Introduction
Term | Explanation |
---|---|
Structural connectivity | |
Cortical thickness | A one-dimensional measure describing the thickness of the cortex. Cortical thickness is typically calculated as the as the distance between the grey/white matter boundary to the grey matter/CSF boundary. This measure is calculated at thousands of points along the cortical surface and an average measure can be provided for the entire brain or a specified region of interest. |
Surface area | A two-dimensional measure that represents the size of the total outer surface (including the folds an fissures) of the cortex. This measure can be provided for the entire brain or for any given region of interest. |
Volume | A three-dimensional measure of the size (volume) of the entire brain or any given brain region or structure of interest. Volume is equivalent to the product of cortical thickness and surface area. |
Grey matter (GM) density | A measure of the local concentration of grey matter. |
White matter (WM) density | A measure of the local concentration of white matter. |
Structural connectivity | |
Diffusion Tensor Imaging (DTI) | An MRI technique that enables the measurement of the diffusion properties of water molecules in brain tissues. Since the diffusion properties of water differ between different types of brain tissues, DTI can be used to measure the microstructural properties of these tissues. The most common use of DTI is to evaluate white matter tracts, which have greater diffusion along the WM tract compared to tangential to the WM tracts. |
Fractional Anisotropy (FA) | A rotational-invariant scalar measure of water molecule diffusion in tissue. FA is a value between zero and one that describes the amount of restriction in diffusion. A value of zero means that the diffusion of water molecules is unrestricted (isotropic), free to diffuse in all directions. A value of one means that diffusion occurs only along one axis and is fully restricted (anisotropic). |
Radial Diffusivity (RD) | Similar to FA, RD is a scalar measure describing water molecule diffusion in tangential to the principal direction of diffusion. RD is the average of the diffusivities of the two perpendicular axes. |
Magnetization Transfer Ratio (MTR) | An MRI measure providing an estimate of structural integrity and is considered a technique for measuring myelination of neurons. MT imaging is based on interactions between protons freely moving in a water pool and those bound to macromolecules, thus restricted in motion. By using MR sequences with and without an off-resonance saturation pulse, MT imaging allows calculation of an index, the MTR. The MTR is the difference in signal intensity with or without the off-resonance saturation pulse. |
Functional connectivity | |
Functional MRI (fMRI) | An MRI technique that measures the blood oxygen level dependent (BOLD) signal in the brain. FMRI provides information on brain activity and the connectivity between different regions (functional connectivity). |
Blood Oxygen Level Dependent (BOLD) signal | MRI contrast that relies on the signal differences between oxygenated and deoxygenated hemoglobin. When there is a change in neuronal activity in a certain brain region, more oxygenated hemoglobin is shunted to that region, giving rise to a measureable change in the local ratio of oxy- to deoxyhemoglobin. This provides a local marker of brain activity. |
Analyses techniques | |
Voxel Based Morphometry (VBM) analysis | An MRI analysis technique that involves spatially normalizing all the brain images into a standard space (often a brain atlas). Then statistics are performed between groups (or continuous) on a voxel-by-voxel basis. Due to large number of voxels tested, correction for multiple testing is required. |
