Recent studies have established the moment-to-moment turnover of the blood-oxygen-level-dependent signal (TBOLD) at resting state as a key measure of local cortical brain function. Here, we sought to extend that line of research by evaluating TBOLD in 70 cortical areas with respect to corresponding brain volume, age, and sex across the lifespan in 1,344 healthy participants including 633 from the Human Connectome Project (HCP) - Development cohort (294 males and 339 females, age range 8-21 yr) and 711 healthy participants from HCP-Aging cohort (316 males and 395 females, 36-90 yr old). In both groups, we found that 1) TBOLD increased with age, 2) volume decreased with age, and 3) TBOLD and volume were highly significantly negatively correlated, independent of age. The inverse association between TBOLD and volume was documented in nearly all 70 brain areas and for both sexes, with slightly stronger associations documented for males. The strong correspondence between TBOLD...
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We assessed changes in gray matter volume (GMV) of nine subcortical regions (accumbens, amygdala, brainstem, caudate, cerebellar cortex, pallidum, putamen, thalamus, and ventral diencephalon) across the lifespan in a large sample of participants in the Human Connectome Project (n = 2,458, 5-90 yr old, 1,113 males and 1,345 females). 3T MRI data were acquired using a harmonized protocol and were processed in an identical way for all brains. GMVs of individual regions were adjusted for estimated total intracranial volume and regressed against age. We found highly statistically significant changes in GMV with age (P < 0.001) that were distinct among areas and mostly consistent between sexes, as follows. 1) The GMVs of accumbens, caudate, putamen, and cerebellum decreased with age in a linear fashion. The rate of decrease was steeper in males than in females for all regions. 2) The GMVs of the amygdala, pallidum, thalamus, ventral diencephalon, and brainstem changed with age in a quadratic fashion, i.e., increasing first and decreasing afterward. The estimated age at the peak (vertex) of the parabola was 51.8 yr for the brainstem and 28.0-37.9 yr for the other regions. The peak occurred earlier in males than in females, by an average of 8 yr, with the exception of the brainstem, where the age at the peak was very similar in both sexes. These results confirm previous findings and offer new insights into region-specific age-related changes in subcortical brain GMVs.

Dr. Apostolos P. Georgopoulos joins the JNP Micro Podcasts "Four Questions" to discuss the Brain Sciences CenterBrain Sciences Center (BSC)'s recently published "Changes of cortical gray matter volume during development: a Human Connectome Project study."

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We assessed changes in gray matter volume of 35 cerebrocortical regions in a large sample of participants in the Human Connectome Project-Development (n = 649, 6-21 yr old, 299 males and 350 females). The same protocol for MRI data acquisition and processing was used for all brains. Volumes of individual areas were adjusted for estimated total intracranial volume and linearly regressed against age. We found changes of volume with age that were distinct among areas and consistent between sexes, as follows: 1) the overall cortical volume decreased significantly with age; 2) the volumes of 30/35 areas also decreased significantly with age; 3) the volumes of the hippocampal cortex (hippocampus, parahippocampal, and entorhinal) and that of pericalcarine cortex did not show significant age-related changes; and 4) the volume of the temporal pole increased significantly with age. The rates of volume reduction with age did not differ significantly between the two sexes, except...
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It is known that brain volume decreases with age. Here, we assessed the rate of this decrease in gray matter volume of 35 cortical regions in a large sample of healthy participants (n = 712, age range 36-90 yr) of the Human Connectome Project-Aging. We evaluated the difference in this rate between men (n = 316) and women (n = 396) and found that the volumes of cortical areas decreased by an average of 5.25%/decade, with the highest rate of decrease observed in the rostral anterior cingulate cortex (7.28%/decade). The rate of decrease was higher in men than in women in general and in 30/35 (85.7%) areas in particular, involving most prominently the cingulate lobe. These findings could serve as a normative reference for clinical conditions that manifest with abnormal brain atrophy.

The moment-to-moment variation of neurovascular coupling in the brain was determined by computing the moment-to-moment turnover of the blood-oxygen-level-dependent signal (TBOLD) at resting state. Here we show that 1) TBOLD is heritable, 2) its heritability estimates are highly correlated between left and right hemispheres, and 3) the degree of its heritability is determined, in part, by the anatomical proximity of the brain areas involved. We also show that the regional distribution of TBOLD in the cortex is significantly associated with that of the vesicular acetylcholine transporter. These findings establish that TBOLD as a key heritable measure of local cortical brain function captured by neurovascular coupling.

