Complex behavioral plasticity is not reduced in spiderlings with miniature brains

The brains of smaller animals are smaller than those of their larger relatives, but it is not clear whether their adaptive behavioral flexibility is more limited. Previous interspecific comparisons found that aspects of web construction behavior of very small orb weaving spiders (0.005 mg) were no less precise than those of much larger related orb weavers (30 mg), but the behaviors tested were relatively simple. Here we perform a more sensitive intraspecific test involving the multiple behavioral adjustments of orb web designs made by Leucauge argyra to confinement in very small spaces. Web adjustments of spiderlings as small as ~0.1 mg were compared to previously published observations of ~80 mg conspecific adults. Spiderlings in constrained spaces made all of the complex adjustments made by adults in at least seven independent web design variables, and their adjustments were no less precise. Rough estimates based on previously published data on total brain volumes and the mean diameters of neuron cell bodies suggested that spiderlings and adult females of Leucauge may have similar numbers of neurons, due to spiderlings having smaller neurons and a greater percentage of body tissues dedicated to the brain. We speculate that this neural similarity may explain why L. argyra spiderlings showed no behavioral deficits compared with adults.

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Phenotypic plasticity

10.1093/oso/9780198797500.003.0005 ◽

2018 ◽

Author(s):

Karen D. Williams ◽

Marla B. Sokolowski

Keyword(s):

Gene Expression ◽

Phenotypic Plasticity ◽

Environmental Change ◽

Behavioral Plasticity ◽

Behavioral Flexibility ◽

Insect Behavior ◽

Behavioral Variability ◽

Gene By Environment Interactions ◽

Affect Gene Expression

Why is there so much variation in insect behavior? This chapter will address the sources of behavioral variability, with a particular focus on phenotypic plasticity. Variation in social, nutritional, and seasonal environmental contexts during development and adulthood can give rise to phenotypic plasticity. To delve into mechanism underlying behavioral flexibility in insects, examples of polyphenisms, a type of phenotypic plasticity, will be discussed. Selected examples reveal that environmental change can affect gene expression, which in turn can affect behavioral plasticity. These changes in gene expression together with gene-by-environment interactions are discussed to illuminate our understanding of insect behavioral plasticity.

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Postnatal Decrease in Circulating Insulin-Like Growth Factor-I and Low Brain Volumes in Very Preterm Infants

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2010-2440 ◽

2011 ◽

Vol 96 (4) ◽

pp. 1129-1135 ◽

Cited By ~ 39

Author(s):

Ingrid Hansen-Pupp ◽

Holger Hövel ◽

Ann Hellström ◽

Lena Hellström-Westas ◽

Chatarina Löfqvist ◽

...

Keyword(s):

White Matter ◽

Magnetic Resonance ◽

Preterm Infants ◽

Brain Volumes ◽

Very Preterm Infants ◽

Very Preterm ◽

Matter Volume ◽

Total Brain ◽

Igf I ◽

Igfbp 3

Abstract Context: IGF-I and IGF binding protein-3 (IGFBP-3) are essential for growth and maturation of the developing brain. Objective: The aim of this study was to evaluate the association between postnatal serum concentrations of IGF-I and IGFBP-3 and brain volumes at term in very preterm infants. Design: Fifty-one infants with a mean (sd) gestational age (GA) of 26.4 (1.9) wk and birth weight (BW) of 888 (288) g were studied, with weekly blood sampling of IGF-I and IGFBP-3 from birth until 35 gestational weeks (GW) and daily calculation of protein and caloric intake. Magnetic resonance images obtained at 40 GW were segmented into total brain, cerebellar, cerebrospinal fluid, gray matter, and unmyelinated white matter volumes. Main Outcome Measures: We evaluated brain growth by measuring brain volumes using magnetic resonance imaging. Results: Mean IGF-I concentrations from birth to 35 GW correlated with total brain volume, unmyelinated white matter volume, gray matter volume, and cerebellar volume [r = 0.55 (P < 0.001); r = 0.55 (P < 0.001); r = 0.44 (P = 0.002); and r = 0.58 (P < 0.001), respectively]. Similar correlations were observed for IGFBP-3 concentrations. Correlations remained after adjustment for GA, mean protein and caloric intakes, gender, severe brain damage, and steroid treatment. Protein and caloric intakes were not related to brain volumes. Infants with BW small for GA had lower mean concentrations of IGF-I (P = 0.006) and smaller brain volumes (P = 0.001–0.013) than infants with BW appropriate for GA. Conclusion: Postnatal IGF-I and IGFBP-3 concentrations are positively associated with brain volumes at 40 GW in very preterm infants. Normalization of the IGF-I axis, directly or indirectly, may support normal brain development in very preterm infants.

