presented with lower CT within the right temporal lobe and left insula using an a priori region of interest approach. Higher number of mTBIs was associated with lower CT in bilateral insula, right middle temporal gyrus and right entorhinal area. Our results suggest persistent detrimental effects of recurrent mTBIs on CT already in young-to-middle-aged adults. If additional structural deterioration occurs during aging, subtle neuropsychological decline may progress to clinically overt dementia earlier than in age-matched controls, a hypothesis to be assessed in future prospective trials. PMID:26052275

  14. An insulin-like peptide regulates size and adult stem cells in planarians.

    PubMed

    Miller, Claire M; Newmark, Phillip A

    2012-01-01

    Animal growth depends on nutritional intake during development. In many animals, nutritional status is uncoupled from moderation of adult stature after adult size is achieved. However, some long-lived animals continue to regulate adult size and fertility in a nutrition-dependent manner. For example, the regenerating flatworm Schmidtea mediterranea becomes smaller, or degrows, during periods of starvation. These animals provide an opportunity to readily observe adult stem cell population dynamics in response to nutritional cues. We explored the role of insulin signaling in S. mediterranea. We disrupted insulin signaling via RNA interference and showed that animals, despite eating, degrew similarly to starved animals. Utilizing in situ hybridization and immunofluorescence, we assessed cellular changes in proliferative populations including the planarian adult stem cell population (neoblasts) and the germline. Both impaired insulin signaling and nutritional deprivation correlated with decreased neoblast proliferation. Additionally, insulin signaling played a role in supporting spermatogenesis that was distinct from the effects of starvation. In sum, we have demonstrated that insulin signaling is responsible for regulation of adult animal size and tissue homeostasis in an organism with plastic adult size. Importantly, insulin signaling continued to affect stem cell and germline populations in a mature organism. Furthermore, we have shown that adult organisms can differentially regulate specific cell populations as a result of environmental challenges.

  15. The Social Environment and Neurogenesis in the Adult Mammalian Brain

    PubMed Central

    Lieberwirth, Claudia; Wang, Zuoxin

    2012-01-01

    Adult neurogenesis – the formation of new neurons in adulthood – has been shown to be modulated by a variety of endogenous (e.g., trophic factors, neurotransmitters, and hormones) as well as exogenous (e.g., physical activity and environmental complexity) factors. Research on exogenous regulators of adult neurogenesis has focused primarily on the non-social environment. More recently, however, evidence has emerged suggesting that the social environment can also affect adult neurogenesis. The present review details the effects of adult–adult (e.g., mating and chemosensory interactions) and adult–offspring (e.g., gestation, parenthood, and exposure to offspring) interactions on adult neurogenesis. In addition, the effects of a stressful social environment (e.g., lack of social support and dominant–subordinate interactions) on adult neurogenesis are reviewed. The underlying hormonal mechanisms and potential functional significance of adult-generated neurons in mediating social behaviors are also discussed. PMID:22586385

  16. Rearing-group size determines social competence and brain structure in a cooperatively breeding cichlid.

    PubMed

    Fischer, Stefan; Bessert-Nettelbeck, Mathilde; Kotrschal, Alexander; Taborsky, Barbara

    2015-07-01

    Social animals can greatly benefit from well-developed social skills. Because the frequency and diversity of social interactions often increase with the size of social groups, the benefits of advanced social skills can be expected to increase with group size. Variation in social skills often arises during ontogeny, depending on early social experience. Whether variation of social-group sizes affects development of social skills and related changes in brain structures remains unexplored. We investigated whether, in a cooperatively breeding cichlid, early group size (1) shapes social behavior and social skills and (2) induces lasting plastic changes in gross brain structures and (3) whether the development of social skills is confined to a sensitive ontogenetic period. Rearing-group size and the time juveniles spent in these groups interactively influenced the development of social skills and the relative sizes of four main brain regions. We did not detect a sensitive developmental period for the shaping of social behavior within the 2-month experience phase. Instead, our results suggest continuous plastic behavioral changes over time. We discuss how developmental effects on social behavior and brain architecture may adaptively tune phenotypes to their current or future environments. PMID:26098344

  17. Sample sizes for brain atrophy outcomes in trials for secondary progressive multiple sclerosis

    PubMed Central

    Altmann, D R.; Jasperse, B; Barkhof, F; Beckmann, K; Filippi, M; Kappos, L D.; Molyneux, P; Polman, C H.; Pozzilli, C; Thompson, A J.; Wagner, K; Yousry, T A.; Miller, D H.

    2009-01-01

    Background: Progressive brain atrophy in multiple sclerosis (MS) may reflect neuroaxonal and myelin loss and MRI measures of brain tissue loss are used as outcome measures in MS treatment trials. This study investigated sample sizes required to demonstrate reduction of brain atrophy using three outcome measures in a parallel group, placebo-controlled trial for secondary progressive MS (SPMS). Methods: Data were taken from a cohort of 43 patients with SPMS who had been followed up with 6-monthly T1-weighted MRI for up to 3 years within the placebo arm of a therapeutic trial. Central cerebral volumes (CCVs) were measured using a semiautomated segmentation approach, and brain volume normalized for skull size (NBV) was measured using automated segmentation (SIENAX). Change in CCV and NBV was measured by subtraction of baseline from serial CCV and SIENAX images; in addition, percentage brain volume change relative to baseline was measured directly using a registration-based method (SIENA). Sample sizes for given treatment effects and power were calculated for standard analyses using parameters estimated from the sample. Results: For a 2-year trial duration, minimum sample sizes per arm required to detect a 50% treatment effect at 80% power were 32 for SIENA, 69 for CCV, and 273 for SIENAX. Two-year minimum sample sizes were smaller than 1-year by 71% for SIENAX, 55% for CCV, and 44% for SIENA. Conclusion: SIENA and central cerebral volume are feasible outcome measures for inclusion in placebo-controlled trials in secondary progressive multiple sclerosis. GLOSSARY ANCOVA = analysis of covariance; CCV = central cerebral volume; FSL = FMRIB Software Library; MNI = Montreal Neurological Institute; MS = multiple sclerosis; NBV = normalized brain volume; PBVC = percent brain volume change; RRMS = relapsing–remitting multiple sclerosis; SPMS = secondary progressive multiple sclerosis. PMID:19005170

  18. Cerebroventricular Microinjection (CVMI) into Adult Zebrafish Brain Is an Efficient Misexpression Method for Forebrain Ventricular Cells

    PubMed Central

    Kizil, Caghan; Brand, Michael

    2011-01-01

    The teleost fish Danio rerio (zebrafish) has a remarkable ability to generate newborn neurons in its brain at adult stages of its lifespan-a process called adult neurogenesis. This ability relies on proliferating ventricular progenitors and is in striking contrast to mammalian brains that have rather restricted capacity for adult neurogenesis. Therefore, investigating the zebrafish brain can help not only to elucidate the molecular mechanisms of widespread adult neurogenesis in a vertebrate species, but also to design therapies in humans with what we learn from this teleost. Yet, understanding the cellular behavior and molecular programs underlying different biological processes in the adult zebrafish brain requires techniques that allow manipulation of gene function. As a complementary method to the currently used misexpression techniques in zebrafish, such as transgenic approaches or electroporation-based delivery of DNA, we devised a cerebroventricular microinjection (CVMI)-assisted knockdown protocol that relies on vivo morpholino oligonucleotides, which do not require electroporation for cellular uptake. This rapid method allows uniform and efficient knockdown of genes in the ventricular cells of the zebrafish brain, which contain the neurogenic progenitors. We also provide data on the use of CVMI for growth factor administration to the brain – in our case FGF8, which modulates the proliferation rate of the ventricular cells. In this paper, we describe the CVMI method and discuss its potential uses in zebrafish. PMID:22076157

  19. Adolescent binge ethanol treatment alters adult brain regional volumes, cortical extracellular matrix protein and behavioral flexibility

    PubMed Central

    Coleman, Leon Garland; Liu, Wen; Oguz, Ipek; Styner, Martin; Crews, Fulton T.

    2014-01-01

    Adolescents binge drink more than any other age group, increasing risk of disrupting the development of the frontal cortex. We hypothesized that adolescent binge drinking would lead to persistent alterations in adulthood. In this study, we modeled adolescent weekend underage binge-drinking, using adolescent mice (post-natal days [P] 28–37). The adolescent intermittent binge ethanol (AIE) treatment includes 6 binge intragastric doses of ethanol in an intermittent pattern across adolescence. Assessments were conducted in adulthood following extended abstinence to determine if there were persistent changes in adults. Reversal learning, open field and other behavioral assessments as well as brain structure using magnetic imaging and immunohistochemistry were determined. We found AIE did not impact adult Barnes Maze learning. However, AIE did cause reversal learning deficits in adults. AIE also caused structural changes in the adult brain. AIE was associated with adulthood volume enlargements in specific brain regions without changes in total brain volume. Enlarged regions included the orbitofrontal cortex (OFC, 4%), cerebellum (4.5%), thalamus (2%), internal capsule (10%) and genu of the corpus callosum (7%). The enlarged OFC volume in adults after AIE is consistent with previous imaging studies in human adolescents. AIE treatment was associated with significant increases in the expression of several extracellular matrix (ECM) proteins in the adult OFC including WFA (55%), Brevican (32%), Neurocan (105%), Tenacin-C (25%), and HABP (5%). These findings are consistent with AIE causing persistent changes in brain structure that could contribute to a lack of behavioral flexibility. PMID:24275185

  20. Control of adult neurogenesis by programmed cell death in the mammalian brain.

    PubMed

    Ryu, Jae Ryun; Hong, Caroline Jeeyeon; Kim, Joo Yeon; Kim, Eun-Kyoung; Sun, Woong; Yu, Seong-Woon

    2016-04-21

    The presence of neural stem cells (NSCs) and the production of new neurons in the adult brain have received great attention from scientists and the public because of implications to brain plasticity and their potential use for treating currently incurable brain diseases. Adult neurogenesis is controlled at multiple levels, including proliferation, differentiation, migration, and programmed cell death (PCD). Among these, PCD is the last and most prominent process for regulating the final number of mature neurons integrated into neural circuits. PCD can be classified into apoptosis, necrosis, and autophagic cell death and emerging evidence suggests that all three may be important modes of cell death in neural stem/progenitor cells. However, the molecular mechanisms that regulate PCD and thereby impact the intricate balance between self-renewal, proliferation, and differentiation during adult neurogenesis are not well understood. In this comprehensive review, we focus on the extent, mechanism, and biological significance of PCD for the control of adult neurogenesis in the mammalian brain. The role of intrinsic and extrinsic factors in the regulation of PCD at the molecular and systems levels is also discussed. Adult neurogenesis is a dynamic process, and the signals for differentiation, proliferation, and death of neural progenitor/stem cells are closely interrelated. A better understanding of how adult neurogenesis is influenced by PCD will help lead to important insights relevant to brain health and diseases.

  1. Age-Related Differences in the Brain Areas outside the Classical Language Areas among Adults Using Category Decision Task

    ERIC Educational Resources Information Center

    Cho, Yong Won; Song, Hui-Jin; Lee, Jae Jun; Lee, Joo Hwa; Lee, Hui Joong; Yi, Sang Doe; Chang, Hyuk Won; Berl, Madison M.; Gaillard, William D.; Chang, Yongmin

    2012-01-01

    Older adults perform much like younger adults on language. This similar level of performance, however, may come about through different underlying brain processes. In the present study, we evaluated age-related differences in the brain areas outside the typical language areas among adults using a category decision task. Our results showed that…

  2. PDYN, a gene implicated in brain/mental disorders, is targeted by REST in the adult human brain.

    PubMed

    Henriksson, Richard; Bäckman, Cristina M; Harvey, Brandon K; Kadyrova, Helena; Bazov, Igor; Shippenberg, Toni S; Bakalkin, Georgy

    2014-11-01

    The dynorphin κ-opioid receptor system is implicated in mental health and brain/mental disorders. However, despite accumulating evidence that PDYN and/or dynorphin peptide expression is altered in the brain of individuals with brain/mental disorders, little is known about transcriptional control of PDYN in humans. In the present study, we show that PDYN is targeted by the transcription factor REST in human neuroblastoma SH-SY5Y cells and that that interfering with REST activity increases PDYN expression in these cells. We also show that REST binding to PDYN is reduced in the adult human brain compared to SH-SY5Y cells, which coincides with higher PDYN expression. This may be related to MIR-9 mediated down-regulation of REST as suggested by a strong inverse correlation between REST and MIR-9 expression. Our results suggest that REST represses PDYN expression in SH-SY5Y cells and the adult human brain and may have implications for mental health and brain/mental disorders. PMID:25220237

  3. Essential role of brain-derived neurotrophic factor in adult hippocampal function

    PubMed Central

    Monteggia, Lisa M.; Barrot, Michel; Powell, Craig M.; Berton, Olivier; Galanis, Victor; Gemelli, Terry; Meuth, Sven; Nagy, Andreas; Greene, Robert W.; Nestler, Eric J.

    2004-01-01

    Brain-derived neurotrophic factor (BDNF) regulates neuronal development and function. However, it has been difficult to discern its role in the adult brain in influencing complex behavior. Here, we use a recently developed inducible knockout system to show that deleting BDNF in broad forebrain regions of adult mice impairs hippocampal-dependent learning and long-term potentiation. We use the inducible nature of this system to show that the loss of BDNF during earlier stages of development causes hyperactivity and more pronounced hippocampal-dependent learning deficits. We also demonstrate that the loss of forebrain BDNF attenuates the actions of desipramine, an antidepressant, in the forced swim test, suggesting the involvement of BDNF in antidepressant efficacy. These results establish roles for BDNF in the adult, and demonstrate the strength of this inducible knockout system in studying gene function in the adult brain. PMID:15249684

  4. Birth weight, early life course BMI, and body size change: Chains of risk to adult inflammation?

    PubMed

    Goosby, Bridget J; Cheadle, Jacob E; McDade, Thomas

    2016-01-01

    This paper examines how body size changes over the early life course to predict high sensitivity C-reactive protein in a U.S. based sample. Using three waves of the National Longitudinal Study of Adolescent Health (Add Health), we test the chronic disease epidemiological models of fetal origins, sensitive periods, and chains of risk from birth into adulthood. Few studies link birth weight and changes in obesity status over adolescence and early adulthood to adult obesity and inflammation. Consistent with fetal origins and sensitive periods hypotheses, body size and obesity status at each developmental period, along with increasing body size between periods, are highly correlated with adult CRP. However, the predictive power of earlier life course periods is mediated by body size and body size change at later periods in a pattern consistent with the chains of risk model. Adult increases in obesity had effect sizes of nearly 0.3 sd, and effect sizes from overweight to the largest obesity categories were between 0.3 and 1 sd. There was also evidence that risk can be offset by weight loss, which suggests that interventions can reduce inflammation and cardiovascular risk, that females are more sensitive to body size changes, and that body size trajectories over the early life course account for African American- and Hispanic-white disparities in adult inflammation.

  5. Restricted nature of adult neural stem cells: re-evaluation of their potential for brain repair

    PubMed Central

    Obernier, Kirsten; Tong, Cheuk Ka; Alvarez-Buylla, Arturo

    2014-01-01

    Neural stem cells (NSCs) in the walls of the lateral ventricles continue to produce new neurons and oligodendrocytes throughout life. The identification of NSCs, long-range neuronal migration, and the integration of new neurons into fully formed mature neural circuits—all in the juvenile or adult brain—has dramatically changed concepts in neurodevelopment and suggests new strategies for brain repair. Yet, the latter has to be seen in perspective: NSCs in the adult are heterogeneous and highly regionally specified; young neurons derived from these primary progenitors migrate and integrate in specific brain regions. Neurogenesis appears to have a function in brain plasticity rather than brain repair. If similar processes could be induced in regions of the brain that are normally not a target of new neurons, therapeutic neuronal replacement may one day reinstate neural circuit plasticity and possibly repair broken neural circuits. PMID:24987325

  6. Stature, body mass, and brain size: a two-million-year odyssey.

    PubMed

    Gallagher, Andrew

    2013-12-01

    Physical size has been critical in the evolutionary success of the genus Homo over the past 2.4 million-years. An acceleration in the expansion of savannah grasslands in Africa from 1.6Ma to 1.2Ma witnessed concomitant increases in physical stature (150-170cm), weight (50-70kg), and brain size (750-900cm(3)). With the onset of 100,000year Middle Pleistocene glacial cycles ("ice ages") some 780,000years ago, large-bodied Homo groups had reached modern size and had successfully dispersed from equatorial Africa, Central, and Southeast Asia to high-latitude localities in Atlantic Europe and North East Asia. While there is support for incursions of multiple Homo lineages to West Asia and Continental Europe at this time, data does not favour a persistence of Homo erectus beyond ∼400,000years ago in Africa, west and Central Asia, and Europe. Novel Middle Pleistocene Homo forms (780,000-400,000years) may not have been substantially taller (150-170cm) than earlier Homo (1.6Ma-800,000years), yet brain size exceeded 1000cm(3) and body mass approached 80kg in some males. Later Pleistocene Homo (400,000-138,000years) were 'massive' in their height (160-190cm) and mass (70-90kg) and consistently exceed recent humans. Relative brain size exceeds earlier Homo, yet is substantially lower than in final glacial H. sapiens and Homo neanderthalensis. A final leap in absolute and relative brain size in Homo (300,000-138,000years) occurred independent of any observed increase in body mass and implies a different selective mediator to that operating on brain size increases observed in earlier Homo. PMID:23562520

  7. Sex, stress and the brain: interactive actions of hormones on the developing and adult brain.

    PubMed

    McEwen, B S

    2014-12-01

    The brain is a target of steroid hormone actions that affect brain architecture, molecular and neurochemical processes, behavior and neuroprotection via both genomic and non-genomic actions. Estrogens have such effects throughout the brain and this article provides an historical and current view of how this new view has come about and how it has affected the study of sex differences, as well as other areas of neuroscience, including the effects of stress on the brain.

  8. Structural alterations of brain grey and white matter in early deaf adults.

    PubMed

    Hribar, Manja; Suput, Dušan; Carvalho, Altiere Araujo; Battelino, Saba; Vovk, Andrej

    2014-12-01

    Functional and structural brain alterations in the absence of the auditory input have been described, but the observed structural brain changes in the deaf are not uniform. Some of the previous researchers focused only on the auditory areas, while others investigated the whole brain or other selected regions of interest. Majority of studies revealed decreased white matter (WM) volume or altered WM microstructure and preserved grey matter (GM) structure of the auditory areas in the deaf. However, preserved WM and increased or decreased GM volume of the auditory areas in the deaf have also been reported. Several structural alterations in the deaf were found also outside the auditory areas, but these regions differ between the studies. The observed differences between the studies could be due to the use of different single-analysis techniques, or the diverse population sample and its size, or possibly due to the usage of hearing aids by some participating deaf subjects. To overcome the aforementioned limitations four different image-processing techniques were used to investigate changes in the brain morphology of prelingually deaf adults who have never used hearing aids. GM and WM volume of the Heschl's gyrus (HG) were measured using manual volumetry, while whole brain GM volume, thickness and surface area were assessed by voxel-based morphometry (VBM) and surface-based analysis. The microstructural properties of the WM were evaluated by diffusion tensor imaging (DTI). The data were compared between 14 congenitally deaf adults and 14 sex- and age-matched normal hearing controls. Manual volumetry revealed preserved GM volume of the bilateral HG and significantly decreased WM volume of the left HG in the deaf. VBM showed increased cerebellar GM volume in the deaf, while no statistically significant differences were observed in the GM thickness or surface area between the groups. The results of the DTI analysis showed WM microstructural alterations between the groups in

  9. The effect of practical portion size measurement aids on the accuracy of portion size estimates made by young adults.

    PubMed

    Byrd-Bredbenner, C; Schwartz, J

    2004-08-01

    A barrier to controlling the amount of food consumed may be the difficulty consumers have in accurately estimating portion sizes. Although portion size measurement aids (PSMAs) can improve estimation accuracy, their bulk and/or cost tends to make them impractical for regular use. The purpose of this study was to investigate the effect on portion size estimation accuracy of two practical PSMAs: a 2-D PSMA (life size picture of tennis and golf balls) and 3-D PSMAs (tennis and golf balls). Young adults were randomly assigned to one of two groups and estimated the portion sizes of 36 foods divided into three equal sets. PSMAs were not used to estimate portion sizes in Food Set 1. Study group 1 (n = 57) used the 2-D PSMA and study group 2 (n = 56) used the 3-D PSMAs to estimate the portion sizes in Food Set 2. Neither group used PSMAs to estimate portion sizes in Food Set 3. Repeated measures anova indicated that both groups significantly improved estimation accuracy between Food Sets 1 and 2 and between Foods Sets 1 and 3. Thus, even short-term exposure to practical PSMAs may improve estimation accuracy and these improvements persist when the PSMA is no longer available. However, the accuracy rate for Food Set 2 was only about 60% indicating that a great deal of estimation error remains. PMID:15250844

  10. High-resolution gene expression atlases for adult and developing mouse brain and spinal cord.

    PubMed

    Henry, Alex M; Hohmann, John G

    2012-10-01

    Knowledge of the structure, genetics, circuits, and physiological properties of the mammalian brain in both normal and pathological states is ever increasing as research labs worldwide probe the various aspects of brain function. Until recently, however, comprehensive cataloging of gene expression across the central nervous system has been lacking. The Allen Institute for Brain Science, as part of its mission to propel neuroscience research, has completed several large gene-mapping projects in mouse, nonhuman primate, and human brain, producing informative online public resources and tools. Here we present the Allen Mouse Brain Atlas, covering ~20,000 genes throughout the adult mouse brain; the Allen Developing Mouse Brain Atlas, detailing expression of approximately 2,000 important developmental genes across seven embryonic and postnatal stages of brain growth; and the Allen Spinal Cord Atlas, revealing expression for ~20,000 genes in the adult and neonatal mouse spinal cords. Integrated data-mining tools, including reference atlases, informatics analyses, and 3-D viewers, are described. For these massive-scale projects, high-throughput industrial techniques were developed to standardize and reliably repeat experimental goals. To verify consistency and accuracy, a detailed analysis of the 1,000 most viewed genes for the adult mouse brain (according to website page views) was performed by comparing our data with peer-reviewed literature and other databases. We show that our data are highly consistent with independent sources and provide a comprehensive compendium of information and tools used by thousands of researchers each month. All data and tools are freely available via the Allen Brain Atlas portal (www.brain-map.org).

  11. BDNF Expression in Larval and Adult Zebrafish Brain: Distribution and Cell Identification

    PubMed Central

    Cacialli, Pietro; Gueguen, Marie-Madeleine; Coumailleau, Pascal; D’Angelo, Livia; Kah, Olivier; Lucini, Carla; Pellegrini, Elisabeth

    2016-01-01

    Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, has emerged as an active mediator in many essential functions in the central nervous system of mammals. BDNF plays significant roles in neurogenesis, neuronal maturation and/or synaptic plasticity and is involved in cognitive functions such as learning and memory. Despite the vast literature present in mammals, studies devoted to BDNF in the brain of other animal models are scarse. Zebrafish is a teleost fish widely known for developmental genetic studies and is emerging as model for translational neuroscience research. In addition, its brain shows many sites of adult neurogenesis allowing higher regenerative properties after traumatic injuries. To add further knowledge on neurotrophic factors in vertebrate brain models, we decided to determine the distribution of bdnf mRNAs in the larval and adult zebrafish brain and to characterize the phenotype of cells expressing bdnf mRNAs by means of double staining studies. Our results showed that bdnf mRNAs were widely expressed in the brain of 7 days old larvae and throughout the whole brain of mature female and male zebrafish. In adults, bdnf mRNAs were mainly observed in the dorsal telencephalon, preoptic area, dorsal thalamus, posterior tuberculum, hypothalamus, synencephalon, optic tectum and medulla oblongata. By combining immunohistochemistry with in situ hybridization, we showed that bdnf mRNAs were never expressed by radial glial cells or proliferating cells. By contrast, bdnf transcripts were expressed in cells with neuronal phenotype in all brain regions investigated. Our results provide the first demonstration that the brain of zebrafish expresses bdnf mRNAs in neurons and open new fields of research on the role of the BDNF factor in brain mechanisms in normal and brain repairs situations. PMID:27336917

  12. BDNF Expression in Larval and Adult Zebrafish Brain: Distribution and Cell Identification.

    PubMed

    Cacialli, Pietro; Gueguen, Marie-Madeleine; Coumailleau, Pascal; D'Angelo, Livia; Kah, Olivier; Lucini, Carla; Pellegrini, Elisabeth

    2016-01-01

    Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, has emerged as an active mediator in many essential functions in the central nervous system of mammals. BDNF plays significant roles in neurogenesis, neuronal maturation and/or synaptic plasticity and is involved in cognitive functions such as learning and memory. Despite the vast literature present in mammals, studies devoted to BDNF in the brain of other animal models are scarse. Zebrafish is a teleost fish widely known for developmental genetic studies and is emerging as model for translational neuroscience research. In addition, its brain shows many sites of adult neurogenesis allowing higher regenerative properties after traumatic injuries. To add further knowledge on neurotrophic factors in vertebrate brain models, we decided to determine the distribution of bdnf mRNAs in the larval and adult zebrafish brain and to characterize the phenotype of cells expressing bdnf mRNAs by means of double staining studies. Our results showed that bdnf mRNAs were widely expressed in the brain of 7 days old larvae and throughout the whole brain of mature female and male zebrafish. In adults, bdnf mRNAs were mainly observed in the dorsal telencephalon, preoptic area, dorsal thalamus, posterior tuberculum, hypothalamus, synencephalon, optic tectum and medulla oblongata. By combining immunohistochemistry with in situ hybridization, we showed that bdnf mRNAs were never expressed by radial glial cells or proliferating cells. By contrast, bdnf transcripts were expressed in cells with neuronal phenotype in all brain regions investigated. Our results provide the first demonstration that the brain of zebrafish expresses bdnf mRNAs in neurons and open new fields of research on the role of the BDNF factor in brain mechanisms in normal and brain repairs situations. PMID:27336917

  13. High-resolution gene expression atlases for adult and developing mouse brain and spinal cord.

    PubMed

    Henry, Alex M; Hohmann, John G

    2012-10-01

    Knowledge of the structure, genetics, circuits, and physiological properties of the mammalian brain in both normal and pathological states is ever increasing as research labs worldwide probe the various aspects of brain function. Until recently, however, comprehensive cataloging of gene expression across the central nervous system has been lacking. The Allen Institute for Brain Science, as part of its mission to propel neuroscience research, has completed several large gene-mapping projects in mouse, nonhuman primate, and human brain, producing informative online public resources and tools. Here we present the Allen Mouse Brain Atlas, covering ~20,000 genes throughout the adult mouse brain; the Allen Developing Mouse Brain Atlas, detailing expression of approximately 2,000 important developmental genes across seven embryonic and postnatal stages of brain growth; and the Allen Spinal Cord Atlas, revealing expression for ~20,000 genes in the adult and neonatal mouse spinal cords. Integrated data-mining tools, including reference atlases, informatics analyses, and 3-D viewers, are described. For these massive-scale projects, high-throughput industrial techniques were developed to standardize and reliably repeat experimental goals. To verify consistency and accuracy, a detailed analysis of the 1,000 most viewed genes for the adult mouse brain (according to website page views) was performed by comparing our data with peer-reviewed literature and other databases. We show that our data are highly consistent with independent sources and provide a comprehensive compendium of information and tools used by thousands of researchers each month. All data and tools are freely available via the Allen Brain Atlas portal (www.brain-map.org). PMID:22832508

  14. Clonal development and organization of the adult Drosophila central brain

    PubMed Central

    Yu, Hung-Hsiang; Awasaki, Takeshi; Schroeder, Mark David; Long, Fuhui; Yang, Jacob S.; He, Yisheng; Ding, Peng; Kao, Jui-Chun; Wu, Gloria Yueh-Yi; Peng, Hanchuan; Myers, Gene; Lee, Tzumin

    2013-01-01

    Summary Background The insect brain can be divided into neuropils that are formed by neurites of both local and remote origin. The complexity of the interconnections obscures how these neuropils are established and interconnected through development. The Drosophila central brain develops from a fixed number of neuroblasts (NBs) that deposit neurons in regional clusters. Results By determining individual NB clones and pursuing their projections into specific neuropils we unravel the regional development of the brain neural network. Exhaustive clonal analysis revealed 95 stereotyped neuronal lineages with characteristic cell body locations and neurite trajectories. Most clones show complex projection patterns, but despite the complexity, neighboring clones often co-innervate the same local neuropil(s) and further target a restricted set of distant neuropils. Conclusions These observations argue for regional clonal development of both neuropils and neuropil connectivity throughout the Drosophila central brain. PMID:23541733

  15. Does acute caffeine ingestion alter brain metabolism in young adults?

    PubMed

    Xu, Feng; Liu, Peiying; Pekar, James J; Lu, Hanzhang

    2015-04-15

    Caffeine, as the most commonly used stimulant drug, improves vigilance and, in some cases, cognition. However, the exact effect of caffeine on brain activity has not been fully elucidated. Because caffeine has a pronounced vascular effect which is independent of any neural effects, many hemodynamics-based methods such as fMRI cannot be readily applied without a proper calibration. The scope of the present work is two-fold. In Study 1, we used a recently developed MRI technique to examine the time-dependent changes in whole-brain cerebral metabolic rate of oxygen (CMRO2) following the ingestion of 200mg caffeine. It was found that, despite a pronounced decrease in CBF (p<0.001), global CMRO2 did not change significantly. Instead, the oxygen extraction fraction (OEF) was significantly elevated (p=0.002) to fully compensate for the reduced blood supply. Using the whole-brain finding as a reference, we aim to investigate whether there are any regional differences in the brain's response to caffeine. Therefore, in Study 2, we examined regional heterogeneities in CBF changes following the same amount of caffeine ingestion. We found that posterior brain regions such as posterior cingulate cortex and superior temporal regions manifested a slower CBF reduction, whereas anterior brain regions including dorsolateral prefrontal cortex and medial frontal cortex showed a faster rate of decline. These findings have a few possible explanations. One is that caffeine may result in a region-dependent increase or decrease in brain activity, resulting in an unaltered average brain metabolic rate. The other is that caffeine's effect on vasculature may be region-specific. Plausibility of these explanations is discussed in the context of spatial distribution of the adenosine receptors.

  16. Does acute caffeine ingestion alter brain metabolism in young adults?

    PubMed

    Xu, Feng; Liu, Peiying; Pekar, James J; Lu, Hanzhang

    2015-04-15

    Caffeine, as the most commonly used stimulant drug, improves vigilance and, in some cases, cognition. However, the exact effect of caffeine on brain activity has not been fully elucidated. Because caffeine has a pronounced vascular effect which is independent of any neural effects, many hemodynamics-based methods such as fMRI cannot be readily applied without a proper calibration. The scope of the present work is two-fold. In Study 1, we used a recently developed MRI technique to examine the time-dependent changes in whole-brain cerebral metabolic rate of oxygen (CMRO2) following the ingestion of 200mg caffeine. It was found that, despite a pronounced decrease in CBF (p<0.001), global CMRO2 did not change significantly. Instead, the oxygen extraction fraction (OEF) was significantly elevated (p=0.002) to fully compensate for the reduced blood supply. Using the whole-brain finding as a reference, we aim to investigate whether there are any regional differences in the brain's response to caffeine. Therefore, in Study 2, we examined regional heterogeneities in CBF changes following the same amount of caffeine ingestion. We found that posterior brain regions such as posterior cingulate cortex and superior temporal regions manifested a slower CBF reduction, whereas anterior brain regions including dorsolateral prefrontal cortex and medial frontal cortex showed a faster rate of decline. These findings have a few possible explanations. One is that caffeine may result in a region-dependent increase or decrease in brain activity, resulting in an unaltered average brain metabolic rate. The other is that caffeine's effect on vasculature may be region-specific. Plausibility of these explanations is discussed in the context of spatial distribution of the adenosine receptors. PMID:25644657

  17. Experience induces structural and biochemical changes in the adult primate brain.

    PubMed

    Kozorovitskiy, Yevgenia; Gross, Charles G; Kopil, Catherine; Battaglia, Lisa; McBreen, Meghan; Stranahan, Alexis M; Gould, Elizabeth

    2005-11-29

    Primates exhibit complex social and cognitive behavior in the wild. In the laboratory, however, the expression of their behavior is usually limited. A large body of literature shows that living in an enriched environment alters dendrites and synapses in the brains of adult rodents. To date, no studies have investigated the influence of living in a complex environment on brain structure in adult primates. We assessed dendritic architecture, dendritic spines, and synaptic proteins in adult marmosets housed in either a standard laboratory cage or in one of two differentially complex habitats. A month-long stay in either complex environment enhanced the length and complexity of the dendritic tree and increased dendritic spine density and synaptic protein levels in the hippocampus and prefrontal cortex. No differences were detected between the brains of marmosets living in the two differentially complex environments. Our results show that the structure of the adult primate brain remains highly sensitive even to modest levels of experiential complexity. For adult primates, living in standard laboratory housing may induce reversible dendritic spine and synapse decreases in brain regions important for cognition.

  18. Acute brain slice methods for adult and aging animals: application of targeted patch clampanalysis and optogenetics

    PubMed Central

    Daigle, Tanya L.; Chen, Qian; Feng, Guoping

    2014-01-01

    Summary The development of the living acute brain slice preparation for analyzing synaptic function roughly a half century ago was a pivotal achievement that greatly influenced the landscape of modern neuroscience. Indeed, many neuroscientists regard brain slices as the gold-standard model system for detailed cellular, molecular, and circuitry level analysis and perturbation of neuronal function. A critical limitation of this model system is the difficulty in preparing slices from adult and aging animals, and over the past several decades few substantial methodological improvements have emerged to facilitate patch clamp analysis in the mature adult stage. In this chapter we describe a robust and practical protocol for preparing brain slices from mature adult mice that are suitable for patch clamp analysis. This method reduces swelling and damage in superficial layers of the slices and improves the success rate for targeted patch clamp recordings, including recordings from fluorescently labeled populations in slices derived from transgenic mice. This adult brain slice method is suitable for diverse experimental applications, including both monitoring and manipulating neuronal activity with genetically encoded calcium indicators and optogenetic actuators, respectively. We describe the application of this adult brain slice platform and associated methods for screening kinetic properties of Channelrhodopsin (ChR) variants expressed in genetically-defined neuronal subtypes. PMID:25023312

  19. ALFY-Controlled DVL3 Autophagy Regulates Wnt Signaling, Determining Human Brain Size.

    PubMed

    Kadir, Rotem; Harel, Tamar; Markus, Barak; Perez, Yonatan; Bakhrat, Anna; Cohen, Idan; Volodarsky, Michael; Feintsein-Linial, Miora; Chervinski, Elana; Zlotogora, Joel; Sivan, Sara; Birnbaum, Ramon Y; Abdu, Uri; Shalev, Stavit; Birk, Ohad S

    2016-03-01

    Primary microcephaly is a congenital neurodevelopmental disorder of reduced head circumference and brain volume, with fewer neurons in the cortex of the developing brain due to premature transition between symmetrical and asymmetrical cellular division of the neuronal stem cell layer during neurogenesis. We now show through linkage analysis and whole exome sequencing, that a dominant mutation in ALFY, encoding an autophagy scaffold protein, causes human primary microcephaly. We demonstrate the dominant effect of the mutation in drosophila: transgenic flies harboring the human mutant allele display small brain volume, recapitulating the disease phenotype. Moreover, eye-specific expression of human mutant ALFY causes rough eye phenotype. In molecular terms, we demonstrate that normally ALFY attenuates the canonical Wnt signaling pathway via autophagy-dependent removal specifically of aggregates of DVL3 and not of Dvl1 or Dvl2. Thus, autophagic attenuation of Wnt signaling through removal of Dvl3 aggregates by ALFY acts in determining human brain size.

  20. ALFY-Controlled DVL3 Autophagy Regulates Wnt Signaling, Determining Human Brain Size

    PubMed Central

    Kadir, Rotem; Harel, Tamar; Markus, Barak; Perez, Yonatan; Bakhrat, Anna; Cohen, Idan; Volodarsky, Michael; Feintsein-Linial, Miora; Chervinski, Elana; Zlotogora, Joel; Sivan, Sara; Birnbaum, Ramon Y.; Abdu, Uri; Shalev, Stavit; Birk, Ohad S.

    2016-01-01

    Primary microcephaly is a congenital neurodevelopmental disorder of reduced head circumference and brain volume, with fewer neurons in the cortex of the developing brain due to premature transition between symmetrical and asymmetrical cellular division of the neuronal stem cell layer during neurogenesis. We now show through linkage analysis and whole exome sequencing, that a dominant mutation in ALFY, encoding an autophagy scaffold protein, causes human primary microcephaly. We demonstrate the dominant effect of the mutation in drosophila: transgenic flies harboring the human mutant allele display small brain volume, recapitulating the disease phenotype. Moreover, eye-specific expression of human mutant ALFY causes rough eye phenotype. In molecular terms, we demonstrate that normally ALFY attenuates the canonical Wnt signaling pathway via autophagy-dependent removal specifically of aggregates of DVL3 and not of Dvl1 or Dvl2. Thus, autophagic attenuation of Wnt signaling through removal of Dvl3 aggregates by ALFY acts in determining human brain size. PMID:27008544

  1. Cerebral complexity preceded enlarged brain size and reduced olfactory bulbs in Old World monkeys

    PubMed Central

    Gonzales, Lauren A.; Benefit, Brenda R.; McCrossin, Monte L.; Spoor, Fred

    2015-01-01

    Analysis of the only complete early cercopithecoid (Old World monkey) endocast currently known, that of 15-million-year (Myr)-old Victoriapithecus, reveals an unexpectedly small endocranial volume (ECV) relative to body size and a large olfactory bulb volume relative to ECV, similar to extant lemurs and Oligocene anthropoids. However, the Victoriapithecus brain has principal and arcuate sulci of the frontal lobe not seen in the stem catarrhine Aegyptopithecus, as well as a distinctive cercopithecoid pattern of gyrification, indicating that cerebral complexity preceded encephalization in cercopithecoids. Since larger ECVs, expanded frontal lobes, and reduced olfactory bulbs are already present in the 17- to 18-Myr-old ape Proconsul these features evolved independently in hominoids (apes) and cercopithecoids and much earlier in the former. Moreover, the order of encephalization and brain reorganization was apparently different in hominoids and cercopithecoids, showing that brain size and cerebral organization evolve independently. PMID:26138795

  2. Brief Report: Abnormal Association between the Thalamus and Brain Size in Asperger's Disorder

    ERIC Educational Resources Information Center

    Hardan, Antonio Y.; Girgis, Ragy R.; Adams, Jason; Gilbert, Andrew R.; Melhem, Nadine M.; Keshavan, Matcheri S.; Minshew, Nancy J.

    2008-01-01

    The objective of this study was to examine the relationship between thalamic volume and brain size in individuals with Asperger's disorder (ASP). Volumetric measurements of the thalamus were performed on MRI scans obtained from 12 individuals with ASP (age range: 10-35 years) and 12 healthy controls (age range: 9-33 years). A positive correlation…

  3. Brain Dynamics of Word Familiarization in 20-Month-Olds: Effects of Productive Vocabulary Size

    ERIC Educational Resources Information Center

    Torkildsen, Janne von Koss; Hansen, Hanna Friis; Svangstu, Janne Mari; Smith, Lars; Simonsen, Hanne Gram; Moen, Inger; Lindgren, Magnus

    2009-01-01

    The present study investigated the brain mechanisms involved during young children's receptive familiarization with new words, and whether the dynamics of these mechanisms are related to the child's productive vocabulary size. To this end, we recorded event-related potentials (ERPs) from 20-month-old children in a pseudoword repetition task.…

  4. Event-related brain potentials - Comparison between children and adults

    NASA Technical Reports Server (NTRS)

    Courchesne, E.

    1977-01-01

    The reported investigation shows that nontarget stimuli which are infrequently presented and deviate from the background elicit Nc and Pc waves in children. The same stimuli elicit P3 waves in adults. The scalp distribution of P3 waves in adults appears to vary with the ease of stimulus recognition or the degree of stimulus novelty. However, the Nc and Pc distributions in children do not seem to vary with these factors. The differences between children and adults in event-related potentials suggest corresponding differences in the mode of processing employed by each when rare, deviant stimuli are encountered

  5. Does acute caffeine ingestion alter brain metabolism in young adults?

    PubMed Central

    Xu, Feng; Liu, Peiying; Pekar, James J.; Lu, Hanzhang

    2015-01-01

    Caffeine, as the most commonly used stimulant drug, improves vigilance and, in some cases, cognition. However, the exact effect of caffeine on brain activity has not been fully elucidated. Because caffeine has a pronounced vascular effect which is independent of any neural effects, many hemodynamics-based methods such as fMRI cannot be readily applied without a proper calibration. The scope of the present work is two-fold. In Study 1, we used a recently developed MRI technique to examine the time-dependent changes in whole-brain cerebral metabolic rate of oxygen (CMRO2) following the ingestion of 200mg caffeine. It was found that, despite a pronounced decrease in CBF (p<0.001), global CMRO2 did not change significantly. Instead, the oxygen extraction fraction (OEF) was significantly elevated (p=0.002) to fully compensate for the reduced blood supply. Using the whole-brain finding as a reference, we aim to investigate whether there are any regional differences in the brain’s response to caffeine. Therefore, in Study 2, we examined regional heterogeneities in CBF changes following the same amount of caffeine ingestion. We found that posterior brain regions such as posterior cingulate cortex and superior temporal regions manifested a slower CBF reduction, whereas anterior brain regions including dorsolateral prefrontal cortex and medial frontal cortex showed a faster rate of decline. These findings have a few possible explanations. One is that caffeine may result in a region-dependent increase or decrease in brain activity, resulting in an unaltered average brain metabolic rate. The other is that caffeine’s effect on vasculature may be region-specific. Plausibility of these explanations is discussed in the context of spatial distribution of the adenosine receptors. PMID:25644657

  6. A revised dosimetric model of the adult head and brain

    SciTech Connect

    Bouchet, L.G.; Bolch, W.E.; Weber, D.A.; Atkins, H.L.; Poston, J.W. ||

    1996-07-01

    During the last decade, several new radiopharmaceuticals have been introduced for brain imaging. The marked differences of these tracers in tissue specificicity within the brain and their increasing use for diagnostic studies support the need for a more antihropomorphic model of the human brain and head. Brain and head models developed in the past have comprised only simplistic representations of this anatomic region. A new brain model has been developed which includes eight subregions: the caudate nucleus, the cerebellium, the cerebral cortex, the lateral ventricles, the lentiform nucleus, the thalamus, the third ventricle and the white matter. This brain model has been included within a slightly modified version of the head model developed by Poston et al. in 1984. The head model, which includes both the thyroid and eyes, was modified in this work to include the cerebrospinal fluid within the cranial and spinal regions. Absorbed fractions of energy for photon and electron sources located in thirteen source regions within the new head model were calculated using the EGS4 Monte Carlo radiation transport code for radiations in the energy range 10 keV to 4 MeV. S-values were calculated for five radionuclides used in brain imaging ({sup 11}C, {sup 15}O, {sup 18}F, {sup 99m}Tc and {sup 123}I) and for three radionuclides showing selective uptake in the thyroid ({sup 99m}Tc, {sup 123}I, and {sup 131}I). S-values were calculated using 100 discrete energy points in the beta-emission spectrum of the different radionuclides. 17 refs., 14 figs., 3 tabs.

  7. aBEAT: a toolbox for consistent analysis of longitudinal adult brain MRI.

    PubMed

    Dai, Yakang; Wang, Yaping; Wang, Li; Wu, Guorong; Shi, Feng; Shen, Dinggang

    2013-01-01

    Longitudinal brain image analysis is critical for revealing subtle but complex structural and functional changes of brain during aging or in neurodevelopmental disease. However, even with the rapid increase of clinical research and trials, a software toolbox dedicated for longitudinal image analysis is still lacking publicly. To cater for this increasing need, we have developed a dedicated 4D Adult Brain Extraction and Analysis Toolbox (aBEAT) to provide robust and accurate analysis of the longitudinal adult brain MR images. Specially, a group of image processing tools were integrated into aBEAT, including 4D brain extraction, 4D tissue segmentation, and 4D brain labeling. First, a 4D deformable-surface-based brain extraction algorithm, which can deform serial brain surfaces simultaneously under temporal smoothness constraint, was developed for consistent brain extraction. Second, a level-sets-based 4D tissue segmentation algorithm that incorporates local intensity distribution, spatial cortical-thickness constraint, and temporal cortical-thickness consistency was also included in aBEAT for consistent brain tissue segmentation. Third, a longitudinal groupwise image registration framework was further integrated into aBEAT for consistent ROI labeling by simultaneously warping a pre-labeled brain atlas to the longitudinal brain images. The performance of aBEAT has been extensively evaluated on a large number of longitudinal MR T1 images which include normal and dementia subjects, achieving very promising results. A Linux-based standalone package of aBEAT is now freely available at http://www.nitrc.org/projects/abeat.

