Brain Volume Fractions in Mammals in Relation to Behavior in Carnivores, Primates, Ungulates, and Rodents

The volume fraction (VF) of a given brain region, or the proper mass, ought to reflect the importance of that region in the life of a given species. This study sought to examine the VF of various brain regions across 61 different species of mammals to discern if there were regularities or differences among mammalian orders. We examined the brains of carnivores (n = 17), ungulates (n = 8), rodents (n = 7), primates (n = 11), and other mammals (n = 18) from the online collections at the National Museum of Health and Medicine. We measured and obtained the VF of several brain regions: the striatum, thalamus, neocortex, cerebellum, hippocampus, and piriform area. We refined our analyses by using phylogenetic size correction, yielding the corrected (c)VF. Our groups showed marked differences in gross brain architecture. Primates and carnivores were divergent in some measures, particularly the cVF of the striatum, even though their overall brain size range was roughly the same. Rodents predictably had relatively large cVFs of subcortical structures due to the fact that their neocortical cVF was smaller, particularly when compared to primates. Not so predictably, rodents had the largest cerebellar cVF, and there were marked discrepancies in cerebellar data across groups. Ungulates had a larger piriform area than primates, perhaps due to their olfactory processing abilities. We provide interpretations of our results in the light of the comparative behavioral and neuroanatomical literature.

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Reduced Brain Volume and White Matter Alterations in Shank3-Deficient Rats

10.21203/rs.3.rs-100329/v1 ◽

2020 ◽

Author(s):

Carla Esther Meyer Golden ◽

Victoria X Wang ◽

Hala Harony-Nicolas ◽

Patrick R. Hof ◽

Joseph Buxbaum

Keyword(s):

White Matter ◽

Brain Structure ◽

Brain Volume ◽

Diffusion Tensor ◽

Brain Size ◽

Brain Regions ◽

Autism Spectrum ◽

Wild Type ◽

Microstructural Alterations ◽

The Brain

Abstract Background: Mutations and deletions in the SHANK3 synaptic gene cause the major neurodevelopmental features of Phelan-McDermid syndrome (PMS). The SHANK3 gene encodes a key structural component of excitatory synapses that is important for synaptogenesis. PMS is characterized by intellectual disability, autism spectrum disorder, cognitive deficits, physical dysmorphic features, sensory hyporeactivity, and alterations in the size of multiple brain regions. Clinical assessments and limited imaging studies have revealed a reduction in volume of multiple brain regions. They have also found white matter thinning and microstructural alterations to be persistent in patients with PMS. While many of these impairments have been replicated in mouse models of PMS, the brain structure of a rat model has not yet been studied. Methods: We assessed the brain structure of haploinsufficient and homozygous Shank3-deficient rats that model the behavioral deficits of PMS with magnetic resonance and diffusion tensor imaging, and compared their brain structure to wild type littermates.Results: Both gray and white matter structures were smaller in Shank3-deficient rats, leading to an overall reduction in brain size compared to wild type littermates. The largest region to be diminished in size was the neocortex. Some regions involved in sensory processing and white matter regions were also reduced in size. Lastly, the microstructure of two white matter tracts, the external capsule and fornix, was abnormal.Conclusions: Shank3-deficient rats replicate the reduced brain volume and altered white matter phenotypes present in individuals with PMS. Therefore, the brain regions that were altered represent potential cross-species structural biomarkers that warrant further study.

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The relationships between brain regions and forelimb dexterity in marsupials (Marsupialia): a comparative test of the principle of proper mass

Australian Journal of Zoology ◽

10.1071/zo99043 ◽

2000 ◽

Vol 48 (1) ◽

pp. 99 ◽

Cited By ~ 11

Author(s):

Andrew N. Iwaniuk ◽

John E. Nelson ◽

Ian Q. Whishaw

Keyword(s):