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Abstract P420: Alcohol Consumption and Longitudinal Changes in Magnetic Resonance Imaging-defined Brain Abnormalities: The Cardiovascular Health Study

Circulation ◽

10.1161/circ.141.suppl_1.p420 ◽

2020 ◽

Vol 141 (Suppl_1) ◽

Author(s):

Simona Costanzo ◽

Traci M Bartz ◽

Giovanni de Gaetano ◽

Augusto F Di Castelnuovo ◽

Licia Iacoviello ◽

...

Keyword(s):

White Matter ◽

Alcohol Consumption ◽

Brain Atrophy ◽

Alcohol Intake ◽

Cardiovascular Health ◽

Health Study ◽

Cardiovascular Health Study ◽

Brain Volumes ◽

Total Brain

Introduction: Alcohol intake has been related with a complex group of associations with brain structure in cross-sectional analyses, but to our knowledge, its prospective relationship with structural brain abnormalities detected by MRI has never been reported. Hypothesis: We hypothesized that consumers of 1-<7 drinks/week would have slower progression of leukoaraiosis (white matter abnormalities) but more rapid progression of brain atrophy than longer-term abstainers. Methods: As part of the Cardiovascular Health Study, 1 996 adults aged ≥65 years underwent MRI scanning in 1991-94 and again in 1997-99, having excluded 120 participants with a history of cerebrovascular disease before the initial scan. Alcohol consumption was assessed at each annual visit by self-reported intake of wine, beer and liquor. A 10-point white matter grade (WMG) and ventricular grade (VG) were assessed in a standardized and blinded manner in both scans; hippocampal and total brain volumes were also quantified on the second scan. We estimated the associations of alcohol intake in categories (as reported closest to the date of initial scan), with MRI findings at follow-up with multinomial ordered logistic regression (WMG ≤ 3 ref and ≥ 4; VG ≤ 3 ref , =4 and ≥5) using inverse probability weighting to account for attrition. Results: We observed a U-shaped association with WMG, with significantly lower risk among participants consuming 1-<7 drinks/week (OR 0.38; 95% CI 0.17-0.82, table) than long-term abstainers (P quadtrend = 0.01). For VG, the association was inverse (P trend = 0.06), with significantly less progression among drinkers of 1-<7 drinks/week than long-term abstainers (OR 0.62; 95% CI 0.40-0.97). We identified no significant associations of alcohol intake with quantitative mean hippocampal or total brain volumes at the second scan. Conclusions: Compared with long-term abstention, consumption of 1-<7 drinks/week of alcohol was generally associated with less progression of leukoaraiosis and some measures of brain atrophy in older adults.

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Canine cognitive dysfunction (CCD) patients have reduced total hippocampal volume compared with aging control dogs: a comparative MRI study

10.1101/2020.01.27.920918 ◽

2020 ◽

Author(s):

Curtis Wells Dewey ◽

Mark Rishniw ◽

Simon Platt ◽

Kelsey Robinson ◽

Joseph Sackman ◽

...