  8. Brain size and encephalization in early to Mid-Pleistocene Homo.

    PubMed

    Rightmire, G Philip

    2004-06-01

    Important changes in the brain have occurred during the course of human evolution. Both absolute and relative size increases can be documented for species of Homo, culminating in the appearance of modern humans. One species that is particularly well-represented by fossil crania is Homo erectus. The mean capacity for 30 individuals is 973 cm(3). Within this group there is substantial variation, but brain size increases slightly in specimens from later time periods. Other Middle Pleistocene crania differ from those of Homo erectus. Characters of the facial skeleton, vault, and cranial base suggest that fossils from sites such as Arago Cave in France, the Sima de los Huesos in Spain, Bodo in Ethiopia, Broken Hill in Zambia, and perhaps Dali in China belong to the taxon Homo heidelbergensis. Ten of these mid-Quaternary hominins have brains averaging 1,206 cm(3) in volume, and many fall beyond the limits of size predicted for Homo erectus of equivalent age. When orbit height is used to construct an index of relative brain size, it is apparent that the (significant) increase in volume documented for the Middle Pleistocene individuals is not simply a consequence of larger body mass. Encephalization quotient values confirm this finding. These changes in absolute and relative brain size can be taken as further corroborative evidence for a speciation event, in which Homo erectus produced a daughter lineage. It is probable that Homo heidelbergensis originated in Africa or western Eurasia and then ranged widely across the Old World. Archaeological traces indicate that these populations differed in their technology and behavior from earlier hominins.

  9. Laterality of mental imagery generation and operation: tests with brain-damaged patients and normal adults.

    PubMed

    Hatta, T; Koike, M; Langman, P

    1994-08-01

    The relationships between hemispheric function and components of the imagery process were examined in patients with unilateral right and left brain damage and in intact adult subjects. In the image generation condition, subjects were required to mentally generate Katakana letters corresponding to Hiragana letters displayed on a CRT. The results for the intact adults suggested a left hemisphere superiority, but the unilaterally brain-damaged subjects showed no hemispheric difference in this task. In the imagery operation task (transformation or lateral translation), subjects were asked to find a genuine Kanji among distractors (pseudo-Kanji) that were constructed from two Kanji radicals (themselves real Kanji) that were either displayed in reverse order or shifted apart. The results for both intact adults and patients with unilateral brain damage suggest the superiority of the right hemisphere. PMID:7525640

  10. The antidepressant tranylcypromine alters cellular proliferation and migration in the adult goldfish brain.

    PubMed

    Romanczyk, Tara B; Jacobowitz, David M; Pollard, Harvey B; Wu, Xingjia; Anders, Juanita J

    2014-10-01

    The goldfish (Carassius auratus) is a widely studied vertebrate model organism for studying cell proliferation in the adult brain, and provide the experimental advantage of growing their body and brain throughout their ∼30-year life time. Cell proliferation occurs in the teleost brain in widespread proliferation zones. Increased cell proliferation in the brain has been linked to the actions of certain antidepressants, including tranylcypromine (TCP), which is used in the treatment of depression. We hypothesized that proliferation zones in the adult goldfish brain can be used to determine the antidepressant effects on cellular proliferation. Here, we report that bromodeoxyuridine (BrdU) labeling over a 24-hr period can be used to rapidly identify the proliferation zones throughout the goldfish brain, including the telencephalon, diencephalon, optic tectal lobes, cerebellum, and facial and vagal lobes. In the first 24 hr of BrdU administration, TCP caused an approximate and significant doubling of labeled cells in the combined brain regions examined, as detected by BrdU immunohistochemistry. TCP caused the greatest increase in cell proliferation in the cerebellum. The normal migratory paths of the proliferating cells within the cerebellum were not affected by TCP treatment. These results indicate that the goldfish provide significant advantages as a vertebrate model for rapidly investigating the effects of antidepressant drugs on cellular proliferation and migration in the normal and injured brain.

  11. Dietary resistant starch improves selected brain and behavioral functions in adult and aged rodents

    PubMed Central

    Zhou, June; Keenan, Michael J.; Fernandez-Kim, Sun Ok; Pistell, Paul J.; Ingram, Donald K.; Li, Bing; Raggio, Anne M.; Shen, Li; Zhang, Hanjie; McCutcheon, Kathleen L; Tulley, Richard T.; Blackman, Marc R.; Keller, Jeffrey N.; Martin, Roy J.

    2013-01-01

    Resistant starch (RS) is a dietary fiber that exerts multiple beneficial effects. The current study explored the effects of dietary RS on selected brain and behavioral functions in adult and aged rodents. Because glucokinase (GK) expression in hypothalamic arcuate nucleus and area postrema of the brainstem is important for brain glucose sensing, GK mRNA was measured by brain nuclei microdissection and PCR. Adult RS-fed rats had a higher GK mRNA than controls in both brain nuclei, an indicator of improved brain glucose sensing. Next, we tested whether dietary RS improve selected behaviors in aged mice. RS-fed aged mice exhibited (1) an increased eating responses to fasting, a behavioral indicator of improvement in aged brain glucose sensing; (2) a longer latency to fall from an accelerating rotarod, a behavioral indicator of improved motor coordination; and (3) a higher serum active GLP-1. Third, GLP-1 receptor null (GLP-1RKO) mice were used to test the role of GLP-1 in brain glucose sensing, and they exhibited impaired eating responses to fasting. We conclude that in rodents (1) dietary RS improves two important indicators of brain function: glucose sensing and motor coordination, and that (2) GLP-1 is important in the optimal feeding response to a fast. PMID:23818307

  12. Dietary resistant starch improves selected brain and behavioral functions in adult and aged rodents.

    PubMed

    Zhou, June; Keenan, Michael J; Fernandez-Kim, Sun Ok; Pistell, Paul J; Ingram, Donald K; Li, Bing; Raggio, Anne M; Shen, Li; Zhang, Hanjie; McCutcheon, Kathleen L; Tulley, Richard T; Blackman, Marc R; Keller, Jeffrey N; Martin, Roy J

    2013-11-01

    Resistant starch (RS) is a dietary fiber that exerts multiple beneficial effects. The current study explored the effects of dietary RS on selected brain and behavioral functions in adult and aged rodents. Because glucokinase (GK) expression in hypothalamic arcuate nucleus and area postrema of the brainstem is important for brain glucose sensing, GK mRNA was measured by brain nuclei microdissection and PCR. Adult RS-fed rats had a higher GK mRNA than controls in both brain nuclei, an indicator of improved brain glucose sensing. Next, we tested whether dietary RS improve selected behaviors in aged mice. RS-fed aged mice exhibited (i) an increased eating responses to fasting, a behavioral indicator of improvement in aged brain glucose sensing; (ii) a longer latency to fall from an accelerating rotarod, a behavioral indicator of improved motor coordination; and (iii) a higher serum active glucagon-like peptide-1 (GLP-1). Then, GLP-1 receptor null (GLP-1RKO) mice were used to test the role of GLP-1 in brain glucose sensing, and they exhibited impaired eating responses to fasting. We conclude that in rodents (i) dietary RS improves two important indicators of brain function: glucose sensing and motor coordination, and (ii) GLP-1 is important in the optimal feeding response to a fast.

  13. Is docosahexaenoic acid synthesis from α-linolenic acid sufficient to supply the adult brain?

    PubMed

    Domenichiello, Anthony F; Kitson, Alex P; Bazinet, Richard P

    2015-07-01

    Docosahexaenoic acid (DHA) is important for brain function, and can be obtained directly from the diet or synthesized in the body from α-linolenic acid (ALA). Debate exists as to whether DHA synthesized from ALA can provide sufficient DHA for the adult brain, as measures of DHA synthesis from ingested ALA are typically <1% of the oral ALA dose. However, the primary fate of orally administered ALA is β-oxidation and long-term storage in adipose tissue, suggesting that DHA synthesis measures involving oral ALA tracer ingestion may underestimate total DHA synthesis. There is also evidence that DHA synthesized from ALA can meet brain DHA requirements, as animals fed ALA-only diets have brain DHA concentrations similar to DHA-fed animals, and the brain DHA requirement is estimated to be only 2.4-3.8 mg/day in humans. This review summarizes evidence that DHA synthesis from ALA can provide sufficient DHA for the adult brain by examining work in humans and animals involving estimates of DHA synthesis and brain DHA requirements. Also, an update on methods to measure DHA synthesis in humans is presented highlighting a novel approach involving steady-state infusion of stable isotope-labeled ALA that bypasses several limitations of oral tracer ingestion. It is shown that this method produces estimates of DHA synthesis that are at least 3-fold higher than brain uptake rates in rats.

  14. Ephrin/Eph receptor expression in brain of adult nonhuman primates: implications for neuroadaptation.

    PubMed

    Xiao, Danqing; Miller, Gregory M; Jassen, Amy; Westmoreland, Susan V; Pauley, Douglas; Madras, Bertha K

    2006-01-01

    In developing brain, Eph receptors and their ephrin ligands (Ephs/ephrins) are implicated in facilitating topographic guidance of a number of pathways, including the nigrostriatal and mesolimbic dopamine (DA) pathways. In adult rodent brain, these molecules are implicated in neuronal plasticity associated with learning and memory. Cocaine significantly alters the expression of select members of this family of axonal guidance molecules, implicating Ephs, ephrins in drug-induced neuroadaptation. The potential contribution of Ephs, ephrins to cocaine-induced reorganization of striatal circuitry brain in primates [Saka, E., Goodrich, C., Harlan, P., Madras, B.K., Graybiel, A.M., 2004. Repetitive behaviors in monkeys are linked to specific striatal activation patterns. J. Neurosci. 24, 7557-7565] is unknown because there are no documented reports of Eph/ephrin expression or function in adult primate brain. We now report that brains of adult old and new world monkeys express mRNA encoding EphA4 receptor and ephrin-B2 ligand, implicated in topographic guidance of dopamine and striatal neurons during development. Their encoded proteins distributed highly selectively in regions of adult monkey brain. EphA4 mRNA levels were prominent in the DA-rich caudate/putamen, nucleus accumbens and globus pallidus, as well as the medial and orbitofrontal cortices, hippocampus, amygdala, thalamus and cerebellum. Immunocytochemical localization of EphA4 protein revealed discrete expression in caudate/putamen, globus pallidus, substantia nigra, cerebellar Purkinje cells, pyramidal cells of frontal cortices (layers II, III and V) and the subgranular zone of the hippocampus. Evidence for EphA4 expression in dopamine neurons emerged from colocalization with tyrosine-hydroxylase-positive terminals in striatum and substantia nigra and ventral tegmental area cell bodies. The association of axonal guidance molecules with drug-induced reorganization of adult primate brain circuitry warrants

  15. Effects of problem size and arithmetic operation on brain activation during calculation in children with varying levels of arithmetical fluency.

    PubMed

    De Smedt, Bert; Holloway, Ian D; Ansari, Daniel

    2011-08-01

    Most studies on mathematics learning in the field of educational neuroscience have focused on the neural correlates of very elementary numerical processing skills in children. Little is known about more complex mathematical skills that are formally taught in school, such as arithmetic. Using functional magnetic resonance imaging, the present study investigated how brain activation during single-digit addition and subtraction is modulated by problem size and arithmetic operation in 28 children aged 10-12 years with different levels of arithmetical fluency. Commensurate with adult data, large problems and subtractions activated a fronto-parietal network, including the intraparietal sulci, the latter of which indicates the influence of quantity-based processes during procedural strategy execution. Different from adults, the present findings revealed that particularly the left hippocampus was active during the solution of those problems that are expected to be solved by means of fact retrieval (i.e. small problems and addition), suggesting a specific role of the hippocampus in the early stages of learning arithmetic facts. Children with low levels of arithmetical fluency showed higher activation in the right intraparietal sulcus during the solution of problems with a relatively small problem size, indicating that they continued to rely to a greater extent on quantity-based strategies on those problems that the children with relatively higher arithmetical fluency already retrieved from memory. This might represent a neural correlate of fact retrieval impairments in children with mathematical difficulties. PMID:21182966

  16. Can adult and juvenile European rabbits be differentiated by their pellet sizes?

    NASA Astrophysics Data System (ADS)

    Delibes-Mateos, Miguel; Rouco, Carlos; Villafuerte, Rafael

    2009-03-01

    Recently, a new method for differentiating juvenile and adult rabbits based on faecal pellet size was published. According to this method, pellets >6 mm diameter are inferred to be deposited by adults, while those <6 mm are inferred to be from juveniles or kittens. In this study, we designed a simple experiment to test the accuracy of this methodology. Twelve adult rabbits were housed in individual outdoor cages and their pellets were removed every day for 10 consecutive days. Pellets were separated using a sieve according to their size and counted. Results showed that adult rabbits produce pellets >6 mm diameter in the same proportion as those <6 mm. We also observed a strong influence of the individual rabbit on pellet size; some rabbits produce a high proportion of pellets >6 mm, whereas others deposit mostly pellets <6 mm in size. Our findings demonstrate that pellet size is unsuitable for aging wild rabbits. Field biologists should therefore be cautious when employing the pellet size method of age determination in other wild animals in the absence of validating studies.

  17. Delineating multiple functions of VEGF-A in the adult brain.

    PubMed

    Licht, Tamar; Keshet, Eli

    2013-05-01

    Vascular endothelial growth factor-A (abbreviated throughout this review as VEGF) is mostly known for its angiogenic activity, for its activity as a vascular permeability factor, and for its vascular survival activity [1]. There is a growing body of evidence, however, that VEGF fulfills additional less 'traditional' functions in multiple organs, both during development, as well as homeostatic functions in fully developed organs. This review focuses on the multiple roles of VEGF in the adult brain and is less concerned with the roles played by VEGF during brain development, functions described elsewhere in this review series. Most functions of VEGF that are essential for proper brain development are, in fact, dispensable in the adult brain as was clearly demonstrated using a conditional brain-specific VEGF loss-of-function (LOF) approach. Thus, in contrast to VEGF LOF in the developing brain, a process which is detrimental for the growth and survival of blood vessels and leads to massive neuronal apoptosis [2-4], continued signaling by VEGF in the mature brain is no longer required for maintaining already established cerebral vasculature and its inhibition does not cause appreciable vessel regression, hypoxia or apoptosis [4-7]. Yet, VEGF continues to be expressed in the adult brain in a constitutive manner. Moreover, VEGF is expressed in the adult brain in a region-specific manner and in distinctive spatial patterns incompatible with an angiogenic role (see below), strongly suggesting angiogenesis-independent and possibly also perfusion-independent functions. Here we review current knowledge on some of these 'non-traditional', often unexpected homeostatic VEGF functions, including those unrelated to its effects on the brain vasculature. These effects could be mediated directly (on non-vascular cells expressing cognate VEGF receptors) or indirectly (via the endothelium). Experimental approaches aimed at distinguishing between these possibilities for each particular

  18. Postoperative Stereotactic Radiosurgery Without Whole-Brain Radiation Therapy for Brain Metastases: Potential Role of Preoperative Tumor Size

    SciTech Connect

    Hartford, Alan C.; Paravati, Anthony J.; Spire, William J.; Li, Zhongze; Jarvis, Lesley A.; Fadul, Camilo E.; Erkmen, Kadir; Friedman, Jonathan; Gladstone, David J.; Hug, Eugen B.; Roberts, David W.; Simmons, Nathan E.

    2013-03-01

    Purpose: Radiation therapy following resection of a brain metastasis increases the probability of disease control at the surgical site. We analyzed our experience with postoperative stereotactic radiosurgery (SRS) as an alternative to whole-brain radiotherapy (WBRT), with an emphasis on identifying factors that might predict intracranial disease control and overall survival (OS). Methods and Materials: We retrospectively reviewed all patients through December 2008, who, after surgical resection, underwent SRS to the tumor bed, deferring WBRT. Multiple factors were analyzed for time to intracranial recurrence (ICR), whether local recurrence (LR) at the surgical bed or “distant” recurrence (DR) in the brain, for time to WBRT, and for OS. Results: A total of 49 lesions in 47 patients were treated with postoperative SRS. With median follow-up of 9.3 months (range, 1.1-61.4 months), local control rates at the resection cavity were 85.5% at 1 year and 66.9% at 2 years. OS rates at 1 and 2 years were 52.5% and 31.7%, respectively. On univariate analysis (preoperative) tumors larger than 3.0 cm exhibited a significantly shorter time to LR. At a cutoff of 2.0 cm, larger tumors resulted in significantly shorter times not only for LR but also for DR, ICR, and salvage WBRT. While multivariate Cox regressions showed preoperative size to be significant for times to DR, ICR, and WBRT, in similar multivariate analysis for OS, only the graded prognostic assessment proved to be significant. However, the number of intracranial metastases at presentation was not significantly associated with OS nor with other outcome variables. Conclusions: Larger tumor size was associated with shorter time to recurrence and with shorter time to salvage WBRT; however, larger tumors were not associated with decrements in OS, suggesting successful salvage. SRS to the tumor bed without WBRT is an effective treatment for resected brain metastases, achieving local control particularly for tumors up to

  19. Cranial irradiation induces bone marrow-derived microglia in adult mouse brain tissue.

    PubMed

    Okonogi, Noriyuki; Nakamura, Kazuhiro; Suzuki, Yoshiyuki; Suto, Nana; Suzue, Kazutomo; Kaminuma, Takuya; Nakano, Takashi; Hirai, Hirokazu

    2014-07-01

    Postnatal hematopoietic progenitor cells do not contribute to microglial homeostasis in adult mice under normal conditions. However, previous studies using whole-body irradiation and bone marrow (BM) transplantation models have shown that adult BM cells migrate into the brain tissue and differentiate into microglia (BM-derived microglia; BMDM). Here, we investigated whether cranial irradiation alone was sufficient to induce the generation of BMDM in the adult mouse brain. Transgenic mice that express green fluorescent protein (GFP) under the control of a murine stem cell virus (MSCV) promoter (MSCV-GFP mice) were used. MSCV-GFP mice express GFP in BM cells but not in the resident microglia in the brain. Therefore, these mice allowed us to detect BM-derived cells in the brain without BM reconstitution. MSCV-GFP mice, aged 8-12 weeks, received 13.0 Gy irradiation only to the cranium, and BM-derived cells in the brain were quantified at 3 and 8 weeks after irradiation. No BM-derived cells were detected in control non-irradiated MSCV-GFP mouse brains, but numerous GFP-labeled BM-derived cells were present in the brain stem, basal ganglia and cerebral cortex of the irradiated MSCV-GFP mice. These BM-derived cells were positive for Iba1, a marker for microglia, indicating that GFP-positive BM-derived cells were microglial in nature. The population of BMDM was significantly greater at 8 weeks post-irradiation than at 3 weeks post-irradiation in all brain regions examined. Our results clearly show that cranial irradiation alone is sufficient to induce the generation of BMDM in the adult mouse.

  20. Brain size regulations by cbp haploinsufficiency evaluated by in-vivo MRI based volumetry

    NASA Astrophysics Data System (ADS)

    Ateca-Cabarga, Juan C.; Cosa, Alejandro; Pallarés, Vicente; López-Atalaya, José P.; Barco, Ángel; Canals, Santiago; Moratal, David

    2015-11-01

    The Rubinstein-Taybi Syndrome (RSTS) is a congenital disease that affects brain development causing severe cognitive deficits. In most cases the disease is associated with dominant mutations in the gene encoding the CREB binding protein (CBP). In this work, we present the first quantitative analysis of brain abnormalities in a mouse model of RSTS using magnetic resonance imaging (MRI) and two novel self-developed automated algorithms for image volumetric analysis. Our results quantitatively confirm key syndromic features observed in RSTS patients, such as reductions in brain size (-16.31%, p < 0.05), white matter volume (-16.00%, p < 0.05), and corpus callosum (-12.40%, p < 0.05). Furthermore, they provide new insight into the developmental origin of the disease. By comparing brain tissues in a region by region basis between cbp+/- and cbp+/+ littermates, we found that cbp haploinsufficiency is specifically associated with significant reductions in prosencephalic tissue, such us in the olfactory bulb and neocortex, whereas regions evolved from the embryonic rhombencephalon were spared. Despite the large volume reductions, the proportion between gray-, white-matter and cerebrospinal fluid were conserved, suggesting a role of CBP in brain size regulation. The commonalities with holoprosencephaly and arhinencephaly conditions suggest the inclusion of RSTS in the family of neuronal migration disorders.

  1. Brain size regulations by cbp haploinsufficiency evaluated by in-vivo MRI based volumetry

    PubMed Central

    Ateca-Cabarga, Juan C.; Cosa, Alejandro; Pallarés, Vicente; López-Atalaya, José P.; Barco, Ángel; Canals, Santiago; Moratal, David

    2015-01-01

    The Rubinstein-Taybi Syndrome (RSTS) is a congenital disease that affects brain development causing severe cognitive deficits. In most cases the disease is associated with dominant mutations in the gene encoding the CREB binding protein (CBP). In this work, we present the first quantitative analysis of brain abnormalities in a mouse model of RSTS using magnetic resonance imaging (MRI) and two novel self-developed automated algorithms for image volumetric analysis. Our results quantitatively confirm key syndromic features observed in RSTS patients, such as reductions in brain size (−16.31%, p < 0.05), white matter volume (−16.00%, p < 0.05), and corpus callosum (−12.40%, p < 0.05). Furthermore, they provide new insight into the developmental origin of the disease. By comparing brain tissues in a region by region basis between cbp+/− and cbp+/+ littermates, we found that cbp haploinsufficiency is specifically associated with significant reductions in prosencephalic tissue, such us in the olfactory bulb and neocortex, whereas regions evolved from the embryonic rhombencephalon were spared. Despite the large volume reductions, the proportion between gray-, white-matter and cerebrospinal fluid were conserved, suggesting a role of CBP in brain size regulation. The commonalities with holoprosencephaly and arhinencephaly conditions suggest the inclusion of RSTS in the family of neuronal migration disorders. PMID:26543002

  2. Radial glial cell-specific ablation in the adult Zebrafish brain.

    PubMed

    Shimizu, Yuki; Ito, Yoko; Tanaka, Hideomi; Ohshima, Toshio

    2015-07-01

    The zebrafish brain can continue to produce new neurons in widespread neurogenic brain regions throughout life. In contrast, neurogenesis in the adult mammalian brain is restricted to the subventricular zone (SVZ) and dentate gyrus (DG). In neurogenic regions in the adult brain, radial glial cells (RGCs) are considered to function as neural stem cells (NSCs). We generated a Tg(gfap:Gal4FF) transgenic zebrafish line, which enabled us to express specific genes in RGCs. To study the function of RGCs in neurogenesis in the adult zebrafish brain, we also generated a Tg(gfap: Gal4FF; UAS:nfsB-mcherry) transgenic zebrafish line, which allowed us to induce cell death exclusively within RGCs upon addition of metronidazole (Mtz) to the media. RGCs expressing nitroreductase were specifically ablated by the Mtz treatment, decreasing the number of proliferative RGCs. Using the Tg(gfap:Gal4FF; UAS:nfsB-mcherry) transgenic zebrafish line, we found that RGCs were specifically ablated in the adult zebrafish telencephalon. The Tg(gfap:Gal4FF) line could be useful to study the function of RGCs.

  3. Differential Expression of protocadherin-19, protocadherin-17 and cadherin-6 in Adult Zebrafish Brain

    PubMed Central

    Liu, Qin; Bhattarai, Sunil; Wang, Nan; Sochacka-Marlowe, Alicja

    2015-01-01

    Cell adhesion molecule cadherins play important roles in both development and maintenance of adult structures. Most studies on cadherin expression have been carried out in developing organisms, but information on cadherin distribution in adult vertebrate brains is limited. In this study, we used in situ hybridization to examine mRNA expression of three cadherins, protocadherin-19, protocadherin-17 and cadherin-6 in adult zebrafish brain. Each cadherin exhibits a distinct expression pattern in the fish brain, with protocadherin-19 and protocadherin-17 showing much wider and stronger expression than that of cadherin-6. Both protocadherin-19 and protocadherin-17 expressing cells occur throughout the brain with strong expression in the ventromedial telencephalon, periventricular regions of the thalamus and anterior hypothalamus, stratum periventriculare of the optic tectum, dorsal tegmental nucleus, granular regions of the cerebellar body and valvula, and superficial layers of the facial and vagal lobes. Numerous sensory structures (e.g. auditory, gustatory, lateral line, olfactory and visual nuclei) and motor nuclei (e.g. oculomotor, trochlear, trigeminal motor, abducens and vagal motor nuclei) contain protocadherin-19 and/or protocadherin-17 expressing cell. Expression of these two protocadherins is similar in the ventromedial telencephalon, thalamus, hypothalamus, facial and vagal lobes, but substantially different in the dorsolateral telencephalon, intermediate layers of the optic tectum, and cerebellar valvula. In contrast to the two protocadherins, cadherin-6 expression is much weaker and limited in the adult fish brain. PMID:25612302

  4. Localization of PPAR isotypes in the adult mouse and human brain

    PubMed Central

    Warden, Anna; Truitt, Jay; Merriman, Morgan; Ponomareva, Olga; Jameson, Kelly; Ferguson, Laura B.; Mayfield, R. Dayne; Harris, R. Adron

    2016-01-01

    Peroxisome proliferator-activated receptors (PPARs) are nuclear hormone receptors that act as ligand-activated transcription factors. PPAR agonists have well-documented anti-inflammatory and neuroprotective roles in the central nervous system. Recent evidence suggests that PPAR agonists are attractive therapeutic agents for treating neurodegenerative diseases as well as addiction. However, the distribution of PPAR mRNA and protein in brain regions associated with these conditions (i.e. prefrontal cortex, nucleus accumbens, amygdala, ventral tegmental area) is not well defined. Moreover, the cell type specificity of PPARs in mouse and human brain tissue has yet to be investigated. We utilized quantitative PCR and double immunofluorescence microscopy to determine that both PPAR mRNA and protein are expressed ubiquitously throughout the adult mouse brain. We found that PPARs have unique cell type specificities that are consistent between species. PPARα was the only isotype to colocalize with all cell types in both adult mouse and adult human brain tissue. Overall, we observed a strong neuronal signature, which raises the possibility that PPAR agonists may be targeting neurons rather than glia to produce neuroprotection. Our results fill critical gaps in PPAR distribution and define novel cell type specificity profiles in the adult mouse and human brain. PMID:27283430

  5. Differential expression of protocadherin-19, protocadherin-17, and cadherin-6 in adult zebrafish brain.

    PubMed

    Liu, Qin; Bhattarai, Sunil; Wang, Nan; Sochacka-Marlowe, Alicja

    2015-06-15

    Cell adhesion molecule cadherins play important roles in both development and maintenance of adult structures. Most studies on cadherin expression have been carried out in developing organisms, but information on cadherin distribution in adult vertebrate brains is limited. In this study we used in situ hybridization to examine mRNA expression of three cadherins, protocadherin-19, protocadherin-17, and cadherin-6 in adult zebrafish brain. Each cadherin exhibits a distinct expression pattern in the fish brain, with protocadherin-19 and protocadherin-17 showing much wider and stronger expression than that of cadherin-6. Both protocadherin-19 and protocadherin-17-expressing cells occur throughout the brain, with strong expression in the ventromedial telencephalon, periventricular regions of the thalamus and anterior hypothalamus, stratum periventriculare of the optic tectum, dorsal tegmental nucleus, granular regions of the cerebellar body and valvula, and superficial layers of the facial and vagal lobes. Numerous sensory structures (e.g., auditory, gustatory, lateral line, olfactory, and visual nuclei) and motor nuclei (e.g., oculomotor, trochlear, trigeminal motor, abducens, and vagal motor nuclei) contain protocadherin-19 and/or protocadherin-17-expressing cell. Expression of these two protocadherins is similar in the ventromedial telencephalon, thalamus, hypothalamus, facial, and vagal lobes, but substantially different in the dorsolateral telencephalon, intermediate layers of the optic tectum, and cerebellar valvula. In contrast to the two protocadherins, cadherin-6 expression is much weaker and limited in the adult fish brain.

  6. Bi-parental care contributes to sexually dimorphic neural cell genesis in the adult mammalian brain.

    PubMed

    Mak, Gloria K; Antle, Michael C; Dyck, Richard H; Weiss, Samuel

    2013-01-01

    Early life events can modulate brain development to produce persistent physiological and behavioural phenotypes that are transmissible across generations. However, whether neural precursor cells are altered by early life events, to produce persistent and transmissible behavioural changes, is unknown. Here, we show that bi-parental care, in early life, increases neural cell genesis in the adult rodent brain in a sexually dimorphic manner. Bi-parentally raised male mice display enhanced adult dentate gyrus neurogenesis, which improves hippocampal neurogenesis-dependent learning and memory. Female mice display enhanced adult white matter oligodendrocyte production, which increases proficiency in bilateral motor coordination and preference for social investigation. Surprisingly, single parent-raised male and female offspring, whose fathers and mothers received bi-parental care, respectively, display a similar enhancement in adult neural cell genesis and phenotypic behaviour. Therefore, neural plasticity and behavioural effects due to bi-parental care persist throughout life and are transmitted to the next generation.

  7. Metabolic acceleration and the evolution of human brain size and life history.

    PubMed

    Pontzer, Herman; Brown, Mary H; Raichlen, David A; Dunsworth, Holly; Hare, Brian; Walker, Kara; Luke, Amy; Dugas, Lara R; Durazo-Arvizu, Ramon; Schoeller, Dale; Plange-Rhule, Jacob; Bovet, Pascal; Forrester, Terrence E; Lambert, Estelle V; Thompson, Melissa Emery; Shumaker, Robert W; Ross, Stephen R

    2016-05-19

    Humans are distinguished from the other living apes in having larger brains and an unusual life history that combines high reproductive output with slow childhood growth and exceptional longevity. This suite of derived traits suggests major changes in energy expenditure and allocation in the human lineage, but direct measures of human and ape metabolism are needed to compare evolved energy strategies among hominoids. Here we used doubly labelled water measurements of total energy expenditure (TEE; kcal day(-1)) in humans, chimpanzees, bonobos, gorillas and orangutans to test the hypothesis that the human lineage has experienced an acceleration in metabolic rate, providing energy for larger brains and faster reproduction without sacrificing maintenance and longevity. In multivariate regressions including body size and physical activity, human TEE exceeded that of chimpanzees and bonobos, gorillas and orangutans by approximately 400, 635 and 820 kcal day(-1), respectively, readily accommodating the cost of humans' greater brain size and reproductive output. Much of the increase in TEE is attributable to humans' greater basal metabolic rate (kcal day(-1)), indicating increased organ metabolic activity. Humans also had the greatest body fat percentage. An increased metabolic rate, along with changes in energy allocation, was crucial in the evolution of human brain size and life history. PMID:27144364

  8. Metabolic acceleration and the evolution of human brain size and life history

    PubMed Central

    Pontzer, Herman; Brown, Mary H.; Raichlen, David A.; Dunsworth, Holly; Hare, Brian; Walker, Kara; Luke, Amy; Dugas, Lara R.; Durazo-Arvizu, Ramon; Schoeller, Dale; Plange-Rhule, Jacob; Bovet, Pascal; Forrester, Terrence E.; Lambert, Estelle V.; Thompson, Melissa Emery; Shumaker, Robert W.; Ross, Stephen R.

    2016-01-01

    Humans are distinguished from the other living apes in having larger brains and an unusual life history that combines high reproductive output with slow childhood growth and exceptional longevity1. This suite of derived traits suggests major changes in energy expenditure and allocation in the human lineage, but direct measures of human and ape metabolism are needed to compare evolved energy strategies among hominoids. Here we used doubly labelled water measurements of total energy expenditure (TEE; kcal day−1) in humans, chimpanzees, bonobos, gorillas and orangutans to test the hypothesis that the human lineage has experienced an acceleration in metabolic rate, providing energy for larger brains and faster reproduction without sacrificing maintenance and longevity. In multivariate regressions including body size and physical activity, human TEE exceeded that of chimpanzees and bonobos, gorillas and orangutans by approximately 400, 635 and 820 kcal day−1, respectively, readily accommodating the cost of humans' greater brain size and reproductive output. Much of the increase in TEE is attributable to humans' greater basal metabolic rate (kcal day−1), indicating increased organ metabolic activity. Humans also had the greatest body fat percentage. An increased metabolic rate, along with changes in energy allocation, was crucial in the evolution of human brain size and life history. PMID:27144364

  9. Metabolic acceleration and the evolution of human brain size and life history.

    PubMed

    Pontzer, Herman; Brown, Mary H; Raichlen, David A; Dunsworth, Holly; Hare, Brian; Walker, Kara; Luke, Amy; Dugas, Lara R; Durazo-Arvizu, Ramon; Schoeller, Dale; Plange-Rhule, Jacob; Bovet, Pascal; Forrester, Terrence E; Lambert, Estelle V; Thompson, Melissa Emery; Shumaker, Robert W; Ross, Stephen R

    2016-05-04

    Humans are distinguished from the other living apes in having larger brains and an unusual life history that combines high reproductive output with slow childhood growth and exceptional longevity. This suite of derived traits suggests major changes in energy expenditure and allocation in the human lineage, but direct measures of human and ape metabolism are needed to compare evolved energy strategies among hominoids. Here we used doubly labelled water measurements of total energy expenditure (TEE; kcal day(-1)) in humans, chimpanzees, bonobos, gorillas and orangutans to test the hypothesis that the human lineage has experienced an acceleration in metabolic rate, providing energy for larger brains and faster reproduction without sacrificing maintenance and longevity. In multivariate regressions including body size and physical activity, human TEE exceeded that of chimpanzees and bonobos, gorillas and orangutans by approximately 400, 635 and 820 kcal day(-1), respectively, readily accommodating the cost of humans' greater brain size and reproductive output. Much of the increase in TEE is attributable to humans' greater basal metabolic rate (kcal day(-1)), indicating increased organ metabolic activity. Humans also had the greatest body fat percentage. An increased metabolic rate, along with changes in energy allocation, was crucial in the evolution of human brain size and life history.

  10. Oligodendrogenesis in the fornix of adult mouse brain; the effect of LPS-induced inflammatory stimulation.

    PubMed

    Fukushima, Shohei; Nishikawa, Kazunori; Furube, Eriko; Muneoka, Shiori; Ono, Katsuhiko; Takebayashi, Hirohide; Miyata, Seiji

    2015-11-19

    Evidence have been accumulated that continuous oligodendrogenesis occurs in the adult mammalian brain. The fornix, projection and commissure pathway of hippocampal neurons, carries signals from the hippocampus to other parts of the brain and has critical role in memory and learning. However, basic characterization of adult oligodendrogenesis in this brain region is not well understood. In the present study, therefore, we aimed to examine the proliferation and differentiation of oligodendrocyte progenitor cells (OPCs) and the effect of acute inflammatory stimulation on oligodendrogenesis in the fornix of adult mouse. We demonstrated the proliferation of OPCs and a new generation of mature oligodendrocytes by using bromodeoxyuridine and Ki67 immunohistochemistry. Oligodendrogenesis of adult fornix was also demonstrated by using oligodendrocyte transcription factor 2 transgenic mouse. A single systemic administration of lipopolysaccharide (LPS) attenuated proliferation of OPCs in the fornix together with reduced proliferation of hippocampal neural stem/progenitor cells. Time course analysis showed that a single administration of LPS attenuated the proliferation of OPCs during 24-48 h. On the other hand, consecutive administration of LPS did not suppress proliferation of OPCs. The treatment of LPS did not affect differentiation of OPCs into mature oligodendrocytes. Treatment of a microglia inhibitor minocycline significantly attenuated basal proliferation of OPCs under normal condition. In conclusion, the present study indicates that continuous oligodendrogenesis occurs and a single administration of LPS transiently attenuates proliferation of OPCs without changing differentiation in the fornix of the adult mouse brains.

  11. DUF1220-Domain Copy Number Implicated in Human Brain-Size Pathology and Evolution

    PubMed Central

    Dumas, Laura J.; O’Bleness, Majesta S.; Davis, Jonathan M.; Dickens, C. Michael; Anderson, Nathan; Keeney, J.G.; Jackson, Jay; Sikela, Megan; Raznahan, Armin; Giedd, Jay; Rapoport, Judith; Nagamani, Sandesh S.C.; Erez, Ayelet; Brunetti-Pierri, Nicola; Sugalski, Rachel; Lupski, James R.; Fingerlin, Tasha; Cheung, Sau Wai; Sikela, James M.

    2012-01-01

    DUF1220 domains show the largest human-lineage-specific increase in copy number of any protein-coding region in the human genome and map primarily to 1q21, where deletions and reciprocal duplications have been associated with microcephaly and macrocephaly, respectively. Given these findings and the high correlation between DUF1220 copy number and brain size across primate lineages (R2 = 0.98; p = 1.8 × 10−6), DUF1220 sequences represent plausible candidates for underlying 1q21-associated brain-size pathologies. To investigate this possibility, we used specialized bioinformatics tools developed for scoring highly duplicated DUF1220 sequences to implement targeted 1q21 array comparative genomic hybridization on individuals (n = 42) with 1q21-associated microcephaly and macrocephaly. We show that of all the 1q21 genes examined (n = 53), DUF1220 copy number shows the strongest association with brain size among individuals with 1q21-associated microcephaly, particularly with respect to the three evolutionarily conserved DUF1220 clades CON1(p = 0.0079), CON2 (p = 0.0134), and CON3 (p = 0.0116). Interestingly, all 1q21 DUF1220-encoding genes belonging to the NBPF family show significant correlations with frontal-occipital-circumference Z scores in the deletion group. In a similar survey of a nondisease population, we show that DUF1220 copy number exhibits the strongest correlation with brain gray-matter volume (CON1, p = 0.0246; and CON2, p = 0.0334). Notably, only DUF1220 sequences are consistently significant in both disease and nondisease populations. Taken together, these data strongly implicate the loss of DUF1220 copy number in the etiology of 1q21-associated microcephaly and support the view that DUF1220 domains function as general effectors of evolutionary, pathological, and normal variation in brain size. PMID:22901949

  12. DUF1220-domain copy number implicated in human brain-size pathology and evolution.

    PubMed

    Dumas, Laura J; O'Bleness, Majesta S; Davis, Jonathan M; Dickens, C Michael; Anderson, Nathan; Keeney, J G; Jackson, Jay; Sikela, Megan; Raznahan, Armin; Giedd, Jay; Rapoport, Judith; Nagamani, Sandesh S C; Erez, Ayelet; Brunetti-Pierri, Nicola; Sugalski, Rachel; Lupski, James R; Fingerlin, Tasha; Cheung, Sau Wai; Sikela, James M

    2012-09-01

    DUF1220 domains show the largest human-lineage-specific increase in copy number of any protein-coding region in the human genome and map primarily to 1q21, where deletions and reciprocal duplications have been associated with microcephaly and macrocephaly, respectively. Given these findings and the high correlation between DUF1220 copy number and brain size across primate lineages (R(2) = 0.98; p = 1.8 × 10(-6)), DUF1220 sequences represent plausible candidates for underlying 1q21-associated brain-size pathologies. To investigate this possibility, we used specialized bioinformatics tools developed for scoring highly duplicated DUF1220 sequences to implement targeted 1q21 array comparative genomic hybridization on individuals (n = 42) with 1q21-associated microcephaly and macrocephaly. We show that of all the 1q21 genes examined (n = 53), DUF1220 copy number shows the strongest association with brain size among individuals with 1q21-associated microcephaly, particularly with respect to the three evolutionarily conserved DUF1220 clades CON1(p = 0.0079), CON2 (p = 0.0134), and CON3 (p = 0.0116). Interestingly, all 1q21 DUF1220-encoding genes belonging to the NBPF family show significant correlations with frontal-occipital-circumference Z scores in the deletion group. In a similar survey of a nondisease population, we show that DUF1220 copy number exhibits the strongest correlation with brain gray-matter volume (CON1, p = 0.0246; and CON2, p = 0.0334). Notably, only DUF1220 sequences are consistently significant in both disease and nondisease populations. Taken together, these data strongly implicate the loss of DUF1220 copy number in the etiology of 1q21-associated microcephaly and support the view that DUF1220 domains function as general effectors of evolutionary, pathological, and normal variation in brain size. PMID:22901949

  13. Novel estimates of Aedes aegypti (Diptera: Culicidae) population size and adult survival based on Wolbachia releases.

    PubMed

    Ritchie, Scott A; Montgomery, Brian L; Hoffmann, Ary A

    2013-05-01

    The size of Aedes aegypti (L.) mosquito populations and adult survival rates have proven difficult to estimate because of a lack of consistent quantitative measures to equate sampling methods, such as adult trapping, to actual population size. However, such estimates are critical for devising control methods and for modeling the transmission of dengue and other infectious agents carried by this species. Here we take advantage of recent releases of Wolbachia-infected Ae. aegypti coupled with the results of ongoing monitoring to estimate the size of adult Ae. aegypti populations around Cairns in far north Queensland, Australia. Based on the association between released adults infected with Wolbachia and data from Biogents Sentinel traps, we show that data from two locations are consistent with population estimates of approximately 5-10 females per house and daily survival rates of 0.7-0.9 for the released Wolbachia-infected females. Moreover, we estimate that networks of Biogents Sentinel traps at a density of one per 15 houses capture around 5-10% of the adult population per week, and provide a rapid estimate of the absolute population size of Ae. aegypti. These data are discussed with respect to release rates and monitoring in future Wolbachia releases and also the levels of suppression required to reduce dengue transmission. PMID:23802459

  14. Tree allometry, leaf size and adult tree size in old-growth forests of western Oregon.

    PubMed

    King, D A

    1991-10-01

    Relationships between tree height and crown dimensions and trunk diameter were determined for shade-tolerant species of old-growth forests of western Oregon. The study included both understory and overstory species, deciduous and evergreen angiosperms and evergreen conifers. A comparison of adult understory species with sapling overstory species of similar height showed greater crown width and trunk diameter in the former, whether the comparison is made among conifers or deciduous trees. Conifer saplings had wider crowns than deciduous saplings, but the crown widths of the two groups converged with increase in tree height. Conifer saplings had thicker trunks than deciduous saplings of similar crown width, possibly because of selection for resistance to stem bending under snow loads. The results suggest that understory species have morphologies that increase light interception and persistence in the understory, whereas overstory species allocate their biomass for efficient height growth, thereby attaining the high-light environment of the canopy. The greater crown widths and the additional strength requirements imposed by snow loads on conifer saplings result in less height growth per biomass increment in conifer saplings than in deciduous saplings. However, the convergence in crown width of the two groups at heights greater than 20 m, and the proportionately smaller effect of snow loads on large trees, may result in older conifers equalling or surpassing deciduous trees in biomass allocation to height growth.

  15. Apolipoprotein ε4 is associated with lower brain volume in cognitively normal Chinese but not white older adults.

    PubMed

    Yokoyama, Jennifer S; Lee, Allen K L; Takada, Leonel T; Busovaca, Edgar; Bonham, Luke W; Chao, Steven Z; Tse, Marian; He, Jing; Schwarz, Christopher G; Carmichael, Owen T; Matthews, Brandy R; Karydas, Anna; Weiner, Michael W; Coppola, Giovanni; DeCarli, Charles S; Miller, Bruce L; Rosen, Howard J

    2015-01-01

    Studying ethnically diverse groups is important for furthering our understanding of biological mechanisms of disease that may vary across human populations. The ε4 allele of apolipoprotein E (APOE ε4) is a well-established risk factor for Alzheimer's disease (AD), and may confer anatomic and functional effects years before clinical signs of cognitive decline are observed. The allele frequency of APOE ε4 varies both across and within populations, and the size of the effect it confers for dementia risk may be affected by other factors. Our objective was to investigate the role APOE ε4 plays in moderating brain volume in cognitively normal Chinese older adults, compared to older white Americans. We hypothesized that carrying APOE ε4 would be associated with reduced brain volume and that the magnitude of this effect would be different between ethnic groups. We performed whole brain analysis of structural MRIs from Chinese living in America (n = 41) and Shanghai (n = 30) and compared them to white Americans (n = 71). We found a significant interaction effect of carrying APOE ε4 and being Chinese. The APOE ε4xChinese interaction was associated with lower volume in bilateral cuneus and left middle frontal gyrus (Puncorrected<0.001), with suggestive findings in right entorhinal cortex and left hippocampus (Puncorrected<0.01), all regions that are associated with neurodegeneration in AD. After correction for multiple testing, the left cuneus remained significantly associated with the interaction effect (PFWE = 0.05). Our study suggests there is a differential effect of APOE ε4 on brain volume in Chinese versus white cognitively normal elderly adults. This represents a novel finding that, if verified in larger studies, has implications for how biological, environmental and/or lifestyle factors may modify APOE ε4 effects on the brain in diverse populations. PMID:25738563

  16. Educating the adult brain: How the neuroscience of learning can inform educational policy

    NASA Astrophysics Data System (ADS)

    Knowland, Victoria C. P.; Thomas, Michael S. C.