We report on the functional connectivity (FC), its intraclass correlation (ICC), and heritability among 70 areas of the human cerebral cortex. FC was estimated as the Pearson correlation between averaged prewhitened Blood Oxygenation Level-Dependent time series of cortical areas in 988 young adult participants in the Human Connectome Project. Pairs of areas were assigned to three groups, namely homotopic (same area in the two hemispheres), ipsilateral (both areas in the same hemisphere), and heterotopic (nonhomotopic areas in different hemispheres). ICC for each pair of areas was computed for six genetic groups, namely monozygotic (MZ) twins, dizygotic (DZ) twins, singleton siblings of MZ twins (MZsb), singleton siblings of DZ twins (DZsb), non-twin siblings (SB), and unrelated individuals (UNR). With respect to FC, we found the following. (a) Homotopic FC was stronger than ipsilateral and heterotopic FC; (b) average FCs of left and right cortical areas were highly and positively correlated; and (c)...
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Cortical inhibition is theorized to reflect an underlying property of human brain function, sharpening tuning and shaping connectivity. Although age and sex effects on large-scale resting-state brain connectivity have been well documented, effects on local cortical inhibition have received relatively limited attention. Here, we evaluated age and sex effects on presumed local inhibitory interactions in 6 lateral cortical areas using resting-state Functional Magnetic Resonance ImagingFunctional Magnetic Resonance Imaging (fMRI)A functional neuroimaging procedure using MRI technology that measures brain activity by detecting changes associated with blood flow. This technique relies on the fact that cerebral blood flow and neuronal activation are coupled. When an area of the brain is in use, blood flow to that region also increases.[citation needed] The primary form of fMRI uses the blood-oxygen-level dependent (BOLD) contrast, discovered by Seiji Ogawa. This is a type of specialized brain and body scan used to map neural activity in the brain or spinal cord of humans or other animals by imaging the change in blood flow (hemodynamic response) related to energy use by brain cells. Since the early 1990s, fMRI has come to dominate brain mapping research because it does not require people to undergo shots, surgery, or to ingest substances, or be exposed to ionising radiation, etc. data acquired from 1054 young adults who participated in the Human Connectome Project. For each area, all possible pairwise crosscorrelations between prewhitened blood oxygenation level-dependent (BOLD) time series were calculated, and the highest value (CCmax) was retained to determine the mean and percentage of negative and positive CCmax. Here, we focused on the percentage of negative CCmax which we referred to as presumed "percent inhibition". The results documented regional differences in percent inhibition as well as age and sex effects, such that women's brains were...
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Here we report on the heritability and Intraclass Correlation Coefficients (ICCs) of brain volumes in 1,103 young healthy adults with mean age 29.2 years. Among them are: 153 monozygotic (MZ) twin pairs and 86 dizygotic (DZ) twin pairs, 133 non-twin siblings of MZ twins, 76 non-twin siblings of DZ twins, 335 siblings, and 81 unrelated individuals. ICCs were calculated between pairs of the following genetic groups: (1) MZ twins; (2) DZ twins; (3) MZ twins—their singleton siblings; (4) DZ twins—their singleton siblings; (5) siblings (SB); and (6) unrelated individuals (NR). We studied 4 brain groups: global, lobar, subcortical, and cortical brain regions. For each of 4 brain groups we found the same order of ICCs ranging from the highest values for MZ twins, statistically significantly smaller for the DZ twins and 3 sibling groups, and practically zero for NR. The DZ twins and 3 sibling groups were not different. No hemispheric...
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The Human Connectome Project (HCP) provides a rich dataset of quantitative and domain-specific behavioral measures from twins and extensive family structures. This makes the dataset a unique and a valuable resource to investigate heritability and determine individual differences. Using a set of measures of behavioral domains (motor, emotion, personality, sensory, and cognition), we estimated the intraclass correlations (ICCs) and heritability of 56 behavioral measures for 4 genetically identified groups of participants: monozygotic (MZ) twins, dizygotic (DZ) twins, non-twin siblings (SB), and unrelated individuals (NR). The ICCs range varied among behavioral domains but systematically so among the four genetic groups. We found the same rank order of ICCs, from the highest values for MZ twins, statistically significantly smaller for the DZ twins and sibling group (compared to MZ), and close to zero for NR. The mean heritability values of the five behavioral domains were: cognition h² = 0.405, emotion h² = 0.316, motor h² = 0.138, personality h² = 0.444,...
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We focus on the origin of Post-traumatic Stress DisorderPost-traumatic Stress Disorder (PTSD)A complex psychiatric syndrome that develops in response to trauma exposure. Individuals with PTSD experience intrusive recollections or reexperiencing of the traumatic event, avoidance of trauma reminders, emotional numbing, and hyperarousal. In addition, PTSD is associated with high rates of concomitant physical and mental health problems, increased health care use, and impairment in social and occupational functioning. Almost 7% of the general population and up to 30% of veterans meet lifetime criteria for PTSD. Indeed, PTSD is one of the most common psychiatric disorders, representing a significant and costly public health concern., on the meural mechanisms underlying its development. Specifically, we propose a two-hit model for PTSDPost-traumatic Stress Disorder (PTSD)A complex psychiatric syndrome that develops in response to trauma exposure. Individuals with PTSD experience intrusive recollections or reexperiencing of the traumatic event, avoidance of trauma reminders, emotional numbing, and hyperarousal. In addition, PTSD is associated with high rates of concomitant physical and mental health problems, increased health care use, and impairment in social and occupational functioning. Almost 7% of the general population and up to 30% of veterans meet lifetime criteria for PTSD. Indeed, PTSD is one of the most common psychiatric disorders, representing a significant and costly public health concern. development, with the following components:

• the 1st hit is a neuroimmune challenge, as a preexisting condition
• the 2nd hit is intense glutamatergic neurotrasmission, induced by the traumatic event.

Such a "locked-in" network underlies the intrusive re-experiencing in PTSDPost-traumatic Stress Disorder (PTSD)A complex psychiatric syndrome that develops in response to trauma exposure. Individuals with PTSD experience intrusive recollections or reexperiencing of the traumatic event, avoidance of trauma reminders, emotional numbing, and hyperarousal. In addition, PTSD is associated with high rates of concomitant physical and mental health problems, increased health care use, and impairment in social and occupational functioning. Almost 7% of the general population and up to 30% of veterans meet lifetime criteria for PTSD. Indeed, PTSD is one of the most common psychiatric disorders, representing a significant and costly public health concern. and maintains associated symptomatology, such as fear and avoidance