Keyword(s):

Cognitive Dysfunction ◽

Hippocampal Volume ◽

Hippocampal Atrophy ◽

Pathological Feature ◽

Volumetric Mri ◽

Total Brain Volume ◽

Brain Volumes ◽

Disease Mechanisms ◽

Total Brain ◽

Mri Study

AbstractHippocampal atrophy is a key pathologic and MRI feature of human Alzheimer’s disease (AD). Hippocampal atrophy has not been documented via MRI in canine cognitive dysfunction (CCD), which is considered the dog model of human AD. The purpose of this retrospective comparative volumetric MRI study was to compare total hippocampal volumes between successfully aging (control) dogs and dogs diagnosed with CCD. Mimics® software was used to derive total hippocampal volumes and total brain volumes from the MRI studies of 42 aging dogs (≥ 9 years): 16 dogs diagnosed with CCD and 26 successfully aging controls. Total hippocampal volume normalized to total brain volume was significantly less for CCD patients compared with control dogs (p=0.04). The results of this study suggest that-similar to human AD-hippocampal atrophy is a pathological feature of CCD. This finding has potential importance for both investigating disease mechanisms related to dementia as well as future hippocampal-targeted therapies.

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Plasma EFEMP1 Is Associated with Brain Aging and Dementia: The Framingham Heart Study

Journal of Alzheimer s Disease ◽

10.3233/jad-215053 ◽

2021 ◽

pp. 1-10

Author(s):

Emer R. McGrath ◽

Jayandra J. Himali ◽

Daniel Levy ◽

Qiong Yang ◽

Charles S. DeCarli ◽

...

Keyword(s):

Brain Injury ◽

Test Performance ◽

Matrix Protein ◽

Brain Aging ◽

Structural Mri ◽

Premature Aging ◽

Extracellular Matrix Protein ◽

Brain Volumes ◽

Total Brain ◽

Increased Risk

Background: Epidermal growth factor containing fibulin extracellular matrix protein-1 (EFEMP1) has been associated with increased white matter hyperintensities (WMH) burden and disorders of premature aging and may have a shared pathophysiological role in the development of WMH and dementia. Objective: To determine the association between plasma EFEMP1 levels and MRI markers of vascular brain injury and incident all-cause and Alzheimer’s disease (AD) dementia. Methods: We measured plasma EFEMP1 levels in 1597 [53% women, mean age 68.7 (SD 5.7) years] dementia-free Framingham Offspring cohort participants between 1998–2001 and subsequently followed them for incident dementia. Secondary outcomes included stroke, structural MRI brain measures and neurocognitive test performance. Results: During a median 11.8 [Q1, Q3 : 7.1, 13.3] year follow-up, 131 participants developed dementia. The highest quintile of plasma EFEMP1, compared to the bottom four quintiles, was associated with an increased risk of time to incident all-cause dementia (HR 1.77, 95% CI 1.18–2.64) and AD dementia (HR 1.76, 95% CI 1.11–2.81) but not with markers of vascular brain injury (WMH, covert brain infarcts or stroke). Higher circulating EFEMP1 concentrations were also cross-sectionally associated with lower total brain (β±SE, –0.28±0.11, p = 0.01) and hippocampal volumes (–0.006±0.003, p = 0.04) and impaired abstract reasoning (Similarities test, –0.18±0.08, p = 0.018 per standard deviation increment in EFEMP1). Conclusion: Elevated circulating EFEMP1 is associated with an increased risk of all-cause and AD dementia, smaller hippocampal and total brain volumes, and poorer cognitive performance. EFEMP1 may play an important biological role in the development of AD dementia. Further studies to validate these findings are warranted.

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Abstract P73: Imaging Markers of Brain Frailty and Outcome in Patients With Acute Ischemic Stroke

Stroke ◽

10.1161/str.52.suppl_1.p73 ◽

2021 ◽

Vol 52 (Suppl_1) ◽

Author(s):

Ning Bu ◽

Mohamed S Khlif ◽

Robin Lemmens ◽

Anke Wouters ◽

Jochen B Fiebach ◽

...