    2014-05-01

    The acquisition of new skills in adulthood can positively affect an individual's quality of life, including their earning potential. In some cases, such as the learning of literacy in developing countries, it can provide an avenue to escape from poverty. In developed countries, job retraining in adulthood contributes to the flexibility of labour markets. For all adults, learning opportunities increase participation in society and family life. However, the popular view is that adults are less able to learn for an intrinsic reason: their brains are less plastic than in childhood. This article reviews what is currently known from neuroscientific research about how brain plasticity changes with age, with a particular focus on the ability to acquire new skills in adulthood. Anchoring their review in the examples of the adult acquisition of literacy and new motor skills, the authors address five specific questions: (1) Are sensitive periods in brain development relevant to learning complex educational skills like literacy? (2) Can adults become proficient in a new skill? (3) Can everyone learn equally effectively in adulthood? (4) What is the role of the learning environment? (5) Does adult education cost too much? They identify areas where further research is needed and conclude with a summary of principles for enhancing adult learning now established on a neuroscience foundation.

  17. Vitamin D as a neurosteroid affecting the developing and adult brain.

    PubMed

    Groves, Natalie J; McGrath, John J; Burne, Thomas H J

    2014-01-01

    Vitamin D deficiency is prevalent throughout the world, and growing evidence supports a requirement for optimal vitamin D levels for the healthy developing and adult brain. Vitamin D has important roles in proliferation and differentiation, calcium signaling within the brain, and neurotrophic and neuroprotective actions; it may also alter neurotransmission and synaptic plasticity. Recent experimental studies highlight the impact that vitamin D deficiency has on brain function in health and disease. In addition, results from recent animal studies suggest that vitamin D deficiency during adulthood may exacerbate underlying brain disorders and/or worsen recovery from brain stressors. An increasing number of epidemiological studies indicate that vitamin D deficiency is associated with a wide range of neuropsychiatric disorders and neurodegenerative diseases. Vitamin D supplementation is readily available and affordable, and this review highlights the need for further research. PMID:25033060

  18. Fetal Alcohol Exposure Reduces Adult Brain Plasticity. Science Briefs

    ERIC Educational Resources Information Center

    National Scientific Council on the Developing Child, 2007

    2007-01-01

    "Science Briefs" summarize the findings and implications of a recent study in basic science or clinical research. This Brief summarizes the findings and implications of "Moderate Fetal Alcohol Exposure Impairs the Neurogenic Response to an Enriched Environment in Adult Mice" (I. Y. Choi; A. M. Allan; and L. A. Cunningham). Observations of mice…

  19. [Management of swallowing disorders after brain injuries in adults].

    PubMed

    Fichaux, Bourin P; Labrune, M

    2008-01-01

    The management of swallowing disorders after brain injury must be soon as well. The physiopathological analysis and the organization of the therapeutic project of these patients require the intervention of an interdisciplinary team. Dysphagia falls under a complex clinical context associating impairments of cognition, communication and behavioural control. The management associates speech therapist, caregivers, otolaryngolologist, phoniatrician, physiotherapist and nutritional therapist without forgetting the family circle. The fluctuations of consciousness and concentration of our patients brings us to constantly readjusting and rehabilitating the strategies of feeding. Obstacles with their evolution towards a normal feeding are akinesia, limits of motor functions, impairements of cognition and behavioural control. In the located lesions swallow recovers can be fast, instead of in severe brain-injury the challenge is to ensure safe and adequate nutrition, using a variety of strategies depending on the presenting symptoms. The purpose of this article is to relate our experience beside patients with an acute or recent cerbrovascular event.

  20. Structural and functional rich club organization of the brain in children and adults.

    PubMed

    Grayson, David S; Ray, Siddharth; Carpenter, Samuel; Iyer, Swathi; Dias, Taciana G Costa; Stevens, Corinne; Nigg, Joel T; Fair, Damien A

    2014-01-01

    Recent studies using Magnetic Resonance Imaging (MRI) have proposed that the brain's white matter is organized as a rich club, whereby the most highly connected regions of the brain are also highly connected to each other. Here we use both functional and diffusion-weighted MRI in the human brain to investigate whether the rich club phenomena is present with functional connectivity, and how this organization relates to the structural phenomena. We also examine whether rich club regions serve to integrate information between distinct brain systems, and conclude with a brief investigation of the developmental trajectory of rich-club phenomena. In agreement with prior work, both adults and children showed robust structural rich club organization, comprising regions of the superior medial frontal/dACC, medial parietal/PCC, insula, and inferior temporal cortex. We also show that these regions were highly integrated across the brain's major networks. Functional brain networks were found to have rich club phenomena in a similar spatial layout, but a high level of segregation between systems. While no significant differences between adults and children were found structurally, adults showed significantly greater functional rich club organization. This difference appeared to be driven by a specific set of connections between superior parietal, insula, and supramarginal cortex. In sum, this work highlights the existence of both a structural and functional rich club in adult and child populations with some functional changes over development. It also offers a potential target in examining atypical network organization in common developmental brain disorders, such as ADHD and Autism.

  1. Amphetamine modulates brain signal variability and working memory in younger and older adults.

    PubMed

    Garrett, Douglas D; Nagel, Irene E; Preuschhof, Claudia; Burzynska, Agnieszka Z; Marchner, Janina; Wiegert, Steffen; Jungehülsing, Gerhard J; Nyberg, Lars; Villringer, Arno; Li, Shu-Chen; Heekeren, Hauke R; Bäckman, Lars; Lindenberger, Ulman

    2015-06-16

    Better-performing younger adults typically express greater brain signal variability relative to older, poorer performers. Mechanisms for age and performance-graded differences in brain dynamics have, however, not yet been uncovered. Given the age-related decline of the dopamine (DA) system in normal cognitive aging, DA neuromodulation is one plausible mechanism. Hence, agents that boost systemic DA [such as d-amphetamine (AMPH)] may help to restore deficient signal variability levels. Furthermore, despite the standard practice of counterbalancing drug session order (AMPH first vs. placebo first), it remains understudied how AMPH may interact with practice effects, possibly influencing whether DA up-regulation is functional. We examined the effects of AMPH on functional-MRI-based blood oxygen level-dependent (BOLD) signal variability (SD(BOLD)) in younger and older adults during a working memory task (letter n-back). Older adults expressed lower brain signal variability at placebo, but met or exceeded young adult SD(BOLD) levels in the presence of AMPH. Drug session order greatly moderated change-change relations between AMPH-driven SD(BOLD) and reaction time means (RT(mean)) and SDs (RT(SD)). Older adults who received AMPH in the first session tended to improve in RT(mean) and RT(SD) when SD(BOLD) was boosted on AMPH, whereas younger and older adults who received AMPH in the second session showed either a performance improvement when SD(BOLD) decreased (for RT(mean)) or no effect at all (for RT(SD)). The present findings support the hypothesis that age differences in brain signal variability reflect aging-induced changes in dopaminergic neuromodulation. The observed interactions among AMPH, age, and session order highlight the state- and practice-dependent neurochemical basis of human brain dynamics.

  2. Brain tissue pressure measurements in perinatal and adult rabbits.

    PubMed

    Hornig, G W; Lorenzo, A V; Zavala, L M; Welch, K

    1987-12-01

    Brain tissue pressure (BTP) in pre- and post-natal anesthetized rabbits, held in a stereotactic head holder, was measured with a fluid filled 23 gauge open-ended cannula connected distally to a pressure transducer. By advancing the cannula step wise through a hole in the cranium it was possible to sequentially measure pressure from the cranial subarachnoid space, cortex, ventricle and basal ganglia. Separate cannulas and transducers were used to measure CSFP from the cisterna magna and arterial and/or venous pressure. Pressure recordings obtained when the tip of the BTP cannula was located in the cranial subarachnoid space or ventricle exhibited respiratory and blood pressure pulsations equivalent to and in phase with CSF pulsations recorded from the cisterna magna. When the tip was advanced into brain parenchymal sites such pulsations were suppressed or non-detectable unless communication with a CSF compartment had been established inadvertently. Although CSF pressures in the three spinal fluid compartments were equivalent, in most animals BTP was higher than CSFP. However, after momentary venting of the system BTP equilibrated at a pressure below that of CSFP. We speculate that venting of the low compliance system (1.20 x 10(-5) ml/mmHg) relieves the isometric pressure build-up due to insertion of the cannula into brain parenchyma. Under these conditions, and at all ages examined, BTP in the rabbit is consistently lower than CSFP and, as with CSFP, it increases as the animal matures.

  3. Chimpanzee and felid diet composition is influenced by prey brain size.

    PubMed

    Shultz, Susanne; Dunbar, R I M

    2006-12-22

    Prey use a wide variety of anti-predator defence strategies, including morphological and chemical defences as well as behavioural traits (risk-modulated habitat use, changes in activity patterns, foraging decisions and group living). The critical test of how effective anti-predator strategies are is to relate them to relative indices of mortality across predators. Here, we compare biases in predator diet composition with prey characteristics and show that chimpanzee (Pan troglodytes) and felid show the strongest and the most consistent predator bias towards small-brained prey. We propose that large-brained prey are likely to be more effective at evading predators because they can effectively alter their behavioural responses to specific predator encounters. Thus, we provide evidence for the hypothesis that brain size evolution is potentially driven by selection for more sophisticated and behaviourally flexible anti-predator strategies.

  4. Daily Marijuana Use Is Not Associated with Brain Morphometric Measures in Adolescents or Adults

    PubMed Central

    Thayer, Rachel E.; Depue, Brendan E.; Sabbineni, Amithrupa; Bryan, Angela D.; Hutchison, Kent E.

    2015-01-01

    Recent research has suggested that marijuana use is associated with volumetric and shape differences in subcortical structures, including the nucleus accumbens and amygdala, in a dose-dependent fashion. Replication of such results in well controlled studies is essential to clarify the effects of marijuana. To that end, this retrospective study examined brain morphology in a sample of adult daily marijuana users (n = 29) versus nonusers (n = 29) and a sample of adolescent daily users (n = 50) versus nonusers (n = 50). Groups were matched on a critical confounding variable, alcohol use, to a far greater degree than in previously published studies. We acquired high-resolution MRI scans, and investigated group differences in gray matter using voxel-based morphometry, surface-based morphometry, and shape analysis in structures suggested to be associated with marijuana use, as follows: the nucleus accumbens, amygdala, hippocampus, and cerebellum. No statistically significant differences were found between daily users and nonusers on volume or shape in the regions of interest. Effect sizes suggest that the failure to find differences was not due to a lack of statistical power, but rather was due to the lack of even a modest effect. In sum, the results indicate that, when carefully controlling for alcohol use, gender, age, and other variables, there is no association between marijuana use and standard volumetric or shape measurements of subcortical structures. PMID:25632127

  5. Adult and larval traits as determinants of geographic range size among tropical reef fishes

    PubMed Central

    Luiz, Osmar J.; Allen, Andrew P.; Robertson, D. Ross; Floeter, Sergio R.; Kulbicki, Michel; Vigliola, Laurent; Becheler, Ronan; Madin, Joshua S.

    2013-01-01

    Most marine organisms disperse via ocean currents as larvae, so it is often assumed that larval-stage duration is the primary determinant of geographic range size. However, empirical tests of this relationship have yielded mixed results, and alternative hypotheses have rarely been considered. Here we assess the relative influence of adult and larval-traits on geographic range size using a global dataset encompassing 590 species of tropical reef fishes in 47 families, the largest compilation of such data to date for any marine group. We analyze this database using linear mixed-effect models to control for phylogeny and geographical limits on range size. Our analysis indicates that three adult traits likely to affect the capacity of new colonizers to survive and establish reproductive populations (body size, schooling behavior, and nocturnal activity) are equal or better predictors of geographic range size than pelagic larval duration. We conclude that adult life-history traits that affect the postdispersal persistence of new populations are primary determinants of successful range extension and, consequently, of geographic range size among tropical reef fishes. PMID:24065830

  6. Adult and larval traits as determinants of geographic range size among tropical reef fishes.

    PubMed

    Luiz, Osmar J; Allen, Andrew P; Robertson, D Ross; Floeter, Sergio R; Kulbicki, Michel; Vigliola, Laurent; Becheler, Ronan; Madin, Joshua S

    2013-10-01

    Most marine organisms disperse via ocean currents as larvae, so it is often assumed that larval-stage duration is the primary determinant of geographic range size. However, empirical tests of this relationship have yielded mixed results, and alternative hypotheses have rarely been considered. Here we assess the relative influence of adult and larval-traits on geographic range size using a global dataset encompassing 590 species of tropical reef fishes in 47 families, the largest compilation of such data to date for any marine group. We analyze this database using linear mixed-effect models to control for phylogeny and geographical limits on range size. Our analysis indicates that three adult traits likely to affect the capacity of new colonizers to survive and establish reproductive populations (body size, schooling behavior, and nocturnal activity) are equal or better predictors of geographic range size than pelagic larval duration. We conclude that adult life-history traits that affect the postdispersal persistence of new populations are primary determinants of successful range extension and, consequently, of geographic range size among tropical reef fishes.

  7. Molecular evolution of the brain size regulator genes CDK5RAP2 and CENPJ.

    PubMed

    Evans, Patrick D; Vallender, Eric J; Lahn, Bruce T

    2006-06-21

    Primary microcephaly is a developmental defect of the brain characterized by severely reduced brain size but an absence of other overt abnormalities. Mutations in several loci have been linked to primary microcephaly. The underlying genes for two of these were recently identified as CDK5RAP2 and CENPJ. Here, we focus on CDK5RAP2 and show that the protein evolutionary rate of this gene is significantly higher in primates than rodents or carnivores. We further show that the evolutionary rate within primates is particularly high in the human and chimpanzee terminal branches. Thus, the pattern of molecular evolution seen in CDK5RAP2 appears to parallel, at least approximately, that seen in two other previously identified primary microcephaly genes, microcephalin and ASPM. We also briefly discuss CENPJ, which similarly exhibits higher rate of protein evolution in primates as compared to rodents and carnivores. Together, the evolutionary patterns of all four presently known primary microcephaly genes are consistent with the hypothesis that genes regulating brain size during development might also play a role in brain evolution in primates and especially humans. PMID:16631324

  8. Temporal assessment of nanoparticle accumulation after experimental brain injury: Effect of particle size

    PubMed Central

    Bharadwaj, Vimala N.; Lifshitz, Jonathan; Adelson, P. David; Kodibagkar, Vikram D.; Stabenfeldt, Sarah E.

    2016-01-01

    Nanoparticle (NP) based therapeutic and theranostic agents have been developed for various diseases, yet application to neural disease/injury is restricted by the blood-brain-barrier (BBB). Traumatic brain injury (TBI) results in a host of pathological alterations, including transient breakdown of the BBB, thus opening a window for NP delivery to the injured brain tissue. This study focused on investigating the spatiotemporal accumulation of different sized NPs after TBI. Specifically, animal cohorts sustaining a controlled cortical impact injury received an intravenous injection of PEGylated NP cocktail (20, 40, 100, and 500 nm, each with a unique fluorophore) immediately (0 h), 2 h, 5 h, 12 h, or 23 h after injury. NPs were allowed to circulate for 1 h before perfusion and brain harvest. Confocal microscopy demonstrated peak NP accumulation within the injury penumbra 1 h post-injury. An inverse relationship was found between NP size and their continued accumulation within the penumbra. NP accumulation preferentially occurred in the primary motor and somatosensory areas of the injury penumbra as compared to the parietal association and visual area. Thus, we characterized the accumulation of particles up to 500 nm at different times acutely after injury, indicating the potential of NP-based TBI theranostics in the acute period after injury. PMID:27444615

  9. Microcephaly disease gene Wdr62 regulates mitotic progression of embryonic neural stem cells and brain size.

    PubMed

    Chen, Jian-Fu; Zhang, Ying; Wilde, Jonathan; Hansen, Kirk C; Lai, Fan; Niswander, Lee

    2014-05-30

    Human genetic studies have established a link between a class of centrosome proteins and microcephaly. Current studies of microcephaly focus on defective centrosome/spindle orientation. Mutations in WDR62 are associated with microcephaly and other cortical abnormalities in humans. Here we create a mouse model of Wdr62 deficiency and find that the mice exhibit reduced brain size due to decreased neural progenitor cells (NPCs). Wdr62 depleted cells show spindle instability, spindle assembly checkpoint (SAC) activation, mitotic arrest and cell death. Mechanistically, Wdr62 associates and genetically interacts with Aurora A to regulate spindle formation, mitotic progression and brain size. Our results suggest that Wdr62 interacts with Aurora A to control mitotic progression, and loss of these interactions leads to mitotic delay and cell death of NPCs, which could be a potential cause of human microcephaly.

  10. Adding chemo after radiation treatment improves survival for adults with a type of brain tumor

    Cancer.gov

    Adults with low-grade gliomas, a form of brain tumor, who received chemotherapy following completion of radiation therapy lived longer than patients who received radiation therapy alone, according to long-term follow-up results from a NIH-supported random

  11. Minimal Brain Dysfunction in Childhood: 1. Outcome in Late Adolescence and Early Adult Years. Final Version.

    ERIC Educational Resources Information Center

    Milman, Doris H.

    Seventy-three patients, diagnosed in childhood as having either maturational lag or organic brain syndrome, were followed for an average of 12 years into late adolescence and early adult life for the purpose of discovering the outcome with respect to ultimate psychiatric status, educational attainment, social adjustment, and global adjustment. At…

  12. Brain Mapping of Language and Auditory Perception in High-Functioning Autistic Adults: A PET Study.

    ERIC Educational Resources Information Center

    Muller, R-A.; Behen, M. E.; Rothermel, R. D.; Chugani, D. C.; Muzik, O.; Mangner, T. J.; Chugani, H. T.

    1999-01-01

    A study used positron emission tomography (PET) to study patterns of brain activation during auditory processing in five high-functioning adults with autism. Results found that participants showed reversed hemispheric dominance during the verbal auditory stimulation and reduced activation of the auditory cortex and cerebellum. (CR)

  13. Humor, Rapport, and Uncomfortable Moments in Interactions with Adults with Traumatic Brain Injury

    ERIC Educational Resources Information Center

    Kovarsky, Dana; Schiemer, Christine; Murray, Allison

    2011-01-01

    We examined uncomfortable moments that damaged rapport during group interactions between college students in training to become speech-language pathologists and adults with traumatic brain injury. The students worked as staff in a community-based program affiliated with a university training program that functioned as a recreational gathering…

  14. Radial glia-like cells persist in the adult rat brain.

    PubMed

    Gubert, Fernanda; Zaverucha-do-Valle, Camila; Pimentel-Coelho, Pedro M; Mendez-Otero, Rosalia; Santiago, Marcelo F

    2009-03-01

    During development, radial glia cells contribute to neuronal migration and neurogenesis, and differentiate into astrocytes by the end of the developmental period. Recently, it was demonstrated that during development, radial glia cells, in addition to their role in migration, also give rise to neuroblasts. Furthermore, radial glial cells remain in the adult brain as adult neural stem cells (NSC) in the subventricular zone (SVZ) around the lateral ventricles (LVs), and generate new neurons continuously throughout adulthood. In this study, we used immunohistochemical and morphological methods to investigate the presence of radial glia-like cells around the LVs during the postnatal development period until adulthood in rats. In all ages of rats studied, we identified cells with morphological and immunocytochemical features that are similar to the radial glia cells found in the embryonic brain. Similarly to the radial glia, these cells express nestin and vimentin, and have a radial morphology, extending perpendicularly as processes from the ventricle wall. These cells also express GFAP, GLAST, and Pax6, and proliferate. In the brains of adult rats, we identified cells with relatively long processes (up to 600 mum) in close apposition with migrating neuroblasts. Our results showed that the radial glia-like cells present in the adult rat brain share several morphological and functional characteristics with the embryonic radial glia. We suggest that the embryonic radial glia cells located around the LV walls do not complete their transformation into astrocytes, but rather persist in adulthood.

  15. Disrupted-In-Schizophrenia 1 regulates integration of newly generated neurons in the adult brain

    PubMed Central

    Duan, Xin; Chang, Jay H.; Ge, Shaoyu; Faulkner, Regina L.; Kim, Ju Young; Kitabatake, Yasuji; Liu, Xiao-bo; Yang, Chih-Hao; Jordan, J. Dedrick; Ma, Dengke K.; Liu, Cindy Y.; Ganesan, Sundar; Cheng, Hwai-Jong; Ming, Guo-li; Lu, Bai; Song, Hongjun

    2007-01-01

    Summary Adult neurogenesis occurs throughout life in discrete regions of the adult mammalian brain. Little is known about the mechanism governing the sequential developmental process that leads to integration of new neurons from adult neural stem cells into the existing circuitry. Here, we investigated roles of Disrupted-In-Schizophrenia 1 (DISC1), a schizophrenia susceptibility gene, in adult hippocampal neurogenesis. Unexpectedly, down regulation of DISC1 leads to accelerated neuronal integration, resulting in aberrant morphological development and mis-positioning of new dentate granule cells in a cell-autonomous fashion. Functionally, newborn neurons with DISC1 knockdown exhibit enhanced excitability and accelerated dendritic development and synapse formation. Furthermore, DISC1 cooperates with its binding partner Ndel1 in regulating adult neurogenesis. Taken together, our study identifies DISC1 as a key regulator that orchestrates the tempo of functional neuronal integration in the adult brain and demonstrates essential roles of a susceptibility gene for major mental illness in neuronal development, including adult neurogenesis. PMID:17825401

  16. [Specific features of rhino-sinusogenic brain abscesses in adults and children].

    PubMed

    Blagoveshchenskaia, N S; Mukhamedzhanov, N Z

    1989-01-01

    Analysis of observations of 49 patients with rhinosinusogenic brain abscesses revealed differences in their development between adults and children. This pathology occurs in adults more frequently than in children, particularly young children. In adults, brain abscesses usually develop as a result of chronic frontal- or polysinusitis, while in children they typically occur after maxillary sinusitis and in early age children also after acute suppuration in the nasal cavity. For adults, the contact pathway of infection is characteristic, whereas for children, the hematogenic-metastatic pathway is typical. Adults show single abscesses while children show both single, multiple and multichamber abscesses accompanied by separation of cranial sutures, thinning of calvaria, and protrusion and tension of the cranial fontanel. In children, abscesses may grow very large. In adults, the hypertensive syndrome is very distinct, while in children, the hydrocephalic-hypertensive syndrome comes to the foreground. In children, infectious-toxic symptoms are more significant. In adults, focal neurological symptoms become more serious than in children in whom they are also more labile.

  17. Structural brain correlates of associative memory in older adults.

    PubMed

    Becker, Nina; Laukka, Erika J; Kalpouzos, Grégoria; Naveh-Benjamin, Moshe; Bäckman, Lars; Brehmer, Yvonne

    2015-09-01

    Associative memory involves binding two or more items into a coherent memory episode. Relative to memory for single items, associative memory declines greatly in aging. However, older individuals vary substantially in their ability to memorize associative information. Although functional studies link associative memory to the medial temporal lobe (MTL) and prefrontal cortex (PFC), little is known about how volumetric differences in MTL and PFC might contribute to individual differences in associative memory. We investigated regional gray-matter volumes related to individual differences in associative memory in a sample of healthy older adults (n=54; age=60years). To differentiate item from associative memory, participants intentionally learned face-scene picture pairs before performing a recognition task that included single faces, scenes, and face-scene pairs. Gray-matter volumes were analyzed using voxel-based morphometry region-of-interest (ROI) analyses. To examine volumetric differences specifically for associative memory, item memory was controlled for in the analyses. Behavioral results revealed large variability in associative memory that mainly originated from differences in false-alarm rates. Moreover, associative memory was independent of individuals' ability to remember single items. Older adults with better associative memory showed larger gray-matter volumes primarily in regions of the left and right lateral PFC. These findings provide evidence for the importance of PFC in intentional learning of associations, likely because of its involvement in organizational and strategic processes that distinguish older adults with good from those with poor associative memory.

  18. Plausible mechanisms for brain structural and size changes in human evolution.

    PubMed

    Blazek, Vladimir; Brùzek, Jaroslav; Casanova, Manuel F

    2011-09-01

    Encephalization has many contexts and implications. On one hand, it is concerned with the transformation of eating habits, social relationships and communication, cognitive skills and the mind. Along with the increase in brain size on the other hand, encephalization is connected with the creation of more complex brain structures, namely in the cerebral cortex. It is imperative to inquire into the mechanisms which are linked with brain growth and to find out which of these mechanisms allow it and determine it. There exist a number of theories for understanding human brain evolution which originate from neurological sciences. These theories are the concept of radial units, minicolumns, mirror neurons, and neurocognitive networks. Over the course of evolution, it is evident that a whole range of changes have taken place in regards to heredity. These changes include new mutations of genes in the microcephalin complex, gene duplications, gene co-expression, and genomic imprinting. This complex study of the growth and reorganization of the brain and the functioning of hereditary factors and their external influences creates an opportunity to consider the implications of cultural evolution and cognitive faculties.

  19. Surfactants, not size or zeta-potential influence blood-brain barrier passage of polymeric nanoparticles.

    PubMed

    Voigt, Nadine; Henrich-Noack, Petra; Kockentiedt, Sarah; Hintz, Werner; Tomas, Jürgen; Sabel, Bernhard A

    2014-05-01

    Nanoparticles (NP) can deliver drugs across the blood-brain barrier (BBB), but little is known which of the factors surfactant, size and zeta-potential are essential for allowing BBB passage. To this end we designed purpose-built fluorescent polybutylcyanoacrylate (PBCA) NP and imaged the NP's passage over the blood-retina barrier - which is a model of the BBB - in live animals. Rats received intravenous injections of fluorescent PBCA-NP fabricated by mini-emulsion polymerisation to obtain various NP's compositions that varied in surfactants (non-ionic, anionic, cationic), size (67-464nm) and zeta-potential. Real-time imaging of retinal blood vessels and retinal tissue was carried out with in vivo confocal neuroimaging (ICON) before, during and after NP's injection. Successful BBB passage with subsequent cellular labelling was achieved if NP were fabricated with non-ionic surfactants or cationic stabilizers but not when anionic compounds were added. NP's size and charge had no influence on BBB passage and cell labelling. This transport was not caused by an unspecific opening of the BBB because control experiments with injections of unlabelled NP and fluorescent dye (to test a "door-opener" effect) did not lead to parenchymal labelling. Thus, neither NP's size nor chemo-electric charge, but particle surface is the key factor determining BBB passage. This result has important implications for NP engineering in medicine: depending on the surfactant, NP can serve one of two opposite functions: while non-ionic tensides enhance brain up-take, addition of anionic tensides prevents it. NP can now be designed to specifically enhance drug delivery to the brain or, alternatively, to prevent brain penetration so to reduce unwanted psychoactive effects of drugs or prevent environmental nanoparticles from entering tissue of the central nervous system. PMID:24607790

  20. 46 CFR 160.171-17 - Approval testing for adult size immersion suit.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Approval testing for adult size immersion suit. Caution: During each of the in-water tests prescribed in this section, a person ready to render assistance when needed should be near each subject in the water... being immersed in water at 5 °C (41 °F) for a period of one hour, each subject must be able to pick up...

  1. 46 CFR 160.171-17 - Approval testing for adult size immersion suit.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Approval testing for adult size immersion suit. Caution: During each of the in-water tests prescribed in this section, a person ready to render assistance when needed should be near each subject in the water... being immersed in water at 5 °C (41 °F) for a period of one hour, each subject must be able to pick up...

  2. Shedding New Light on an Old Problem: The Estimation of Shadow Sizes in Children and Adults

    ERIC Educational Resources Information Center

    Ebersbach, Mirjam; Resing, Wilma C. M.

    2007-01-01

    Two experiments using the "projection of shadows" paradigm investigated multidimensional reasoning, implicit and explicit knowledge, and the nonlinearity concept in 5-, 9-, and 13-year-olds and adults. Participants estimated the resulting shadow lengths of differently sized objects, placed at varying distances from a light source. Experiment 1…

  3. Traumatic Brain Injury Activation of the Adult Subventricular Zone Neurogenic Niche.

    PubMed

    Chang, Eun Hyuk; Adorjan, Istvan; Mundim, Mayara V; Sun, Bin; Dizon, Maria L V; Szele, Francis G

    2016-01-01

    Traumatic brain injury (TBI) is common in both civilian and military life, placing a large burden on survivors and society. However, with the recognition of neural stem cells in adult mammals, including humans, came the possibility to harness these cells for repair of damaged brain, whereas previously this was thought to be impossible. In this review, we focus on the rodent adult subventricular zone (SVZ), an important neurogenic niche within the mature brain in which neural stem cells continue to reside. We review how the SVZ is perturbed following various animal TBI models with regards to cell proliferation, emigration, survival, and differentiation, and we review specific molecules involved in these processes. Together, this information suggests next steps in attempting to translate knowledge from TBI animal models into human therapies for TBI. PMID:27531972

  4. Environment matters: synaptic properties of neurons born in the epileptic adult brain develop to reduce excitability.

    PubMed

    Jakubs, Katherine; Nanobashvili, Avtandil; Bonde, Sara; Ekdahl, Christine T; Kokaia, Zaal; Kokaia, Merab; Lindvall, Olle

    2006-12-21

    Neural progenitors in the adult dentate gyrus continuously produce new functional granule cells. Here we used whole-cell patch-clamp recordings to explore whether a pathological environment influences synaptic properties of new granule cells labeled with a GFP-retroviral vector. Rats were exposed to a physiological stimulus, i.e., running, or a brain insult, i.e., status epilepticus, which gave rise to neuronal death, inflammation, and chronic seizures. Granule cells formed after these stimuli exhibited similar intrinsic membrane properties. However, the new neurons born into the pathological environment differed with respect to synaptic drive and short-term plasticity of both excitatory and inhibitory afferents. The new granule cells formed in the epileptic brain exhibited functional connectivity consistent with reduced excitability. We demonstrate a high degree of plasticity in synaptic inputs to adult-born new neurons, which could act to mitigate pathological brain function.

  5. Traumatic Brain Injury Activation of the Adult Subventricular Zone Neurogenic Niche

    PubMed Central

    Chang, Eun Hyuk; Adorjan, Istvan; Mundim, Mayara V.; Sun, Bin; Dizon, Maria L. V.; Szele, Francis G.

    2016-01-01

    Traumatic brain injury (TBI) is common in both civilian and military life, placing a large burden on survivors and society. However, with the recognition of neural stem cells in adult mammals, including humans, came the possibility to harness these cells for repair of damaged brain, whereas previously this was thought to be impossible. In this review, we focus on the rodent adult subventricular zone (SVZ), an important neurogenic niche within the mature brain in which neural stem cells continue to reside. We review how the SVZ is perturbed following various animal TBI models with regards to cell proliferation, emigration, survival, and differentiation, and we review specific molecules involved in these processes. Together, this information suggests next steps in attempting to translate knowledge from TBI animal models into human therapies for TBI. PMID:27531972

  6. [Regulation of neurogenesis: factors affecting of new neurons formation in adult mammals brain].

    PubMed

    Respondek, Michalina; Buszman, Ewa

    2015-12-31

    Neurogenesis is a complex and multi-step process of generating completely functional neurons. This process in adult brain is based on pluripotentional neuronal stem cells (NSC), which are able to proliferation and differentiation into mature neurons or glial cells. NSC are located in subgranular zone inside hippocampus and in subventricular zone. The new neurons formation depends on many endo- and exogenous factors which modulate each step of neurogenesis. This article describes the most important regulators of adult neurogenesis, mainly: neurotrophins, growth factors, hormones, neurotransmitters and microenvironment of NSC. Some drugs, especially antipsychotics, antidepressants and normothymics may affect the neurogenic properties of adult brain. Moreover pathological processes such as neuroinflammation, stroke or epilepsy are able to induce proliferation of NSC. The proneurogenic effects of psychotropic drugs and pathological processes are associated with their ability to increase some hormones and neurotrophins level, as well as with rising the expression of antiapoptotic Bcl-2 protein and metalloproteinase MMP-2. Additionaly, some drugs, for example haloperidol, are able to block prolactin and dopaminergic neuroblasts receptors. Down-regulation of adult neurogenesis is associated with alcohol abuse and high stress level. Negative effect of many drugs, such as cytostatics, COX-2 inhibitors and opioides was also observed. The proneurogenic effect of described factors suggest their broad therapeutic potential and gives a new perspective on an effective and modern treatment of many neuropsychiatric disorders. This effect can also help to clarify the pathogenesis of disorders associated with proliferation and degeneration of adult brain cells.

  7. Transcriptional profiling of adult neural stem-like cells from the human brain.

    PubMed

    Sandberg, Cecilie Jonsgar; Vik-Mo, Einar O; Behnan, Jinan; Helseth, Eirik; Langmoen, Iver A

    2014-01-01

    There is a great potential for the development of new cell replacement strategies based on adult human neural stem-like cells. However, little is known about the hierarchy of cells and the unique molecular properties of stem- and progenitor cells of the nervous system. Stem cells from the adult human brain can be propagated and expanded in vitro as free floating neurospheres that are capable of self-renewal and differentiation into all three cell types of the central nervous system. Here we report the first global gene expression study of adult human neural stem-like cells originating from five human subventricular zone biopsies (mean age 42, range 33-60). Compared to adult human brain tissue, we identified 1,189 genes that were significantly up- and down-regulated in adult human neural stem-like cells (1% false discovery rate). We found that adult human neural stem-like cells express stem cell markers and have reduced levels of markers that are typical of the mature cells in the nervous system. We report that the genes being highly expressed in adult human neural stem-like cells are associated with developmental processes and the extracellular region of the cell. The calcium signaling pathway and neuroactive ligand-receptor interactions are enriched among the most differentially regulated genes between adult human neural stem-like cells and adult human brain tissue. We confirmed the expression of 10 of the most up-regulated genes in adult human neural stem-like cells in an additional sample set that included adult human neural stem-like cells (n = 6), foetal human neural stem cells (n = 1) and human brain tissues (n = 12). The NGFR, SLITRK6 and KCNS3 receptors were further investigated by immunofluorescence and shown to be heterogeneously expressed in spheres. These receptors could potentially serve as new markers for the identification and characterisation of neural stem- and progenitor cells or as targets for manipulation of cellular fate.

  8. Transcriptional Profiling of Adult Neural Stem-Like Cells from the Human Brain

    PubMed Central

    Sandberg, Cecilie Jonsgar; Vik-Mo, Einar O.; Behnan, Jinan; Helseth, Eirik; Langmoen, Iver A.

    2014-01-01

    There is a great potential for the development of new cell replacement strategies based on adult human neural stem-like cells. However, little is known about the hierarchy of cells and the unique molecular properties of stem- and progenitor cells of the nervous system. Stem cells from the adult human brain can be propagated and expanded in vitro as free floating neurospheres that are capable of self-renewal and differentiation into all three cell types of the central nervous system. Here we report the first global gene expression study of adult human neural stem-like cells originating from five human subventricular zone biopsies (mean age 42, range 33–60). Compared to adult human brain tissue, we identified 1,189 genes that were significantly up- and down-regulated in adult human neural stem-like cells (1% false discovery rate). We found that adult human neural stem-like cells express stem cell markers and have reduced levels of markers that are typical of the mature cells in the nervous system. We report that the genes being highly expressed in adult human neural stem-like cells are associated with developmental processes and the extracellular region of the cell. The calcium signaling pathway and neuroactive ligand-receptor interactions are enriched among the most differentially regulated genes between adult human neural stem-like cells and adult human brain tissue. We confirmed the expression of 10 of the most up-regulated genes in adult human neural stem-like cells in an additional sample set that included adult human neural stem-like cells (n = 6), foetal human neural stem cells (n = 1) and human brain tissues (n = 12). The NGFR, SLITRK6 and KCNS3 receptors were further investigated by immunofluorescence and shown to be heterogeneously expressed in spheres. These receptors could potentially serve as new markers for the identification and characterisation of neural stem- and progenitor cells or as targets for manipulation of cellular fate. PMID

  9. Quantitative Expression Profile of Distinct Functional Regions in the Adult Mouse Brain

    PubMed Central

    Nagano, Mamoru; Uno, Kenichiro D.; Tsujino, Kaori; Hanashima, Carina; Shigeyoshi, Yasufumi; Ueda, Hiroki R.

    2011-01-01

    The adult mammalian brain is composed of distinct regions with specialized roles including regulation of circadian clocks, feeding, sleep/awake, and seasonal rhythms. To find quantitative differences of expression among such various brain regions, we conducted the BrainStars (B*) project, in which we profiled the genome-wide expression of ∼50 small brain regions, including sensory centers, and centers for motion, time, memory, fear, and feeding. To avoid confounds from temporal differences in gene expression, we sampled each region every 4 hours for 24 hours, and pooled the samples for DNA-microarray assays. Therefore, we focused on spatial differences in gene expression. We used informatics to identify candidate genes with expression changes showing high or low expression in specific regions. We also identified candidate genes with stable expression across brain regions that can be used as new internal control genes, and ligand-receptor interactions of neurohormones and neurotransmitters. Through these analyses, we found 8,159 multi-state genes, 2,212 regional marker gene candidates for 44 small brain regions, 915 internal control gene candidates, and 23,864 inferred ligand-receptor interactions. We also found that these sets include well-known genes as well as novel candidate genes that might be related to specific functions in brain regions. We used our findings to develop an integrated database (http://brainstars.org/) for exploring genome-wide expression in the adult mouse brain, and have made this database openly accessible. These new resources will help accelerate the functional analysis of the mammalian brain and the elucidation of its regulatory network systems. PMID:21858037

  10. A simple non-invasive method for measuring gross brain size in small live fish with semi-transparent heads

    PubMed Central

    2014-01-01

    This paper describes a non-invasive method for estimating gross brain size in small fish with semi-transparent heads, using system camera equipment. Macro-photographs were taken from above on backlit free-swimming fish undergoing light anaesthesia. From the photographs, the width of the optic tectum was measured. This measure (TeO-measure) correlates well with the width of the optic tectum as measured from out-dissected brains in both brown trout fry and zebrafish (Pearson r > 0.90). The TeO-measure also correlates well with overall brain wet weight in brown trout fry (r = 0.90), but less well for zebrafish (r = 0.79). A non-invasive measure makes it possible to quickly assess brain size from a large number of individuals, as well as repeatedly measuring brain size of live individuals allowing calculation of brain growth. PMID:25279266

  11. The Influence of Genome and Cell Size on Brain Morphology in Amphibians.

    PubMed

    Roth, Gerhard; Walkowiak, Wolfgang

    2015-08-10

    In amphibians, nerve cell size is highly correlated with genome size, and increases in genome and cell size cause a retardation of the rate of development of nervous (as well as nonnervous) tissue leading to secondary simplification. This yields an inverse relationship between genome and cell size on the one hand and morphological complexity of the tectum mesencephali as the main visual center, the size of the torus semicircularis as the main auditory center, the size of the amphibian papilla as an important peripheral auditory structure, and the size of the cerebellum as a major sensorimotor center. Nervous structures developing later (e.g., torus and cerebellum) are more affected by secondary simplification than those that develop earlier (e.g., the tectum). This effect is more prominent in salamanders and caecilians than in frogs owing to larger genome and cells sizes in the former two taxa. We hypothesize that because of intragenomic evolutionary processes, important differences in brain morphology can arise independently of specific environmental selection.

  12. The Influence of Genome and Cell Size on Brain Morphology in Amphibians.

    PubMed

    Roth, Gerhard; Walkowiak, Wolfgang

    2015-09-01

    In amphibians, nerve cell size is highly correlated with genome size, and increases in genome and cell size cause a retardation of the rate of development of nervous (as well as nonnervous) tissue leading to secondary simplification. This yields an inverse relationship between genome and cell size on the one hand and morphological complexity of the tectum mesencephali as the main visual center, the size of the torus semicircularis as the main auditory center, the size of the amphibian papilla as an important peripheral auditory structure, and the size of the cerebellum as a major sensorimotor center. Nervous structures developing later (e.g., torus and cerebellum) are more affected by secondary simplification than those that develop earlier (e.g., the tectum). This effect is more prominent in salamanders and caecilians than in frogs owing to larger genome and cells sizes in the former two taxa. We hypothesize that because of intragenomic evolutionary processes, important differences in brain morphology can arise independently of specific environmental selection. PMID:26261281

  13. Brain Pathology in Adult Rats Treated With Domoic Acid.

    PubMed

    Vieira, A C; Alemañ, N; Cifuentes, J M; Bermúdez, R; Peña, M López; Botana, L M

    2015-11-01

    Domoic acid (DA) is a neurotoxin reported to produce damage to the hippocampus, which plays an important role in memory. The authors inoculated rats intraperitoneally with an effective toxic dose of DA to study the distribution of the toxin in major internal organs by using immunohistochemistry, as well as to evaluate the induced pathology by means of histopathologic and immunohistochemical methods at different time points after toxin administration (6, 10, and 24 hours; 5 and 54 days). DA was detected by immunohistochemistry exclusively in pyramidal neurons of the hippocampus at 6 and 10 hours after dosing. Lesions induced by DA were prominent at 5 days following treatment in selected regions of the brain: hippocampus, amygdala, piriform and perirhinal cortices, olfactory tubercle, septal nuclei, and thalamus. The authors found 2 types of lesions: delayed death of selective neurons and large areas of necrosis, both accompanied by astrocytosis and microgliosis. At 54 days after DA exposure, the pathology was characterized by still-distinguishable dying neurons, calcified lesions in the thalamus, persistent astrocytosis, and pronounced microgliosis. The expression of nitric oxide synthases suggests a role for nitric oxide in the pathogenesis of neuronal degeneration and chronic inflammation induced by DA in the brain.

  14. Analgesic use and the risk of primary adult brain tumor.

    PubMed

    Egan, Kathleen M; Nabors, Louis B; Thompson, Zachary J; Rozmeski, Carrie M; Anic, Gabriella A; Olson, Jeffrey J; LaRocca, Renato V; Chowdhary, Sajeel A; Forsyth, Peter A; Thompson, Reid C

    2016-09-01

    Glioma and meningioma are uncommon tumors of the brain with few known risk factors. Regular use of aspirin has been linked to a lower risk of gastrointestinal and other cancers, though evidence for an association with brain tumors is mixed. We examined the association of aspirin and other analgesics with the risk of glioma and meningioma in a large US case-control study. Cases were persons recently diagnosed with glioma or meningioma and treated at medical centers in the southeastern US. Controls were persons sampled from the same communities as the cases combined with friends and other associates of the cases. Information on past use of analgesics (aspirin, other anti-inflammatory agents, and acetaminophen) was collected in structured interviews. Logistic regression was used to estimate odds ratios (ORs) and 95 % confidence intervals (CIs) for analgesic use adjusted for potential confounders. All associations were considered according to indication for use. A total of 1123 glioma cases, 310 meningioma cases and 1296 controls were included in the analysis. For indications other than headache, glioma cases were less likely than controls to report regular use of aspirin (OR 0.69; CI 0.56, 0.87), in a dose-dependent manner (P trend < 0.001). No significant associations were observed with other analgesics for glioma, or any class of pain reliever for meningioma. Results suggest that regular aspirin use may reduce incidence of glioma. PMID:26894804

  15. Regional distribution of neuropeptide processing endopeptidases in adult rat brain.

    PubMed

    Berman, Y L; Rattan, A K; Carr, K; Devi, L

    1994-01-01

    Many peptide hormone and neuropeptide precursors undergo post-translational processing at mono- and/or dibasic residues. An enzymatic activity capable of processing prodynorphin at a monobasic processing site designated 'dynorphin converting enzyme' has been previously reported in rat rain and bovine pituitary. In this study the distribution of dynorphin converting enzyme activity in ten regions of rat brain has been compared with the distribution of subtilisin-like processing enzymes and with the immuno-reactive dynorphin peptides. The distribution of dynorphin converting enzyme activity generally matches the distribution of immuno-reactive dynorphin B-13 in most but not all brain regions. The regions that are known to have a relatively large number of immuno-reactive dynorphin-neurons also contain high levels of dynorphin converting enzyme activity. The distribution of dynorphin converting enzyme activity does not match the distribution of subtilisin-like processing enzyme or carboxypeptidase E activities. Taken together the data support the possibility that the dynorphin converting enzyme is involved in the maturation of dynorphin, as well as other neuropeptides, and peptide hormones.