Brain Cortex ◽

Brain Size ◽

Brain Regions ◽

Brain Morphology ◽

Proper Mass ◽

Contrast Analysis ◽

Independent Contrast ◽

The Relationship ◽

The Brain ◽

Forelimb Movements

A behavioural index of forelimb dexterity and comparative statistics were used to analyse the relationships between proximal (shoulder, upper and lower forelimb) and distal (wrist, forepaw, digits) forelimb dexterity and four aspects of brain morphology (overall brain, cortex, cerebellum and telencephalon sizes) in 18 species of marsupials. On the basis of the principle of proper mass, it was expected that an increase in forelimb dexterity (either proximal or distal) would be positively correlated with the size of the brain and the three brain components. Using independent contrast analysis to remove the effects of phylogeny revealed three significant correlations between: cortex size and distal dexterity, cerebellum size and proximal dexterity, and telencephalon size and distal dexterity. The relationship between cortex size and distal dexterity was subsequently corroborated by Spearman rank correlations. These results suggest that the execution of finely coordinated forelimb movements may not be dependent upon overall brain size, but may be dependent upon the size of brain components, thus supporting the principle of proper mass.

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Sexually dimorphic neuroanatomical differences relate to ASD-relevant behavioral outcomes in a maternal autoantibody mouse model

Molecular Psychiatry ◽

10.1038/s41380-021-01215-w ◽

2021 ◽

Author(s):

Matthew R. Bruce ◽

Karen L. Jones ◽

Anthony C. Vernon ◽

Jill L. Silverman ◽

Jacqueline N. Crawley ◽

...

Keyword(s):

Mouse Model ◽

Brain Volume ◽

Brain Size ◽

Ex Vivo ◽

Fetal Brain ◽

Brain Regions ◽

Prenatally Exposed ◽

Total Brain Volume ◽

Male And Female ◽

Peptide Epitopes

AbstractImmunoglobulin G (IgG) autoantibodies reactive to fetal brain proteins in mothers of children with ASD have been described by several groups. To understand their pathologic significance, we developed a mouse model of maternal autoantibody related ASD (MAR-ASD) utilizing the peptide epitopes from human autoantibody reactivity patterns. Male and female offspring prenatally exposed to the salient maternal autoantibodies displayed robust deficits in social interactions and increased repetitive self-grooming behaviors as juveniles and adults. In the present study, neuroanatomical differences in adult MAR-ASD and control offspring were assessed via high-resolution ex vivo magnetic resonance imaging (MRI) at 6 months of age. Of interest, MAR-ASD mice displayed significantly larger total brain volume and of the 159 regions examined, 31 were found to differ significantly in absolute volume (mm3) at an FDR of <5%. Specifically, the absolute volumes of several white matter tracts, cortical regions, and basal nuclei structures were significantly increased in MAR-ASD animals. These phenomena were largely driven by female MAR-ASD offspring, as no significant differences were seen with either absolute or relative regional volume in male MAR-ASD mice. However, structural covariance analysis suggests network-level desynchronization in brain volume in both male and female MAR-ASD mice. Additionally, preliminary correlational analysis with behavioral data relates that volumetric increases in numerous brain regions of MAR-ASD mice were correlated with social interaction and repetitive self-grooming behaviors in a sex-specific manner. These results demonstrate significant sex-specific effects in brain size, regional relationships, and behavior for offspring prenatally exposed to MAR-ASD autoantibodies relative to controls.

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

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1980.238.1.r76 ◽

1980 ◽

Vol 238 (1) ◽

pp. R76-R81 ◽

Cited By ~ 2

Author(s):

H. F. Cserr ◽

M. Bundgaard ◽

J. K. Ashby ◽

M. Murray

Keyword(s):

Choroid Plexus ◽

Brain Volume ◽

Brain Size ◽

Ventricular Volume ◽

Brain Weight ◽

Air Breathing ◽

Original Proposal ◽

Adaptive Value ◽

Choroid Plexuses ◽

The Brain

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

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A three-dimensional thalamocortical dataset for characterizing brain heterogeneity

10.1101/2020.05.22.111617 ◽

2020 ◽

Cited By ~ 2

Author(s):

Judy A. Prasad ◽

Aishwarya H. Balwani ◽

Erik C. Johnson ◽

Joseph D. Miano ◽

Vandana Sampathkumar ◽

...