Keyword(s):

Ischemic Stroke ◽

Acute Ischemic Stroke ◽

Functional Outcome ◽

Small Vessel Disease ◽

Brain Volumes ◽

Excellent Outcome ◽

Total Brain ◽

Brain Parenchymal Fraction ◽

Imaging Markers ◽

Brain Parenchymal

Background and purpose: Functional outcome after stroke may be related to preexisting brain health. Several imaging markers of brain frailty have been described including brain atrophy and markers of small vessel disease. We investigated the association of these imaging markers with functional outcome after acute ischemic stroke. Methods: We retrospectively studied patients with acute ischemic stroke enrolled in the AXIS-2 trial, an international, multicenter, randomized controlled clinical trial of Granulocyte Colony Stimulating Factor versus placebo. We assessed the ratio of brain parenchymal volume to total intracerebral volumes (i.e., the brain parenchymal fraction [BPF]) and total brain volumes from routine baseline MRI data obtained within 9 hours of symptom onset using the unified segmentation algorithm in SPM12. Enlarged perivascular spaces (EPVS), white matter hyperintensities (WMH), lacunes as well as a small vessel disease (SVD) burden were rated visually. Functional outcomes (modified Rankin Scale [mRS] score) at day 90 were determined. Logistic regression was used to test associations between brain imaging features and functional outcomes. As there was no significant effect of G-CSF on any outcomes in AXIS-2, placebo and active groups were combined for these analyses. Results: We enrolled 259 patients with a mean age of 69±12 years and 46 % were female. Increased BPF was associated with higher odds of excellent outcome (OR per percent increase: 1.081, 95%CI: 1.012-1.155). Total brain volumes and SVD burden were not associated with functional outcome. An interaction between BPF and large vessel occlusion on excellent outcome was not observed. Conclusions: Global brain health, as assessed by brain parenchymal fraction on magnetic resonance imaging, is associated with excellent functional outcome after ischemic stroke. Clinical Trial Registration: URL: http://www.clinicaltrials.gov . Unique identifier: NCT00927836.

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Association of Social Engagement with Brain Volumes Assessed by Structural MRI

Journal of Aging Research ◽

10.1155/2012/512714 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 12

Author(s):

Bryan D. James ◽

Thomas A. Glass ◽

Brian Caffo ◽

Jennifer F. Bobb ◽

Christos Davatzikos ◽

...

Keyword(s):

Social Engagement ◽

Structural Mri ◽

Population Based ◽

Magnetic Resonance Images ◽

Intracranial Volume ◽

Linear Regression Models ◽

Brain Volumes ◽

Total Brain ◽

Summary Scale ◽

Control Versus

We tested the hypothesis that social engagement is associated with larger brain volumes in a cohort study of 348 older male former lead manufacturing workers () and population-based controls (), age 48 to 82. Social engagement was measured using a summary scale derived from confirmatory factor analysis. The volumes of 20 regions of interest (ROIs), including total brain, total gray matter (GM), total white matter (WM), each of the four lobar GM and WM, and 9 smaller structures were derived from T1-weighted structural magnetic resonance images. Linear regression models adjusted for age, education, race/ethnicity, intracranial volume, hypertension, diabetes, and control (versus lead worker) status. Higher social engagement was associated with larger total brain and GM volumes, specifically temporal and occipital GM, but was not associated with WM volumes except for corpus callosum. A voxel-wise analysis supported an association in temporal lobe GM. Using longitudinal data to discern temporal relations, change in ROI volumes over five years showed null associations with current social engagement. Findings are consistent with the hypothesis that social engagement preserves brain tissue, and not consistent with the alternate hypothesis that persons with smaller or shrinking volumes become less socially engaged, though this scenario cannot be ruled out.

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Adiposity is related to cerebrovascular and brain volumetry outcomes in the RUN DMC study

Neurology ◽

10.1212/wnl.0000000000008002 ◽

2019 ◽

Vol 93 (9) ◽

pp. e864-e878 ◽

Cited By ~ 4

Author(s):

Ilse A.C. Arnoldussen ◽

Deborah R. Gustafson ◽

Esther M.C. Leijsen ◽

Frank-Erik de Leeuw ◽

Amanda J. Kiliaan

Keyword(s):