  16. Rapid and efficient gene delivery into the adult mouse brain via focal electroporation

    PubMed Central

    Nomura, Tadashi; Nishimura, Yusuke; Gotoh, Hitoshi; Ono, Katsuhiko

    2016-01-01

    In vivo gene delivery is required for studying the cellular and molecular mechanisms of various biological events. Virus-mediated gene transfer or generation of transgenic animals is widely used; however, these methods are time-consuming and expensive. Here we show an improved electroporation technique for acute gene delivery into the adult mouse brain. Using a syringe-based microelectrode, local DNA injection and the application of electric current can be performed simultaneously; this allows rapid and efficient gene transduction of adult non-neuronal cells. Combining this technique with various expression vectors that carry specific promoters resulted in targeted gene expression in astrocytic cells. Our results constitute a powerful strategy for the genetic manipulation of adult brains in a spatio-temporally controlled manner. PMID:27430903

  17. Rapid and efficient gene delivery into the adult mouse brain via focal electroporation.

    PubMed

    Nomura, Tadashi; Nishimura, Yusuke; Gotoh, Hitoshi; Ono, Katsuhiko

    2016-01-01

    In vivo gene delivery is required for studying the cellular and molecular mechanisms of various biological events. Virus-mediated gene transfer or generation of transgenic animals is widely used; however, these methods are time-consuming and expensive. Here we show an improved electroporation technique for acute gene delivery into the adult mouse brain. Using a syringe-based microelectrode, local DNA injection and the application of electric current can be performed simultaneously; this allows rapid and efficient gene transduction of adult non-neuronal cells. Combining this technique with various expression vectors that carry specific promoters resulted in targeted gene expression in astrocytic cells. Our results constitute a powerful strategy for the genetic manipulation of adult brains in a spatio-temporally controlled manner. PMID:27430903

  18. Corpus callosum size and diffusion tensor anisotropy in adolescents and adults with schizophrenia.

    PubMed

    Balevich, Emily C; Haznedar, M Mehmet; Wang, Eugene; Newmark, Randall E; Bloom, Rachel; Schneiderman, Jason S; Aronowitz, Jonathan; Tang, Cheuk Y; Chu, King-Wai; Byne, William; Buchsbaum, Monte S; Hazlett, Erin A

    2015-03-30

    The corpus callosum has been implicated as a region of dysfunctional connectivity in schizophrenia, but the association between age and callosal pathology is unclear. Magnetic resonance imaging (MRI) and diffusion-tensor imaging (DTI) were performed on adults (n=34) and adolescents (n=17) with schizophrenia and adult (n=33) and adolescent (n=15) age- and sex-matched healthy controls. The corpus callosum was manually traced on each participant׳s MRI, and the DTI scan was co-registered to the MRI. The corpus callosum was divided into five anteroposterior segments. Area and anisotropy were calculated for each segment. Both patient groups demonstrated reduced callosal anisotropy; however, the adolescents exhibited reductions mostly in anterior regions while the reductions were more prominent in posterior regions of the adults. The adolescent patients showed greater decreases in absolute area as compared with the adult patients, particularly in the anterior segments. However, the adults showed greater reductions when area was considered relative to whole brain white matter volume. Our results suggest that the initial stages of the illness are characterized by deficiencies in frontal connections, and the chronic phase is characterized by deficits in the posterior corpus callosum; or, alternatively, adolescent-onset schizophrenia may represent a different or more severe form of the illness.

  19. Time and size at metamorphosis related to adult fitness in Ambystoma talpoideum

    SciTech Connect

    Semlitsch, R.D.; Scott, D.E.; Pechmann, J.H.K.

    1988-02-01

    The relationships among timing of metamorphosis, size at metamorphosis, and traits related to adult fitness were studied for 8 yr in the salamander Ambystoma talpoideum at a temporary pond. Among years, the modal time of metamorphosis and mean body size at metamorphosis were positively correlated with the date the pond dried. In years that the pond dried late, one group of larvae metamorphosed well before the pond dried, whereas the other group metamorphosed just before pond drying. Mean body size of late-metamorphosing individuals was not greater than that of individuals metamorphosing early. Early-metamorphosing males and females were larger at first and second reproduction than were late-metamorphosing individuals. Independent of timing of metamorphosis, larger juveniles at metamorphosis were also larger adults at first reproduction. Age at first reproduction for males was not associated with timing of or size at metamorphosis but large early-metamorphosing females reproduced at a younger age than did small early-metamorphosing females. Neither time of metamorphosis nor size at metamorphosis was associated with survival to first reproduction. These results demonstrate a direct relationship between phenotypic variation generated in the larval stage and adult traits closely associated with an individual's fitness.

  20. Superresolution Imaging of Aquaporin-4 Cluster Size in Antibody-Stained Paraffin Brain Sections.

    PubMed

    Smith, Alex J; Verkman, Alan S

    2015-12-15

    The water channel aquaporin-4 (AQP4) forms supramolecular clusters whose size is determined by the ratio of M1- and M23-AQP4 isoforms. In cultured astrocytes, differences in the subcellular localization and macromolecular interactions of small and large AQP4 clusters results in distinct physiological roles for M1- and M23-AQP4. Here, we developed quantitative superresolution optical imaging methodology to measure AQP4 cluster size in antibody-stained paraffin sections of mouse cerebral cortex and spinal cord, human postmortem brain, and glioma biopsy specimens. This methodology was used to demonstrate that large AQP4 clusters are formed in AQP4(-/-) astrocytes transfected with only M23-AQP4, but not in those expressing only M1-AQP4, both in vitro and in vivo. Native AQP4 in mouse cortex, where both isoforms are expressed, was enriched in astrocyte foot-processes adjacent to microcapillaries; clusters in perivascular regions of the cortex were larger than in parenchymal regions, demonstrating size-dependent subcellular segregation of AQP4 clusters. Two-color superresolution imaging demonstrated colocalization of Kir4.1 with AQP4 clusters in perivascular areas but not in parenchyma. Surprisingly, the subcellular distribution of AQP4 clusters was different between gray and white matter astrocytes in spinal cord, demonstrating regional specificity in cluster polarization. Changes in AQP4 subcellular distribution are associated with several neurological diseases and we demonstrate that AQP4 clustering was preserved in a postmortem human cortical brain tissue specimen, but that AQP4 was not substantially clustered in a human glioblastoma specimen despite high-level expression. Our results demonstrate the utility of superresolution optical imaging for measuring the size of AQP4 supramolecular clusters in paraffin sections of brain tissue and support AQP4 cluster size as a primary determinant of its subcellular distribution.

  1. Neuronal Organization of Deep Brain Opsin Photoreceptors in Adult Teleosts

    PubMed Central

    Hang, Chong Yee; Kitahashi, Takashi; Parhar, Ishwar S.

    2016-01-01

    Biological impacts of light beyond vision, i.e., non-visual functions of light, signify the need to better understand light detection (or photoreception) systems in vertebrates. Photopigments, which comprise light-absorbing chromophores bound to a variety of G-protein coupled receptor opsins, are responsible for visual and non-visual photoreception. Non-visual opsin photopigments in the retina of mammals and extra-retinal tissues of non-mammals play an important role in non-image-forming functions of light, e.g., biological rhythms and seasonal reproduction. This review highlights the role of opsin photoreceptors in the deep brain, which could involve conserved neurochemical systems that control different time- and light-dependent physiologies in in non-mammalian vertebrates including teleost fish. PMID:27199680

  2. Recovery trajectories after burn injury in young adults: does burn size matter?

    PubMed

    Ryan, Colleen M; Lee, Austin; Kazis, Lewis E; Schneider, Jeffrey C; Shapiro, Gabriel D; Sheridan, Robert L; Meyer, Walter J; Palmieri, Tina; Pidcock, Frank S; Reilly, Debra; Tompkins, Ronald G

    2015-01-01

    The impact of burn size on mortality is well known, but the association of burn size with the trajectories of long-term functional outcomes remains poorly studied. This prospective multi-center study included burned adults ages 19 to 30 years who completed the Young Adult Burn Outcome Questionnaire at initial baseline contact, 2 weeks, and at 6 and 12 months after initial questionnaire administration. Non-burned adults of comparable ages also completed the questionnaire as a reference group. The association between functional recovery and TBSA burned was analyzed longitudinally using generalized linear models with the generalized estimation equation technique. Functional status was characterized in 15 domains: physical function, fine motor function, pain, itch, social function limited by physical function, perceived appearance, social function limited by appearance, sexual function, emotion, family function, family concern, satisfaction with symptom relief, satisfaction with role, work reintegration, and religion. Scores were standardized to a mean of 50 and a SD of 10 based on non-burned controls. There were 153 burned and 112 non-burned subjects with a total of 620 questionnaires. TBSA burned was 11 ± 14% (mean ± SD); 31% had face involvement and 57% had hand involvement. The lag time from burn injury to questionnaire administration was on average 7 ± 7.7 months, with a maximum of 36 months. Lower recovery levels were associated with increasing burn size for physical function, pain, itch, work reintegration, emotion, satisfaction with symptom relief, satisfaction with role, family function, and family concern (P value ranged from .04-<.0001). No significant differences in recovery levels were found with increasing burn size for fine motor function, social function limited by physical function, sexual function, and religion; these areas tracked toward the age-matched non-burned group regardless of burn size. Perceived appearance and social function limited by

  3. Efficacy of 68Ga-DOTATOC Positron Emission Tomography (PET) CT in Children and Young Adults With Brain Tumors

    ClinicalTrials.gov

    2016-09-07

    Acoustic Schwannoma; Adult Anaplastic Astrocytoma; Adult Anaplastic Ependymoma; Adult Anaplastic Meningioma; Adult Anaplastic Oligodendroglioma; Adult Brain Stem Glioma; Adult Choroid Plexus Tumor; Adult Craniopharyngioma; Adult Diffuse Astrocytoma; Adult Ependymoblastoma; Adult Ependymoma; Adult Giant Cell Glioblastoma; Adult Glioblastoma; Adult Gliosarcoma; Adult Grade I Meningioma; Adult Grade II Meningioma; Adult Medulloblastoma; Adult Meningeal Hemangiopericytoma; Adult Mixed Glioma; Adult Myxopapillary Ependymoma; Adult Oligodendroglioma; Adult Papillary Meningioma; Adult Pilocytic Astrocytoma; Adult Pineal Gland Astrocytoma; Adult Pineoblastoma; Adult Pineocytoma; Adult Subependymal Giant Cell Astrocytoma; Adult Subependymoma; Adult Supratentorial Primitive Neuroectodermal Tumor (PNET); Childhood Choroid Plexus Tumor; Childhood Craniopharyngioma; Childhood Ependymoblastoma; Childhood Grade I Meningioma; Childhood Grade II Meningioma; Childhood Grade III Meningioma; Childhood High-grade Cerebellar Astrocytoma; Childhood High-grade Cerebral Astrocytoma; Childhood Infratentorial Ependymoma; Childhood Low-grade Cerebellar Astrocytoma; Childhood Low-grade Cerebral Astrocytoma; Childhood Medulloepithelioma; Childhood Supratentorial Ependymoma; Meningeal Melanocytoma; Newly Diagnosed Childhood Ependymoma; Recurrent Adult Brain Tumor; Recurrent Childhood Anaplastic Astrocytoma; Recurrent Childhood Anaplastic Oligoastrocytoma; Recurrent Childhood Anaplastic Oligodendroglioma; Recurrent Childhood Brain Stem Glioma; Recurrent Childhood Cerebellar Astrocytoma; Recurrent Childhood Cerebral Astrocytoma; Recurrent Childhood Diffuse Astrocytoma; Recurrent Childhood Ependymoma; Recurrent Childhood Fibrillary Astrocytoma; Recurrent Childhood Gemistocytic Astrocytoma; Recurrent Childhood Giant Cell Glioblastoma; Recurrent Childhood Glioblastoma; Recurrent Childhood Gliomatosis Cerebri; Recurrent Childhood Gliosarcoma; Recurrent Childhood Medulloblastoma; Recurrent Childhood

  4. Brain metabolite concentrations across cortical regions in healthy adults

    PubMed Central

    Bracken, Bethany K.; Jensen, J. Eric; Prescot, Andrew P.; Cohen, Bruce M.; Renshaw, Perry F.; Öngür, Dost

    2010-01-01

    Magnetic resonance spectroscopy (MRS) can provide in vivo information about metabolite levels across multiple brain regions. This study used MRS to examine concentrations of N-acetylaspartate (NAA), a marker of neuronal integrity and function, and choline (Cho) which is related to the amount of cell membrane per unit volume, in anterior cingulate cortex (ACC) and parieto-occipital cortex (POC) in healthy individuals. Data were drawn from two experiments which examined glutamatergic and GABAergic signaling in schizophrenia and bipolar disorder. After controlling for gray matter percentages, NAA/Creatine (Cr) was 18% higher in POC than in ACC (p<0.001); Cho/Cr was 46% lower in POC than in ACC (p<0.001). There was an effect of study (p<0.001 for both metabolites), but no region by study interaction (NAA p=0.101, Cho p=0.850). Since NAA is localized to the intracellular space, these data suggest that ACC neuronal compartment is reduced as compared with POC, or that there is a lower concentration of NAA per cell in the ACC than POC, or both. Since elevated Cho suggests more cell membrane per unit volume, reduced NAA in ACC appears to be coupled with increases in overall cell membrane compartment. These findings are consistent with a number of previous studies using proton MRS which found increasing NAA and decreasing Cho moving caudally, and with post mortem anatomical studies which found neurons in more widely spaced bundles in ACC when compared to parietal and occipital cortices. MRS may be a useful tool for studying physical properties of the living human brain. PMID:21081116

  5. Molecular and behavioral aspects of the actions of alcohol on the adult and developing brain.

    PubMed

    Alfonso-Loeches, Silvia; Guerri, Consuelo

    2011-01-01

    The brain is one of the major target organs of alcohol actions. Alcohol abuse can lead to alterations in brain structure and functions and, in some cases, to neurodegeneration. Cognitive deficits and alcohol dependence are highly damaging consequences of alcohol abuse. Clinical and experimental studies have demonstrated that the developing brain is particularly vulnerable to alcohol, and that drinking during gestation can lead to a range of physical, learning and behavioral defects (fetal alcohol spectrum disorders), with the most dramatic presentation corresponding to fetal alcohol syndrome. Recent findings also indicate that adolescence is a stage of brain maturation and that heavy drinking at this stage can have a negative impact on brain structure and functions causing important short- and long-term cognitive and behavioral consequences. The effects of alcohol on the brain are not uniform; some brain areas or cell populations are more vulnerable than others. The prefrontal cortex, the hippocampus, the cerebellum, the white matter and glial cells are particularly susceptible to the effects of ethanol. The molecular actions of alcohol on the brain are complex and involve numerous mechanisms and signaling pathways. Some of the mechanisms involved are common for the adult brain and for the developing brain, while others depend on the developmental stage. During brain ontogeny, alcohol causes irreversible alterations to the brain structure. It also impairs several molecular, neurochemical and cellular events taking place during normal brain development, including alterations in both gene expression regulation and the molecules involved in cell-cell interactions, interference with the mitogenic and growth factor response, enhancement of free radical formation and derangements of glial cell functions. However, in both adult and adolescent brains, alcohol damages specific brain areas through mechanisms involving excitotoxicity, free radical formation and

  6. Homeostasis of Microglia in the Adult Brain: Review of Novel Microglia Depletion Systems.

    PubMed

    Waisman, Ari; Ginhoux, Florent; Greter, Melanie; Bruttger, Julia

    2015-10-01

    Microglia are brain macrophages that emerge from early erythro-myeloid precursors in the embryonic yolk sac and migrate to the brain mesenchyme before the blood brain barrier is formed. They seed the brain, and proliferate until they have formed a grid-like distribution in the central nervous system that is maintained throughout lifespan. The mechanisms through which these embryonic-derived cells contribute to microglia homoeostasis at steady state and upon inflammation are still not entirely clear. Here we review recent studies that provided insight into the contribution of embryonically-derived microglia and of adult 'microglia-like' cells derived from monocytes during inflammation. We examine different microglia depletion models, and discuss the origin of their rapid repopulation after depletion and outline important areas of future research.

  7. The needs of aging parents caring for an adult with acquired brain injury.

    PubMed

    Minnes, Patricia; Woodford, Lynn; Carlson, Peter; Johnston, Jane; McColl, Mary Ann

    2010-06-01

    This study focused on issues of concern to and service needs of older parents caring for an adult son or daughter with an acquired brain injury (ABI) in Ontario. Three issues were identified as particularly challenging: diagnosis of the brain injury, parents' feelings about the cause of the brain injury, and planning for long-term accommodation for their family member with a brain injury. The most frequently cited services needed for the person with ABI were social and/or recreational activities, day programs, and residential placement. The most frequently cited services needed by parents were parent education and support groups. The information gathered provides a base for further research in other sectors. Implications of these initial findings for clinical practice and policy and program development are discussed.

  8. Analysis of chaperone mRNA expression in the adult mouse brain by meta analysis of the Allen Brain Atlas.

    PubMed

    Tebbenkamp, Andrew T N; Borchelt, David R

    2010-10-28

    The pathology of many neurodegenerative diseases is characterized by the accumulation of misfolded and aggregated proteins in various cell types and regional substructures throughout the central and peripheral nervous systems. The accumulation of these aggregated proteins signals dysfunction of cellular protein homeostatic mechanisms such as the ubiquitin/proteasome system, autophagy, and the chaperone network. Although there are several published studies in which transcriptional profiling has been used to examine gene expression in various tissues, including tissues of neurodegenerative disease models, there has not been a report that focuses exclusively on expression of the chaperone network. In the present study, we used the Allen Brain Atlas online database to analyze chaperone expression levels. This database utilizes a quantitative in situ hybridization approach and provides data on 270 chaperone genes within many substructures of the adult mouse brain. We determined that 256 of these chaperone genes are expressed at some level. Surprisingly, relatively few genes, only 30, showed significant variations in levels of mRNA across different substructures of the brain. The greatest degree of variability was exhibited by genes of the DnaJ co-chaperone, Tetratricopeptide repeat, and the HSPH families. Our analysis provides a valuable resource towards determining how variations in chaperone gene expression may modulate the vulnerability of specific neuronal populations of mammalian brain.

  9. Evaluation of a Reading Comprehension Strategy Package to Improve Reading Comprehension of Adult College Students with Acquired Brain Injuries

    ERIC Educational Resources Information Center

    Griffiths, Gina G.

    2013-01-01

    Adults with mild to moderate acquired brain injury (ABI) often pursue post-secondary or professional education after their injuries in order to enter or re-enter the job market. An increasing number of these adults report problems with reading-to-learn. The problem is particularly concerning given the growing population of adult survivors of ABI.…

  10. Frog Virus 3 dissemination in the brain of tadpoles, but not in adult Xenopus, involves blood brain barrier dysfunction

    PubMed Central

    De Jesús Andino, Francisco; Jones, Letitia; Maggirwar, Sanjay B.; Robert, Jacques

    2016-01-01

    While increasing evidence points to a key role of monocytes in amphibian host defenses, monocytes are also thought to be important in the dissemination and persistent infection caused by ranavirus. However, little is known about the fate of infected macrophages or if ranavirus exploits immune privileged organs, such as the brain, in order to establish a reservoir. The amphibian Xenopus laevis and Frog Virus 3 (FV3) were established as an experimental platform for investigating in vivo whether ranavirus could disseminate to the brain. Our data show that the FV3 infection alters the BBB integrity, possibly mediated by an inflammatory response, which leads to viral dissemination into the central nervous system in X. laevis tadpole but not adult. Furthermore, our data suggest that the macrophages play a major role in viral dissemination by carrying the virus into the neural tissues. PMID:26931458

  11. Population variation in brain size of nine-spined sticklebacks (Pungitius pungitius) - local adaptation or environmentally induced variation?

    PubMed Central

    2011-01-01

    Background Most evolutionary studies on the size of brains and different parts of the brain have relied on interspecific comparisons, and have uncovered correlations between brain architecture and various ecological, behavioural and life-history traits. Yet, similar intraspecific studies are rare, despite the fact that they could better determine how selection and phenotypic plasticity influence brain architecture. We investigated the variation in brain size and structure in wild-caught nine-spined sticklebacks (Pungitius pungitius) from eight populations, representing marine, lake, and pond habitats, and compared them to data from a previous common garden study from a smaller number of populations. Results Brain size scaled hypo-allometrically with body size, irrespective of population origin, with a common slope of 0.5. Both absolute and relative brain size, as well as relative telencephalon, optic tectum and cerebellum size, differed significantly among the populations. Further, absolute and relative brain sizes were larger in pond than in marine populations, while the telencephalon tended to be larger in marine than in pond populations. These findings are partly incongruent with previous common garden results. A direct comparison between wild and common garden fish from the same populations revealed a habitat-specific effect: pond fish had relatively smaller brains in a controlled environment than in the wild, while marine fish were similar. All brain parts were smaller in the laboratory than in the wild, irrespective of population origin. Conclusion Our results indicate that variation among populations is large, both in terms of brain size and in the size of separate brain parts in wild nine-spined sticklebacks. However, the incongruence between the wild and common garden patterns suggests that much of the population variation found in the wild may be attributable to environmentally induced phenotypic plasticity. Given that the brain is among the most plastic

  12. Relation of adult size to movements and distribution of smallmouth bass in a central Maine Lake

    USGS Publications Warehouse

    Cole, M.B.; Moring, J.R.

    1997-01-01

    Forty-four smallmouth bass Micropterus dolomieu of three size-classes were radiotracked in Green Lake, Maine, during summer 1993 (10 June-1 September) to determine whether adult size influenced distribution and movement. Large smallmouth bass (>406 mm) used deep water (>8 m) more often than did small (248-279 mm) or medium-sized (305-356 mm) smallmouth bass during the late summer (15 July-1 September). Large smallmouth bass also were found at middepths (4-8 m) significantly more often than were small individuals during late summer. Small fish used cover more frequently than large ones during early summer (10 June-13 July). Both small and medium-sized individuals were associated with cover more frequently than large smallmouth bass were during the late summer. Small smallmouth bass exhibited significantly smaller summer total ranges than did large individuals, and mean active displacement differed among all three size-classes.

  13. Impact of spot size on plan quality of spot scanning proton radiosurgery for peripheral brain lesions

    SciTech Connect

    Wang, Dongxu Dirksen, Blake; Hyer, Daniel E.; Buatti, John M.; Sheybani, Arshin; Dinges, Eric; Felderman, Nicole; TenNapel, Mindi; Bayouth, John E.; Flynn, Ryan T.

    2014-12-15

    Purpose: To determine the plan quality of proton spot scanning (SS) radiosurgery as a function of spot size (in-air sigma) in comparison to x-ray radiosurgery for treating peripheral brain lesions. Methods: Single-field optimized (SFO) proton SS plans with sigma ranging from 1 to 8 mm, cone-based x-ray radiosurgery (Cone), and x-ray volumetric modulated arc therapy (VMAT) plans were generated for 11 patients. Plans were evaluated using secondary cancer risk and brain necrosis normal tissue complication probability (NTCP). Results: For all patients, secondary cancer is a negligible risk compared to brain necrosis NTCP. Secondary cancer risk was lower in proton SS plans than in photon plans regardless of spot size (p = 0.001). Brain necrosis NTCP increased monotonically from an average of 2.34/100 (range 0.42/100–4.49/100) to 6.05/100 (range 1.38/100–11.6/100) as sigma increased from 1 to 8 mm, compared to the average of 6.01/100 (range 0.82/100–11.5/100) for Cone and 5.22/100 (range 1.37/100–8.00/100) for VMAT. An in-air sigma less than 4.3 mm was required for proton SS plans to reduce NTCP over photon techniques for the cohort of patients studied with statistical significance (p = 0.0186). Proton SS plans with in-air sigma larger than 7.1 mm had significantly greater brain necrosis NTCP than photon techniques (p = 0.0322). Conclusions: For treating peripheral brain lesions—where proton therapy would be expected to have the greatest depth-dose advantage over photon therapy—the lateral penumbra strongly impacts the SS plan quality relative to photon techniques: proton beamlet sigma at patient surface must be small (<7.1 mm for three-beam single-field optimized SS plans) in order to achieve comparable or smaller brain necrosis NTCP relative to photon radiosurgery techniques. Achieving such small in-air sigma values at low energy (<70 MeV) is a major technological challenge in commercially available proton therapy systems.

  14. The functional organisation of glia in the adult brain of Drosophila and other insects

    PubMed Central

    Edwards, Tara N.; Meinertzhagen, Ian A.

    2010-01-01

    This review annotates and categorises the glia of adult Drosophila and other model insects and describes the developmental origins of these in the Drosophila optic lobe. The functions of glia in the adult vary depending upon their sub-type and location in the brain. The task of annotating glia is essentially complete only for the glia of the fly's lamina, which comprise: two types of surface glia - the pseudocartridge and fenestrated glia; two types of cortex glia - the distal and proximal satellite glia; and two types of neuropile glia - the epithelial and marginal glia. We advocate that the term subretinal glia, as used to refer to both pseudocartridge and fenestrated glia, be abandoned. Other neuropiles contain similar glial subtypes, but other than the antennal lobes these have not been described in detail. Surface glia form the blood brain barrier, regulating the flow of substances into and out of the nervous system, both for the brain as a whole and the optic neuropiles in particular. Cortex glia provide a second level of barrier, wrapping axon fascicles and isolating neuronal cell bodies both from neighbouring brain regions and from their underlying neuropiles. Neuropile glia can be generated in the adult and a subtype, ensheathing glia, are responsible for cleaning up cellular debris during Wallerian degeneration. Both the neuropile ensheathing and astrocyte-like glia may be involved in clearing neurotransmitters from the extracellular space, thus modifying the levels of histamine, glutamate and possibly dopamine at the synapse to ultimately affect behaviour. PMID:20109517

  15. The lifecycle effects of nutrition and body size on adult adiposity, diabetes and cardiovascular disease.

    PubMed

    Yajnik, C S

    2002-08-01

    This study was undertaken to review the links between maternal nutrition, offspring's birth weight and the propensity to early insulin resistance and high diabetes rates in Indian adults. Studies included a comparison of maternal size and nutrition with birth weights in Pune, India, and Southampton, UK. In Pune, the growth, insulin resistance and blood pressure of four-year-old children were assessed. Adults >40 years of age, who were resident in rural areas, were compared with adults living in urban areas for size, glucose handling, lipid status and blood pressure. Newly diagnosed diabetic adults living in urban areas were also monitored. Height, weight, head, waist and hip circumferences, skin-fold measurements and blood pressure were routinely measured. Fasting glucose, insulin, total and high-density lipoprotein cholesterol and triglycerides were linked to the glucose and insulin responses during glucose tolerance tests. Cytokine levels were measured in plasma samples of urban and rural adults. Indian babies were lighter, thinner, shorter and had a relatively lower lean tissue mass than the Caucasian babies. However, the subcutaneous fat measurements of these babies were comparable to those of the white Caucasian babies. The Indian mothers were small, but relatively fat mothers produced larger babies. Maternal intake of green vegetables, fruit and milk, and their circulating folate and vitamin C levels, predicted larger fetal size. Rapid childhood growth promoted insulin resistance and higher blood pressure. Rural adults were thin, with a 4% prevalence of diabetes and a 14% prevalence of hypertension, but the risks increased within the normal body mass index (BMI) range. Type 2 diabetes was common in urban adults younger than 35 years of age. Although the average BMI was 23.9 kg m(-2), central obesity and thin limbs were noteworthy. Levels of interleukin-6 and tumour necrosis factor-a were markedly increased in urban dwellers. Hence, there is evidence of a

  16. The lifecycle effects of nutrition and body size on adult adiposity, diabetes and cardiovascular disease.

    PubMed

    Yajnik, C S

    2002-08-01

    This study was undertaken to review the links between maternal nutrition, offspring's birth weight and the propensity to early insulin resistance and high diabetes rates in Indian adults. Studies included a comparison of maternal size and nutrition with birth weights in Pune, India, and Southampton, UK. In Pune, the growth, insulin resistance and blood pressure of four-year-old children were assessed. Adults >40 years of age, who were resident in rural areas, were compared with adults living in urban areas for size, glucose handling, lipid status and blood pressure. Newly diagnosed diabetic adults living in urban areas were also monitored. Height, weight, head, waist and hip circumferences, skin-fold measurements and blood pressure were routinely measured. Fasting glucose, insulin, total and high-density lipoprotein cholesterol and triglycerides were linked to the glucose and insulin responses during glucose tolerance tests. Cytokine levels were measured in plasma samples of urban and rural adults. Indian babies were lighter, thinner, shorter and had a relatively lower lean tissue mass than the Caucasian babies. However, the subcutaneous fat measurements of these babies were comparable to those of the white Caucasian babies. The Indian mothers were small, but relatively fat mothers produced larger babies. Maternal intake of green vegetables, fruit and milk, and their circulating folate and vitamin C levels, predicted larger fetal size. Rapid childhood growth promoted insulin resistance and higher blood pressure. Rural adults were thin, with a 4% prevalence of diabetes and a 14% prevalence of hypertension, but the risks increased within the normal body mass index (BMI) range. Type 2 diabetes was common in urban adults younger than 35 years of age. Although the average BMI was 23.9 kg m(-2), central obesity and thin limbs were noteworthy. Levels of interleukin-6 and tumour necrosis factor-a were markedly increased in urban dwellers. Hence, there is evidence of a

  17. Restraint Stress-Induced Morphological Changes at the Blood-Brain Barrier in Adult Rats

    PubMed Central

    Sántha, Petra; Veszelka, Szilvia; Hoyk, Zsófia; Mészáros, Mária; Walter, Fruzsina R.; Tóth, Andrea E.; Kiss, Lóránd; Kincses, András; Oláh, Zita; Seprényi, György; Rákhely, Gábor; Dér, András; Pákáski, Magdolna; Kálmán, János; Kittel, Ágnes; Deli, Mária A.

    2016-01-01

    Stress is well-known to contribute to the development of both neurological and psychiatric diseases. While the role of the blood-brain barrier is increasingly recognized in the development of neurodegenerative disorders, such as Alzheimer's disease, dysfunction of the blood-brain barrier has been linked to stress-related psychiatric diseases only recently. In the present study the effects of restraint stress with different duration (1, 3, and 21 days) were investigated on the morphology of the blood-brain barrier in male adult Wistar rats. Frontal cortex and hippocampus sections were immunostained for markers of brain endothelial cells (claudin-5, occluding, and glucose transporter-1) and astroglia (GFAP). Staining pattern and intensity were visualized by confocal microscopy and evaluated by several types of image analysis. The ultrastructure of brain capillaries was investigated by electron microscopy. Morphological changes and intensity alterations in brain endothelial tight junction proteins claudin-5 and occludin were induced by stress. Following restraint stress significant increases in the fluorescence intensity of glucose transporter-1 were detected in brain endothelial cells in the frontal cortex and hippocampus. Significant reductions in GFAP fluorescence intensity were observed in the frontal cortex in all stress groups. As observed by electron microscopy, 1-day acute stress induced morphological changes indicating damage in capillary endothelial cells in both brain regions. After 21 days of stress thicker and irregular capillary basal membranes in the hippocampus and edema in astrocytes in both regions were seen. These findings indicate that stress exerts time-dependent changes in the staining pattern of tight junction proteins occludin, claudin-5, and glucose transporter-1 at the level of brain capillaries and in the ultrastructure of brain endothelial cells and astroglial endfeet, which may contribute to neurodegenerative processes, cognitive and

  18. Restraint Stress-Induced Morphological Changes at the Blood-Brain Barrier in Adult Rats.

    PubMed

    Sántha, Petra; Veszelka, Szilvia; Hoyk, Zsófia; Mészáros, Mária; Walter, Fruzsina R; Tóth, Andrea E; Kiss, Lóránd; Kincses, András; Oláh, Zita; Seprényi, György; Rákhely, Gábor; Dér, András; Pákáski, Magdolna; Kálmán, János; Kittel, Ágnes; Deli, Mária A

    2015-01-01

    Stress is well-known to contribute to the development of both neurological and psychiatric diseases. While the role of the blood-brain barrier is increasingly recognized in the development of neurodegenerative disorders, such as Alzheimer's disease, dysfunction of the blood-brain barrier has been linked to stress-related psychiatric diseases only recently. In the present study the effects of restraint stress with different duration (1, 3, and 21 days) were investigated on the morphology of the blood-brain barrier in male adult Wistar rats. Frontal cortex and hippocampus sections were immunostained for markers of brain endothelial cells (claudin-5, occluding, and glucose transporter-1) and astroglia (GFAP). Staining pattern and intensity were visualized by confocal microscopy and evaluated by several types of image analysis. The ultrastructure of brain capillaries was investigated by electron microscopy. Morphological changes and intensity alterations in brain endothelial tight junction proteins claudin-5 and occludin were induced by stress. Following restraint stress significant increases in the fluorescence intensity of glucose transporter-1 were detected in brain endothelial cells in the frontal cortex and hippocampus. Significant reductions in GFAP fluorescence intensity were observed in the frontal cortex in all stress groups. As observed by electron microscopy, 1-day acute stress induced morphological changes indicating damage in capillary endothelial cells in both brain regions. After 21 days of stress thicker and irregular capillary basal membranes in the hippocampus and edema in astrocytes in both regions were seen. These findings indicate that stress exerts time-dependent changes in the staining pattern of tight junction proteins occludin, claudin-5, and glucose transporter-1 at the level of brain capillaries and in the ultrastructure of brain endothelial cells and astroglial endfeet, which may contribute to neurodegenerative processes, cognitive and

  19. Light scattering properties vary across different regions of the adult mouse brain.

    PubMed

    Al-Juboori, Saif I; Dondzillo, Anna; Stubblefield, Elizabeth A; Felsen, Gidon; Lei, Tim C; Klug, Achim

    2013-01-01

    Recently developed optogenetic tools provide powerful approaches to optically excite or inhibit neural activity. In a typical in-vivo experiment, light is delivered to deep nuclei via an implanted optical fiber. Light intensity attenuates with increasing distance from the fiber tip, determining the volume of tissue in which optogenetic proteins can successfully be activated. However, whether and how this volume of effective light intensity varies as a function of brain region or wavelength has not been systematically studied. The goal of this study was to measure and compare how light scatters in different areas of the mouse brain. We delivered different wavelengths of light via optical fibers to acute slices of mouse brainstem, midbrain and forebrain tissue. We measured light intensity as a function of distance from the fiber tip, and used the data to model the spread of light in specific regions of the mouse brain. We found substantial differences in effective attenuation coefficients among different brain areas, which lead to substantial differences in light intensity demands for optogenetic experiments. The use of light of different wavelengths additionally changes how light illuminates a given brain area. We created a brain atlas of effective attenuation coefficients of the adult mouse brain, and integrated our data into an application that can be used to estimate light scattering as well as required light intensity for optogenetic manipulation within a given volume of tissue.

  20. Light Scattering Properties Vary across Different Regions of the Adult Mouse Brain

    PubMed Central

    Stubblefield, Elizabeth A.; Felsen, Gidon

    2013-01-01

    Recently developed optogenetic tools provide powerful approaches to optically excite or inhibit neural activity. In a typical in-vivo experiment, light is delivered to deep nuclei via an implanted optical fiber. Light intensity attenuates with increasing distance from the fiber tip, determining the volume of tissue in which optogenetic proteins can successfully be activated. However, whether and how this volume of effective light intensity varies as a function of brain region or wavelength has not been systematically studied. The goal of this study was to measure and compare how light scatters in different areas of the mouse brain. We delivered different wavelengths of light via optical fibers to acute slices of mouse brainstem, midbrain and forebrain tissue. We measured light intensity as a function of distance from the fiber tip, and used the data to model the spread of light in specific regions of the mouse brain. We found substantial differences in effective attenuation coefficients among different brain areas, which lead to substantial differences in light intensity demands for optogenetic experiments. The use of light of different wavelengths additionally changes how light illuminates a given brain area. We created a brain atlas of effective attenuation coefficients of the adult mouse brain, and integrated our data into an application that can be used to estimate light scattering as well as required light intensity for optogenetic manipulation within a given volume of tissue. PMID:23874433

  1. Prenatal exposure to permethrin influences vascular development of fetal brain and adult behavior in mice offspring.

    PubMed

    Imanishi, Satoshi; Okura, Masahiro; Zaha, Hiroko; Yamamoto, Toshifumi; Akanuma, Hiromi; Nagano, Reiko; Shiraishi, Hiroaki; Fujimaki, Hidekazu; Sone, Hideko

    2013-11-01

    Pyrethroids are one of the most widely used classes of insecticides and show neurotoxic effects that induce oxidative stress in the neonatal rat brain. However, little is still known about effects of prenatal exposure to permethrin on vascular development in fetal brain, central nervous system development, and adult offspring behaviors. In this study, the effects of prenatal exposure to permethrin on the development of cerebral arteries in fetal brains, neurotransmitter in neonatal brains, and locomotor activities in offspring mice were investigated. Permethrin (0, 2, 10, 50, and 75 mg/kg) was orally administered to pregnant females once on gestation day 10.5. The brains of permethrin-treated fetuses showed altered vascular formation involving shortened lengths of vessels, an increased number of small branches, and, in some cases, insufficient fusion of the anterior communicating arteries in the area of circle of Willis. The prenatal exposure to permethrin altered neocortical and hippocampus thickness in the mid brain and significantly increased norepinephrine and dopamine levels at postnatal day 7 mice. For spontaneous behavior, the standing ability test using a viewing jar and open-field tests showed significant decrease of the standing ability and locomotor activity in male mice at 8 or 12 weeks of age, respectively. The results suggest that prenatal exposure to permethrin may affect insufficient development of the brain through alterations of vascular development.

  2. Light scattering properties vary across different regions of the adult mouse brain

    NASA Astrophysics Data System (ADS)

    Al-Juboori, Saif I.

    Recently developed optogenetic tools provide powerful approaches to optically excite or inhibit neural activity. In a typical in-vivo experiment, light is delivered to deep nuclei via an implanted optical fiber. Light intensity attenuates with increasing distance from the fiber tip, determining the volume of tissue in which optogenetic proteins can successfully be activated. However, whether and how this volume of effective light intensity varies as a function of brain region or wavelength has not been systematically studied. The goal of this study was to measure and compare how light scatters in different areas of the mouse brain. We delivered different wavelengths of light via optical fibers to acute slices of mouse brainstem, midbrain and forebrain tissue. We measured light intensity as a function of distance from the fiber tip, and used the data to model the spread of light in specific regions of the mouse brain. We found substantial differences in effective attenuation coefficients among different brain areas, which lead to substantial differences in light intensity demands for optogenetic experiments. The use of light of different wavelengths additionally changes how light illuminates a given brain area. We created a brain atlas of effective attenuation coefficients of the adult mouse brain, and integrated our data into an application that can be used to estimate light scattering as well as required light intensity for optogenetic manipulation within a given volume of tissue.

  3. MAPK signaling determines anxiety in the juvenile mouse brain but depression-like behavior in adults.

    PubMed

    Wefers, Benedikt; Hitz, Christiane; Hölter, Sabine M; Trümbach, Dietrich; Hansen, Jens; Weber, Peter; Pütz, Benno; Deussing, Jan M; de Angelis, Martin Hrabé; Roenneberg, Till; Zheng, Fang; Alzheimer, Christian; Silva, Alcino; Wurst, Wolfgang; Kühn, Ralf

    2012-01-01

    MAP kinase signaling has been implicated in brain development, long-term memory, and the response to antidepressants. Inducible Braf knockout mice, which exhibit protein depletion in principle forebrain neurons, enabled us to unravel a new role of neuronal MAPK signaling for emotional behavior. Braf mice that were induced during adulthood showed normal anxiety but increased depression-like behavior, in accordance with pharmacological findings. In contrast, the inducible or constitutive inactivation of Braf in the juvenile brain leads to normal depression-like behavior but decreased anxiety in adults. In juvenile, constitutive mutants we found no alteration of GABAergic neurotransmission but reduced neuronal arborization in the dentate gyrus. Analysis of gene expression in the hippocampus revealed nine downregulated MAPK target genes that represent candidates to cause the mutant phenotype.Our results reveal the differential function of MAPK signaling in juvenile and adult life phases and emphasize the early postnatal period as critical for the determination of anxiety in adults. Moreover, these results validate inducible gene inactivation as a new valuable approach, allowing it to discriminate between gene function in the adult and the developing postnatal brain. PMID:22529971

  4. Area-specific migration and recruitment of new neurons in the adult songbird brain.

    PubMed

    Vellema, Michiel; van der Linden, Annemie; Gahr, Manfred

    2010-05-01

    Neuron recruitment has been implicated in morphological and functional plasticity in the adult brain. Whereas mammals restrict neuron recruitment specifically to two regions of known plasticity, the hippocampus and olfactory bulb, newborn neurons are found throughout the forebrain of adult songbirds. In order to study the area-specificity of the widespread proliferation and recruitment in the songbird brain, six adult male canaries received repetitive intraperitoneal injections of the mitotic marker BrdU (5-bromo-2-deoxyuridine) and were sacrificed after 24 hours to study proliferation or after 38 days to study recruitment. Migration and incorporation of new neurons was apparent throughout many but not all parts of the canary forebrain and was quantitatively related to mitotic levels in the most closely associated proliferative zones. Surprisingly, some areas of the vocal control system sensitive to plastic changes, such as nucleus higher vocal center (HVC) and area X, recruited similar numbers of new neurons as their surrounding brain tissues, employing no specific directional mechanisms. The distribution pattern in and around HVC could best be described by a random displacement model, where cells originating from the overlying lateral ventricle can move independently in any direction. Other plastic song control areas, such as the medial magnocellular nucleus of anterior nidopallium and the robust nucleus of arcopallium, were specifically avoided by migrating neurons, while migration toward the olfactory bulb showed high specificity, similar to the mammalian rostral migratory stream. Thus, different mechanisms appear to organize area-specific neuron recruitment in different recipients of the adult songbird brain, unrelated to global plasticity of brain regions.

  5. Diphyllobothrium nihonkaiense: wide egg size variation in 32 molecularly confirmed adult specimens from Korea.

    PubMed

    Choi, Seoyun; Cho, Jaeeun; Jung, Bong-Kwang; Kim, Deok-Gyu; Jeon, Sarah Jiyoun; Jeon, Hyeong-Kyu; Eom, Keeseon S; Chai, Jong-Yil

    2015-06-01

    The eggs of Diphyllobothrium nihonkaiense were reported to be smaller than those of the classical Diphyllobothrium latum in general. However, verification using a large number of adult tapeworms is required. We assessed the egg size variation in 32 adult specimens of D. nihonkaiense recovered from Korean patients in 1975-2014. The diagnosis of individual specimens was based on analysis of the mitochondrial cytochrome c oxidase 1 gene sequence. Uterine eggs (n = 10) were obtained from each specimen, and their length and width were measured by micrometry. The results indicated that the egg size of D. nihonkaiense (total number of eggs measured, 320) was widely variable according to individual specimens, 54-76 μm long (mean 64) and 35-58 μm wide (mean 45), with a length-width ratio of 1.32-1.70 (mean 1.46). The worm showing the smallest egg size had a length range of 54-62 μm, whereas the one showing the largest egg size had a length range of 68-76 μm. The two ranges did not overlap, and a similar pattern was observed for the egg width. Mapping of each egg size (n = 320) showed a wide variation in length and width. The widely variable egg size of D. nihonkaiense cannot be used for specific diagnosis of diphyllobothriid tapeworm infections in human patients.

  6. Colony size selection determines adult survival and dispersal preferences: allee effects in a colonial bird.

    PubMed

    Serrano, David; Oro, Daniel; Ursua, Esperanza; Tella, José L

    2005-08-01

    Avian coloniality traditionally has been investigated by examining how breeding success varies with colony size, but other crucial fitness components rarely have been examined. This may lead to wrong conclusions because unmeasured parameters may change the final fitness balance. We used multistate capture-recapture models to investigate adult survival and dispersal in relation to colony size within a long-term monitored population of lesser kestrels (Falco naumanni). Nest predation probability decreases with colony size, and adult survival is predicted to show the same trend because adults are exposed to the same suite of predators. As expected, survival probability was higher in large colonies (0.72+/-0.015; mean+/-SE) than in medium or small colonies (0.65+/-0.02). Additionally, dispersal probabilities were higher going from small to large colonies (0.20+/-0.01) than from large to small (0.08+/-0.01), as predicted by theory of habitat selection shaped by fitness maximization. These asymmetries are likely to generate size-specific colony population dynamics, so they should be taken into account in studies of colonial birds and other metapopulation-like systems. Allee effects, that is, positive density dependence, appear to be the cause of the evolution of dispersal behavior and may explain the maintenance of coloniality in this species. PMID:16032568

  7. Mammalian collection on Noah's Ark: the effects of beauty, brain and body size.

    PubMed

    Frynta, Daniel; Šimková, Olga; Lišková, Silvie; Landová, Eva

    2013-01-01

    The importance of today's zoological gardens as the so-called "Noah's Ark" grows as the natural habitat of many species quickly diminishes. Their potential to shelter a large amount of individuals from many species gives us the opportunity to reintroduce a species that disappeared in nature. However, the selection of animals to be kept in zoos worldwide is highly selective and depends on human decisions driven by both ecological criteria such as population size or vulnerability and audience-driven criteria such as aesthetic preferences. Thus we focused our study on the most commonly kept and bred animal class, the mammals, and we asked which factors affect various aspects of the mammalian collection of zoos. We analyzed the presence/absence, population size, and frequency per species of each of the 123 mammalian families kept in the worldwide zoo collection. Our aim was to explain these data using the human-perceived attractiveness of mammalian families, their body weight, relative brain size and species richness of the family. In agreement with various previous studies, we found that the body size and the attractiveness of mammals significantly affect all studied components of the mammalian collection of zoos. There is a higher probability of the large and attractive families to be kept. Once kept, these animals are presented in larger numbers in more zoos. On the contrary, the relative mean brain size only affects the primary selection whether to keep the family or not. It does not affect the zoo population size or the number of zoos that keep the family. PMID:23690985

  8. Mammalian collection on Noah's Ark: the effects of beauty, brain and body size.

    PubMed

    Frynta, Daniel; Šimková, Olga; Lišková, Silvie; Landová, Eva

    2013-01-01

    The importance of today's zoological gardens as the so-called "Noah's Ark" grows as the natural habitat of many species quickly diminishes. Their potential to shelter a large amount of individuals from many species gives us the opportunity to reintroduce a species that disappeared in nature. However, the selection of animals to be kept in zoos worldwide is highly selective and depends on human decisions driven by both ecological criteria such as population size or vulnerability and audience-driven criteria such as aesthetic preferences. Thus we focused our study on the most commonly kept and bred animal class, the mammals, and we asked which factors affect various aspects of the mammalian collection of zoos. We analyzed the presence/absence, population size, and frequency per species of each of the 123 mammalian families kept in the worldwide zoo collection. Our aim was to explain these data using the human-perceived attractiveness of mammalian families, their body weight, relative brain size and species richness of the family. In agreement with various previous studies, we found that the body size and the attractiveness of mammals significantly affect all studied components of the mammalian collection of zoos. There is a higher probability of the large and attractive families to be kept. Once kept, these animals are presented in larger numbers in more zoos. On the contrary, the relative mean brain size only affects the primary selection whether to keep the family or not. It does not affect the zoo population size or the number of zoos that keep the family.