Keyword(s):

Three Dimensional ◽

Brain Regions ◽

Regions Of Interest ◽

Subcortical Structures ◽

Neural Structure ◽

Brain Areas ◽

X Ray ◽

Anatomical Imaging ◽

Brain Pathways ◽

Critical Aspects

AbstractNeural cytoarchitecture is heterogeneous, varying both across and within brain regions. The consistent identification of regions of interest is one of the most critical aspects in examining neurocircuitry, as these structures serve as the vital landmarks with which to map brain pathways. Access to continuous, three-dimensional volumes that span multiple brain areas not only provides richer context for identifying such landmarks, but also enables a deeper probing of the microstructures within. Here, we describe a three-dimensional X-ray microtomography imaging dataset of a well-known and validated thalamocortical sample, encompassing a range of cortical and subcortical structures. In doing so, we provide the field with access to a micron-scale anatomical imaging dataset ideal for studying heterogeneity of neural structure.

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A sub+ cortical fMRI-based surface parcellation

10.1101/2019.12.20.883553 ◽

2019 ◽

Author(s):

John D. Lewis ◽

Gleb Bezgin ◽

Vladimir S. Fonov ◽

D. Louis Collins ◽

Alan C. Evans

Keyword(s):

Individual Differences ◽

Functional Connectivity ◽

Life Span ◽

Brain Volume ◽

Subcortical Structures ◽

Common Space ◽

Cortical Parcellation ◽

Connectivity Patterns ◽

Deep Gray Matter ◽

Volumetric Registration

AbstractBoth the cortex and the subcortical structures are organized into a large number of distinct areas reflecting functional and cytoarchitectonic differences. Mapping these areas is of fundamental importance to neuroscience. A central obstacle to this task is the inaccuracy associated with mapping results from individuals into a common space. The vast individual differences in morphology pose a serious problem for volumetric registration. Surface-based approaches fare substantially better, but have thus far been used only for cortical parcellation. We extend this surface-based approach to include also the subcortical deep gray-matter structures. Using the life-span data from the Enhanced Nathan Klein Institute - Rockland Sample, comprised of data from 590 individuals from 6 to 85 years of age, we generate a functional parcellation of both the cortical and subcortical surfaces. To assess this extended parcellation, we show that our extended functional parcellation provides greater homogeneity of functional connectivity patterns than do arbitrary parcellations matching in the number and size of parcels. We also show that our subcortical parcels align with known subnuclei. Further, we show that this parcellation is appropriate for use with data from other modalities; we generate cortical and subcortical white/gray contrast measures for this same dataset, and draw on the fact that areal differences are evident in the relation of white/gray contrast to age, to sex, to brain volume, and to interactions of these terms; we show that our extended functional parcellation provides an improved fit to the complexity of the life-span changes in the white/gray contrast data compared to arbitrary parcellations matching in the number and size of parcels. We provide our extended functional parcellation for the use of the neuroimaging community.

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Emotional aspects of language

ANALES RANM ◽

10.32440/ar.2018.135.02.supl01.art04 ◽

2018 ◽

Vol 135 (135(02)) ◽

pp. 41-46

Author(s):

J.A. Hinojosa ◽

E.M. Moreno ◽

P. Ferré ◽

M.A. Pozo

Keyword(s):

Language Processing ◽

Language Comprehension ◽

Developmental Psychology ◽

Brain Regions ◽

Emotional Content ◽

Current Work ◽

Subcortical Structures ◽

Emotional Aspects ◽

The Relationship ◽

And Linguistics

Up to date the study of the relationship between language and emotion has received little attention from researchers. In the current work we will summarize evidence coming from the fields of developmental psychology and affective neurolinguistics. The results from different studies indicate that learning emotional language has its own idiosyncrasy. Also, the emotional content of words, sentences and texts modulates several levels of language processing, including phonological, lexico-semantic and morpho-syntactic aspects of language comprehension and production. Finally, the interactions between language and emotion involve the activation of several brain regions linked to distinct affective and linguistics processes, like parts of frontal and temporal cortices or subcortical structures such as the amygdala. Overall, the results of these studies clearly show that emotional content determines certain aspects of how we acquire and process language.