White Matter ◽

Brain Imaging ◽

Gray Matter ◽

Diffusion Tensor ◽

Hippocampal Volume ◽

White Matter Hyperintensity ◽

Brain Volumes ◽

Brain Volumetry ◽

Total Brain

ObjectiveAdiposity predictors, body mass index (BMI), waist circumference (WC), and blood leptin and total adiponectin levels were associated with components of cerebral small vessel disease (CSVD) and brain volumetry in 503 adults with CSVD who were ≥50 years of age and enrolled in the Radboud University Nijmegen Diffusion Tensor and Magnetic Resonance Imaging Cohort (RUN DMC).MethodsRUN DMC participants were followed up for 9 years (2006–2015). BMI, WC, brain imaging, and dementia diagnoses were evaluated at baseline and follow-up. Adipokines were measured at baseline. Brain imaging outcomes included CSVD components, white matter hyperintensities, lacunes, microbleeds, gray and white matter, hippocampal, total brain, and intracranial volumes.ResultsCross-sectionally among men at baseline, higher BMI, WC, and leptin were associated with lower gray matter and total brain volumes, and higher BMI and WC were associated with lower hippocampal volume. At follow-up 9 years later, higher BMI was cross-sectionally associated with lower gray matter volume, and an obese WC (>102 cm) was protective for ≥1 lacune or ≥1 microbleed in men. In women, increasing BMI and overweight or obesity (BMI ≥25 kg/m2 or WC >88 cm) were associated with ≥1 lacune. Longitudinally, over 9 years, a baseline obese WC was associated with decreasing hippocampal volume, particularly in men, and increasing white matter hyperintensity volume in women and men.ConclusionsAnthropometric and metabolic adiposity predictors were differentially associated with CSVD components and brain volumetry outcomes by sex. Higher adiposity is associated with a vascular-neurodegenerative spectrum among adults at risk for vascular forms of cognitive impairment and dementias.

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Similar foraging energetics of two sympatric albatrosses despite contrasting life histories and wind-mediated foraging strategies

Journal of Experimental Biology ◽

10.1242/jeb.228585 ◽

2020 ◽

Vol 223 (23) ◽

pp. jeb228585 ◽

Cited By ~ 1

Author(s):

Caitlin E. Kroeger ◽

Daniel E. Crocker ◽

Rachael A. Orben ◽

David R. Thompson ◽

Leigh G. Torres ◽

...

Keyword(s):

Energy Balance ◽

Life Histories ◽

Behavioral Plasticity ◽

Environmental Changes ◽

Behavioral Flexibility ◽

Mass Gain ◽

Central Place ◽

Foraging Strategies ◽

Wind Speeds ◽

Ocean Environment

ABSTRACTUnderstanding the environmental and behavioral factors that influence how organisms maintain energy balance can inform us about their potential resiliency to rapid environmental changes. Flexibility in maintaining energy balance is particularly important to long-lived, central-place foraging seabirds that are constrained when locating food for offspring in a dynamic ocean environment. To understand the role of environmental interactions, behavioral flexibility and morphological constraints on energy balance, we used doubly labeled water to measure the at-sea daily energy expenditure (DEE) of two sympatrically breeding seabirds, Campbell (Thalassarche impavida) and grey-headed (Thalassarchechrysostoma) albatrosses. We found that species and sexes had similar foraging costs, but DEE varied between years for both species and sexes during early chick rearing in two consecutive seasons. For both species, greater DEE was positively associated with larger proportional mass gain, lower mean wind speeds during water take-offs, greater proportions of strong tailwinds (>12 m s−1), and younger chick age. Greater proportional mass gains were marginally more costly in male albatrosses that already have higher wing loading. DEE was higher during flights with a greater proportion of strong headwinds for grey-headed albatrosses only. Poleward winds are forecasted to intensify over the next century, which may increase DEE for grey-headed albatrosses that heavily use this region during early chick rearing. Female Campbell albatrosses may be negatively affected by forecasted slackening winds at lower latitudes due to an expected greater reliance on less energy efficient sit-and-wait foraging strategies. Behavioral plasticity associated with environmental variation may influence future population responses to climate change of both species.

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Ontogenetic Changes in Web Design in Two Orb-Web Spiders

Ethology ◽

10.1111/j.1439-0310.2010.01760.x ◽

2010 ◽

Vol 116 (6) ◽

pp. 535-545 ◽

Cited By ~ 32

Author(s):

Thomas Hesselberg

Keyword(s):

Web Design ◽

Ontogenetic Changes ◽

Orb Web ◽

Orb Web Spiders

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