  9. Mammalian Collection on Noah's Ark: The Effects of Beauty, Brain and Body Size

    PubMed Central

    Frynta, Daniel; Šimková, Olga; Lišková, Silvie; Landová, Eva

    2013-01-01

    The importance of today's zoological gardens as the so-called “Noah's Ark” grows as the natural habitat of many species quickly diminishes. Their potential to shelter a large amount of individuals from many species gives us the opportunity to reintroduce a species that disappeared in nature. However, the selection of animals to be kept in zoos worldwide is highly selective and depends on human decisions driven by both ecological criteria such as population size or vulnerability and audience-driven criteria such as aesthetic preferences. Thus we focused our study on the most commonly kept and bred animal class, the mammals, and we asked which factors affect various aspects of the mammalian collection of zoos. We analyzed the presence/absence, population size, and frequency per species of each of the 123 mammalian families kept in the worldwide zoo collection. Our aim was to explain these data using the human-perceived attractiveness of mammalian families, their body weight, relative brain size and species richness of the family. In agreement with various previous studies, we found that the body size and the attractiveness of mammals significantly affect all studied components of the mammalian collection of zoos. There is a higher probability of the large and attractive families to be kept. Once kept, these animals are presented in larger numbers in more zoos. On the contrary, the relative mean brain size only affects the primary selection whether to keep the family or not. It does not affect the zoo population size or the number of zoos that keep the family. PMID:23690985

  10. Handedness- and brain size-related efficiency differences in small-world brain networks: a resting-state functional magnetic resonance imaging study.

    PubMed

    Li, Meiling; Wang, Junping; Liu, Feng; Chen, Heng; Lu, Fengmei; Wu, Guorong; Yu, Chunshui; Chen, Huafu

    2015-05-01

    The human brain has been described as a complex network, which integrates information with high efficiency. However, the relationships between the efficiency of human brain functional networks and handedness and brain size remain unclear. Twenty-one left-handed and 32 right-handed healthy subjects underwent a resting-state functional magnetic resonance imaging scan. The whole brain functional networks were constructed by thresholding Pearson correlation matrices of 90 cortical and subcortical regions. Graph theory-based methods were employed to further analyze their topological properties. As expected, all participants demonstrated small-world topology, suggesting a highly efficient topological structure. Furthermore, we found that smaller brains showed higher local efficiency, whereas larger brains showed higher global efficiency, reflecting a suitable efficiency balance between local specialization and global integration of brain functional activity. Compared with right-handers, significant alterations in nodal efficiency were revealed in left-handers, involving the anterior and median cingulate gyrus, middle temporal gyrus, angular gyrus, and amygdala. Our findings indicated that the functional network organization in the human brain was associated with handedness and brain size.

  11. Robert Feulgen Prize Lecture. Grenzgänger: adult bone marrow cells populate the brain.

    PubMed

    Priller, Josef

    2003-08-01

    While the brain has traditionally been considered a rather secluded site, recent studies suggest that adult bone marrow (BM)-derived stem cells can generate glia and neurons in rodents and humans. Macrophages and microglia are the first to appear in the murine brain after transplantation of genetically marked BM cells. Within weeks after transplantation, some authors have found astrocytes and cells expressing neuronal antigens. We detected cerebellar Purkinje neurons and interneurons, such as basket cells, expressing the green fluorescent protein (GFP) 10-15 months after transplantation of GFP-labeled BM cells. The results push the boundaries of our classic view of lineage restriction.

  12. Reorganization and plasticity in the adult brain during learning of motor skills.

    PubMed

    Doyon, Julien; Benali, Habib

    2005-04-01

    On the basis of brain imaging studies, Doyon and Ungerleider recently proposed a model describing the cerebral plasticity that occurs in both cortico-striatal and cortico-cerebellar systems of the adult brain during learning of new motor skilled behaviors. This theoretical framework makes several testable predictions with regards to the contribution of these neural systems based on the phase (fast, slow, consolidation, automatization, and retention) and nature of the motor learning processes (motor sequence versus motor adaptation) acquired through repeated practice. There has been recent behavioral, lesion and additional neuroimaging studies that have addressed the assumptions made in this theory that will help in the revision of this model.

  13. Robert Feulgen Prize Lecture. Grenzgänger: adult bone marrow cells populate the brain.

    PubMed

    Priller, Josef

    2003-08-01

    While the brain has traditionally been considered a rather secluded site, recent studies suggest that adult bone marrow (BM)-derived stem cells can generate glia and neurons in rodents and humans. Macrophages and microglia are the first to appear in the murine brain after transplantation of genetically marked BM cells. Within weeks after transplantation, some authors have found astrocytes and cells expressing neuronal antigens. We detected cerebellar Purkinje neurons and interneurons, such as basket cells, expressing the green fluorescent protein (GFP) 10-15 months after transplantation of GFP-labeled BM cells. The results push the boundaries of our classic view of lineage restriction. PMID:12898276

  14. Brain lesions that impair vocal imitation in adult budgerigars.

    PubMed

    Plummer, Thane K; Striedter, Georg F

    2002-11-15

    Vocal imitation is a complex form of imitative learning that is well developed only in humans, dolphins, and birds. Among birds, only some species are able to imitate sounds in adulthood. Of these, the budgerigar (Melopsittacus undulatus) has been studied in most detail. Previous studies suggested that the vocal motor system in budgerigars receives auditory information from the lateral frontal neostriatum (NFl). In the present study, we confirm this hypothesis by showing that infusions of the GABA agonist muscimol into NFl reduce the strength of auditory responses in a telencephalic vocal motor nucleus, the central nucleus of the lateral neostriatum (NLc). To test whether the auditory information conveyed from NFl to NLc plays a role in vocal imitation, we lesioned parts of NFl and the overlying ventral hyperstriatum (HVl) in seven adult male budgerigars and then examined whether the lesioned males would imitate the calls of females with whom they were paired. We found that, compared to sham-lesioned controls, the lesioned birds were significantly impaired in their imitation of female calls. Yet, the lesioned males were clearly not deaf (e.g., their previously learned calls did not degrade as they do after deafening). Therefore, the data suggest that NFl/HVl lesions impair vocal imitation by reducing the amount of auditory information that reaches the vocal motor system. Interestingly, the females that were paired with lesioned males displayed more vocal plasticity than the females in the control group, and some even imitated their male's prepairing calls.

  15. Pediatric Cancers and Brain Tumors in Adolescents and Young Adults.

    PubMed

    McCabe, Martin G; Valteau-Couanet, Dominique

    2016-01-01

    Embryonal tumors classically occur in young children, some principally within the first year of life. Prospective national and international clinical trials during recent decades have brought about progressive improvements in survival, and associated biological studies have advanced our understanding of tumor biology, in some cases allowing biological tumor characteristics to be harnessed for therapeutic benefit. Embryonal tumors continue to occur, albeit less commonly, during childhood, adolescence and throughout adulthood. These tumors are less well understood, usually not managed according to standardized protocols and rarely included in clinical trials. Survival outcomes are generally poorer than their childhood equivalents. We present here a summary of the published literature on embryonal tumors that present ectopically during adolescence and adulthood. We show that for some tumors protocol-driven treatment, supported by accurate and complete diagnostics and staging, can result in equivalent outcomes to those seen during childhood. We make the case that clinical trial eligibility criteria should be disease-based rather than age-based, and support improvements in dialogue between children's and adults' cancer clinicians to improve outcomes for these rare tumors. PMID:27595358

  16. Role of media and peers on body change strategies among adult men: is body size important?

    PubMed

    McCabe, Marita P; McGreevy, Shauna J

    2011-01-01

    There has been limited previous research that has examined the role of sociocultural influences on body change strategies among adult men. The current study investigated the role of specific types of messages (encouragement, teasing and modelling) from peers and the media on the strategies to change weight among adult men. Differences were evaluated between 526 men aged from 18 to 60 years from three groups (normal weight, overweight and obese) on body image, body change strategies and messages about their body received from peers and the media. Men were primarily drawn from United States, Australia and Europe. Results showed that messages received by men regarding losing weight or increasing muscle size differed according to weight. Body image and media messages were the strongest predictors of losing weight, whereas body image importance and messages from peers were the strongest predictors of increasing muscles. These findings highlight the importance of sociocultural influences on body change strategies among adult males.

  17. Regulation of stroke-induced neurogenesis in adult brain--recent scientific progress.

    PubMed

    Kokaia, Zaal; Thored, Pär; Arvidsson, Andreas; Lindvall, Olle

    2006-07-01

    Stroke induced by middle cerebral artery occlusion in adult rodents induces the formation of new neurons in the damaged striatum, a region that normally does not show neurogenesis. Here we describe recent findings on the regulation of neurogenesis after stroke, in particular regarding the duration of the neurogenic response and the influence of age, as well as the molecular mechanisms influencing migration and survival of the new neurons. We also discuss some crucial issues that need to be addressed in the further exploration of this potential self-repair mechanism after damage to the adult brain. PMID:16766702

  18. Extreme sexual brain size dimorphism in sticklebacks: a consequence of the cognitive challenges of sex and parenting?

    PubMed

    Kotrschal, Alexander; Räsänen, Katja; Kristjánsson, Bjarni K; Senn, Mike; Kolm, Niclas

    2012-01-01

    Selection pressures that act differently on males and females produce numerous differences between the sexes in morphology and behaviour. However, apart from the controversial report that males have slightly heavier brains than females in humans, evidence for substantial sexual dimorphism in brain size is scarce. This apparent sexual uniformity is surprising given that sexually distinct selection pressures are ubiquitous and that brains are one of the most plastic vertebrate organs. Here we demonstrate the highest level of sexual brain size dimorphism ever reported in any vertebrate: male three-spined stickleback of two morphs in an Icelandic lake have 23% heavier brains than females. We suggest that this dramatic sexual size dimorphism is generated by the many cognitively demanding challenges that males are faced in this species, such as an elaborate courtship display, the construction of an ornate nest and a male-only parental care system. However, we consider also alternative explanations for smaller brains in females, such as life-history trade-offs. Our demonstration of unprecedented levels of sexual dimorphism in brain size in the three-spined stickleback implies that behavioural and life-history differences among the sexes can have strong effects also on neural development and proposes new fields of research for understanding brain evolution.

  19. Environmental Impact on Direct Neuronal Reprogramming In Vivo in the Adult Brain

    PubMed Central

    López-Juárez, Alejandro; Howard, Jennifer; Sakthivel, Bhuvaneswari; Aronow, Bruce; Campbell, Kenneth; Nakafuku, Masato

    2013-01-01

    Direct reprogramming of non-neuronal cells to generate new neurons is a promising approach to repair damaged brains. Impact of the in vivo environment on neuronal reprogramming, however, is poorly understood. Here we show that regional differences and injury conditions have significant influence on the efficacy of reprogramming and subsequent survival of newly generated neurons in the adult rodent brain. A combination of local exposure to growth factors and retrovirus-mediated overexpression of the neurogenic transcription factor Neurogenin2 (Neurog2) can induce new neurons from non-neuronal cells in the adult neocortex and striatum where neuronal turnover is otherwise very limited. These two regions respond to growth factors and Neurog2 differently and instruct new neurons to exhibit distinct molecular phenotypes. Moreover, ischemic insult differentially affects differentiation of new neurons in these regions. These results demonstrate strong environmental impact on direct neuronal reprogramming in vivo. PMID:23974433

  20. Environmental impact on direct neuronal reprogramming in vivo in the adult brain.

    PubMed

    Grande, Andrew; Sumiyoshi, Kyoko; López-Juárez, Alejandro; Howard, Jennifer; Sakthivel, Bhuvaneswari; Aronow, Bruce; Campbell, Kenneth; Nakafuku, Masato

    2013-01-01

    Direct reprogramming of non-neuronal cells to generate new neurons is a promising approach to repair damaged brains. Impact of the in vivo environment on neuronal reprogramming, however, is poorly understood. Here we show that regional differences and injury conditions have significant influence on the efficacy of reprogramming and subsequent survival of the newly generated neurons in the adult rodent brain. A combination of local exposure to growth factors and retrovirus-mediated overexpression of the neurogenic transcription factor Neurogenin2 can induce new neurons from non-neuronal cells in the adult neocortex and striatum where neuronal turnover is otherwise very limited. These two regions respond to growth factors and Neurogenin2 differently and instruct new neurons to exhibit distinct molecular phenotypes. Moreover, ischaemic insult differentially affects differentiation of new neurons in these regions. These results demonstrate strong environmental impact on direct neuronal reprogramming in vivo.

  1. Role of astrocytes as neural stem cells in the adult brain

    PubMed Central

    Gonzalez-Perez, Oscar; Quiñones-Hinojosa, Alfredo

    2012-01-01

    In the adult mammalian brain, bona fide neural stem cells were discovered in the subventricular zone (SVZ), the largest neurogenic niche lining the striatal wall of the lateral ventricles of the brain. In this region resides a subpopulation of astrocytes that express the glial fibrillary acidic protein (GFAP), nestin and LeX. Astonishingly, these GFAP-expressing progenitors display stem-cell-like features both in vivo and in vitro. Throughout life SVZ astrocytes give rise to interneurons and oligodendrocyte precursors, which populate the olfactory bulb and the white matter, respectively. The role of the progenies of SVZ astrocytes has not been fully elucidated, but some evidence indicates that the new neurons play a role in olfactory discrimination, whereas oligodendrocytes contribute to myelinate white matter tracts. In this chapter, we describe the astrocytic nature of adult neural stem cells, their organization into the SVZ and some of their molecular and genetic characteristics. PMID:23619383

  2. Bigger Brains or Bigger Nuclei? Regulating the Size of Auditory Structures in Birds

    PubMed Central

    Kubke, M. Fabiana; Massoglia, Dino P.; Carr, Catherine E.

    2012-01-01

    Increases in the size of the neuronal structures that mediate specific behaviors are believed to be related to enhanced computational performance. It is not clear, however, what developmental and evolutionary mechanisms mediate these changes, nor whether an increase in the size of a given neuronal population is a general mechanism to achieve enhanced computational ability. We addressed the issue of size by analyzing the variation in the relative number of cells of auditory structures in auditory specialists and generalists. We show that bird species with different auditory specializations exhibit variation in the relative size of their hindbrain auditory nuclei. In the barn owl, an auditory specialist, the hind-brain auditory nuclei involved in the computation of sound location show hyperplasia. This hyperplasia was also found in songbirds, but not in non-auditory specialists. The hyperplasia of auditory nuclei was also not seen in birds with large body weight suggesting that the total number of cells is selected for in auditory specialists. In barn owls, differences observed in the relative size of the auditory nuclei might be attributed to modifications in neurogenesis and cell death. Thus, hyperplasia of circuits used for auditory computation accompanies auditory specialization in different orders of birds. PMID:14726625

  3. Applications of hybrid diffuse optics for clinical management of adults after brain injury

    NASA Astrophysics Data System (ADS)

    Kim, Meeri Nam

    Information about cerebral blood flow (CBF) is valuable for clinical management of patients after severe brain injury. Unfortunately, current modalities for monitoring brain are often limited by hurdles that include high cost, low throughput, exposure to ionizing radiation, probe invasiveness, and increased risk to critically ill patients when transportation out of their room or unit is required. A further limitation of current technologies is an inability to provide continuous bedside measurements that are often desirable for unstable patients. Here we explore the clinical utility of diffuse correlation spectroscopy (DCS) as an alternative approach for bedside CBF monitoring. DCS uses the rapid intensity fluctuations of near-infrared light to derive a continuous measure of changes in blood flow without ionizing radiation or invasive probing. Concurrently, we employ another optical technique, called diffuse optical spectroscopy (DOS), to derive changes in cerebral oxyhemoglobin ( HbO2) and deoxyhemoglobin (Hb) concentrations. Our clinical studies integrate DCS with DOS into a single hybrid instrument that simultaneously monitors CBF and HbO2/Hb in the injured adult brain. The first parts of this dissertation present the motivations for monitoring blood flow in injured brain, as well as the theory underlying diffuse optics technology. The next section elaborates on details of the hybrid instrumentation. The final chapters describe four human subject studies carried out with these methods. Each of these studies investigates an aspect of the potential of the hybrid monitor in clinical applications involving adult brain. The studies include: (1) validation of DCS-measured CBF against xenon-enhanced computed tomography in brain-injured adults; (2) a study of the effects of age and gender on posture-change-induced CBF variation in healthy subjects; (3) a study of the efficacy of DCS/DOS for monitoring neurocritical care patients during various medical interventions such

  4. Permutation and parametric tests for effect sizes in voxel-based morphometry of gray matter volume in brain structural MRI.

    PubMed

    Dickie, David A; Mikhael, Shadia; Job, Dominic E; Wardlaw, Joanna M; Laidlaw, David H; Bastin, Mark E

    2015-12-01

    Permutation testing has been widely implemented in voxel-based morphometry (VBM) tools. However, this type of non-parametric inference has yet to be thoroughly compared with traditional parametric inference in VBM studies of brain structure. Here we compare both types of inference and investigate what influence the number of permutations in permutation testing has on results in an exemplar study of how gray matter proportion changes with age in a group of working age adults. High resolution T1-weighted volume scans were acquired from 80 healthy adults aged 25-64years. Using a validated VBM procedure and voxel-based permutation testing for Pearson product-moment coefficient, the effect sizes of changes in gray matter proportion with age were assessed using traditional parametric and permutation testing inference with 100, 500, 1000, 5000, 10000 and 20000 permutations. The statistical significance was set at P<0.05 and false discovery rate (FDR) was used to correct for multiple comparisons. Clusters of voxels with statistically significant (PFDR<0.05) declines in gray matter proportion with age identified with permutation testing inference (N≈6000) were approximately twice the size of those identified with parametric inference (N=3221voxels). Permutation testing with 10000 (N=6251voxels) and 20000 (N=6233voxels) permutations produced clusters that were generally consistent with each other. However, with 1000 permutations there were approximately 20% more statistically significant voxels (N=7117voxels) than with ≥10000 permutations. Permutation testing inference may provide a more sensitive method than traditional parametric inference for identifying age-related differences in gray matter proportion. Based on the results reported here, at least 10000 permutations should be used in future univariate VBM studies investigating age related changes in gray matter to avoid potential false findings. Additional studies using permutation testing in large imaging databanks

  5. Eph Receptor and Ephrin Signaling in Developing and Adult Brain of the Honeybee (Apis mellifera)

    PubMed Central

    Vidovic, Maria; Nighorn, Alan; Koblar, Simon; Maleszka, Ryszard

    2007-01-01

    Roles for Eph receptor tyrosine kinase and ephrin signaling in vertebrate brain development are well established. Their involvement in the modulation of mammalian synaptic structure and physiology is also emerging. However, less is known of their effects on brain development and their function in adult invertebrate nervous systems. Here, we report on the characterization of Eph receptor and ephrin orthologs in the honeybee, Apis mellifera (Am), and their role in learning and memory. In situ hybridization for mRNA expression showed a uniform distribution of expression of both genes across the developing pupal and adult brain. However, in situ labeling with Fc fusion proteins indicated that the AmEphR and Amephrin proteins were differentially localized to cell body regions in the mushroom bodies and the developing neuropiles of the antennal and optic lobes. In adults, AmEphR protein was localized to regions of synaptic contacts in optic lobes, in the glomeruli of antennal lobes, and in the medial lobe of the mushroom body. The latter two regions are involved in olfactory learning and memory in the honeybee. Injections of EphR-Fc and ephrin-Fc proteins into the brains of adult bees, 1 h before olfactory conditioning of the proboscis extension reflex, sig-nificantly reduced memory 24 h later. Experimental amnesia in the group injected with ephrin-Fc was apparent 1 h post-training. Experimental amnesia was also induced by post-training injections with ephrin-Fc suggesting a role in recall. This is the first demonstration that Eph molecules function to regulate the formation of memory in insects. PMID:17443785

  6. Adult neurogenesis and cellular brain repair with neural progenitors, precursors and stem cells

    PubMed Central

    Shivraj Sohur, U; Emsley, Jason G; Mitchell, Bartley D; Macklis, Jeffrey D

    2006-01-01

    Recent work in neuroscience has shown that the adult central nervous system (CNS) contains neural progenitors, precursors and stem cells that are capable of generating new neurons, astrocytes and oligodendrocytes. While challenging the previous dogma that no new neurons are born in the adult mammalian CNS, these findings bring with them the future possibilities for development of novel neural repair strategies. The purpose of this review is to present the current knowledge about constitutively occurring adult mammalian neurogenesis, highlight the critical differences between ‘neurogenic’ and ‘non-neurogenic’ regions in the adult brain, and describe the cardinal features of two well-described neurogenic regions—the subventricular zone/olfactory bulb system and the dentate gyrus of the hippocampus. We also provide an overview of presently used models for studying neural precursors in vitro, mention some precursor transplantation models and emphasize that, in this rapidly growing field of neuroscience, one must be cautious with respect to a variety of methodological considerations for studying neural precursor cells both in vitro and in vivo. The possibility of repairing neural circuitry by manipulating neurogenesis is an intriguing one, and, therefore, we also review recent efforts to understand the conditions under which neurogenesis can be induced in non-neurogenic regions of the adult CNS. This work aims towards molecular and cellular manipulation of endogenous neural precursors in situ, without transplantation. We conclude this review with a discussion of what might be the function of newly generated neurons in the adult brain, and provide a summary of present thinking about the consequences of disturbed adult neurogenesis and the reaction of neurogenic regions to disease. PMID:16939970

  7. REGULATION OF NETRIN-1 RECEPTORS BY AMPHETAMINE IN THE ADULT BRAIN

    PubMed Central

    YETNIKOFF, L.; LABELLE-DUMAIS, C.; FLORES, C.

    2016-01-01

    Netrin-1 is a guidance cue molecule fundamental to the organization of neuronal connectivity during development. Netrin-1 and its receptors, deleted in colorectal cancer (DCC) and UNC-5 homologues (UNC-5), continue to be expressed in the adult brain, although neither their function nor the kinds of events that activate their expression are known. Two lines of evidence suggest a role for netrin-1 in amphetamine-induced dopamine plasticity in the adult. First, DCC is highly expressed by adult dopamine neurons. Second, adult mice with reduced DCC levels do not develop amphetamine-induced behavioral sensitization. To explore the role of netrin-1 in amphetamine-induced plasticity, we examined the effects of sensitizing treatment regimens of amphetamine on DCC and/or UNC-5 protein expression in the adult rat. These treatments produced striking and enduring increases in DCC and UNC-5 expression in the cell body, but not terminal regions, of the mesocorticolimbic dopamine system. Notably, neuroadaptations in the cell body region of mesocorticolimbic dopamine neurons underlie the development of sensitization to the effects of amphetamine. Furthermore, these localized amphetamine-induced changes were prevented by co-treatment with an N-methyl-D-aspartate receptor antagonist, a treatment known to block the development of amphetamine-induced sensitization of behavioral activation, dopamine release and motivated behavior. Using immunohistochemistry, we showed that both DCC and UNC-5 receptors are highly expressed by adult mesocorticolimbic dopamine neurons. These results provide the first evidence that repeated exposure to a stimulant drug such as amphetamine affects netrin-1 receptor expression in the adult brain. Taken together, our findings suggest that changes in netrin-1 receptor expression may play a role in the lasting effects of exposure to amphetamine and other stimulant drugs. PMID:17996376

  8. Graph Theory Analysis of Functional Brain Networks and Mobility Disability in Older Adults

    PubMed Central

    Burdette, Jonathan H.; Morgan, Ashley R.; Williamson, Jeff D.; Kritchevsky, Stephen B.; Laurienti, Paul J.

    2014-01-01

    Background. The brain’s structural integrity is associated with mobility function in older adults. Changes in function may be evident earlier than changes in structure and may be more directly related to mobility. Therefore, we assessed whether functional brain networks varied with mobility function in older adults. Methods. Short Physical Performance Battery (SPPB) and resting state functional magnetic resonance imaging were collected on 24 young (mean age = 26.4±5.1) and 48 older (mean age = 72.04±5.1) participants. Older participants were divided into three groups by SPPB score: Low SPPB (score = 7–9), Mid SPPB (score = 10), High SPPB (score = 11–12).Graph theory–based methods were used to characterize and compare brain network organization. Results. Connectivity in the somatomotor cortex distinguished between groups based on SPPB score. The community structure of the somatomotor cortex was significantly less consistent in the Low SPPB group (mean = 0.097±0.05) compared with Young (mean = 0.163±0.09, p = .03) SPPB group. Striking differences were evident in second-order connections between somatomotor cortex and superior temporal gyrus and insula that reached statistical significance. The Low SPPB group (mean = 140.87±109.30) had a significantly higher number of connections than Young (mean = 45.05±33.79, p = .0003) or High (mean = 49.61±35.31, p = .002) SPPB group. Conclusions. Older adults with poorer mobility function exhibited reduced consistency of somatomotor community structure and a greater number of secondary connections with vestibular and multisensory regions of the brain. Further study is needed to fully interpret these effects, but analysis of functional brain networks adds new insights to the contribution of the brain to mobility. PMID:24717331

  9. Central artery stiffness, baroreflex sensitivity, and brain white matter neuronal fiber integrity in older adults.

    PubMed

    Tarumi, Takashi; de Jong, Daan L K; Zhu, David C; Tseng, Benjamin Y; Liu, Jie; Hill, Candace; Riley, Jonathan; Womack, Kyle B; Kerwin, Diana R; Lu, Hanzhang; Munro Cullum, C; Zhang, Rong

    2015-04-15

    Cerebral hypoperfusion elevates the risk of brain white matter (WM) lesions and cognitive impairment. Central artery stiffness impairs baroreflex, which controls systemic arterial perfusion, and may deteriorate neuronal fiber integrity of brain WM. The purpose of this study was to examine the associations among brain WM neuronal fiber integrity, baroreflex sensitivity (BRS), and central artery stiffness in older adults. Fifty-four adults (65 ± 6 years) with normal cognitive function or mild cognitive impairment (MCI) were tested. The neuronal fiber integrity of brain WM was assessed from diffusion metrics acquired by diffusion tensor imaging. BRS was measured in response to acute changes in blood pressure induced by bolus injections of vasoactive drugs. Central artery stiffness was measured by carotid-femoral pulse wave velocity (cfPWV). The WM diffusion metrics including fractional anisotropy (FA) and radial (RD) and axial (AD) diffusivities, BRS, and cfPWV were not different between the control and MCI groups. Thus, the data from both groups were combined for subsequent analyses. Across WM, fiber tracts with decreased FA and increased RD were associated with lower BRS and higher cfPWV, with many of the areas presenting spatial overlap. In particular, the BRS assessed during hypotension was strongly correlated with FA and RD when compared with hypertension. Executive function performance was associated with FA and RD in the areas that correlated with cfPWV and BRS. These findings suggest that baroreflex-mediated control of systemic arterial perfusion, especially during hypotension, may play a crucial role in maintaining neuronal fiber integrity of brain WM in older adults. PMID:25623500

  10. Optimized heterologous transfection of viable adult organotypic brain slices using an enhanced gene gun

    PubMed Central

    2013-01-01

    Background Organotypic brain slices (OTBS) are an excellent experimental compromise between the facility of working with cell cultures and the biological relevance of using animal models where anatomical, morphological, and cellular function of specific brain regions can be maintained. The biological characteristics of OTBS can subsequently be examined under well-defined conditions. They do, however, have a number of limitations; most brain slices are derived from neonatal animals, as it is difficult to properly prepare and maintain adult OTBS. There are ample problems with tissue integrity as OTBS are delicate and frequently become damaged during the preparative stages. Notwithstanding these obstacles, the introduced exogenous proteins into both neuronal cells, and cells imbedded within tissues, have been consistently difficult to achieve. Results Following the ex vivo extraction of adult mouse brains, mounted inside a medium-agarose matrix, we have exploited a precise slicing procedure using a custom built vibroslicer. To transfect these slices we used an improved biolistic transfection method using a custom made low-pressure barrel and novel DNA-coated nanoparticles (40 nm), which are drastically smaller than traditional microparticles. These nanoparticles also minimize tissue damage as seen by a significant reduction in lactate dehydrogenase activity as well as propidium iodide (PI) and dUTP labelling compared to larger traditional gold particles used on these OTBS. Furthermore, following EYFP exogene delivery by gene gun, the 40 nm treated OTBS displayed a significantly larger number of viable NeuN and EYFP positive cells. These OTBS expressed the exogenous proteins for many weeks. Conclusions Our described methodology of producing OTBS, which results in better reproducibility with less tissue damage, permits the exploitation of mature fully formed adult brains for advanced neurobiological studies. The novel 40 nm particles are ideal for the viable

  11. Cognition in an ever-changing world: climatic variability is associated with brain size in Neotropical parrots.

    PubMed

    Schuck-Paim, Cynthia; Alonso, Wladimir J; Ottoni, Eduardo B

    2008-01-01

    Research on the conditions favoring the evolution of complex cognition and its underlying neural structures has increasingly stressed the role of environmental variability. These studies suggest that the ability to learn, behave flexibly and innovate would be favored under unpredictable variations in the availability of resources, as it would enable organisms to adjust to novel conditions. Despite the growing number of studies based on the idea that larger-brained organisms would be better prepared to cope with environmental challenges, direct testing of the association between brain size and environmental variability per se remains scant. Here we focus on Neotropical parrots as our model group and test the hypothesis that if relatively larger brains were favored in climatically variable environments, larger-brained species should currently tolerate a higher degree of environmental uncertainty. Although we show that there are also other factors underlying the dynamics of brain size variation in this group, our results support the hypothesis that proportionally larger-brained species are more tolerant to climatic variability, both on a temporal and spatial scale. Additionally, they suggest that the differences in relative brain size among Neotropical parrots represent multiple, recent events in the evolutionary history of the group, and are particularly tied to an increased dependence on more open and climatically unstable habitats. As this is the first study to present evidence of the link between brain size and climatic variability in birds, our findings provide a step towards understanding the potential benefits underlying variation in brain size and the maintenance of highly enlarged brains in this and other groups.

  12. Neuronal Organization of the Brain in the Adult Amphioxus (Branchiostoma lanceolatum): A Study With Acetylated Tubulin Immunohistochemistry.

    PubMed

    Castro, Antonio; Becerra, Manuela; Manso, María Jesús; Anadón, Ramón

    2015-10-15

    Amphioxus (Cephalochordata) belongs to the most basal extant chordates, and knowledge of their brain organization appears to be key to deciphering the early stages of evolution of vertebrate brains. Most comprehensive studies of the organization of the central nervous system of adult amphioxus have investigated the spinal cord. Some brain populations have been characterized via neurochemistry and electron microscopy, and the overall cytoarchitecture of the brain was studied by Ekhart et al. (2003; J. Comp. Neurol. 466:319-330) with general staining methods and retrograde transport from the spinal cord. Here, the cytoarchitecture of the brain of adult amphioxus Branchiostoma lanceolatum was reinvestigated by using acetylated tubulin immunohistochemistry, which specifically stains neurons and fibers, in combination with some ancillary methods. This method allowed reproducible staining and mapping of types of neuron, mostly in brain regions caudal to the entrance level of nerve 2, and its comparison with spinal cord populations. The brain populations studied and discussed in detail were the Retzius bipolar cells, lamellate cells, Joseph cells, various types of translumenal cells, somatic motoneurons, Rohde nucleus cells, small ventral multipolar neurons, and Edinger cells. These observations expand our knowledge of the distribution of cell types and provide additional data on the number of cells and the axonal tracts and commissural regions of the adult amphioxus brain. The results of this comprehensive study provide a framework for comparison of complex adult populations with the early brain neuronal populations revealed in developmental studies of the amphioxus.

  13. Neuronal Organization of the Brain in the Adult Amphioxus (Branchiostoma lanceolatum): A Study With Acetylated Tubulin Immunohistochemistry.

    PubMed

    Castro, Antonio; Becerra, Manuela; Manso, María Jesús; Anadón, Ramón

    2015-10-15

    Amphioxus (Cephalochordata) belongs to the most basal extant chordates, and knowledge of their brain organization appears to be key to deciphering the early stages of evolution of vertebrate brains. Most comprehensive studies of the organization of the central nervous system of adult amphioxus have investigated the spinal cord. Some brain populations have been characterized via neurochemistry and electron microscopy, and the overall cytoarchitecture of the brain was studied by Ekhart et al. (2003; J. Comp. Neurol. 466:319-330) with general staining methods and retrograde transport from the spinal cord. Here, the cytoarchitecture of the brain of adult amphioxus Branchiostoma lanceolatum was reinvestigated by using acetylated tubulin immunohistochemistry, which specifically stains neurons and fibers, in combination with some ancillary methods. This method allowed reproducible staining and mapping of types of neuron, mostly in brain regions caudal to the entrance level of nerve 2, and its comparison with spinal cord populations. The brain populations studied and discussed in detail were the Retzius bipolar cells, lamellate cells, Joseph cells, various types of translumenal cells, somatic motoneurons, Rohde nucleus cells, small ventral multipolar neurons, and Edinger cells. These observations expand our knowledge of the distribution of cell types and provide additional data on the number of cells and the axonal tracts and commissural regions of the adult amphioxus brain. The results of this comprehensive study provide a framework for comparison of complex adult populations with the early brain neuronal populations revealed in developmental studies of the amphioxus. PMID:25846052

  14. Hippocampal Brain Volume Is Associated with Faster Facial Emotion Identification in Older Adults: Preliminary Results.

    PubMed

    Szymkowicz, Sarah M; Persson, Jonas; Lin, Tian; Fischer, Håkan; Ebner, Natalie C

    2016-01-01

    Quick correct identification of facial emotions is highly relevant for successful social interactions. Research suggests that older, compared to young, adults experience increased difficulty with face and emotion processing skills. While functional neuroimaging studies suggest age differences in neural processing of faces and emotions, evidence about age-associated structural brain changes and their involvement in face and emotion processing is scarce. Using structural magnetic resonance imaging (MRI), this study investigated the extent to which volumes of frontal and temporal brain structures were related to reaction time in accurate identification of facial emotions in 30 young and 30 older adults. Volumetric segmentation was performed using FreeSurfer and gray matter volumes from frontal and temporal regions were extracted. Analysis of covariances (ANCOVAs) models with response time (RT) as the dependent variable and age group and regional volume, and their interaction, as independent variables were conducted, controlling for total intracranial volume (ICV). Results indicated that, in older adults, larger hippocampal volumes were associated with faster correct facial emotion identification. These preliminary observations suggest that greater volume in brain regions associated with face and emotion processing contributes to improved facial emotion identification performance in aging. PMID:27610082

  15. Eating disorder psychopathology, brain structure, neuropsychological correlates and risk mechanisms in very preterm young adults.

    PubMed

    Micali, Nadia; Kothari, Radha; Nam, Kie Woo; Gioroukou, Elena; Walshe, Muriel; Allin, Matthew; Rifkin, Larry; Murray, Robin M; Nosarti, Chiara

    2015-03-01

    This study investigates the prevalence of eating disorder (ED) psychopathology, neuropsychological function, structural brain correlates and risk mechanisms in a prospective cohort of very preterm (VPT) young adults. We assessed ED psychopathology and neuropsychological correlates in 143 cohort individuals born at <33 weeks of gestation. Structural brain correlates and risk factors at birth, in childhood and adolescence, were investigated using prospectively collected data throughout childhood/adolescence. VPT-born individuals had high levels of ED psychopathology at age 21 years. Executive function did not correlate with ED symptomatology. VPT adults presenting with ED psychopathology had smaller grey matter volume at age 14/15 years in the left posterior cerebellum and smaller white matter volume in the fusiform gyrus bilaterally, compared with VPT adults with no ED psychopathology. Caesarean delivery predicted engaging in compensatory behaviours, and severe eating difficulty at age 14 years predicted ED symptomatology in young adulthood. VPT individuals are at risk for ED symptomatology, with evidence of associated structural alterations in posterior brain regions. Further prospective studies are needed to clarify the pathways that lead from perinatal/obstetric complications to ED and relevant neurobiological mechanisms. © 2015 The Authors. European Eating Disorders Review published by John Wiley &Sons, Ltd.

  16. Hippocampal Brain Volume Is Associated with Faster Facial Emotion Identification in Older Adults: Preliminary Results

    PubMed Central

    Szymkowicz, Sarah M.; Persson, Jonas; Lin, Tian; Fischer, Håkan; Ebner, Natalie C.

    2016-01-01

    Quick correct identification of facial emotions is highly relevant for successful social interactions. Research suggests that older, compared to young, adults experience increased difficulty with face and emotion processing skills. While functional neuroimaging studies suggest age differences in neural processing of faces and emotions, evidence about age-associated structural brain changes and their involvement in face and emotion processing is scarce. Using structural magnetic resonance imaging (MRI), this study investigated the extent to which volumes of frontal and temporal brain structures were related to reaction time in accurate identification of facial emotions in 30 young and 30 older adults. Volumetric segmentation was performed using FreeSurfer and gray matter volumes from frontal and temporal regions were extracted. Analysis of covariances (ANCOVAs) models with response time (RT) as the dependent variable and age group and regional volume, and their interaction, as independent variables were conducted, controlling for total intracranial volume (ICV). Results indicated that, in older adults, larger hippocampal volumes were associated with faster correct facial emotion identification. These preliminary observations suggest that greater volume in brain regions associated with face and emotion processing contributes to improved facial emotion identification performance in aging.

  17. Hippocampal Brain Volume Is Associated with Faster Facial Emotion Identification in Older Adults: Preliminary Results

    PubMed Central

    Szymkowicz, Sarah M.; Persson, Jonas; Lin, Tian; Fischer, Håkan; Ebner, Natalie C.

    2016-01-01

    Quick correct identification of facial emotions is highly relevant for successful social interactions. Research suggests that older, compared to young, adults experience increased difficulty with face and emotion processing skills. While functional neuroimaging studies suggest age differences in neural processing of faces and emotions, evidence about age-associated structural brain changes and their involvement in face and emotion processing is scarce. Using structural magnetic resonance imaging (MRI), this study investigated the extent to which volumes of frontal and temporal brain structures were related to reaction time in accurate identification of facial emotions in 30 young and 30 older adults. Volumetric segmentation was performed using FreeSurfer and gray matter volumes from frontal and temporal regions were extracted. Analysis of covariances (ANCOVAs) models with response time (RT) as the dependent variable and age group and regional volume, and their interaction, as independent variables were conducted, controlling for total intracranial volume (ICV). Results indicated that, in older adults, larger hippocampal volumes were associated with faster correct facial emotion identification. These preliminary observations suggest that greater volume in brain regions associated with face and emotion processing contributes to improved facial emotion identification performance in aging. PMID:27610082

  18. Reawakening the sleeping beauty in the adult brain: neurogenesis from parenchymal glia.

    PubMed

    Péron, Sophie; Berninger, Benedikt

    2015-10-01

    Life-long neurogenesis is highly restricted to specialized niches in the adult mammalian brain and therefore the brain's capacity for spontaneous regeneration is extremely limited. However, recent work has demonstrated that under certain circumstances parenchymal astrocytes and NG2 glia can generate neuronal progeny. In the striatum, stroke or excitotoxic lesions can reawaken in astrocytes a latent neurogenic program resulting in the genesis of new neurons. By contrast, in brain areas that fail to mount a neurogenic response following injury, such as the cerebral cortex, forced expression of neurogenic reprogramming factors can lineage convert local glia into induced neurons. Yet, injury-induced and reprogramming-induced neurogenesis exhibit intriguing commonalities, suggesting that they may converge on similar mechanisms.

  19. Children and Adults Use Physical Size and Numerical Alliances in Third-Party Judgments of Dominance

    PubMed Central

    Lourenco, Stella F.; Bonny, Justin W.; Schwartz, Bari L.

    2016-01-01

    Humans and other social animals interact regularly with conspecifics as part of affiliative groups. Many of these interactions are cooperative, but many others involve competition for resources. Competitive exchanges are often resolved on the basis of dominance relationships, with higher-ranking individuals receiving priority access to desired goods. Although no single cue can establish permanent dominance relationships, there are some cues that predict dominance fairly reliably across context. In the present study, we focused on two such cues relevant to competing groups: (i) the physical sizes of individual members, and (ii) their relative number. Using a social competition task, we examined whether, and how, preschool-aged children and adults used differences in physical size and numerical alliances to judge which of two groups should prevail in a competitive exchange for a desired object. These judgments were made when either physical size or number differed between groups (Experiment 1), and when both were available but pitted against each other (Experiments 1 and 2). Our findings revealed that by 3 years of age, humans use multiple perceptible cues in third-party judgments of dominance. Our findings also revealed that 3-year-olds, like adults, weighted these cues flexibly according to the additional factor of overall group size, with the physical sizes of individuals determining dominance in smaller groups (e.g., 2 vs. 4 characters) and the relative number of individuals determining dominance in larger groups (e.g., 15 vs. 30 characters). Taken together, our findings suggest that a basic formula for determining dominance in competitive exchanges, which weights physical size of individuals and numerical alliances as a function of overall group size, is available to young children and appears fairly stable through to adulthood. PMID:26793158

  20. Neurodevelopmental LincRNA Microsyteny Conservation and Mammalian Brain Size Evolution

    PubMed Central

    Lewitus, Eric; Huttner, Wieland B.

    2015-01-01

    The mammalian neocortex has undergone repeated selection for increases and decreases in size and complexity, often over relatively short evolutionary time. But because probing developmental mechanisms across many species is experimentally unfeasible, it is unknown whether convergent morphologies in distantly related species are regulated by conserved developmental programs. In this work, we have taken advantage of the abundance of available mammalian genomes to find evidence of selection on genomic regions putatively regulating neurogenesis in large- versus small-brained species. Using published fetal human RNA-seq data, we show that the gene-neighborhood (i.e., microsynteny) of long intergenic non-coding RNAs (lincRNAs) implicated in cortical development is differentially conserved in large-brained species, lending support to the hypothesis that lincRNAs regulating neurogenesis are selectively lost in small-brained species. We provide evidence that this is not a phenomenon attributable to lincRNA expressed in all tissue types and is therefore likely to represent an adaptive function in the evolution of neurogenesis. A strong correlation between transcription factor-adjacency and lincRNA sequence conservation reinforces this conclusion. PMID:26134977

  1. Do smart birds stress less? An interspecific relationship between brain size and corticosterone levels.

    PubMed

    Lendvai, Ádám Z; Bókony, Veronika; Angelier, Frédéric; Chastel, Olivier; Sol, Daniel

    2013-11-01

    Vertebrates respond to unpredictable noxious environmental stimuli by increasing secretion of glucocorticoids (CORT). Although this hormonal stress response is adaptive, high levels of CORT may induce significant costs if stressful situations are frequent. Thus, alternative coping mechanisms that help buffer individuals against environmental stressors may be selected for when the costs of CORT levels are elevated. By allowing individuals to identify, anticipate and cope with the stressful circumstances, cognition may enable stress-specific behavioural coping. Although there is evidence that behavioural responses allow animals to cope with stressful situations, it is unclear whether or not cognition reduces investment in the neuroendocrine stress response. Here, we report that in birds, species with larger brains relative to their body size show lower baseline and peak CORT levels than species with smaller brains. This relationship is consistent across life-history stages, and cannot be accounted for by differences in life history and geographical latitude. Because a large brain is a major feature of birds that base their lifetime in learning new things, our results support the hypothesis that enhanced cognition represents a general alternative to the neuroendocrine stress response.