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Convergent mosaic brain evolution is associated with the evolution of novel electrosensory systems in teleost fishes

10.1101/2021.09.29.462233 ◽

2021 ◽

Author(s):

Erika L. Schumacher ◽

Bruce A. Carlson

Keyword(s):

Brain Region ◽

Brain Size ◽

Brain Evolution ◽

Brain Regions ◽

Torus Semicircularis ◽

Micro Computed Tomography ◽

Electrosensory System ◽

Electric Fishes ◽

Weakly Electric ◽

Region Size

AbstractBrain region size generally scales allometrically with total brain size, but mosaic shifts in brain region size independent of brain size have been found in several lineages and may be related to the evolution of behavioral novelty. African weakly electric fishes (Mormyroidea) evolved a mosaically enlarged cerebellum and hindbrain, yet the relationship to their behaviorally novel electrosensory system remains unclear. We addressed this by studying South American weakly electric fishes (Gymnotiformes) and weakly electric catfishes (Synodontis spp.), which evolved varying aspects of electrosensory systems, independent of mormyroids. If the mormyroid mosaic increases are related to evolving an electrosensory system, we should find similar mosaic shifts in gymnotiforms and Synodontis. Using micro-computed tomography scans, we quantified brain region scaling for multiple electrogenic, electroreceptive, and non-electrosensing species. We found mosaic increases in cerebellum in all three electrogenic lineages relative to non-electric lineages and mosaic increases in torus semicircularis and hindbrain associated with the evolution of electrogenesis and electroreceptor type. These results show that evolving novel electrosensory systems is repeatedly and independently associated with changes in the sizes of individual brain regions independent of brain size, which suggests that selection can impact structural brain composition to favor specific regions involved in novel behaviors.

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

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2015.1008 ◽

2015 ◽

Vol 282 (1810) ◽

pp. 20151008 ◽

Cited By ~ 25

Author(s):

Kristina Noreikiene ◽

Gábor Herczeg ◽

Abigél Gonda ◽

Gergely Balázs ◽

Arild Husby ◽

...

Keyword(s):

Body Size ◽

Brain Size ◽

Additive Genetic Variance ◽

Genetic Correlations ◽

Relative Size ◽

Strong Support ◽

Brain Evolution ◽

Brain Regions ◽

Independent Evolution ◽

Mosaic Model

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 h 2 = 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 r G = 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 ( r G = 0.89), suggesting a constraint for independent evolution of brain and body size in sticklebacks.

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Brain regions associated with visual cues are important for bird migration

Biology Letters ◽

10.1098/rsbl.2015.0678 ◽

2015 ◽

Vol 11 (11) ◽

pp. 20150678 ◽

Cited By ~ 11

Author(s):

Orsolya Vincze ◽

Csongor I. Vágási ◽

Péter L. Pap ◽

Gergely Osváth ◽

Anders Pape Møller

Keyword(s):

Visual Cues ◽

Optic Lobe ◽

Brain Size ◽

Relative Size ◽

Bird Species ◽

Interspecific Variation ◽

Brain Regions ◽

Long Distance ◽

Migration Distance ◽

Whole Brain

Long-distance migratory birds have relatively smaller brains than short-distance migrants or residents. Here, we test whether reduction in brain size with migration distance can be generalized across the different brain regions suggested to play key roles in orientation during migration. Based on 152 bird species, belonging to 61 avian families from six continents, we show that the sizes of both the telencephalon and the whole brain decrease, and the relative size of the optic lobe increases, while cerebellum size does not change with increasing migration distance. Body mass, whole brain size, optic lobe size and wing aspect ratio together account for a remarkable 46% of interspecific variation in average migration distance across bird species. These results indicate that visual acuity might be a primary neural adaptation to the ecological challenge of migration.

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