  2. Do smart birds stress less? An interspecific relationship between brain size and corticosterone levels

    PubMed Central

    Lendvai, Ádám Z.; Bókony, Veronika; Angelier, Frédéric; Chastel, Olivier; Sol, Daniel

    2013-01-01

    Vertebrates respond to unpredictable noxious environmental stimuli by increasing secretion of glucocorticoids (CORT). Although this hormonal stress response is adaptive, high levels of CORT may induce significant costs if stressful situations are frequent. Thus, alternative coping mechanisms that help buffer individuals against environmental stressors may be selected for when the costs of CORT levels are elevated. By allowing individuals to identify, anticipate and cope with the stressful circumstances, cognition may enable stress-specific behavioural coping. Although there is evidence that behavioural responses allow animals to cope with stressful situations, it is unclear whether or not cognition reduces investment in the neuroendocrine stress response. Here, we report that in birds, species with larger brains relative to their body size show lower baseline and peak CORT levels than species with smaller brains. This relationship is consistent across life-history stages, and cannot be accounted for by differences in life history and geographical latitude. Because a large brain is a major feature of birds that base their lifetime in learning new things, our results support the hypothesis that enhanced cognition represents a general alternative to the neuroendocrine stress response. PMID:24026820

  3. Extremely low frequency electromagnetic fields (EMF) and brain cancer in adults and children: review and comment.

    PubMed Central

    Gurney, J. G.; van Wijngaarden, E.

    1999-01-01

    Epidemiologic and experimental research on the potential carcinogenic effects of extremely low frequency electromagnetic fields (EMF) has now been conducted for over two decades. Cancer epidemiology studies in relation to EMF have focused primarily on brain cancer and leukemia, both from residential sources of exposure in children and adults and from occupational exposure in adult men. Because genotoxic effects of EMF have not been shown, most recent laboratory research has attempted to show biological effects that could be related to cancer promotion. In this report, we briefly review residential and occupational EMF studies on brain cancer. We also provide a general review of experimental studies as they relate both to the biological plausibility of an EMF-brain cancer relation and to the insufficiency of such research to help guide exposure assessment in epidemiologic studies. We conclude from our review that no recent research, either epidemiologic or experimental, has emerged to provide reasonable support for a causal role of EMF on brain cancer. PMID:11550314

  4. Brain white matter structure and COMT gene are linked to second-language learning in adults.

    PubMed

    Mamiya, Ping C; Richards, Todd L; Coe, Bradley P; Eichler, Evan E; Kuhl, Patricia K

    2016-06-28

    Adult human brains retain the capacity to undergo tissue reorganization during second-language learning. Brain-imaging studies show a relationship between neuroanatomical properties and learning for adults exposed to a second language. However, the role of genetic factors in this relationship has not been investigated. The goal of the current study was twofold: (i) to characterize the relationship between brain white matter fiber-tract properties and second-language immersion using diffusion tensor imaging, and (ii) to determine whether polymorphisms in the catechol-O-methyltransferase (COMT) gene affect the relationship. We recruited incoming Chinese students enrolled in the University of Washington and scanned their brains one time. We measured the diffusion properties of the white matter fiber tracts and correlated them with the number of days each student had been in the immersion program at the time of the brain scan. We found that higher numbers of days in the English immersion program correlated with higher fractional anisotropy and lower radial diffusivity in the right superior longitudinal fasciculus. We show that fractional anisotropy declined once the subjects finished the immersion program. The relationship between brain white matter fiber-tract properties and immersion varied in subjects with different COMT genotypes. Subjects with the Methionine (Met)/Valine (Val) and Val/Val genotypes showed higher fractional anisotropy and lower radial diffusivity during immersion, which reversed immediately after immersion ended, whereas those with the Met/Met genotype did not show these relationships. Statistical modeling revealed that subjects' grades in the language immersion program were best predicted by fractional anisotropy and COMT genotype. PMID:27298360

  5. Brain white matter structure and COMT gene are linked to second-language learning in adults.

    PubMed

    Mamiya, Ping C; Richards, Todd L; Coe, Bradley P; Eichler, Evan E; Kuhl, Patricia K

    2016-06-28

    Adult human brains retain the capacity to undergo tissue reorganization during second-language learning. Brain-imaging studies show a relationship between neuroanatomical properties and learning for adults exposed to a second language. However, the role of genetic factors in this relationship has not been investigated. The goal of the current study was twofold: (i) to characterize the relationship between brain white matter fiber-tract properties and second-language immersion using diffusion tensor imaging, and (ii) to determine whether polymorphisms in the catechol-O-methyltransferase (COMT) gene affect the relationship. We recruited incoming Chinese students enrolled in the University of Washington and scanned their brains one time. We measured the diffusion properties of the white matter fiber tracts and correlated them with the number of days each student had been in the immersion program at the time of the brain scan. We found that higher numbers of days in the English immersion program correlated with higher fractional anisotropy and lower radial diffusivity in the right superior longitudinal fasciculus. We show that fractional anisotropy declined once the subjects finished the immersion program. The relationship between brain white matter fiber-tract properties and immersion varied in subjects with different COMT genotypes. Subjects with the Methionine (Met)/Valine (Val) and Val/Val genotypes showed higher fractional anisotropy and lower radial diffusivity during immersion, which reversed immediately after immersion ended, whereas those with the Met/Met genotype did not show these relationships. Statistical modeling revealed that subjects' grades in the language immersion program were best predicted by fractional anisotropy and COMT genotype.

  6. Brain white matter structure and COMT gene are linked to second-language learning in adults

    PubMed Central

    Mamiya, Ping C.; Richards, Todd L.; Coe, Bradley P.; Eichler, Evan E.; Kuhl, Patricia K.

    2016-01-01

    Adult human brains retain the capacity to undergo tissue reorganization during second-language learning. Brain-imaging studies show a relationship between neuroanatomical properties and learning for adults exposed to a second language. However, the role of genetic factors in this relationship has not been investigated. The goal of the current study was twofold: (i) to characterize the relationship between brain white matter fiber-tract properties and second-language immersion using diffusion tensor imaging, and (ii) to determine whether polymorphisms in the catechol-O-methyltransferase (COMT) gene affect the relationship. We recruited incoming Chinese students enrolled in the University of Washington and scanned their brains one time. We measured the diffusion properties of the white matter fiber tracts and correlated them with the number of days each student had been in the immersion program at the time of the brain scan. We found that higher numbers of days in the English immersion program correlated with higher fractional anisotropy and lower radial diffusivity in the right superior longitudinal fasciculus. We show that fractional anisotropy declined once the subjects finished the immersion program. The relationship between brain white matter fiber-tract properties and immersion varied in subjects with different COMT genotypes. Subjects with the Methionine (Met)/Valine (Val) and Val/Val genotypes showed higher fractional anisotropy and lower radial diffusivity during immersion, which reversed immediately after immersion ended, whereas those with the Met/Met genotype did not show these relationships. Statistical modeling revealed that subjects’ grades in the language immersion program were best predicted by fractional anisotropy and COMT genotype. PMID:27298360

  7. Deformable adult human phantoms for radiation protection dosimetry: anthropometric data representing size distributions of adult worker populations and software algorithms

    NASA Astrophysics Data System (ADS)

    Hum Na, Yong; Zhang, Binquan; Zhang, Juying; Caracappa, Peter F.; Xu, X. George

    2010-07-01

    Computational phantoms representing workers and patients are essential in estimating organ doses from various occupational radiation exposures and medical procedures. Nearly all existing phantoms, however, were purposely designed to match internal and external anatomical features of the Reference Man as defined by the International Commission on Radiological Protection (ICRP). To reduce uncertainty in dose calculations caused by anatomical variations, a new generation of phantoms of varying organ and body sizes is needed. This paper presents detailed anatomical data in tables and graphs that are used to design such size-adjustable phantoms representing a range of adult individuals in terms of the body height, body weight and internal organ volume/mass. Two different sets of information are used to derive the phantom sets: (1) individual internal organ size and volume/mass distribution data derived from the recommendations of the ICRP in Publications 23 and 89 and (2) whole-body height and weight percentile data from the National Health and Nutrition Examination Survey (NHANES 1999-2002). The NHANES height and weight data for 19 year old males and females are used to estimate the distributions of individuals' size, which is unknown, that corresponds to the ICRP organ and tissue distributions. This paper then demonstrates the usage of these anthropometric data in the development of deformable anatomical phantoms. A pair of phantoms—modeled entirely in mesh surfaces—of the adult male and female, RPI-adult male (AM) and RPI-adult female (AF) are used as the base for size-adjustable phantoms. To create percentile-specific phantoms from these two base phantoms, organ surface boundaries are carefully altered according to the tabulated anthropometric data. Software algorithms are developed to automatically match the organ volumes and masses with desired values. Finally, these mesh-based, percentile-specific phantoms are converted into voxel-based phantoms for Monte

  8. Deformable adult human phantoms for radiation protection dosimetry: anthropometric data representing size distributions of adult worker populations and software algorithms.

    PubMed

    Na, Yong Hum; Zhang, Binquan; Zhang, Juying; Caracappa, Peter F; Xu, X George

    2010-07-01

    Computational phantoms representing workers and patients are essential in estimating organ doses from various occupational radiation exposures and medical procedures. Nearly all existing phantoms, however, were purposely designed to match internal and external anatomical features of the Reference Man as defined by the International Commission on Radiological Protection (ICRP). To reduce uncertainty in dose calculations caused by anatomical variations, a new generation of phantoms of varying organ and body sizes is needed. This paper presents detailed anatomical data in tables and graphs that are used to design such size-adjustable phantoms representing a range of adult individuals in terms of the body height, body weight and internal organ volume/mass. Two different sets of information are used to derive the phantom sets: (1) individual internal organ size and volume/mass distribution data derived from the recommendations of the ICRP in Publications 23 and 89 and (2) whole-body height and weight percentile data from the National Health and Nutrition Examination Survey (NHANES 1999-2002). The NHANES height and weight data for 19 year old males and females are used to estimate the distributions of individuals' size, which is unknown, that corresponds to the ICRP organ and tissue distributions. This paper then demonstrates the usage of these anthropometric data in the development of deformable anatomical phantoms. A pair of phantoms--modeled entirely in mesh surfaces--of the adult male and female, RPI-adult male (AM) and RPI-adult female (AF) are used as the base for size-adjustable phantoms. To create percentile-specific phantoms from these two base phantoms, organ surface boundaries are carefully altered according to the tabulated anthropometric data. Software algorithms are developed to automatically match the organ volumes and masses with desired values. Finally, these mesh-based, percentile-specific phantoms are converted into voxel-based phantoms for Monte Carlo

  9. Brain stem melanocortinergic modulation of meal size and identification of hypothalamic POMC projections.

    PubMed

    Zheng, Huiyuan; Patterson, Laurel M; Phifer, Curtis B; Berthoud, Hans-Rudolf

    2005-07-01

    Metabolic, cognitive, and environmental factors processed in the forebrain modulate food intake by changing the potency of direct controls of meal ingestion in the brain stem. Here, we behaviorally and anatomically test the role of the hypothalamic proopiomelanocortin (POMC) system in mediating some of these descending, indirect controls. Melanotan II (MTII), a stable melanocortin 4 receptor (MC4R) and melanocortin 3 receptor (MC3R) agonist injected into the fourth ventricle near the dorsal vagal complex, potently inhibited 14-h food intake by decreasing meal size but not meal frequency; SHU9119, an antagonist, increased food intake by selectively increasing meal size. Furthermore, MTII injected into the fourth ventricle increased and SHU9119 tended to decrease heart rate and body temperature measured telemetrically in freely moving rats. Numerous alpha-melanocyte-stimulating hormone-immunoreactive axons were in close anatomical apposition to nucleus tractus solitarius neurons showing c-Fos in response to gastric distension, expressing neurochemical phenotypes implicated in ingestive control, and projecting to brown adipose tissue. In retrograde tracing experiments, a small percentage of arcuate nucleus POMC neurons was found to project to the dorsal vagal complex. Thus melanocortin signaling in the brain stem is sufficient to alter food intake via changing the potency of satiety signals and to alter sympathetic outflow. Although the anatomical findings support the involvement of hypothalamomedullary POMC projections in mediating part of the descending, indirect signal, they do not rule out involvement of POMC neurons in the nucleus tractus solitarius in mediating part of the direct signal.

  10. p21-Activated kinases 1 and 3 control brain size through coordinating neuronal complexity and synaptic properties.

    PubMed

    Huang, Wayne; Zhou, Zikai; Asrar, Suhail; Henkelman, Mark; Xie, Wei; Jia, Zhengping

    2011-02-01

    The molecular mechanisms that coordinate postnatal brain enlargement, synaptic properties, and cognition remain an enigma. Here, we demonstrate that neuronal complexity controlled by p21-activated kinases (PAKs) is a key determinant for postnatal brain enlargement and synaptic properties. We showed that double-knockout (DK) mice lacking both PAK1 and PAK3 were born healthy, with normal brain size and structure, but severely impaired in postnatal brain growth, resulting in a dramatic reduction in brain volume. Remarkably, the reduced brain size was accompanied by minimal changes in total cell count, due to a significant increase in cell density. However, the DK neurons have smaller soma, markedly simplified dendritic arbors/axons, and reduced synapse density. Surprisingly, the DK mice had elevated basal synaptic responses due to enhanced individual synaptic potency but were severely impaired in bidirectional synaptic plasticity. The actions of PAK1 and PAK3 are possibly mediated by cofilin-dependent actin regulation, because the activity of cofilin and the properties of actin filaments were altered in the DK mice. These results reveal an essential in vivo role of PAK1 and PAK3 in coordinating neuronal complexity and synaptic properties and highlight the critical importance of dendrite/axon growth in dictating postnatal brain growth and attainment of normal brain size and function.

  11. Intervention-induced enhancement in intrinsic brain activity in healthy older adults

    PubMed Central

    Yin, Shufei; Zhu, Xinyi; Li, Rui; Niu, Yanan; Wang, Baoxi; Zheng, Zhiwei; Huang, Xin; Huo, Lijuan; Li, Juan

    2014-01-01

    This study examined the effects of a multimodal intervention on spontaneous brain activity in healthy older adults. Seventeen older adults received a six-week intervention that consisted of cognitive training, Tai Chi exercise, and group counseling, while 17 older adults in a control group attended health knowledge lectures. The intervention group demonstrated enhanced memory and social support compared to the control group. The amplitude of low frequency fluctuations (ALFF) in the middle frontal gyrus, superior frontal gyrus, and anterior cerebellum lobe was enhanced for the intervention group, while the control group showed reduced ALFF in these three regions. Moreover, changes in trail-making performance and well-being could be predicted by the intervention-induced changes in ALFF. Additionally, individual differences in the baseline ALFF were correlated with intervention-related changes in behavioral performance. These findings suggest that a multimodal intervention is effective in improving cognitive functions and well-being and can induce functional changes in the aging brain. The study extended previous training studies by suggesting resting-state ALFF as a marker of intervention-induced plasticity in older adults. PMID:25472002

  12. Functional brain connectivity and cognition: effects of adult age and task demands.

    PubMed

    Chou, Ying-Hui; Chen, Nan-Kuei; Madden, David J

    2013-08-01

    Previous neuroimaging research has documented that patterns of intrinsic (resting state) functional connectivity (FC) among brain regions covary with individual measures of cognitive performance. Here, we examined the relation between intrinsic FC and a reaction time (RT) measure of performance, as a function of age group and task demands. We obtained filtered, event-related functional magnetic resonance imaging data, and RT measures of visual search performance, from 21 younger adults (19-29 years old) and 21 healthy, older adults (60-87 years old). Age-related decline occurred in the connectivity strength in multiple brain regions, consistent with previous findings. Among 8 pairs of regions, across somatomotor, orbitofrontal, and subcortical networks, increasing FC was associated with faster responding (lower RT). Relative to younger adults, older adults exhibited a lower strength of this RT-connectivity relation and greater disruption of this relation by a salient but irrelevant display item (color singleton distractor). Age-related differences in the covariation of intrinsic FC and cognitive performance vary as a function of task demands.

  13. SPM95 sensitivity to size, intensity and asymmetry of brain activation/deactivation patterns

    SciTech Connect

    Levy, A.V.; Volkow, N.D.; Alexoff, D.

    1996-05-01

    Statistical Parametric Mapping (Friston, SPM95), is used widely to ascertain the statistical significance between different brain patterns induced by functional activation, drug, effects or mental illness. Our purpose is to understand the limitations of applying the SPM95 methodology. We used a group of 8 FDG PET (CTI 931) studies from normal resting human subjects and via software we activated or deactivated the same specific pixel patterns (ROIs), across the group and observed if SPM95 performed correctly. A set of 6 experiments was designed with varying ROI intensities, (from +/-2% to +/-100% of original ROI value), varying ROI sizes, (from 76 to 656 mm{sup 2}) and different locations in the brain, (cortical and/or subcortical). In experiments where the selected activation pattern was spatially symmetric SPM95 identified correctly areas of activation for cortical ROIs as small as 76 mm{sup 2} having as low as a 10% activation with p<0.01; larger areas, 656 mm{sup 2} can be correctly identified even down to only 2%. In activation experiments with left/right cortical or anterior/posterior cortical asymmetry, SPM95 reported Type II errors for levels larger than +/-20% activation/deactivation. In experiments with left/right striatum asymmetry larger than +/-20% SPM95 reported Type I Errors. In experiments where the level of asymmetry was changes while keeping one ROI as a control at the same level of activation, SPM95 erroneously reported different p values for its statistical significance. One of the typical Type I Errors is shown in the figure as an ROI along the brain`s edge; this type of error has been previously observed to be caused by residual spatial registration errors that induce false activation signals. We conclude that while the statistical part of SPM95 performs correctly, the spatial registration method used in SPM95 has residual registration errors sensitive to the type of activation pattern.

  14. Prion diseases and adult neurogenesis: how do prions counteract the brain's endogenous repair machinery?

    PubMed

    Relaño-Ginés, Aroa; Lehmann, Sylvain; Crozet, Carole

    2014-01-01

    Scientific advances in stem cell biology and adult neurogenesis have raised the hope that neurodegenerative disorders could benefit from stem cell-based therapy. Adult neurogenesis might be part of the physiological regenerative process, however it might become impaired by the disease's mechanism and therefore contribute to neurodegeneration. In prion disorders this endogenous repair system has rarely been studied. Whether adult neurogenesis plays a role or not in brain repair or in the propagation of prion pathology remains unclear. We have recently investigated the status of adult neural stem cells isolated from prion-infected mice. We were able to show that neural stem cells accumulate and replicate prions thus resulting in an alteration of their neuronal destiny. We also reproduced these results in adult neural stem cells, which were infected in vitro. The fact that endogenous adult neurogenesis could be altered by the accumulation of misfolded prion protein represents another great challenge. Inhibiting prion propagation in these cells would thus help the endogenous neurogenesis to compensate for the injured neuronal system. Moreover, understanding the endogenous modulation of the neurogenesis system would help develop effective neural stem cell-based therapies.

  15. In Vivo MRI Mapping of Brain Iron Deposition across the Adult Lifespan

    PubMed Central

    Betts, Matthew J.; Cardenas-Blanco, Arturo; Yang, Shan; Nestor, Peter J.

    2016-01-01

    Disruption of iron homeostasis as a consequence of aging is thought to cause iron levels to increase, potentially promoting oxidative cellular damage. Therefore, understanding how this process evolves through the lifespan could offer insights into both the aging process and the development of aging-related neurodegenerative brain diseases. This work aimed to map, in vivo for the first time with an unbiased whole-brain approach, age-related iron changes using quantitative susceptibility mapping (QSM)—a new postprocessed MRI contrast mechanism. To this end, a full QSM standardization routine was devised and a cohort of N = 116 healthy adults (20–79 years of age) was studied. The whole-brain and ROI analyses confirmed that the propensity of brain cells to accumulate excessive iron as a function of aging largely depends on their exact anatomical location. Whereas only patchy signs of iron scavenging were observed in white matter, strong, bilateral, and confluent QSM–age associations were identified in several deep-brain nuclei—chiefly the striatum and midbrain—and across motor, premotor, posterior insular, superior prefrontal, and cerebellar cortices. The validity of QSM as a suitable in vivo imaging technique with which to monitor iron dysregulation in the human brain was demonstrated by confirming age-related increases in several subcortical nuclei that are known to accumulate iron with age. The study indicated that, in addition to these structures, there is a predilection for iron accumulation in the frontal lobes, which when combined with the subcortical findings, suggests that iron accumulation with age predominantly affects brain regions concerned with motor/output functions. SIGNIFICANCE STATEMENT This study used a whole-brain imaging approach known as quantitative susceptibility mapping (QSM) to provide a novel insight into iron accumulation in the brain across the adult lifespan. Validity of the method was demonstrated by showing concordance with ROI

  16. Persistent production of neurons from adult brain stem cells during recovery after stroke.

    PubMed

    Thored, Pär; Arvidsson, Andreas; Cacci, Emanuele; Ahlenius, Henrik; Kallur, Therése; Darsalia, Vladimer; Ekdahl, Christine T; Kokaia, Zaal; Lindvall, Olle

    2006-03-01

    Neural stem cells in the subventricular zone of adult rodents produce new striatal neurons that may replace those that have died after stroke; however, the neurogenic response has been considered acute and transient, yielding only small numbers of neurons. In contrast, we show herein that striatal neuroblasts are generated without decline at least for 4 months after stroke in adult rats. Neuroblasts formed early or late after stroke either differentiate into mature neurons, which survive for several months, or die through caspase-mediated apoptosis. The directed migration of the new neurons toward the ischemic damage is regulated by stromal cell-derived factor-1alpha and its receptor CXCR4. These results show that endogenous neural stem cells continuously supply the injured adult brain with new neurons, which suggests novel self-repair strategies to improve recovery after stroke. PMID:16210404

  17. Association of Overweight with Food Portion Size among Adults of São Paulo – Brazil

    PubMed Central

    Mendes, Aline; Crispim, Sandra Patricia; Marchioni, Dirce Maria; Fisberg, Regina Mara

    2016-01-01

    Background Although studies show that portion size affects energy intake, few have demonstrated a link between portion size and weight status, especially in free-living populations. The objective of the present study was to assess the relationship between food portion sizes and overweight in a representative population of adults of São Paulo, Brazil. Methods Cross-sectional population-based study with 1005 adults from São Paulo, Brazil. Dietary data were obtained from two 24-hour recalls. Reported foods were classified into groups and energy contribution, prevalence of consumers and portion sizes were calculated. Individuals were classified according to BMI in with and without overweight. Logistic regression models were used to evaluate the association between food portion sizes and being overweight. Results The most consumed food groups were: beans, breads/rolls, coffee/tea, milk, rice, and sugar. Rice, red meat, breads/rolls, and white meat were the groups with the highest percentage of contribution to total energy intake. Butter/margarine, toasts/biscuits, sugar, and cakes were the groups with the highest energy density. After adjustment for confounding variables, overweight was associated with larger portions of pizza (OR = 1.052; p = 0.048), red meat (OR = 1.025; p = 0.043), rice (OR = 1.033; p<0.001), salted snacks (OR = 1.078; p = 0.022), and soft drinks (OR = 1.016; p = 0.007). Conclusions Larger portions of few food groups with different energy densities were associated with being overweight, suggesting that overweight may be related to the consumption of larger portion sizes of a series of food groups, not a food group alone. Additionally, we highlight the importance of considering underreporting as a confounding factor in these associations. PMID:27706222

  18. Scale-Dependent Habitat Selection and Size-Based Dominance in Adult Male American Alligators.

    PubMed

    Strickland, Bradley A; Vilella, Francisco J; Belant, Jerrold L

    2016-01-01

    Habitat selection is an active behavioral process that may vary across spatial and temporal scales. Animals choose an area of primary utilization (i.e., home range) then make decisions focused on resource needs within patches. Dominance may affect the spatial distribution of conspecifics and concomitant habitat selection. Size-dependent social dominance hierarchies have been documented in captive alligators, but evidence is lacking from wild populations. We studied habitat selection for adult male American alligators (Alligator mississippiensis; n = 17) on the Pearl River in central Mississippi, USA, to test whether habitat selection was scale-dependent and individual resource selectivity was a function of conspecific body size. We used K-select analysis to quantify selection at the home range scale and patches within the home range to determine selection congruency and important habitat variables. In addition, we used linear models to determine if body size was related to selection patterns and strengths. Our results indicated habitat selection of adult male alligators was a scale-dependent process. Alligators demonstrated greater overall selection for habitat variables at the patch level and less at the home range level, suggesting resources may not be limited when selecting a home range for animals in our study area. Further, diurnal habitat selection patterns may depend on thermoregulatory needs. There was no relationship between resource selection or home range size and body size, suggesting size-dependent dominance hierarchies may not have influenced alligator resource selection or space use in our sample. Though apparent habitat suitability and low alligator density did not manifest in an observed dominance hierarchy, we hypothesize that a change in either could increase intraspecific interactions, facilitating a dominance hierarchy. Due to the broad and diverse ecological roles of alligators, understanding the factors that influence their social dominance

  19. Scale-Dependent Habitat Selection and Size-Based Dominance in Adult Male American Alligators

    PubMed Central

    Strickland, Bradley A.; Vilella, Francisco J.; Belant, Jerrold L.

    2016-01-01

    Habitat selection is an active behavioral process that may vary across spatial and temporal scales. Animals choose an area of primary utilization (i.e., home range) then make decisions focused on resource needs within patches. Dominance may affect the spatial distribution of conspecifics and concomitant habitat selection. Size-dependent social dominance hierarchies have been documented in captive alligators, but evidence is lacking from wild populations. We studied habitat selection for adult male American alligators (Alligator mississippiensis; n = 17) on the Pearl River in central Mississippi, USA, to test whether habitat selection was scale-dependent and individual resource selectivity was a function of conspecific body size. We used K-select analysis to quantify selection at the home range scale and patches within the home range to determine selection congruency and important habitat variables. In addition, we used linear models to determine if body size was related to selection patterns and strengths. Our results indicated habitat selection of adult male alligators was a scale-dependent process. Alligators demonstrated greater overall selection for habitat variables at the patch level and less at the home range level, suggesting resources may not be limited when selecting a home range for animals in our study area. Further, diurnal habitat selection patterns may depend on thermoregulatory needs. There was no relationship between resource selection or home range size and body size, suggesting size-dependent dominance hierarchies may not have influenced alligator resource selection or space use in our sample. Though apparent habitat suitability and low alligator density did not manifest in an observed dominance hierarchy, we hypothesize that a change in either could increase intraspecific interactions, facilitating a dominance hierarchy. Due to the broad and diverse ecological roles of alligators, understanding the factors that influence their social dominance

  20. Light enough to travel or wise enough to stay? Brain size evolution and migratory behavior in birds.

    PubMed

    Vincze, Orsolya

    2016-09-01

    Brain size relative to body size is smaller in migratory than in nonmigratory birds. Two mutually nonexclusive hypotheses had been proposed to explain this association. On the one hand, the "energetic trade-off hypothesis" claims that migratory species were selected to have smaller brains because of the interplay between neural tissue volume and migratory flight. On the other hand, the "behavioral flexibility hypothesis" argues that resident species are selected to have higher cognitive capacities, and therefore larger brains, to enable survival in harsh winters, or to deal with environmental seasonality. Here, I test the validity and setting of these two hypotheses using 1466 globally distributed bird species. First, I show that the negative association between migration distance and relative brain size is very robust across species and phylogeny. Second, I provide strong support for the energetic trade-off hypothesis, by showing the validity of the trade-off among long-distance migratory species alone. Third, using resident and short-distance migratory species, I demonstrate that environmental harshness is associated with enlarged relative brain size, therefore arguably better cognition. My study provides the strongest comparative support to date for both the energetic trade-off and the behavioral flexibility hypotheses, and highlights that both mechanisms contribute to brain size evolution, but on different ends of the migratory spectrum. PMID:27436482

  1. Adult Body Size, Hormone Receptor Status, and Premenopausal Breast Cancer Risk in a Multiethnic Population

    PubMed Central

    John, Esther M.; Sangaramoorthy, Meera; Phipps, Amanda I.; Koo, Jocelyn; Horn-Ross, Pamela L.

    2011-01-01

    Large body size has been associated with a reduced risk of premenopausal breast cancer in non-Hispanic white women. Data on other racial/ethnic populations are limited. The authors examined the association between premenopausal breast cancer risk and adult body size in 672 cases and 808 controls aged ≥35 years from a population-based case-control study conducted in 1995–2004 in the San Francisco Bay Area (Hispanics: 375 cases, 483 controls; African Americans: 154 cases, 160 controls; non-Hispanic whites: 143 cases, 165 controls). Multivariate adjusted odds ratios and 95% confidence intervals were calculated using unconditional logistic regression. Height was associated with increased breast cancer risk (highest vs. lowest quartile: odds ratio = 1.77, 95% confidence interval: 1.23, 2.53; Ptrend < 0.01); the association did not vary by hormone receptor status or race/ethnicity. Body mass index (measured as weight (kg) divided by height (m) squared) was inversely associated with risk in all 3 racial/ethnic groups, but only for estrogen receptor– and progesterone receptor–positive tumors (body mass index ≥30 vs. <25: odds ratio = 0.42; 95% confidence interval: 0.29, 0.61). Other body size measures (current weight, body build, adult weight gain, young adult weight and body mass index, waist circumference, and waist-to-height ratio) were similarly inversely associated with risk of estrogen receptor– and progesterone receptor–positive breast cancer but not estrogen receptor– and progesterone receptor–negative disease. Despite racial/ethnic differences in body size, inverse associations were similar across the 3 racial/ethnic groups when stratified by hormone receptor status. PMID:21084558

  2. Increasing body size among adult cook islanders between 1966 and 1996.

    PubMed

    Ulijaszek, S J

    2001-01-01

    There is limited evidence of a secular trend toward increased body size among populations in the Pacific Region, although some populations have shown a clear rise in overweight and obesity across the past 30 years or so. Mean height, weight and body mass index (BMI) of adults surveyed in 1996 on Rarotonga, the Cook Islands, are reported by age group and compared with data collected in 1966 by Evans and Prior, to determine the extent to which a secular trend in increasing body size has taken place across this 30-year period. In addition, a comparison of these anthropometric variables between subjects born on the most modernized island of Rarotonga with those born on other less-modernized islands is made, to determine the extent to which adult body size differs according to place of origin. Comparing the sample of those born on Rarotonga, the most modernized island, with those born on other, less modernized islands shows those born on Rarotonga to be taller, but not relatively heavier than those born elsewhere in the Cook Islands. Both males and females of the 1996 sample of adults are significantly taller, heavier, with higher BMI compared with the 1966 sample, indicating a secular trend toward increased body size across this 30-year period. The mean BMIs of the younger age groups in 1996 are greater than those of the same age groups in 1966, indicating a secular trend toward greater body fatness. There has been a significant increase in obesity among both males and females. In 1966, 14% of males had a BMI greater than 30, while in 1996, the proportion was 52%. Among females, 44% of those measured in 1966 had a BMI greater than 30, while in 1996 the proportion was 57%. The higher mean stature of younger adult males relative to older ones suggests that the secular trend toward increasing height may have been underway prior to 1966. The mean statures and weights of adults aged 60 years and older in the 1996 sample are more similar to values given for most age groups

  3. Resting state fMRI entropy probes complexity of brain activity in adults with ADHD.

    PubMed

    Sokunbi, Moses O; Fung, Wilson; Sawlani, Vijay; Choppin, Sabine; Linden, David E J; Thome, Johannes

    2013-12-30

    In patients with attention deficit hyperactivity disorder (ADHD), quantitative neuroimaging techniques have revealed abnormalities in various brain regions, including the frontal cortex, striatum, cerebellum, and occipital cortex. Nonlinear signal processing techniques such as sample entropy have been used to probe the regularity of brain magnetoencephalography signals in patients with ADHD. In the present study, we extend this technique to analyse the complex output patterns of the 4 dimensional resting state functional magnetic resonance imaging signals in adult patients with ADHD. After adjusting for the effect of age, we found whole brain entropy differences (P=0.002) between groups and negative correlation (r=-0.45) between symptom scores and mean whole brain entropy values, indicating lower complexity in patients. In the regional analysis, patients showed reduced entropy in frontal and occipital regions bilaterally and a significant negative correlation between the symptom scores and the entropy maps at a family-wise error corrected cluster level of P<0.05 (P=0.001, initial threshold). Our findings support the hypothesis of abnormal frontal-striatal-cerebellar circuits in ADHD and the suggestion that sample entropy is a useful tool in revealing abnormalities in the brain dynamics of patients with psychiatric disorders.

  4. Distinct Brain and Behavioral Benefits from Cognitive vs. Physical Training: A Randomized Trial in Aging Adults

    PubMed Central

    Chapman, Sandra B.; Aslan, Sina; Spence, Jeffrey S.; Keebler, Molly W.; DeFina, Laura F.; Didehbani, Nyaz; Perez, Alison M.; Lu, Hanzhang; D'Esposito, Mark

    2016-01-01

    Insidious declines in normal aging are well-established. Emerging evidence suggests that non-pharmacological interventions, specifically cognitive and physical training, may counter diminishing age-related cognitive and brain functions. This randomized trial compared effects of two training protocols: cognitive training (CT) vs. physical training (PT) on cognition and brain function in adults 56–75 years. Sedentary participants (N = 36) were randomized to either CT or PT group for 3 h/week over 12 weeks. They were assessed at baseline-, mid-, and post-training using neurocognitive, MRI, and physiological measures. The CT group improved on executive function whereas PT group's memory was enhanced. Uniquely deploying cerebral blood flow (CBF) and cerebral vascular reactivity (CVR) MRI, the CT cohort showed increased CBF within the prefrontal and middle/posterior cingulate cortex (PCC) without change to CVR compared to PT group. Improvements in complex abstraction were positively associated with increased resting CBF in dorsal anterior cingulate cortex (dACC). Exercisers with higher CBF in hippocampi bilaterally showed better immediate memory. The preliminary evidence indicates that increased cognitive and physical activity improves brain health in distinct ways. Reasoning training enhanced frontal networks shown to be integral to top-down cognitive control and brain resilience. Evidence of increased resting CBF without changes to CVR implicates increased neural health rather than improved vascular response. Exercise did not improve cerebrovascular response, although CBF increased in hippocampi of those with memory gains. Distinct benefits incentivize testing effectiveness of combined protocols to strengthen brain health. PMID:27462210

  5. Promoting brain health through exercise and diet in older adults: a physiological perspective.

    PubMed

    Jackson, Philippa A; Pialoux, Vincent; Corbett, Dale; Drogos, Lauren; Erickson, Kirk I; Eskes, Gail A; Poulin, Marc J

    2016-08-15

    The rise in incidence of age-related cognitive impairment is a global health concern. Ageing is associated with a number of changes in the brain that, collectively, contribute to the declines in cognitive function observed in older adults. Structurally, the ageing brain atrophies as white and grey matter volumes decrease. Oxidative stress and inflammation promote endothelial dysfunction thereby hampering cerebral perfusion and thus delivery of energy substrates and nutrients. Further, the development of amyloid plaques and neurofibrillary tangles contributes to neuronal loss. Of interest, there are substantial inter-individual differences in the degree to which these physical and functional changes impact upon cognitive function as we grow older. This review describes how engaging in physical activity and cognitive activities and adhering to a Mediterranean style diet promote 'brain health'. From a physiological perspective, we discuss the effects of these modifiable lifestyle behaviours on the brain, and how some recent human trials are beginning to show some promise as to the effectiveness of lifestyle behaviours in combating cognitive impairment. Moreover, we propose that these lifestyle behaviours, through numerous mechanisms, serve to increase brain, cerebrovascular and cognitive reserve, thereby preserving and enhancing cognitive function for longer.

  6. Distinct Brain and Behavioral Benefits from Cognitive vs. Physical Training: A Randomized Trial in Aging Adults.

    PubMed

    Chapman, Sandra B; Aslan, Sina; Spence, Jeffrey S; Keebler, Molly W; DeFina, Laura F; Didehbani, Nyaz; Perez, Alison M; Lu, Hanzhang; D'Esposito, Mark

    2016-01-01

    Insidious declines in normal aging are well-established. Emerging evidence suggests that non-pharmacological interventions, specifically cognitive and physical training, may counter diminishing age-related cognitive and brain functions. This randomized trial compared effects of two training protocols: cognitive training (CT) vs. physical training (PT) on cognition and brain function in adults 56-75 years. Sedentary participants (N = 36) were randomized to either CT or PT group for 3 h/week over 12 weeks. They were assessed at baseline-, mid-, and post-training using neurocognitive, MRI, and physiological measures. The CT group improved on executive function whereas PT group's memory was enhanced. Uniquely deploying cerebral blood flow (CBF) and cerebral vascular reactivity (CVR) MRI, the CT cohort showed increased CBF within the prefrontal and middle/posterior cingulate cortex (PCC) without change to CVR compared to PT group. Improvements in complex abstraction were positively associated with increased resting CBF in dorsal anterior cingulate cortex (dACC). Exercisers with higher CBF in hippocampi bilaterally showed better immediate memory. The preliminary evidence indicates that increased cognitive and physical activity improves brain health in distinct ways. Reasoning training enhanced frontal networks shown to be integral to top-down cognitive control and brain resilience. Evidence of increased resting CBF without changes to CVR implicates increased neural health rather than improved vascular response. Exercise did not improve cerebrovascular response, although CBF increased in hippocampi of those with memory gains. Distinct benefits incentivize testing effectiveness of combined protocols to strengthen brain health. PMID:27462210

  7. Promoting brain health through exercise and diet in older adults: a physiological perspective.

    PubMed

    Jackson, Philippa A; Pialoux, Vincent; Corbett, Dale; Drogos, Lauren; Erickson, Kirk I; Eskes, Gail A; Poulin, Marc J

    2016-08-15

    The rise in incidence of age-related cognitive impairment is a global health concern. Ageing is associated with a number of changes in the brain that, collectively, contribute to the declines in cognitive function observed in older adults. Structurally, the ageing brain atrophies as white and grey matter volumes decrease. Oxidative stress and inflammation promote endothelial dysfunction thereby hampering cerebral perfusion and thus delivery of energy substrates and nutrients. Further, the development of amyloid plaques and neurofibrillary tangles contributes to neuronal loss. Of interest, there are substantial inter-individual differences in the degree to which these physical and functional changes impact upon cognitive function as we grow older. This review describes how engaging in physical activity and cognitive activities and adhering to a Mediterranean style diet promote 'brain health'. From a physiological perspective, we discuss the effects of these modifiable lifestyle behaviours on the brain, and how some recent human trials are beginning to show some promise as to the effectiveness of lifestyle behaviours in combating cognitive impairment. Moreover, we propose that these lifestyle behaviours, through numerous mechanisms, serve to increase brain, cerebrovascular and cognitive reserve, thereby preserving and enhancing cognitive function for longer. PMID:27524792

  8. The sexual identity of adult intestinal stem cells controls organ size and plasticity.

    PubMed

    Hudry, Bruno; Khadayate, Sanjay; Miguel-Aliaga, Irene

    2016-02-18

    Sex differences in physiology and disease susceptibility are commonly attributed to developmental and/or hormonal factors, but there is increasing realization that cell-intrinsic mechanisms play important and persistent roles. Here we use the Drosophila melanogaster intestine to investigate the nature and importance of cellular sex in an adult somatic organ in vivo. We find that the adult intestinal epithelium is a cellular mosaic of different sex differentiation pathways, and displays extensive sex differences in expression of genes with roles in growth and metabolism. Cell-specific reversals of the sexual identity of adult intestinal stem cells uncovers the key role this identity has in controlling organ size, reproductive plasticity and response to genetically induced tumours. Unlike previous examples of sexually dimorphic somatic stem cell activity, the sex differences in intestinal stem cell behaviour arise from intrinsic mechanisms that control cell cycle duration and involve a new doublesex- and fruitless-independent branch of the sex differentiation pathway downstream of transformer. Together, our findings indicate that the plasticity of an adult somatic organ is reversibly controlled by its sexual identity, imparted by a new mechanism that may be active in more tissues than previously recognized. PMID:26887495

  9. The sexual identity of adult intestinal stem cells controls organ size and plasticity

    PubMed Central

    Hudry, Bruno; Khadayate, Sanjay; Miguel-Aliaga, Irene

    2016-01-01

    SUMMARY Sex differences in physiology and disease susceptibility are commonly attributed to developmental and/or hormonal factors, but there is increasing realisation that cell-intrinsic mechanisms play important and persistent roles1,2. Here we use the Drosophila melanogaster intestine to investigate the nature and significance of cellular sex in an adult somatic organ in vivo. We find that the adult intestinal epithelium is a cellular mosaic of different sex differentiation pathways, and displays extensive sex differences in expression of genes with roles in growth and metabolism. Cell-specific reversals of the sexual identity of adult intestinal stem cells uncover its key roles in controlling organ size, its reproductive plasticity and its response to genetically induced tumours. Unlike previous examples of sexually dimorphic somatic stem cell activity, the sex differences in intestinal stem cell behaviour arise from intrinsic mechanisms, which control cell cycle duration and involve a new doublesex- and fruitless-independent branch of the sex differentiation pathway downstream of transformer. Together, our findings indicate that the plasticity of an adult somatic organ is reversibly controlled by its sexual identity, imparted by a new mechanism that may be active in more tissues than previously recognised. PMID:26887495

  10. Brain activation during visual working memory correlates with behavioral mobility performance in older adults.

    PubMed

    Kawagoe, Toshikazu; Suzuki, Maki; Nishiguchi, Shu; Abe, Nobuhito; Otsuka, Yuki; Nakai, Ryusuke; Yamada, Minoru; Yoshikawa, Sakiko; Sekiyama, Kaoru

    2015-01-01

    Functional mobility and cognitive function often decline with age. We previously found that functional mobility as measured by the Timed Up and Go Test (TUG) was associated with cognitive performance for visually-encoded (i.e., for location and face) working memory (WM) in older adults. This suggests a common neural basis between TUG and visual WM. To elucidate this relationship further, the present study aimed to examine the neural basis for the WM-mobility association. In accordance with the well-known neural compensation model in aging, we hypothesized that "attentional" brain activation for easy WM would increase in participants with lower mobility. The data from 32 healthy older adults were analyzed, including brain activation during easy WM tasks via functional Magnetic Resonance Imaging (fMRI) and mobility performance via both TUG and a simple walking test. WM performance was significantly correlated with TUG but not with simple walking. Some prefrontal brain activations during WM were negatively correlated with TUG performance, while positive correlations were found in subcortical structures including the thalamus, putamen and cerebellum. Moreover, activation of the subcortical regions was significantly correlated with WM performance, with less activation for lower WM performers. These results indicate that older adults with lower mobility used more cortical (frontal) and fewer subcortical resources for easy WM tasks. To date, the frontal compensation has been proposed separately in the motor and cognitive domains, which have been assumed to compensate for dysfunction of the other brain areas; however, such dysfunction was less clear in previous studies. The present study observed such dysfunction as degraded activation associated with lower performance, which was found in the subcortical regions. We conclude that a common dysfunction-compensation activation pattern is likely the neural basis for the association between visual WM and functional mobility.

  11. Brain glucose metabolism in adults with ataxia-telangiectasia and their asymptomatic relatives.

    PubMed

    Volkow, Nora D; Tomasi, Dardo; Wang, Gene-Jack; Studentsova, Yana; Margus, Brad; Crawford, Thomas O

    2014-06-01

    Ataxia-telangiectasia is a recessive genetic disorder (ATM is the mutated gene) of childhood with severe motor impairments and whereas homozygotes manifest the disorder, heterozygotes are asymptomatic. Structural brain imaging and post-mortem studies in individuals with ataxia-telangiectasia have reported cerebellar atrophy; but abnormalities of motor control characteristic of extrapyramidal dysfunction suggest impairment of broader motor networks. Here, we investigated possible dysfunction in other brain areas in individuals with ataxia-telangiectasia and tested for brain changes in asymptomatic relatives to assess if heterozygocity affects brain function. We used positron emission tomography and (18)F-fluorodeoxyglucose to measure brain glucose metabolism (quantified as µmol/100 g/min), which serves as a marker of brain function, in 10 adults with ataxia-telangiectasia, 19 non-affected adult relatives (12 siblings, seven parents) and 29 age-matched healthy controls. Statistical parametric mapping and region of interest analyses were used to compare individuals with ataxia-telangiectasia, asymptomatic relatives, and unrelated controls. We found that participants with ataxia-telangiectasia had lower metabolism in cerebellar hemispheres (14%, P < 0.001), anterior vermis (40%, P < 0.001) and fusiform gyrus (20%, P < 0.001) compared with controls or siblings, and lower metabolism in hippocampus (12%, P = 0.05) compared with controls, and showed significant intersubject variability (decreases in vermis ranged from 18% to 60%). Participants with ataxia-telangiectasia also had higher metabolism in globus pallidus (16%, P = 0.05), which correlated negatively with motor performance. Asymptomatic relatives had lower metabolism in anterior vermis (12%; P = 0.01) and hippocampus (19%; P = 0.002) than controls. Our results indicate that, in addition to the expected decrease in cerebellar metabolism, participants with ataxia-telangiectasia had widespread changes in metabolic

  12. Brain glucose metabolism in adults with ataxia-telangiectasia and their asymptomatic relatives.

    PubMed

    Volkow, Nora D; Tomasi, Dardo; Wang, Gene-Jack; Studentsova, Yana; Margus, Brad; Crawford, Thomas O

    2014-06-01

    Ataxia-telangiectasia is a recessive genetic disorder (ATM is the mutated gene) of childhood with severe motor impairments and whereas homozygotes manifest the disorder, heterozygotes are asymptomatic. Structural brain imaging and post-mortem studies in individuals with ataxia-telangiectasia have reported cerebellar atrophy; but abnormalities of motor control characteristic of extrapyramidal dysfunction suggest impairment of broader motor networks. Here, we investigated possible dysfunction in other brain areas in individuals with ataxia-telangiectasia and tested for brain changes in asymptomatic relatives to assess if heterozygocity affects brain function. We used positron emission tomography and (18)F-fluorodeoxyglucose to measure brain glucose metabolism (quantified as µmol/100 g/min), which serves as a marker of brain function, in 10 adults with ataxia-telangiectasia, 19 non-affected adult relatives (12 siblings, seven parents) and 29 age-matched healthy controls. Statistical parametric mapping and region of interest analyses were used to compare individuals with ataxia-telangiectasia, asymptomatic relatives, and unrelated controls. We found that participants with ataxia-telangiectasia had lower metabolism in cerebellar hemispheres (14%, P < 0.001), anterior vermis (40%, P < 0.001) and fusiform gyrus (20%, P < 0.001) compared with controls or siblings, and lower metabolism in hippocampus (12%, P = 0.05) compared with controls, and showed significant intersubject variability (decreases in vermis ranged from 18% to 60%). Participants with ataxia-telangiectasia also had higher metabolism in globus pallidus (16%, P = 0.05), which correlated negatively with motor performance. Asymptomatic relatives had lower metabolism in anterior vermis (12%; P = 0.01) and hippocampus (19%; P = 0.002) than controls. Our results indicate that, in addition to the expected decrease in cerebellar metabolism, participants with ataxia-telangiectasia had widespread changes in metabolic

  13. Estimating total population size for adult female sea turtles: Accounting for non-nesters

    USGS Publications Warehouse

    Kendall, W.L.; Richardson, J.I.; Rees, Alan F.

    2008-01-01

    Assessment of population size and changes therein is important to sea turtle management and population or life history research. Investigators might be interested in testing hypotheses about the effect of current population size or density (number of animals per unit resource) on future population processes. Decision makers might want to determine a level of allowable take of individual turtles of specified life stage. Nevertheless, monitoring most stages of sea turtle life histories is difficult, because obtaining access to individuals is difficult. Although in-water assessments are becoming more common, nesting females and their hatchlings remain the most accessible life stages. In some cases adult females of a given nesting population are sufficiently philopatric that the population itself can be well defined. If a well designed tagging study is conducted on this population, survival, breeding probability, and the size of the nesting population in a given year can be estimated. However, with published statistical methodology the size of the entire breeding population (including those females skipping nesting in that year) cannot be estimated without assuming that each adult female in this population has the same probability of nesting in a given year (even those that had just nested in the previous year). We present a method for estimating the total size of a breeding population (including nesters those skipping nesting) from a tagging study limited to the nesting population, allowing for the probability of nesting in a given year to depend on an individual's nesting status in the previous year (i.e., a Markov process). From this we further develop estimators for rate of growth from year to year in both nesting population and total breeding population, and the proportion of the breeding population that is breeding in a given year. We also discuss assumptions and apply these methods to a breeding population of hawksbill sea turtles (Eretmochelys imbricata) from

  14. A meta-analysis of response inhibition and Stroop interference control deficits in adults with traumatic brain injury (TBI).

    PubMed

    Dimoska-Di Marco, Aneta; McDonald, Skye; Kelly, Michelle; Tate, Robyn; Johnstone, Stuart

    2011-04-01

    The prominent clinical feature of behavioral impulsivity following traumatic brain injury (TBI) suggests impairment of frontal inhibitory control processes. This meta-analysis consolidates the recent surge in studies across two forms of "effortful" inhibition, employing well-defined paradigms of response inhibition (N = 20; i.e., go/no-go, sustained attention to response, stop-signal, Conners' continuous performance tasks) and response interference control (N = 21, i.e., Stroop color word tasks). Across 41 effect sizes involving 989 adults with mild to severe TBI and 969 controls, the overall effect of TBI on reduced inhibitory control was small to moderate (d = 0.3) and significant. The effect was larger in studies measuring response inhibition performance (d = 0.5), while Stroop interference control yielded a nonsignificant overall effect size (d = 0.05). Further analysis of the latter finding revealed a large effect size when Stroop task studies used the outcome measure "total time on task" (d = 1.4), but not "RT per trial" or "number of stimuli" (d = -0.8 and -0.9). Response speed in these tasks was impaired to a large degree (d = 0.96). Together these findings support a response inhibition deficit following TBI but suggest factors other than interference control, such as poor processing speed, fatigue, and underarousal, may underlie poor performance in Stroop tasks.

  15. When Problem Size Matters: Differential Effects of Brain Stimulation on Arithmetic Problem Solving and Neural Oscillations

    PubMed Central

    Rütsche, Bruno; Hauser, Tobias U.; Jäncke, Lutz; Grabner, Roland H.

    2015-01-01

    The problem size effect is a well-established finding in arithmetic problem solving and is characterized by worse performance in problems with larger compared to smaller operand size. Solving small and large arithmetic problems has also been shown to involve different cognitive processes and distinct electroencephalography (EEG) oscillations over the left posterior parietal cortex (LPPC). In this study, we aimed to provide further evidence for these dissociations by using transcranial direct current stimulation (tDCS). Participants underwent anodal (30min, 1.5 mA, LPPC) and sham tDCS. After the stimulation, we recorded their neural activity using EEG while the participants solved small and large arithmetic problems. We found that the tDCS effects on performance and oscillatory activity critically depended on the problem size. While anodal tDCS improved response latencies in large arithmetic problems, it decreased solution rates in small arithmetic problems. Likewise, the lower-alpha desynchronization in large problems increased, whereas the theta synchronization in small problems decreased. These findings reveal that the LPPC is differentially involved in solving small and large arithmetic problems and demonstrate that the effects of brain stimulation strikingly differ depending on the involved neuro-cognitive processes. PMID:25789486

  16. The Role of Body Size in Mate Selection among African American Young Adults

    PubMed Central

    Simons, Leslie G.; Simons, Ronald L.

    2016-01-01

    A profusion of studies have demonstrated that body size is a major factor in mate selection for both men and women. The particular role played by weight, however, has been subject to some debate, particularly with respect to the types of body sizes deemed most attractive, and scholars have questioned the degree to which body size preferences are constant across groups. In this paper, we drew from two perspectives on this issue, Sexual Strategies Theory and what we termed the cultural variability perspective, and used survey data to examine how body size was associated with both casual dating and serious romantic relationships. We used a United States sample of 386 African American adolescents and young adults between ages 16 and 21, living in the Midwest and Southeast, and who were enrolled in either high school or college. Results showed that overweight women were more likely to report casually dating than women in the thinnest weight category. Body size was not related to dating status among men. Among women, the results suggest stronger support for the cultural variability argument than for Sexual Strategies Theory. Potential explanations for these findings are discussed. PMID:26973377

  17. Epigenetic Gene Regulation in the Adult Mammalian Brain: Multiple roles in Memory Formation

    PubMed Central

    Lubin, Farah D.

    2011-01-01

    Brain-derived neurotrophic factor (bdnf) is one of numerous gene products necessary for long-term memory formation and dysregulation of bdnf has been implicated in the pathogenesis of cognitive and mental disorders. Recent work indicates that epigenetic-regulatory mechanisms including the markings of histone proteins and associated DNA remain labile throughout the lifespan and represent an attractive molecular process contributing to gene regulation in the brain. In this review, important information will be discussed on epigenetics as a set of newly identified dynamic transcriptional mechanisms serving to regulate gene expression changes in the adult brain with particular emphasis on bdnf transcriptional readout in learning and memory formation. This review will also highlight evidence for the role of epigenetics in aberrant bdnf gene regulation in the pathogenesis of cognitive dysfunction associated with seizure disorders, Rett syndrome, Schizophrenia, and Alzheimer’s disease. Such research offers novel concepts for understanding epigenetic transcriptional mechanisms subserving adult cognition and mental health, and furthermore promises novel avenues for therapeutic approach in the clinic. PMID:21419233

  18. Acquisition of Visual Perception in Blind Adults Using the BrainPort Artificial Vision Device

    PubMed Central

    Pintar, Christine; Arnoldussen, Aimee; Fisher, Christopher

    2015-01-01

    OBJECTIVE. We sought to determine whether intensive low vision rehabilitation would confer any functional improvement in a sample of blind adults using the BrainPort artificial vision device. METHOD. Eighteen adults ages 28–69 yr (n = 10 men and n = 8 women) who had light perception only or worse vision bilaterally spent up to 6 hr per day for 1 wk undergoing structured rehabilitation interventions. The functional outcomes of object identification and word recognition were tested at baseline and after rehabilitation training. RESULTS. At baseline, participants were unable to complete the two functional assessments. After participation in the 1-wk training protocol, participants were able to use the BrainPort device to complete the two tasks with moderate success. CONCLUSION. Without training, participants were not able to perform above chance level using the BrainPort device. As artificial vision technologies become available, occupational therapy practitioners can play a key role in clients’ success or failure in using these devices. PMID:25553750

  19. Antenatal Maternal Stress Alters Functional Brain Responses In Adult Offspring During Conditioned Fear

    PubMed Central

    Sadler, Theodore R.; Nguyen, Peter T.; Yang, Jun; Givrad, Tina K.; Mayer, Emeran A.; Maarek, Jean-Michel I.; Hinton, David R.; Holschneider, Daniel P.

    2011-01-01

    Antenatal maternal stress has been shown in rodent models and in humans to result in altered behavioral and neuroendocrine responses, yet little is known about its effects on functional brain activation. Pregnant female rats received a daily foot-shock stress or sham-stress two days after testing plug-positive and continuing for the duration of their pregnancy. Adult male offspring (age 14 weeks) with and without prior maternal stress (MS) were exposed to an auditory fear conditioning (CF) paradigm. Cerebral blood flow (CBF) was assessed during recall of the tone cue in the nonsedated, nontethered animal using the 14C-iodoantipyrine method, in which the tracer was administered intravenously by remote activation of an implantable minipump. Regional CBF distribution was examined by autoradiography and analyzed by statistical parametric mapping in the three-dimensionally reconstructed brains. Presence of fear memory was confirmed by behavioral immobility (‘freezing’). Corticosterone plasma levels during the CF paradigm were measured by ELISA in a separate group of rats. Antenatal MS exposure altered functional brain responses to the fear conditioned cue in adult offspring. Rats with prior MS exposure compared to those without demonstrated heightened fear responsivity, exaggerated and prolonged corticosterone release, increased functional cerebral activation of limbic/paralimbic regions (amygdala, ventral hippocampus, insula, ventral striatum, nucleus acumbens), the locus coeruleus, and white matter, and deactivation of medial prefrontal cortical regions. Dysregulation of corticolimbic circuits may represent risk factors in the future development of anxiety disorders and associated alterations in emotional regulation. PMID:21300034

  20. Aging-Dependent Changes in the Radiation Response of the Adult Rat Brain

    SciTech Connect

    Schindler, Matthew K. Forbes, M. Elizabeth; Robbins, Mike E.; Riddle, David R.

    2008-03-01

    Purpose: To assess the impact of aging on the radiation response in the adult rat brain. Methods and Materials: Male rats 8, 18, or 28 months of age received a single 10-Gy dose of whole-brain irradiation (WBI). The hippocampal dentate gyrus was analyzed 1 and 10 weeks later for sensitive neurobiologic markers associated with radiation-induced damage: changes in density of proliferating cells, immature neurons, total microglia, and activated microglia. Results: A significant decrease in basal levels of proliferating cells and immature neurons and increased microglial activation occurred with normal aging. The WBI induced a transient increase in proliferation that was greater in older animals. This proliferation response did not increase the number of immature neurons, which decreased after WBI in young rats, but not in old rats. Total microglial numbers decreased after WBI at all ages, but microglial activation increased markedly, particularly in older animals. Conclusions: Age is an important factor to consider when investigating the radiation response of the brain. In contrast to young adults, older rats show no sustained decrease in number of immature neurons after WBI, but have a greater inflammatory response. The latter may have an enhanced role in the development of radiation-induced cognitive dysfunction in older individuals.

  1. The association of brain structure with gait velocity in older adults: a quantitative volumetric analysis of brain MRI

    PubMed Central

    Katz, Mindy J.; Lipton, Michael L.; Lipton, Richard B.; Verghese, Joe

    2015-01-01

    Introduction While cortical processes play an important role in controlling locomotion, the underlying structural brain changes associated with slowing of gait in aging are not yet fully established. Our study aimed to examine the relationship between cortical gray matter volume (GM), white matter volume (WM), ventricular volume (VV), hippocampal and hippocampal subfield volumes, and gait velocity in older adults free of dementia. Methods Gait and cognitive performance was tested in 112 community-residing adults, age 70 years and over, participating in the Einstein Aging Study. Gait velocity (cm/s) was obtained using an instrumented walkway. Volumetric MRI measures were estimated using a FreeSurfer software. We examined the cross-sectional relationship of GM, WM, VV, and hippocampal total and subfield volumes and gait velocity using linear regression models. In complementary models, the effect of memory performance on the relationship between gait velocity and regional volumes was evaluated. Results Slower gait velocity was associated with smaller cortical GM and total hippocampal volumes. There was no association between gait velocity and WM or VV. Among hippocampal subfields, only smaller presubiculum volume was significantly associated with decrease in gait velocity. Addition of the memory performance to the models attenuated the association between gait velocity and all volumetric measures. Conclusions Our findings indicate that total GM and hippocampal volumes as well as specific hippocampal subfield volumes are inversely associated with locomotor function. These associations are probably affected by cognitive status of study population. PMID:25921321

  2. Stroop-like interference in the real animal size test and the pictorial animal size test in 5- to 12-year-old children and young adults.

    PubMed

    Ikeda, Yoshifumi; Okuzumi, Hideyuki; Kokubun, Mitsuru

    2014-01-01

    This study examined prepotent response inhibition among 653 5- to 12-year-old children and young adults divided into five age groups: forty-six 5- to 6-year-olds, one hundred fifty-eight 7- to 8-year-olds, one hundred ninety-six 9- to 10-year-olds, one hundred eighty-three 11- to 12-year-olds, and 70 young adults (19- to 22-year-olds). Two paper-and-pencil versions of Stroop-like tasks were administered: the Real Animal Size Test and the Pictorial Animal Size Test. In these tests, participants are presented with pictures of animals (large animals such as an elephant, a giraffe, and a whale vs. small animals such as a frog, a bird, and a squirrel) printed as either big or small images that are mismatched with the animal's real size. Participants are required to decide the size of the animals (big vs. small) based on either the size in real life or the size of the picture. The results indicated the following: (a) The Pictorial Animal Size Test elicited robust interference, whereas the Real Animal Size Test elicited no interference; (b) prepotent response inhibition develops markedly in childhood and between children and young adults; and (c) error correction increased rapidly after age 8. The mechanism of interference and the influence of metacognition on prepotent response inhibition are discussed. PMID:24716870

  3. Homo erectus and Middle Pleistocene hominins: brain size, skull form, and species recognition.

    PubMed

    Rightmire, G Philip

    2013-09-01

    Hominins that differ from Homo erectus, the Neanderthals, and recent humans are known from Middle Pleistocene localities across the Old World. The taxonomic status of these populations has been clouded by controversy. Perhaps the most critical problem has been an incomplete understanding of variation in skull form. Here, both H. erectus and later mid-Pleistocene hominins are the focus of an investigation aimed at clarifying the relationships among brain volume, basicranial dimensions, neurocranial shape, and certain facial characters. Brain size in H. erectus averages about 950 cm(3), while in a series of Middle Pleistocene crania from Africa and Europe, volume is about 1230 cm(3). If encephalization is the primary mechanism operating in the mid-Pleistocene, then diverse aspects of cranial form cannot all be treated as independent variables. Correlation is utilized to examine the associations among measurements for more than 30 H. erectus crania that are reasonably well preserved. A similar approach is used with the Middle Pleistocene sample. Patterns of covariation are compared in order to assess integration. Next, factor analysis is applied to the H. erectus specimens in an attempt to identify modules, tightly integrated traits that can evolve independently. Studies of the variation within H. erectus are followed by direct comparisons with the Middle Pleistocene population. Discriminant functions facilitate the description of intergroup differences. Traits that vary independently from brain volume include anterior frontal broadening, lateral expansion of the parietal vault, elevation of the lambda-inion chord, and rounding of the sagittal contour of the occipital. This finding helps to resolve the problem of species recognition. Neurocranial proportions as well as characters from the cranial base and face can be incorporated into a differential diagnosis for the mid-Pleistocene sample. Evidence presented here supports arguments for speciation in the Middle

  4. Mice with ablated adult brain neurogenesis are not impaired in antidepressant response to chronic fluoxetine.

    PubMed

    Jedynak, Paulina; Kos, Tomasz; Sandi, Carmen; Kaczmarek, Leszek; Filipkowski, Robert K

    2014-09-01

    The neurogenesis hypothesis of major depression has two main facets. One states that the illness results from decreased neurogenesis while the other claims that the very functioning of antidepressants depends on increased neurogenesis. In order to verify the latter, we have used cyclin D2 knockout mice (cD2 KO mice), known to have virtually no adult brain neurogenesis, and we demonstrate that these mice successfully respond to chronic fluoxetine. After unpredictable chronic mild stress, mutant mice showed depression-like behavior in forced swim test, which was eliminated with chronic fluoxetine treatment, despite its lack of impact on adult hippocampal neurogenesis in cD2 KO mice. Our results suggest that new neurons are not indispensable for the action of antidepressants such as fluoxetine. Using forced swim test and tail suspension test, we also did not observe depression-like behavior in control cD2 KO mice, which argues against the link between decreased adult brain neurogenesis and major depression.

  5. Organization of the histaminergic system in adult zebrafish (Danio rerio) brain: neuron number, location, and cotransmitters.

    PubMed

    Sundvik, Maria; Panula, Pertti

    2012-12-01

    Histamine is an essential factor in the ascending arousal system (AAS) during motivated behaviors. Histamine and hypocretin/orexin (hcrt) are proposed to be responsible for different aspects of arousal and wakefulness, histamine mainly for cognitive and motivated behaviors. In this study we visualized the entire histaminergic neuron population in adult male and female zebrafish brain and quantified the histaminergic neuron numbers. There were 40-45 histaminergic neurons in both male and female zebrafish brain. Further, we identified cotransmitters of histaminergic neurons in the ventrocaudal hypothalamus, i.e., around the posterior recess (PR) in adult zebrafish. Galanin, γ-aminobutyric acid (GABA), and thyrotropin-releasing hormone (TRH) were colocalized with histamine in some but not all neurons, a result that was verified by intracerebroventricular injections of colchicine into adult zebrafish. Fibers immunoreactive (ir) for galanin, GABA, TRH, or methionine-enkephalin (mENK) were dense in the ventrocaudal hypothalamus around the histaminergic neurons. In histamine-ir fibers TRH and galanin immunoreactivities were also detected in the ventral telencephalon. All these neurotransmitters are involved in maintaining the equilibrium of the sleep-wake state. Our results are in accordance with results from rats, further supporting the use of zebrafish as a tool to study molecular mechanisms underlying complex behaviors.

  6. Traumatic Brain Injury among Older Adults at Level I and II Trauma Centers

    PubMed Central

    Cuthbert, Jeffrey P.; Whyte, John; Corrigan, John D.; Faul, Mark; Harrison-Felix, Cynthia

    2013-01-01

    Abstract Individuals 65 years of age and over have the highest rates of traumatic brain injury (TBI)-related hospitalizations and deaths, and older adults (defined variably across studies) have particularly poor outcomes after TBI. The factors predicting these outcomes remain poorly understood, and age-specific care guidelines for TBI do not exist. This study provides an overview of TBI in older adults using data from the National Trauma Data Bank (NTDB) gathered between 2007 and 2010, evaluates age group-specific trends in rates of TBI over time using U.S. Census data, and examines whether routinely collected information is able to predict hospital discharge status among older adults with TBI in the NTDB. Results showed a 20–25% increase in trauma center admissions for TBI among the oldest age groups (those >=75 years), relative to the general population, between 2007 and 2010. Older adults (>=65 years) with TBI tended to be white females who have incurred an injury from a fall resulting in a “severe” Abbreviated Injury Scale (AIS) score of the head. Older adults had more in-hospital procedures, such as neuroimaging and neurosurgery, tended to experience longer hospital stays, and were more likely to require continued medical care than younger adults. Older age, injury severity, and hypotension increased the odds of in-hospital death. The public health burden of TBI among older adults will likely increase as the Baby Boom generation ages. Improved primary and secondary prevention of TBI in this cohort is needed. PMID:23962046

  7. Cognitive functioning in relation to brain amyloid-β in healthy adults with Down syndrome.

    PubMed

    Hartley, Sigan L; Handen, Benjamin L; Devenny, Darlynne A; Hardison, Regina; Mihaila, Iulia; Price, Julie C; Cohen, Annie D; Klunk, William E; Mailick, Marsha R; Johnson, Sterling C; Christian, Bradley T

    2014-09-01

    Nearly all adults with Down syndrome show neuropathology of Alzheimer's disease, including amyloid-β deposition, by their fifth decade of life. In the current study, we examined the association between brain amyloid-β deposition, assessed via in vivo assessments of neocortical Pittsburgh compound B, and scores on an extensive neuropsychological battery of measures of cognitive functioning in 63 adults (31 male, 32 female) with Down syndrome aged 30-53 years who did not exhibit symptoms of dementia. Twenty-two of the adults with Down syndrome were identified as having elevated neocortical Pittsburgh compound B retention levels. There was a significant positive correlation (r = 0.62, P < 0.0001) between age and neocortical Pittsburgh compound B retention. This robust association makes it difficult to discriminate normative age-related decline in cognitive functioning from any potential effects of amyloid-β deposition. When controlling for chronological age in addition to mental age, there were no significant differences between the adults with Down syndrome who had elevated neocortical Pittsburgh compound B retention levels and those who did not on any of the neuropsychological measures. Similarly, when examining Pittsburgh compound B as a continuous variable, after controlling for mental age and chronological age, only the Rivermead Picture Recognition score was significantly negatively associated with neocortical Pittsburgh compound B retention. Our findings indicate that many adults with Down syndrome can tolerate amyloid-β deposition without deleterious effects on cognitive functioning. However, we may have obscured true effects of amyloid-β deposition by controlling for chronological age in our analyses. Moreover, our sample included adults with Down syndrome who were most 'resistant' to the effects of amyloid-β deposition, as adults already exhibiting clinical symptoms of dementia symptoms were excluded from the study.

  8. Apparent target size of rat brain benzodiazepine receptor, acetylcholinesterase, and pyruvate kinase is highly influenced by experimental conditions

    SciTech Connect

    Nielsen, M.; Braestrup, C.

    1988-08-25

    Radiation inactivation is a method to determine the apparent target size of molecules. In this report we examined whether radiation inactivation of various enzymes and brain receptors is influenced by the preparation of samples preceding irradiation. The apparent target sizes of endogenous acetylcholinesterase and pyruvate kinase from rat brain and from rabbit muscle and benzodiazepine receptor from rat brain were investigated in some detail. In addition the target sizes of alcohol dehydrogenase (from yeast and horse liver), beta-galactosidase (from Escherichia coli), lactate dehydrogenase (endogenous from rat brain), and 5-HT2 receptors, acetylcholine muscarine receptors, and (/sup 35/S) butyl bicyclophosphorothionate tertiary binding sites from rat brain were determined. The results show that apparent target sizes are highly influenced by the procedure applied for sample preparation before irradiation. The data indicate that irradiation of frozen whole tissue as opposed to lyophilized tissue or frozen tissue homogenates will estimate the smallest and most relevant functional target size of a receptor or an enzyme.

  9. Increased brain size in mammals is associated with size variations in gene families with cell signalling, chemotaxis and immune-related functions.

    PubMed

    Castillo-Morales, Atahualpa; Monzón-Sandoval, Jimena; Urrutia, Araxi O; Gutiérrez, Humberto

    2014-01-22

    Genomic determinants underlying increased encephalization across mammalian lineages are unknown. Whole genome comparisons have revealed large and frequent changes in the size of gene families, and it has been proposed that these variations could play a major role in shaping morphological and physiological differences among species. Using a genome-wide comparative approach, we examined changes in gene family size (GFS) and degree of encephalization in 39 fully sequenced mammalian species and found a significant over-representation of GFS variations in line with increased encephalization in mammals. We found that this relationship is not accounted for by known correlates of brain size such as maximum lifespan or body size and is not explained by phylogenetic relatedness. Genes involved in chemotaxis, immune regulation and cell signalling-related functions are significantly over-represented among those gene families most highly correlated with encephalization. Genes within these families are prominently expressed in the human brain, particularly the cortex, and organized in co-expression modules that display distinct temporal patterns of expression in the developing cortex. Our results suggest that changes in GFS associated with encephalization represent an evolutionary response to the specific functional requirements underlying increased brain size in mammals.

  10. Free radical scavenger, edaravone, reduces the lesion size of lacunar infarction in human brain ischemic stroke

    PubMed Central

    2011-01-01

    Background Although free radicals have been reported to play a role in the expansion of ischemic brain lesions, the effect of free radical scavengers is still under debate. In this study, the temporal profile of ischemic stroke lesion sizes was assessed for more than one year to evaluate the effect of edaravone which might reduce ischemic damage. Methods We sequentially enrolled acute ischemic stroke patients, who admitted between April 2003 and March 2004, into the edaravone(-) group (n = 83) and, who admitted between April 2004 and March 2005, into the edaravone(+) group (n = 93). Because, edaravone has been used as the standard treatment after April 2004 in our hospital. To assess the temporal profile of the stroke lesion size, the ratio of the area [T2-weighted magnetic resonance images (T2WI)/iffusion-weighted magnetic resonance images (DWI)] were calculated. Observations on T2WI were continued beyond one year, and observational times were classified into subacute (1-2 months after the onset), early chronic (3-6 month), late chronic (7-12 months) and old (≥13 months) stages. Neurological deficits were assessed by the National Institutes of Health Stroke Scale upon admission and at discharge and by the modified Rankin Scale at 1 year following stroke onset. Results Stroke lesion size was significantly attenuated in the edaravone(+) group compared with the edaravone(-) group in the period of early and late chronic observational stages. However, this reduction in lesion size was significant within a year and only for the small-vessel occlusion stroke patients treated with edaravone. Moreover, patients with small-vessel occlusion strokes that were treated with edaravone showed significant neurological improvement during their hospital stay, although there were no significant differences in outcome one year after the stroke. Conclusion Edaravone treatment reduced the volume of the infarct and improved neurological deficits during the subacute period, especially

  11. Aging Effects on Whole-Brain Functional Connectivity in Adults Free of Cognitive and Psychiatric Disorders.

    PubMed

    Ferreira, Luiz Kobuti; Regina, Ana Carolina Brocanello; Kovacevic, Natasa; Martin, Maria da Graça Morais; Santos, Pedro Paim; Carneiro, Camila de Godoi; Kerr, Daniel Shikanai; Amaro, Edson; McIntosh, Anthony Randal; Busatto, Geraldo F

    2016-09-01

    Aging is associated with decreased resting-state functional connectivity (RSFC) within the default mode network (DMN), but most functional imaging studies have restricted the analysis to specific brain regions or networks, a strategy not appropriate to describe system-wide changes. Moreover, few investigations have employed operational psychiatric interviewing procedures to select participants; this is an important limitation since mental disorders are prevalent and underdiagnosed and can be associated with RSFC abnormalities. In this study, resting-state fMRI was acquired from 59 adults free of cognitive and psychiatric disorders according to standardized criteria and based on extensive neuropsychological and clinical assessments. We tested for associations between age and whole-brain RSFC using Partial Least Squares, a multivariate technique. We found that normal aging is not only characterized by decreased RSFC within the DMN but also by ubiquitous increases in internetwork positive correlations and focal internetwork losses of anticorrelations (involving mainly connections between the DMN and the attentional networks). Our results reinforce the notion that the aging brain undergoes a dedifferentiation processes with loss of functional diversity. These findings advance the characterization of healthy aging effects on RSFC and highlight the importance of adopting a broad, system-wide perspective to analyze brain connectivity.

  12. Reduced Cerebral Oxygen Content in the DG and SVZ In Situ Promotes Neurogenesis in the Adult Rat Brain In Vivo.

    PubMed

    Zhang, Kuan; Zhou, Yanzhao; Zhao, Tong; Wu, Liying; Huang, Xin; Wu, Kuiwu; Xu, Lun; Li, Dahu; Liu, Shuhong; Zhao, Yongqi; Fan, Ming; Zhu, Lingling

    2015-01-01

    Neurogenesis in the adult brain occurs mainly within two neurogenic structures, the dentate gyrus (DG) of the hippocampus and the sub-ventricular zone (SVZ) of the forebrain. It has been reported that mild hypoxia promoted the proliferation of Neural Stem Cells (NSCs)in vitro. Our previous study further demonstrated that an external hypoxic environment stimulated neurogenesis in the adult rat brain in vivo. However, it remains unknown how external hypoxic environments affect the oxygen content in the brain and result in neurogenesis. Here we use an optical fiber luminescent oxygen sensor to detect the oxygen content in the adult rat brain in situ under normoxia and hypoxia. We found that the distribution of oxygen in cerebral regions is spatiotemporally heterogeneous. The Po2 values in the ventricles (45∼50 Torr) and DG (approximately 10 Torr) were much higher than those of other parts of the brain, such as the cortex and thalamus (approximately 2 Torr). Interestingly, our in vivo studies showed that an external hypoxic environment could change the intrinsic oxygen content in brain tissues, notably reducing oxygen levels in both the DG and SVZ, the major sites of adult neurogenesis. Furthermore, the hypoxic environment also increased the expression of HIF-1α and VEGF, two factors that have been reported to regulate neurogenesis, within the DG and SVZ. Thus, we have demonstrated that reducing the oxygen content of the external environment decreased Po2 levels in the DG and SVZ. This reduced oxygen level in the DG and SVZ might be the main mechanism triggering neurogenesis in the adult brain. More importantly, we speculate that varying oxygen levels may be the physiological basis of the regionally restricted neurogenesis in the adult brain.

  13. Beyond utterances: distributed cognition as a framework for studying discourse in adults with acquired brain injury.

    PubMed

    Duff, Melissa C; Mutlu, Bilge; Byom, Lindsey; Turkstra, Lyn S

    2012-02-01

    Considerable effort has been directed at understanding the nature of the communicative deficits observed in individuals with acquired brain injuries. Yet several theoretical, methodological, and clinical challenges remain. In this article, we examine distributed cognition as a framework for understanding interaction among communication partners, interaction of communication and cognition, and interaction with the environments and contexts of everyday language use. We review the basic principles of distributed cognition and the implications for applying this approach to the study of discourse in individuals with cognitive-communication disorders. We also review a range of protocols and findings from our research that highlight how the distributed cognition approach might offer a deeper understanding of communicative mechanisms and deficits in individuals with cognitive communication impairments. The advantages and implications of distributed cognition as a framework for studying discourse in adults with acquired brain injury are discussed. PMID:22362323

  14. Beyond Utterances: Distributed Cognition as a Framework for Studying Discourse in Adults with Acquired Brain Injury

    PubMed Central

    Duff, Melissa C.; Mutlu, Bilge; Byom, Lindsey; Turkstra, Lyn S.

    2014-01-01

    Considerable effort has been directed at understanding the nature of the communicative deficits observed in individuals with acquired brain injuries. Yet several theoretical, methodological, and clinical challenges remain. In this article, we examine distributed cognition as a framework for understanding interaction among communication partners, interaction of communication and cognition, and interaction with the environments and contexts of everyday language use. We review the basic principles of distributed cognition and the implications for applying this approach to the study of discourse in individuals with cognitive-communication disorders. We also review a range of protocols and findings from our research that highlight how the distributed cognition approach might offer a deeper understanding of communicative mechanisms and deficits in individuals with cognitive communication impairments. The advantages and implications of distributed cognition as a framework for studying discourse in adults with acquired brain injury are discussed. PMID:22362323

  15. Adult axolotls can regenerate original neuronal diversity in response to brain injury.

    PubMed

    Amamoto, Ryoji; Huerta, Violeta Gisselle Lopez; Takahashi, Emi; Dai, Guangping; Grant, Aaron K; Fu, Zhanyan; Arlotta, Paola

    2016-01-01

    The axolotl can regenerate multiple organs, including the brain. It remains, however, unclear whether neuronal diversity, intricate tissue architecture, and axonal connectivity can be regenerated; yet, this is critical for recovery of function and a central aim of cell replacement strategies in the mammalian central nervous system. Here, we demonstrate that, upon mechanical injury to the adult pallium, axolotls can regenerate several of the populations of neurons present before injury. Notably, regenerated neurons acquire functional electrophysiological traits and respond appropriately to afferent inputs. Despite the ability to regenerate specific, molecularly-defined neuronal subtypes, we also uncovered previously unappreciated limitations by showing that newborn neurons organize within altered tissue architecture and fail to re-establish the long-distance axonal tracts and circuit physiology present before injury. The data provide a direct demonstration that diverse, electrophysiologically functional neurons can be regenerated in axolotls, but challenge prior assumptions of functional brain repair in regenerative species. PMID:27156560

  16. Cellular distribution and localisation of iron in adult rat brain ( substantia nigra)

    NASA Astrophysics Data System (ADS)

    Meinecke, Ch.; Morawski, M.; Reinert, T.; Arendt, T.; Butz, T.

    2006-08-01

    Iron appears to be one of the main factors in the metal induced neurodegeneration. Quantitative information on cellular, sub-cellular and cell specific distributions of iron is therefore important to assess. The investigations reported here were carried out on a brain from an adult rat. Therefore, 6 μm thick embedded, unstained brain sections containing the midbrain (substantia nigra, SN) were analysed. Particle induced X-ray emission (PIXE) using a focussed proton beam (beam - diameter app. 1 μm) was performed to determine the quantitative iron content on a cellular and sub-cellular level. The integral analysis shows that the iron content in the SN pars reticulata is twice as high than in the SN pars compacta. The analysis of the iron content on the cellular level revealed no remarkable differences between glia cells and neurons. This is in contrast to other studies using staining techniques.

  17. The long-term side effects of radiation therapy for benign brain tumors in adults.

    PubMed

    al-Mefty, O; Kersh, J E; Routh, A; Smith, R R

    1990-10-01

    Radiation therapy plays an integral part in managing intracranial tumors. While the risk:benefit ratio is considered acceptable for treating malignant tumors, risks of long-term complications of radiotherapy need thorough assessment in adults treated for benign tumors. Many previously reported delayed complications of radiotherapy can be attributed to inappropriate treatment or to the sensitivity of a developing child's brain to radiation. Medical records, radiological studies, autopsy findings, and follow-up information were reviewed for 58 adult patients (31 men and 27 women) treated between 1958 and 1987 with radiotherapy for benign intracranial tumors. Patient ages at the time of irradiation ranged from 21 to 87 years (mean 47.7 years). The pathology included 46 pituitary adenomas, five meningiomas, four glomus jugulare tumors, two pineal area tumors, and one craniopharyngioma. Average radiation dosage was 4984 cGy (range 3100 to 7012 cGy), given in an average of 27.2 fractions (range 15 to 45 fractions), over a period averaging 46.6 days. The follow-up period ranged from 3 to 31 years (mean 8.1 years). Findings related to tumor recurrence or surgery were excluded. Twenty-two patients had complications considered to be delayed side effects of radiotherapy. Two patients had visual deterioration developing 3 and 6 years after treatment; six had pituitary dysfunction; and 17 had varying degrees of parenchymal changes of the brain, occurring mostly in the temporal lobes and relating to the frequent presentation of pituitary tumors (two of these also had pituitary dysfunction). One clival tumor with the radiographic appearance of a meningioma, developed 30 years post-irradiation for acromegaly. This study unveils considerable delayed sequelae of radiotherapy in a series of adult patients receiving what is considered "safe" treatment for benign brain tumors.

  18. The long-term side effects of radiation therapy for benign brain tumors in adults

    SciTech Connect

    al-Mefty, O.; Kersh, J.E.; Routh, A.; Smith, R.R. )

    1990-10-01

    Radiation therapy plays an integral part in managing intracranial tumors. While the risk:benefit ratio is considered acceptable for treating malignant tumors, risks of long-term complications of radiotherapy need thorough assessment in adults treated for benign tumors. Many previously reported delayed complications of radiotherapy can be attributed to inappropriate treatment or to the sensitivity of a developing child's brain to radiation. Medical records, radiological studies, autopsy findings, and follow-up information were reviewed for 58 adult patients (31 men and 27 women) treated between 1958 and 1987 with radiotherapy for benign intracranial tumors. Patient ages at the time of irradiation ranged from 21 to 87 years (mean 47.7 years). The pathology included 46 pituitary adenomas, five meningiomas, four glomus jugulare tumors, two pineal area tumors, and one craniopharyngioma. Average radiation dosage was 4984 cGy (range 3100 to 7012 cGy), given in an average of 27.2 fractions (range 15 to 45 fractions), over a period averaging 46.6 days. The follow-up period ranged from 3 to 31 years (mean 8.1 years). Findings related to tumor recurrence or surgery were excluded. Twenty-two patients had complications considered to be delayed side effects of radiotherapy. Two patients had visual deterioration developing 3 and 6 years after treatment; six had pituitary dysfunction; and 17 had varying degrees of parenchymal changes of the brain, occurring mostly in the temporal lobes and relating to the frequent presentation of pituitary tumors. One clival tumor with the radiographic appearance of a meningioma, developed 30 years post-irradiation for acromegaly. This study unveils considerable delayed sequelae of radiotherapy in a series of adult patients receiving what is considered safe treatment for benign brain tumors. 163 refs.

  19. Occupational and environmental risk factors of adult primary brain cancers: a systematic review.

    PubMed

    Gomes, J; Al Zayadi, A; Guzman, A

    2011-04-01

    The incidence of brain neoplasm has been progressively increasing in recent years in the industrialized countries. One of the reasons for this increased incidence could be better access to health care and improved diagnosis in the industrialized countries. It also appears that Caucasians have a higher incidence than blacks or Hispanics or Asians. A number of risk factors have been identified and described including the genetic, ethnic and age-based factors. Certain occupational and environmental factors are also believed to influence the risk of primary adult brain tumors. Potential occupational and environmental factors include exposure to diagnostic and therapeutic radiations, electromagnetic radiation from cellular phones and other wireless devices, infectious agents, air pollution and residence near landfills and high-voltage power lines and jobs as firefighters, farmers, physician, chemists and jobs in industries such as petrochemical, power generation, synthetic rubber manufacturing, agricultural chemicals manufacturing. The purpose of this systematic review is to examine occupational and environmental risk factors of brain neoplasm. A range of occupational and environmental exposures are evaluated for significance of their relationship with adult primary brain tumors. On the basis of this review we suggest a concurrent evaluation of multiple risk factors both within and beyond occupational and environmental domains. The concurrent approach needs to consider better exposure assessment techniques, lifetime occupational exposures, genotypic and phenotypic characteristics and lifestyle and dietary habits. This approach needs to be interdisciplinary with contributions from neurologists, oncologists, epidemiologists and molecular biologists. Conclusive evidence that has eluded multitude of studies with single focus and single exposure needs to multifaceted and multidisciplinary. PMID:23022824

  20. Gestational ketogenic diet programs brain structure and susceptibility to depression & anxiety in the adult mouse offspring

    PubMed Central

    Sussman, Dafna; Germann, Jurgen; Henkelman, Mark

    2015-01-01

    Introduction The ketogenic diet (KD) has seen an increase in popularity for clinical and non-clinical purposes, leading to rise in concern about the diet's impact on following generations. The KD is known to have a neurological effect, suggesting that exposure to it during prenatal brain development may alter neuro-anatomy. Studies have also indicated that the KD has an anti-depressant effect on the consumer. However, it is unclear whether any neuro-anatomical and/or behavioral changes would occur in the offspring and persist into adulthood. Methods To fill this knowledge gap we assessed the brain morphology and behavior of 8-week-old young-adult CD-1 mice, who were exposed to the KD in utero, and were fed only a standard-diet (SD) in postnatal life. Standardized neuro-behavior tests included the Open-Field, Forced-Swim, and Exercise Wheel tests, and were followed by post-mortem Magnetic Resonance Imaging (MRI) to assess brain anatomy. Results The adult KD offspring exhibit reduced susceptibility to anxiety and depression, and elevated physical activity level when compared with controls exposed to the SD both in utero and postnatally. Many neuro-anatomical differences exist between the KD offspring and controls, including, for example, a cerebellar volumetric enlargement by 4.8%, a hypothalamic reduction by 1.39%, and a corpus callosum reduction by 4.77%, as computed relative to total brain volume. Conclusions These results suggest that prenatal exposure to the KD programs the offspring neuro-anatomy and influences their behavior in adulthood. PMID:25642385

  1. Hippotherapy in Adult Patients with Chronic Brain Disorders: A Pilot Study

    PubMed Central

    Sunwoo, Hyuk; Kwon, Jeong-Yi; Kim, Tae-Won; Lee, Ji-Young; Kim, Yun-Hee

    2012-01-01

    Objective To investigate the effects of hippotherapy for adult patients with brain disorders. Method Eight chronic brain disorder patients (7 males, mean age 42.4±16.6 years) were recruited. The mean duration from injury was 7.9±7.7 years. The diagnoses were stroke (n=5), traumatic brain disorder (n=2), and cerebral palsy (n=1). Hippotherapy sessions were conducted twice a week for eight consecutive weeks in an indoor riding arena. Each hippotherapy session lasted 30 minutes. All participants were evaluated by the Berg balance scale, Tinetti Performance-Oriented Mobility Assessment, 10 Meter Walking Test, Functional Ambulatory Category, Korean Beck Depression Inventory, and Hamilton Depression Rating Scale. We performed baseline assessments twice just before starting hippotherapy. We also assessed the participants immediately after hippotherapy and at eight weeks after hippotherapy. Results All participants showed no difference in balance, gait function, and emotion between the two baseline assessments before hippotherapy. During the eight-week hippotherapy program, all participants showed neither adverse effects nor any accidents; all had good compliance. After hippotherapy, there were significant improvements in balance and gait speed in comparison with the baseline assessment (p<0.05), and these effects were sustained for two months after hippotherapy. However, there was no significant difference in emotion after hippotherapy. Conclusion We could observe hippotherapy to be a safe and effective alternative therapy for adult patients with brain disorders in improving balance and gait function. Further future studies are warranted to delineate the benefits of hippotherapy on chronic stroke patients. PMID:23342306

  2. EBIC-guidelines for management of severe head injury in adults. European Brain Injury Consortium.

    PubMed

    Maas, A I; Dearden, M; Teasdale, G M; Braakman, R; Cohadon, F; Iannotti, F; Karimi, A; Lapierre, F; Murray, G; Ohman, J; Persson, L; Servadei, F; Stocchetti, N; Unterberg, A

    1997-01-01

    Guidelines for the management of severe head injury in adults as evolved by the European Brain Injury Consortium are presented and discussed. The importance of preventing and treating secondary insults is emphasized and the principles on which treatment is based are reviewed. Guidelines presented are of a pragmatic nature, based on consensus and expert opinion, covering the treatment from accident site to intensive care unit. Specific aspects pertaining to the conduct of clinical trials in head injury are highlighted. The adopted approach is further discussed in relation to other approaches to the development of guidelines, such as evidence based analysis.

  3. Leptin replacement alters brain response to food cues in genetically leptin-deficient adults

    PubMed Central

    Baicy, Kate; London, Edythe D.; Monterosso, John; Wong, Ma-Li; Delibasi, Tuncay; Sharma, Anil; Licinio, Julio

    2007-01-01

    A missense mutation in the ob gene causes leptin deficiency and morbid obesity. Leptin replacement to three adults with this mutation normalized body weight and eating behavior. Because the neural circuits mediating these changes were unknown, we paired functional magnetic resonance imaging (fMRI) with presentation of food cues to these subjects. During viewing of food-related stimuli, leptin replacement reduced brain activation in regions linked to hunger (insula, parietal and temporal cortex) while enhancing activation in regions linked to inhibition and satiety (prefrontal cortex). Leptin appears to modulate feeding behavior through these circuits, suggesting therapeutic targets for human obesity. PMID:17986612

  4. Memory reorganization in adult brain: observations in three patients with temporal lobe epilepsy.

    PubMed

    Gleissner, Ulrike; Helmstaedter, Christoph; Elger, Christian Erich

    2002-02-01

    We present three patients with left-sided temporal lobe epilepsy who exhibited preoperatively a neuropsychological pattern characteristic for interhemispheric language transfer (marked nonverbal memory deficits, relatively preserved verbal memory and language performance). The Wada test indicated atypical language dominance in two patients, but one patient was clearly left hemispheric language dominant. All patients showed a marked recovery of nonverbal memory after left-sided surgery. Results are discussed with respect to memory transfer and plasticity for memory functions in the adult brain. PMID:11904242

  5. The relationship between organ dose and patient size in tube current modulated adult thoracic CT scans

    NASA Astrophysics Data System (ADS)

    Khatonabadi, Maryam; Zhang, Di; Yang, Jeffrey; DeMarco, John J.; Cagnon, Chris C.; McNitt-Gray, Michael F.

    2012-03-01

    Recently published AAPM Task Group 204 developed conversion coefficients that use scanner reported CTDIvol to estimate dose to the center of patient undergoing fixed tube current body exam. However, most performed CT exams use TCM to reduce dose to patients. Therefore, the purpose of this study was to investigate the correlation between organ dose and a variety of patient size metrics in adult chest CT scans that use tube current modulation (TCM). Monte Carlo simulations were performed for 32 voxelized models with contoured lungs and glandular breasts tissue, consisting of females and males. These simulations made use of patient's actual TCM data to estimate organ dose. Using image data, different size metrics were calculated, these measurements were all performed on one slice, at the level of patient's nipple. Estimated doses were normalized by scanner-reported CTDIvol and plotted versus different metrics. CTDIvol values were plotted versus different metrics to look at scanner's output versus size. The metrics performed similarly in terms of correlating with organ dose. Looking at each gender separately, for male models normalized lung dose showed a better linear correlation (r2=0.91) with effective diameter, while female models showed higher correlation (r2=0.59) with the anterior-posterior measurement. There was essentially no correlation observed between size and CTDIvol-normalized breast dose. However, a linear relationship was observed between absolute breast dose and size. Dose to lungs and breasts were consistently higher in females with similar size as males which could be due to shape and composition differences between genders in the thoracic region.

  6. Age-related decreased inhibitory vs. excitatory gene expression in the adult autistic brain

    PubMed Central

    van de Lagemaat, Louie N.; Nijhof, Bonnie; Bosch, Daniëlle G. M.; Kohansal-Nodehi, Mahdokht; Keerthikumar, Shivakumar; Heimel, J. Alexander

    2014-01-01

    Autism spectrum disorders (ASDs) are neurodevelopmental disorders characterized by impaired social interaction and communication, and restricted behavior and interests. A disruption in the balance of excitatory and inhibitory neurotransmission has been hypothesized to underlie these disorders. Here we demonstrate that genes of both pathways are affected by ASD, and that gene expression of inhibitory and excitatory genes is altered in the cerebral cortex of adult but not younger autistic individuals. We have developed a measure for the difference in the level of excitation and inhibition based on gene expression and observe that in this measure inhibition is decreased relative to excitation in adult ASD compared to control. This difference was undetectable in young autistic brains. Given that many psychiatric features of autism are already present at an early age, this suggests that the observed imbalance in gene expression is an aging phenomenon in ASD rather than its underlying cause. PMID:25538548

  7. Effects of alcohol consumption on cognition and regional brain volumes among older adults.

    PubMed

    Downer, Brian; Jiang, Yang; Zanjani, Faika; Fardo, David

    2015-06-01

    This study utilized data from the Framingham Heart Study Offspring Cohort to examine the relationship between midlife and late-life alcohol consumption, cognitive functioning, and regional brain volumes among older adults without dementia or a history of abusing alcohol. The results from multiple linear regression models indicate that late life, but not midlife, alcohol consumption status is associated with episodic memory and hippocampal volume. Compared to late life abstainers, moderate consumers had larger hippocampal volume, and light consumers had higher episodic memory. The differences in episodic memory according to late life alcohol consumption status were no longer significant when hippocampal volume was included in the regression model. The findings from this study provide new evidence that hippocampal volume may contribute to the observed differences in episodic memory among older adults and late life alcohol consumption status.

  8. Abstracting meaning from complex information (gist reasoning) in adult traumatic brain injury.

    PubMed

    Vas, Asha Kuppachi; Spence, Jeffrey; Chapman, Sandra Bond

    2015-01-01

    Gist reasoning (abstracting meaning from complex information) was compared between adults with moderate-to-severe traumatic brain injury (TBI, n = 30) at least one year post injury and healthy adults (n = 40). The study also examined the contribution of executive functions (working memory, inhibition, and switching) and memory (immediate recall and memory for facts) to gist reasoning. The correspondence between gist reasoning and daily function was also examined in the TBI group. Results indicated that the TBI group performed significantly lower than the control group on gist reasoning, even after adjusting for executive functions and memory. Executive function composite was positively associated with gist reasoning (p < .001). Additionally, performance on gist reasoning significantly predicted daily function in the TBI group beyond the predictive ability of executive function alone (p = .011). Synthesizing and abstracting meaning(s) from information (i.e., gist reasoning) could provide an informative index into higher order cognition and daily functionality. PMID:25633568

  9. Behavioral responses to and brain distribution of morphine in mature adult and aged mice

    SciTech Connect

    Burton, C.K.; Ho, I.K.; Hoskins, B.

    1986-03-01

    Mature adult (3-6 mo old) and aged (2 yr old) male ICR mice were injected with 10 to 100 mg/kg morphine, s.c. The ED50 values for running behavior (as measured using Stoelting activity monitors and having each mouse serve as its own control) representing 5 times control activity was approximately 7.5 mg/kg for aged mice and approximately 17.5 mg/kg for the mature adults. The ED50 values for analgesia 1 hr after morphine administration using the tail-flick method (max. response time = 8 sec) were approx. 70 mg/kg for the aged mice and 15 mg/kg for the mature adults. One hour after injecting /sup 3/H-morphine at doses of 30 and 100 mg/kg, 0.13 and 0.14% of the doses appeared in brains of aged and mature adult mice, respectively. Regional distribution of the morphine was the same for both age groups. Expressed as percent of total brain morphine, it was as follows: cortex, 30%; midbrain, 18%; cerebellum, 17%; medulla, 12%; pons, 9%; striatum, 8% and periaqueductal gray, 6%. Expressed as g morphine/g tissue for the 2 doses, the distribution was; periaqueductal gray, 30 and 80; striatum, 9 and 34; medulla, 6 and 20 pons; 5 and 19; cerebellum, 4 and 13; midbrain 2.5 and 8.5 and cortex, 2 and 8. These results suggest that the differences in response to morphine by the two age groups were due to age-related differences in opioid receptor populations and/or affinities.

  10. Enhanced Z-LDA for Small Sample Size Training in Brain-Computer Interface Systems

    PubMed Central

    Gao, Dongrui; Zhang, Rui; Liu, Tiejun; Li, Fali; Ma, Teng; Lv, Xulin; Li, Peiyang; Yao, Dezhong; Xu, Peng

    2015-01-01

    Background. Usually the training set of online brain-computer interface (BCI) experiment is small. For the small training set, it lacks enough information to deeply train the classifier, resulting in the poor classification performance during online testing. Methods. In this paper, on the basis of Z-LDA, we further calculate the classification probability of Z-LDA and then use it to select the reliable samples from the testing set to enlarge the training set, aiming to mine the additional information from testing set to adjust the biased classification boundary obtained from the small training set. The proposed approach is an extension of previous Z-LDA and is named enhanced Z-LDA (EZ-LDA). Results. We evaluated the classification performance of LDA, Z-LDA, and EZ-LDA on simulation and real BCI datasets with different sizes of training samples, and classification results showed EZ-LDA achieved the best classification performance. Conclusions. EZ-LDA is promising to deal with the small sample size training problem usually existing in online BCI system. PMID:26550023

  11. On the relationship between cellular and hemodynamic properties of the human brain cortex throughout adult lifespan.

    PubMed

    Zhao, Yue; Wen, Jie; Cross, Anne H; Yablonskiy, Dmitriy A

    2016-06-01

    Establishing baseline MRI biomarkers for normal brain aging is significant and valuable for separating normal changes in the brain structure and function from different neurological diseases. In this paper for the first time we have simultaneously measured a variety of tissue specific contributions defining R2* relaxation of the gradient recalled echo (GRE) MRI signal in human brains of healthy adults (ages 22 to 74years) and related these measurements to tissue structural and functional properties. This was accomplished by separating tissue (R2t(⁎)) and extravascular BOLD contributions to the total tissue specific GRE MRI signal decay (R2(⁎)) using an advanced version of previously developed Gradient Echo Plural Contrast Imaging (GEPCI) approach and the acquisition and post-processing methods that allowed the minimization of artifacts related to macroscopic magnetic field inhomogeneities, and physiological fluctuations. Our data (20 healthy subjects) show that in most cortical regions R2t(⁎) increases with age while tissue hemodynamic parameters, i.e. relative oxygen extraction fraction (OEFrel), deoxygenated cerebral blood volume (dCBV) and tissue concentration of deoxyhemoglobin (Cdeoxy) remain practically constant. We also found the important correlations characterizing the relationships between brain structural and hemodynamic properties in different brain regions. Specifically, thicker cortical regions have lower R2t(⁎) and these regions have lower OEF. The comparison between GEPCI-derived tissue specific structural and functional metrics and literature information suggests that (a) regions in a brain characterized by higher R2t(⁎) contain higher concentration of neurons with less developed cellular processes (dendrites, spines, etc.), (b) regions in a brain characterized by lower R2t(⁎) represent regions with lower concentration of neurons but more developed cellular processes, and (c) the age-related increases in the cortical R2t(⁎) mostly

  12. A detailed viscoelastic characterization of the P17 and adult rat brain.

    PubMed

    Elkin, Benjamin S; Ilankovan, Ashok I; Morrison, Barclay

    2011-11-01

    Brain is a morphologically and mechanically heterogeneous organ. Although rat brain is commonly used as an experimental neurophysiological model for various in vivo biomechanical studies, little is known about its regional viscoelastic properties. To address this issue, we have generated viscoelastic mechanical property data for specific anatomical regions of the P17 and adult rat brain. These ages are commonly used in rat experimental models. We measured mechanical properties of both white and gray matter regions in coronal slices with a custom-designed microindentation device performing stress-relaxation indentations to 10% effective strain. Shear moduli calculated for short (100?ms), intermediate (1?sec), and long (20?sec) time points, ranged from ?1?kPa for short term moduli to ?0.4?kPa for long term moduli. Both age and anatomic region were significant factors affecting the time-dependent shear modulus. White matter regions and regions of the cerebellum were much more compliant than those of the hippocampus, cortex, and thalamus. Linear viscoelastic models (Prony series, continuous phase lag, and a power law model) were fit to the time-dependent shear modulus data. All models fit the data equally with no significant differences between them (F-test; p>0.05). The F-test was also used to statistically determine that a Prony series with three time-dependent parameters accurately fit the data with no added benefit from additional terms. The age- and region-dependent rat brain viscoelastic properties presented here will help inform future biomechanical models of the rat brain with specific and accurate regional mechanical property data. PMID:21341982

  13. Brain

    MedlinePlus

    ... will return after updating. Resources Archived Modules Updates Brain Cerebrum The cerebrum is the part of the ... the outside of the brain and spinal cord. Brain Stem The brain stem is the part of ...

  14. Molecular size of benzodiazepine receptor in rat brain in situ: evidence for a functional dimer?

    NASA Astrophysics Data System (ADS)

    Doble, A.; Iversen, L. L.

    1982-02-01

    Benzodiazepine tranquillizers such as diazepam and chlordiazepoxide interact with high-affinity binding sites in nervous tissue1,2. The correlation between the affinities of various benzodiazepines for these sites with their clinical potencies and activity in behavioural and electrophysiological tests in animals suggests that the sites represent the functional `receptor' whereby benzodiazepines exert their effects3. The intimate involvement of benzodiazepines with γ-aminobutyric acid (GABA) and chloride channels raised the possibility that the benzodiazepine binding site (BDZ-R) may be a protein in the GABA receptor-effector complex4,5. GABA agonists enhance the affinity of BDZ-R for benzodiazepines6, although BDZ-R is distinct from the GABA receptor itself3. However, electrophysiological evidence suggests that the action of benzodiazepines is chloride channel, rather than receptor, directed7-10. Several attempts have been made to measure the molecular weight (Mr) of BDZ-R after solubilization from brain membranes: treatment with 1% Triton X-100 followed by assay of binding activity in solute fractions separated according to molecular weight suggested11 a value of ~200,000, photoaffinity labelling of BDZ-R with 3H-flunitrazepam (3H-FNZ) followed by more rigorous solubilization and gel chromatography indicated12,13 an apparent Mr of ~55,000 and a third approach14 a value of ~100,000. The measured molecular weight seems to depend critically on the solubilization procedure used. Chang et al.15 recently described the use of radiation inactivation to determine the size of BDZ-R in situ in calf brain membranes, and estimated a Mr, of 216,000. We have also used this approach; the results reported here indicate a Mr of between 90,000 and 100,000, but this is reduced to 60,000-63,000 in membranes pretreated with GABA, suggesting the disaggregation of a normally dimeric form.

  15. Ribosomal protein L11 is related to brain maturation during the adult phase in Apis cerana cerana (Hymenoptera, Apidae)

    NASA Astrophysics Data System (ADS)

    Meng, Fei; Lu, Wenjing; Yu, Feifei; Kang, Mingjiang; Guo, Xingqi; Xu, Baohua

    2012-05-01

    Ribosomal proteins (RPs) play pivotal roles in developmental regulation. The loss or mutation of ribosomal protein L11 ( RPL11) induces various developmental defects. However, few RPs have been functionally characterized in Apis cerana cerana. In this study, we isolated a single copy gene, AccRPL11, and characterized its connection to brain maturation. AccRPL11 expression was highly concentrated in the adult brain and was significantly induced by abiotic stresses such as pesticides and heavy metals. Immunofluorescence assays demonstrated that AccRPL11 was localized to the medulla, lobula and surrounding tissues of esophagus in the brain. The post-transcriptional knockdown of AccRPL11 gene expression resulted in a severe decrease in adult brain than in other tissues. The expression levels of other brain development-related genes, p38, ERK2, CacyBP and CREB, were also reduced. Immunofluorescence signal attenuation was also observed in AccRPL11-rich regions of the brain in ds AccRPL11-injected honeybees. Taken together, these results suggest that AccRPL11 may be functional in brain maturation in honeybee adults.

  16. Effect size of memory deficits in mice with adult-onset P301L tau expression.

    PubMed

    Hunsberger, Holly C; Rudy, Carolyn C; Weitzner, Daniel S; Zhang, Chong; Tosto, David E; Knowlan, Kevin; Xu, Ying; Reed, Miranda N

    2014-10-01

    Transgenic mice expressing mutations in tau have yielded essential discoveries for Alzheimer's disease. One of the most commonly used tau mouse models is the tet-off Tg(tauP301L)4510 model that expresses P301L human tau driven by the calcium-calmodulin kinase IIα (CaMKIIα) promoter system. Tau expression in this model is regulatable, allowing for suppression of mutant tau expression until adulthood and prevention of possible developmental alterations resulting from P301L tau expression during development. Here, we compared the effect and sample sizes needed for three learning and memory tasks in mice with adult-onset P301L tau expression. Our findings indicate that the Incremental Repeated Acquisition (IRA) and trace fear conditioning tasks, neither of which have previously been published with these mice, were highly sensitive to P301L tau expression, whereas the Morris water maze, the most commonly used task with this model, was the least sensitive. Memory deficits were observed at a time when tau pathology was subtle and prior to readily detectable neuronal loss. Thus, we provide essential information (effect and sample sizes needed) for establishing experimental designs at a time point when memory deficits are likely to go undetected if inadequate sample sizes are used. Our work also suggests the tet-off Tg4510 model provides a way to avoid mutant tau expression during the perinatal and early postnatal stages, thereby preventing possible developmental alterations unrelated to Alzheimer's disease.

  17. Landscape Simplification Constrains Adult Size in a Native Ground-Nesting Bee

    PubMed Central

    Renauld, Miles; Hutchinson, Alena; Loeb, Gregory; Poveda, Katja; Connelly, Heather

    2016-01-01

    Bees provide critical pollination services to 87% of angiosperm plants; however, the reliability of these services may become threatened as bee populations decline. Agricultural intensification, resulting in the simplification of environments at the landscape scale, greatly changes the quality and quantity of resources available for female bees to provision their offspring. These changes may alter or constrain the tradeoffs in maternal investment allocation between offspring size, number and sex required to maximize fitness. Here we investigate the relationship between landscape scale agricultural intensification and the size and number of individuals within a wild ground nesting bee species, Andrena nasonii. We show that agricultural intensification at the landscape scale was associated with a reduction in the average size of field collected A. nasonii adults in highly agricultural landscapes but not with the number of individuals collected. Small females carried significantly smaller (40%) pollen loads than large females, which is likely to have consequences for subsequent offspring production and fitness. Thus, landscape simplification is likely to constrain allocation of resources to offspring through a reduction in the overall quantity, quality and distribution of resources. PMID:26943127

  18. Relationships among vocabulary size, nonverbal cognition, and spoken word recognition in adults with cochlear implants

    NASA Astrophysics Data System (ADS)

    Collison, Elizabeth A.; Munson, Benjamin; Carney, Arlene E.

    2002-05-01

    Recent research has attempted to identify the factors that predict speech perception performance among users of cochlear implants (CIs). Studies have found that approximately 20%-60% of the variance in speech perception scores can be accounted for by factors including duration of deafness, etiology, type of device, and length of implant use, leaving approximately 50% of the variance unaccounted for. The current study examines the extent to which vocabulary size and nonverbal cognitive ability predict CI listeners' spoken word recognition. Fifteen postlingually deafened adults with nucleus or clarion CIs were given standardized assessments of nonverbal cognitive ability and expressive vocabulary size: the Expressive Vocabulary Test, the Test of Nonverbal Intelligence-III, and the Woodcock-Johnson-III Test of Cognitive Ability, Verbal Comprehension subtest. Two spoken word recognition tasks were administered. In the first, listeners identified isophonemic CVC words. In the second, listeners identified gated words varying in lexical frequency and neighborhood density. Analyses will examine the influence of lexical frequency and neighborhood density on the uniqueness point in the gating task, as well as relationships among nonverbal cognitive ability, vocabulary size, and the two spoken word recognition measures. [Work supported by NIH Grant P01 DC00110 and by the Lions 3M Hearing Foundation.

  19. Expression pattern of STOP lacZ reporter gene in adult and developing mouse brain.

    PubMed

    Couégnas, Alice; Schweitzer, Annie; Andrieux, Annie; Ghandour, M Said; Boehm, Nelly

    2007-05-15

    Stable tubulin-only polypeptide (STOP) proteins are microtubule-associated proteins responsible for microtubule stabilization in neurons. STOP null mice show apparently normal cerebral anatomy but display synaptic defects associated with neuroleptic-sensitive behavioral disorders. STOP null mice have therefore been proposed as an animal model for the study of schizophrenia. In the present study, the expression pattern of STOP gene in developing and adult brain has been examined by using lacZ gene inserted in the STOP locus, as a reporter gene. beta-Galactosidase (beta-gal) immunostaining was confined to neuronal cells and projections. Strong labeling was observed in the whole olfactory system, cortical layer VII, hippocampus, hypothalamus, cerebellum, habenula, fasciculus retroflexus, and interpeduncular nucleus in adults. Additionally, ventral thalamic nucleus, clusters of positive cells in striatum, and Cajal-Retzius cells of cortical layer I were labeled in young mice. The strong expression of STOP lacZ reporter gene observed in brain is confined to areas that may be involved in the schizophrenia-related symptoms observed in STOP-deficient mice.

  20. Neurotoxic Methamphetamine Doses Increase LINE-1 Expression in the Neurogenic Zones of the Adult Rat Brain

    PubMed Central

    Moszczynska, Anna; Flack, Amanda; Qiu, Ping; Muotri, Alysson R.; Killinger, Bryan A.

    2015-01-01

    Methamphetamine (METH) is a widely abused psychostimulant with the potential to cause neurotoxicity in the striatum and hippocampus. Several epigenetic changes have been described after administration of METH; however, there are no data regarding the effects of METH on the activity of transposable elements in the adult brain. The present study demonstrates that systemic administration of neurotoxic METH doses increases the activity of Long INterspersed Element (LINE-1) in two neurogenic niches in the adult rat brain in a promoter hypomethylation-independent manner. Our study also demonstrates that neurotoxic METH triggers persistent decreases in LINE-1 expression and increases the LINE-1 levels within genomic DNA in the striatum and dentate gyrus of the hippocampus, and that METH triggers LINE-1 retrotransposition in vitro. We also present indirect evidence for the involvement of glutamate (GLU) in LINE-1 activation. The results suggest that LINE-1 activation might occur in neurogenic areas in human METH users and might contribute to METH abuse-induced hippocampus-dependent memory deficits and impaired performance on several cognitive tasks mediated by the striatum. PMID:26463126

  1. Effective factors on linguistic disorder during acute phase following traumatic brain injury in adults.

    PubMed

    Chabok, Shahrokh Yousefzadeh; Kapourchali, Sara Ramezani; Leili, Ehsan Kazemnezhad; Saberi, Alia; Mohtasham-Amiri, Zahra

    2012-06-01

    Traumatic brain injury (TBI) has been known to be the leading cause of breakdown and long-term disability in people under 45 years of age. This study highlights the effective factors on post-traumatic (PT) linguistic disorder and relations between linguistic and cognitive function after trauma in adults with acute TBI. A cross-sectional design was employed to study 60 post-TBI hospitalized adults aged 18-65 years. Post-traumatic (PT) linguistic disorder and cognitive deficit after TBI were respectively diagnosed using the Persian Aphasia Test (PAT) and Persian version of Mini-Mental State Examination (MMSE) at discharge. Primary post-resuscitation consciousness level was determined using the Glasgow Coma Scale (GCS). Paracilinical data was obtained by CT scan technique. Multiple logistic regression analysis illustrated that brain injury severity was the first powerful significant predictor of PT linguistic disorder after TBI and frontotemporal lesion was the second. It was also revealed that cognitive function score was significantly correlated with score of each language skill except repetition. Subsequences of TBI are more commonly language dysfunctions that demand cognitive flexibility. Moderate, severe and fronto-temporal lesion can increase the risk of processing deficit in linguistic macrostructure production and comprehension. The dissociation risk of cortical and subcortical pathways related to cognitive-linguistic processing due to intracranial lesions can augment possibility of lexical-semantic processing deficit in acute phase which probably contributes to later cognitive-communication disorder.

  2. Neurotoxic Methamphetamine Doses Increase LINE-1 Expression in the Neurogenic Zones of the Adult Rat Brain.

    PubMed

    Moszczynska, Anna; Flack, Amanda; Qiu, Ping; Muotri, Alysson R; Killinger, Bryan A

    2015-10-14

    Methamphetamine (METH) is a widely abused psychostimulant with the potential to cause neurotoxicity in the striatum and hippocampus. Several epigenetic changes have been described after administration of METH; however, there are no data regarding the effects of METH on the activity of transposable elements in the adult brain. The present study demonstrates that systemic administration of neurotoxic METH doses increases the activity of Long INterspersed Element (LINE-1) in two neurogenic niches in the adult rat brain in a promoter hypomethylation-independent manner. Our study also demonstrates that neurotoxic METH triggers persistent decreases in LINE-1 expression and increases the LINE-1 levels within genomic DNA in the striatum and dentate gyrus of the hippocampus, and that METH triggers LINE-1 retrotransposition in vitro. We also present indirect evidence for the involvement of glutamate (GLU) in LINE-1 activation. The results suggest that LINE-1 activation might occur in neurogenic areas in human METH users and might contribute to METH abuse-induced hippocampus-dependent memory deficits and impaired performance on several cognitive tasks mediated by the striatum.

  3. Intraventricular brain-derived neurotrophic factor reduces infarct size after focal cerebral ischemia in rats.

    PubMed

    Schäbitz, W R; Schwab, S; Spranger, M; Hacke, W

    1997-05-01

    Brain-derived neurotrophic factor (BDNF), acting through the high-affinity receptor tyrosine kinase (TrkB), is widely distributed throughout the central nervous system and displays in vitro trophic effects on a wide range of neuronal cells, including hippocampal, cerebellar, and cortical neurons. In vivo, BDNF rescues motorneurons, hippocampal, and substantia nigral dopaminergic cells from traumatic and toxic brain injury. After transient middle cerebral artery occlusion (MCAO), upregulation of BDNF-mRNA in cortical neurons suggests that BDNF potentially plays a neuroprotective role in focal cerebral ischemia. In the current study, BDNF (2.1 micrograms/d) in vehicle or vehicle alone (controls) was delivered intraventricularly for 8 days, beginning 24 hours before permanent middle cerebral artery occlusion by intraluminal suture in Wistar rats (n = 13 per group). There were no differences in physiological variables recorded during surgery for the two groups. Neurological deficit (0 to 4 scale), which was assessed on a daily basis, improved in BDNF-treated animals compared with controls (P < 0.05; analysis of variance and Scheffe's test). There were no significant differences in weight in BDNF-treated animals and controls during the experiment. After elective killing on day 7 after MCAO, brains underwent 2,3,5-triphenyltetrazolium chloride staining for calculation of the infarct volume and for histology (hematoxylin and eosin and glial fibrillary acid protein). The mean total infarct volume was 83.1 +/- 27.1 mm3 in BDNF-treated animals and 139.2 +/- 56.4 mm3 in controls (mean +/- SD; P < 0.01, unpaired, two-tailed t-test). The cortical infarct volume was 10.8 +/- 7.1 mm3 in BDNF-treated animals and 37.9 +/- 19.8 mm3 in controls (mean +/- SD; P < 0.05; unpaired, two-tailed t-test), whereas ischemic lesion volume in caudoputaminal infarction was not significantly different. These results show that pretreatment with intraventricular BDNF reduces infarct size after focal

  4. Socioeconomic status, body size and physical activity of adults on Rarotonga, the Cook Islands.

    PubMed

    Ulijaszek, S J

    2001-01-01

    Much of the secular trend toward increased body size among populations in the Pacific Region has been attributed to the processes of economic modernization and socioeconomic change. The primary objective of the present analysis was to examine the relationships between socioeconomic factors and stature, weight, body mass index and physical activity level of adult Cook Islanders living a largely modernized lifestyle in the Pacific Region. In a cross-sectional study of physical activity, body size and socioeconomic status, a volunteer sample of 345 Cook Islanders aged 20-65 years was obtained from the total adult population of Rarotonga, and measured at six out-patient clinics. Stature, weight, body mass index (BMI), physical activity level and age were calculated by sex and occupational category, years of education, island of birth and number of years lived on Rarotonga, respectively, using SPSSPC for Windows. Stepwise multiple regression was used to examine the relationships between stature, weight, BMI, PALweekday (a measure of physical activity level), age and non-linear functions of age, and the socioeconomic variables. These analyses indicate that the secular trend in stature is a function of the relative level of modernization on Rarotonga relative to other Cook Islands, and with level of education. These factors associate differently among males and females, the secular trend among males appearing to be a general phenomenon in response to lifestyle change associated with life on Rarotonga, while among females the trend is a function of lifestyle change associated with education and independent of island of origin. The trend toward increasing body fatness is also different for males and females. Weight declines with age for both men and women, in a linear way for the males, but in a non-linear fashion for the females. Body weight is also greater among those males in more skilled and professional occupations than among those with less-skilled professions. For

  5. Meet the parents? Family size and the geographic proximity between adult children and older mothers in Sweden.

    PubMed

    Holmlund, Helena; Rainer, Helmut; Siedler, Thomas

    2013-06-01

    The aim of this study is to estimate the causal effect of family size on the proximity between older mothers and adult children by using a large administrative data set from Sweden. Our main results show that adult children in Sweden are not constrained by sibship size in choosing where to live: for families with more than one child, sibship size does not affect child-mother proximity. For aging parents, however, having fewer children reduces the probability of having at least one child living nearby, which is likely to have consequences for the intensity of intergenerational contact and eldercare.

  6. ERK phosphorylation in intact, adult brain by alpha(2)-adrenergic transactivation of EGF receptors.

    PubMed

    Du, Ting; Li, Baoman; Liu, Shufang; Zang, Peizhuo; Prevot, Vincent; Hertz, Leif; Peng, Liang

    2009-12-01

    Our previous work demonstrated dexmedetomidine-activated phosphorylation of extracellular regulated kinases 1 and 2 (ERK(1/2)) in primary cultures of mouse astrocytes and showed that it is evoked by alpha(2)-adrenoceptor-mediated transactivation of epidermal growth factor (EGF) receptors, a known response to activation of G(i/o)- or G(q)-coupled receptors [Li, B., Du, T., Li, H., Gu, L., Zhang, H., Huang, J., Hertz, L., Peng, L., 2008a. Signaling pathways for transactivation by dexmedetomidine of epidermal growth factor receptors in astrocytes and its paracrine effect on neurons. Br. J. Pharmacol. 154, 191-203]. Like most studies of transactivation, that study used cultured cells, raising the question whether a similar effect can be demonstrated in intact brain tissue and the brain in vivo. In the present study we have shown that (i) dexmedetomidine-mediated ERK(1/2) phosphorylation occurs in mouse brain slices with a similar concentration dependence as in cultured astrocytes (near-maximum effect at 50nM); (ii) intraperitoneal injection of dexmedetomidine (3microg/kg) in adult mice causes rapid phosphorylation of the EGF receptor (at Y845 and Y992) and of ERK(1/2) in the brain; (iii) both EGF receptor and ERK(1/2) phosphorylation are inhibited by intraventricular administration of (a) AG 1478, a specific inhibitor of the receptor-tyrosine kinase of the EGF receptor; (b) GM 6001, an inhibitor of metalloproteinase(s) required for release of EGF receptor agonists from membrane-bound precursors; or (c) heparin, neutralizing heparin-binding EGF (HB-EGF). Thus, in intact brain HB-EGF, known to be expressed in brain, may be the major EGF agonist released in response to stimulation of alpha(2)-adrenoceptors, the released agonist(s) activate(s) EGF receptors, and ERK(1/2) is phosphorylated as a conventional response to EGF receptor activation. Our previous paper (see above) showed that dexmedetomidine evokes no ERK(1/2) phosphorylation in cultured neurons, but neurons

  7. Ankyrin-binding activity of nervous system cell adhesion molecules expressed in adult brain.

    PubMed

    Davis, J Q; Bennett, V

    1993-01-01

    A family of ankyrin-binding glycoproteins have been identified in adult rat brain that include alternatively spliced products of the same pre-mRNA. A composite sequence of ankyrin-binding glycoprotein (ABGP) shares 72% amino acid sequence identity with chicken neurofascin, a membrane-spanning neural cell adhesion molecule in the Ig super-family expressed in embryonic brain. ABGP polypeptides and ankyrin associate as pure proteins in a 1:1 molar stoichiometry at a site located in the predicted cytoplasmic domain. ABGP polypeptides are expressed late in postnatal development to approximately the same levels as ankyrin, and comprise a significant fraction of brain membrane proteins. Immunofluorescence studies have shown that ABGP polypeptides are co-localized with ankyrinB. Major differences in developmental expression have been reported for neurofascin in embryos compared with the late postnatal expression of ABGP, suggesting that ABGP and neurofascin represent products of gene duplication events that have subsequently evolved in parallel with distinct roles. Predicted cytoplasmic domains of rat ABGP and chicken neurofascin are nearly identical to each other and closely related to a group of nervous system cell adhesion molecules with variable extracellular domains, including L1, Nr-CAM and Ng-CAM of vertebrates, and neuroglian of Drosophila. A hypothesis to be evaluated is that ankyrin-binding activity is shared by all of these proteins.

  8. Pre-Adult MRI of Brain Cancer and Neurological Injury: Multivariate Analyses

    PubMed Central

    Levman, Jacob; Takahashi, Emi

    2016-01-01

    Brain cancer and neurological injuries, such as stroke, are life-threatening conditions for which further research is needed to overcome the many challenges associated with providing optimal patient care. Multivariate analysis (MVA) is a class of pattern recognition technique involving the processing of data that contains multiple measurements per sample. MVA can be used to address a wide variety of neuroimaging challenges, including identifying variables associated with patient outcomes; understanding an injury’s etiology, development, and progression; creating diagnostic tests; assisting in treatment monitoring; and more. Compared to adults, imaging of the developing brain has attracted less attention from MVA researchers, however, remarkable MVA growth has occurred in recent years. This paper presents the results of a systematic review of the literature focusing on MVA technologies applied to brain injury and cancer in neurological fetal, neonatal, and pediatric magnetic resonance imaging (MRI). With a wide variety of MRI modalities providing physiologically meaningful biomarkers and new biomarker measurements constantly under development, MVA techniques hold enormous potential toward combining available measurements toward improving basic research and the creation of technologies that contribute to improving patient care. PMID:27446888

  9. Neurobiological markers of exercise-related brain plasticity in older adults

    PubMed Central

    Voss, Michelle W.; Erickson, Kirk I.; Prakash, Ruchika Shaurya; Chaddock, Laura; Kim, Jennifer S.; Alves, Heloisa; Szabo, Amanda; White, Siobhan M.; Wójcicki, Thomas R.; Mailey, Emily L.; Olson, Erin A.; Gothe, Neha; Potter, Vicki V.; Martin, Stephen A.; Pence, Brandt D.; Cook, Marc D.; Woods, Jeffrey A.; McAuley, Edward; Kramer, Arthur F.

    2012-01-01

    The current study examined how a randomized one-year aerobic exercise program for healthy older adults would affect serum levels of brain-derived neurotrophic factor (BDNF), insulin-like growth factor type 1 (IGF-1), and vascular endothelial growth factor (VEGF) - putative markers of exercise-induced benefits on brain function. The study also examined whether (a) change in the concentration of these growth factors was associated with alterations in functional connectivity following exercise, and (b) the extent to which pre-intervention growth factor levels were associated with training-related changes in functional connectivity. In 65 participants (mean age = 66.4), we found that although there were no group-level changes in growth factors as a function of the intervention, increased temporal lobe connectivity between the bilateral parahippocampus and the bilateral middle temporal gyrus was associated with increased BDNF, IGF-1, and VEGF for an aerobic walking group but not for a non-aerobic control group, and greater pre-intervention VEGF was associated with greater training-related increases in this functional connection. Results are consistent with animal models of exercise and the brain, but are the first to show in humans that exercise-induced increases in temporal lobe functional connectivity are associated with changes in growth factors and may be augmented by greater baseline VEGF. PMID:23123199

  10. Pre-Adult MRI of Brain Cancer and Neurological Injury: Multivariate Analyses.

    PubMed

    Levman, Jacob; Takahashi, Emi

    2016-01-01

    Brain cancer and neurological injuries, such as stroke, are life-threatening conditions for which further research is needed to overcome the many challenges associated with providing optimal patient care. Multivariate analysis (MVA) is a class of pattern recognition technique involving the processing of data that contains multiple measurements per sample. MVA can be used to address a wide variety of neuroimaging challenges, including identifying variables associated with patient outcomes; understanding an injury's etiology, development, and progression; creating diagnostic tests; assisting in treatment monitoring; and more. Compared to adults, imaging of the developing brain has attracted less attention from MVA researchers, however, remarkable MVA growth has occurred in recent years. This paper presents the results of a systematic review of the literature focusing on MVA technologies applied to brain injury and cancer in neurological fetal, neonatal, and pediatric magnetic resonance imaging (MRI). With a wide variety of MRI modalities providing physiologically meaningful biomarkers and new biomarker measurements constantly under development, MVA techniques hold enormous potential toward combining available measurements toward improving basic research and the creation of technologies that contribute to improving patient care. PMID:27446888

  11. Neurobiological markers of exercise-related brain plasticity in older adults.

    PubMed

    Voss, Michelle W; Erickson, Kirk I; Prakash, Ruchika Shaurya; Chaddock, Laura; Kim, Jennifer S; Alves, Heloisa; Szabo, Amanda; Phillips, Siobhan M; Wójcicki, Thomas R; Mailey, Emily L; Olson, Erin A; Gothe, Neha; Vieira-Potter, Victoria J; Martin, Stephen A; Pence, Brandt D; Cook, Marc D; Woods, Jeffrey A; McAuley, Edward; Kramer, Arthur F

    2013-02-01

    The current study examined how a randomized one-year aerobic exercise program for healthy older adults would affect serum levels of brain-derived neurotrophic factor (BDNF), insulin-like growth factor type 1 (IGF-1), and vascular endothelial growth factor (VEGF) - putative markers of exercise-induced benefits on brain function. The study also examined whether (a) change in the concentration of these growth factors was associated with alterations in functional connectivity following exercise, and (b) the extent to which pre-intervention growth factor levels were associated with training-related changes in functional connectivity. In 65 participants (mean age=66.4), we found that although there were no group-level changes in growth factors as a function of the intervention, increased temporal lobe connectivity between the bilateral parahippocampus and the bilateral middle temporal gyrus was associated with increased BDNF, IGF-1, and VEGF for an aerobic walking group but not for a non-aerobic control group, and greater pre-intervention VEGF was associated with greater training-related increases in this functional connection. Results are consistent with animal models of exercise and the brain, but are the first to show in humans that exercise-induced increases in temporal lobe functional connectivity are associated with changes in growth factors and may be augmented by greater baseline VEGF.

  12. Sex hormones affect neurotransmitters and shape the adult female brain during hormonal transition periods

    PubMed Central

    Barth, Claudia; Villringer, Arno; Sacher, Julia

    2015-01-01

    Sex hormones have been implicated in neurite outgrowth, synaptogenesis, dendritic branching, myelination and other important mechanisms of neural plasticity. Here we review the evidence from animal experiments and human studies reporting interactions between sex hormones and the dominant neurotransmitters, such as serotonin, dopamine, GABA and glutamate. We provide an overview of accumulating data during physiological and pathological conditions and discuss currently conceptualized theories on how sex hormones potentially trigger neuroplasticity changes through these four neurochemical systems. Many brain regions have been demonstrated to express high densities for estrogen- and progesterone receptors, such as the amygdala, the hypothalamus, and the hippocampus. As the hippocampus is of particular relevance in the context of mediating structural plasticity in the adult brain, we put particular emphasis on what evidence could be gathered thus far that links differences in behavior, neurochemical patterns and hippocampal structure to a changing hormonal environment. Finally, we discuss how physiologically occurring hormonal transition periods in humans can be used to model how changes in sex hormones influence functional connectivity, neurotransmission and brain structure in vivo. PMID:25750611

  13. Effects of neonatal treatment with the TRPV1 agonist, capsaicin, on adult rat brain and behaviour.

    PubMed

    Newson, Penny N; van den Buuse, Maarten; Martin, Sally; Lynch-Frame, Ann; Chahl, Loris A

    2014-10-01

    Treatment of neonatal rats with the transient receptor potential vanilloid 1 (TRPV1) channel agonist, capsaicin, produces life-long loss of sensory neurons expressing TRPV1 channels. Previously it was shown that rats treated on day 2 of life with capsaicin had behavioural hyperactivity in a novel environment at 5-7 weeks of age and brain changes reminiscent of those found in subjects with schizophrenia. The objective of the present study was to investigate brain and behavioural responses of adult rats treated as neonates with capsaicin. It was found that the brain changes found at 5-7 weeks in rats treated as neonates with capsaicin persisted into adulthood (12 weeks) but were less in older rats (16-18 weeks). Increased prepulse inhibition (PPI) of acoustic startle was found in these rats at 8 and 12 weeks of age rather than the deficit commonly found in animal models of schizophrenia. Subjects with schizophrenia also have reduced flare responses to niacin and methylnicotinate proposed to be mediated by prostaglandin D2 (PGD2). Flare responses are accompanied by cutaneous plasma extravasation. It was found that the cutaneous plasma extravasation responses to methylnicotinate and PGD2 were reduced in capsaicin-treated rats. In conclusion, several neuroanatomical changes observed in capsaicin-treated rats, as well as the reduced cutaneous plasma extravasation responses, indicate that the role of TRPV1 channels in schizophrenia is worthy of investigation.

  14. Neurobehavioural treatment for obsessive-compulsive disorder in an adult with traumatic brain injury.

    PubMed

    Arco, Lucius

    2008-01-01

    Although obsessive-compulsive disorder has been reported as one of many anxiety-related sequelae of brain injury, few empirical data of its responsiveness to psychological intervention are available. In this study, a single participant changing criterion experimental design was used to evaluate a neurobehavioural intervention for compulsive behaviour of an adult with severe traumatic brain injury. The participant, a man aged 24 years, had sustained frontal-temporal lobe brain trauma 12 months earlier, and presented with compulsive counting and voiding of bladder. The neurobehavioural intervention consisted of regular in-home consultations, self-regulation procedures including self-recording of compulsive behaviour, stress-coping strategies, errorless remediation, social reinforcement, and gradual fading of intervention. Baseline showed counting occurred on average 80% of daily hourly intervals, and voiding 12 times per day. Intervention produced elimination of compulsive counting, acceptable voiding at 8 times per day, and reports of the participant's satisfaction with intervention methods and outcomes. At 6 months follow-up, counting remained at zero levels, and voiding had decreased further to 7 times per day.

  15. Brain apoptosis signaling pathways are regulated by methylphenidate treatment in young and adult rats.

    PubMed

    Réus, Gislaine Z; Scaini, Giselli; Jeremias, Gabriela C; Furlanetto, Camila B; Morais, Meline O S; Mello-Santos, Lis Maira; Quevedo, João; Streck, Emilio L

    2014-10-01

    Methylphenidate (MPH) is commonly prescribed for children who have been diagnosed with attention deficit hyperactivity disorder (ADHD); however, the action mechanisms of methylphenidate have not been fully elucidated. Studies have shown a relationship between apoptosis signaling pathways and psychiatric disorders, as well as in therapeutic targets for such disorders. So, we investigated if chronic treatment with MPH at doses of 1, 2 and 10mg/kg could alter the levels of pro-apoptotic protein, Bax, anti-apoptotic protein, Bcl-2, caspase-3 and cytochrome c in the brain of young and adult Wistar rats. Our results showed that MPH at all doses increased Bax in the cortex; the Bcl-2 and caspase-3 were increased with MPH (1mg/kg) and were reduced with MPH (2 and 10mg/kg); the cytochrome c was reduced in the cortex after treatment with MPH at all doses; in the cerebellum there was an increase of Bax with MPH at all doses, however, there was a reduction of Bcl-2, caspase-3, and cytochrome c with MPH (2 and 10mg/kg); in the striatum the treatment with MPH (10mg/kg) decreased caspase-3 and cytochrome c; treatment with MPH (2 and 10mg/kg) increased Bax and decreased Bcl-2 in the hippocampus; and the caspase-3 and cytochrome c were reduced in the hippocampus with MPH (10mg/kg). In conclusion, our results suggest that MPH influences plasticity in the brain of young and adult rats; however, the effects were dependent of age and brain area, on the one hand activating the initial cascade of apoptosis, increasing Bax and reducing Bcl-2, but otherwise inhibiting apoptosis by reduction of caspase-3 and cytochrome c. PMID:25128604

  16. Prenatal cocaine exposure alters progenitor cell markers in the subventricular zone of the adult rat brain

    PubMed Central

    Patel, Dhyanesh Arvind; Booze, Rosemarie M.; Mactutus, Charles F.

    2013-01-01

    Long-term consequences of early developmental exposure to drugs of abuse may have deleterious effects on the proliferative plasticity of the brain. The purpose of this study was to examine the long-term effects of prenatal exposure to cocaine, using the IV route of administration and doses that mimic the peak arterial levels of cocaine use in humans, on the proliferative cell types of the subventricular zones (SVZ) in the adult (180 days-old) rat brain. Employing immunocytochemistry, the expression of GFAP+ (type B cells) and nestin+(GFAP−) (Type C and A cells) staining was quantified in the subcallosal area of the SVZ. GFAP+ expression was significantly different between the prenatal cocaine treated group and the vehicle (saline) control group. The prenatal cocaine treated group possessed significantly lower GFAP+ expression relative to the vehicle control group, suggesting that prenatal cocaine exposure significantly reduced the expression of type B neural stem cells of the SVZ. In addition, there was a significant sex difference in nestin+ expression with females showing approximately 8–13% higher nestin+ expression compared to the males. More importantly, a significant prenatal treatment condition (prenatal cocaine, control) by sex interaction in nestin+ expression was confirmed, indicating different effects of cocaine based on sex of the animal. Specifically, prenatal cocaine exposure eliminated the basal difference between the sexes. Collectively, the present findings suggest that prenatal exposure to cocaine, when delivered via a protocol designed to capture prominent features of recreational usage, can selectively alter the major proliferative cell types in the subcallosal area of the SVZ in an adult rat brain, and does so differently for males and females. PMID:22119286

  17. Magnetic resonance imaging of the brain in adults with severe falciparum malaria

    PubMed Central

    2014-01-01

    Background Magnetic resonance imaging (MRI) allows detailed study of structural and functional changes in the brain in patients with cerebral malaria. Methods In a prospective observational study in adult Bangladeshi patients with severe falciparum malaria, MRI findings in the brain were correlated with clinical and laboratory parameters, retinal photography and optic nerve sheath diameter (ONSD) ultrasound (a marker of intracranial pressure). Results Of 43 enrolled patients, 31 (72%) had coma and 12 (28%) died. MRI abnormalities were present in 79% overall with mostly mild changes in a wide range of anatomical sites. There were no differences in MRI findings between patients with cerebral and non-cerebral or fatal and non-fatal disease. Subtle diffuse cerebral swelling was common (n = 22