Region Of Interest (ROI) analysis | An MRI analysis technique that requires the identification of regions of interest and restricting the analyses to these specific regions. ROI-based techniques are utilized in both structural and functional imaging. |
Heritability of Brain Structure in Children
Neonates
Primary School Age
The Dutch Sample
The Canadian Sample
The USA (NIMH) Sample
Study | Sample | N pairs | Brain measure and region | Heritability estimate | ||
---|---|---|---|---|---|---|
Brouwer et al. 2010
| CHILDREN Mean age 9.2 (0.1) | MZM 41, MZF 42, DZM 38, DZF 39, DOS 26 |
Diffusion Tensor Imaging & Magnetization Transfer Imaging
|
ACE model
|
ACE model
|
ACE model
|
Magnetization transfer ratio
|
Fractional anisotropy
|
Radial diffusivity
| ||||
Genu of corpus callosum | 31 % | 32 % | 32 % | |||
Splenium of corpus callosum | 47 % | 15 % | 33 % | |||
Left uncinated fasciculus | 20 % | 27 % | 29 % | |||
Right uncinated fasciculus | 14 % | 18 % | 17 % | |||
Left superior longitudinal fasciculus | 61 % | 30 % | 64 % | |||
Right superior longitudinal fasciculus | 50 % | 21 % | 27 % | |||
Gilmore et al. 2010
| CHILDREN 288 days (neonatal) | MZM 36, MZF 46, DZM 54, DZF 46, single twins 35 |
Volume (Region of Interest)
|
ACE model
|
ACE model
| |
GM
|
WM
| |||||
Total | 56 % | 85 % | ||||
Cortical | 58 % | 85 % | ||||
SubCortical | 62 % | − | ||||
Prefrontal | 30 % | 53 % | ||||
Frontal | 31 % | 84 % | ||||
Parietal | 65 % | 72 % | ||||
Occipital | 57 % | 86 % | ||||
Right Hemisphere | 44 % | 82 % | ||||
Left Hemisphere | 71 % | 79 % | ||||
Volume (Region Of Interest)
|
Total
| |||||
ICV | 73 % | |||||
Lateral ventricle | 71 % | |||||
Cerebellum | 17 % | |||||
CSF | 63 % | |||||
Prefrontal | 42 % | |||||
Frontal | 64 % | |||||
Parietal | 74 % | |||||
Occipital | 74 % | |||||
RHemisphere | 64 % | |||||
L hemisphere | 74 % | |||||
Corpus callosum | 4 % | |||||
Heuvel van den, et al. 2013 | CHILDREN Mean age 12.1 (0.3) | MZM 9, MZF 12, DZM 4, DZF 4, DOS 8 |
Functional connectivity (fMRI)
| AE model | ||
Normalized path length (i.e., the level of communication efficiency): 42 % | ||||||
Connectivity (i.e., the level of coherence in number of connections): 0 % | ||||||
Normalized clustering (i.e., level of overlap in local clustering): 0 % | ||||||
Lenroot et al. 2009
| CHILDREN Age range 5–19 | MZM 117, MZF 97, DZM 53, DZF 41, siblings 64, singletons 228 |
Cortical thickness
|
ACE model
|
ACE model
| |
LEFT
|
RIGHT
| |||||
Sup. Frontal gyrus | 51 % | 45 % | ||||
Mid. Frontal gyrus | 38 % | 43 % | ||||
Inf. Frontal gyrus | 44 % | 52 % | ||||
Precentral gyrus | 52 % | 43 % | ||||
Sup temporal gyrus | 40 % | 41 % | ||||
Mid. temporal gyrus | 39 % | 33 % | ||||
Inf. Temporal gyrus | 47 % | 38 % | ||||
Peper et al. 2009
| CHILDREN Mean age 9.2 (0.1) | MZM 22, MZF 23, DZM 22, DZF 21, DOS 19 |
Volume (Region of Interest)
|
ACE model
| ||
ICV | 91 % | |||||
Total brain | 94 % | |||||
Lateral ventricles | 35 % | |||||
GM | 77 % | |||||
WM | 84 % | |||||
Cerebellum | 88 % | |||||
GM density (VBM)
|
LEFT
|
RIGHT
| ||||
Mid. temporal gyrus | − | 83 % | ||||
Sup. frontal gyrus | 82 % | − | ||||
Amygdala | 83 % | − | ||||
WM density (VBM)
|
LEFT
|
RIGHT
| ||||
Sup fronto-occipital fascicle | − | 67 % | ||||
Sup fronto-occipital fascicle | 82 % | 93 % | ||||
Sub. Longitudinal fascicle | − | 91 % | ||||
Sub. Longitudinal fascicle | 88 % | 76 % | ||||
Genu corpus callosum | 80 % | 86 % | ||||
Posterior cingulum | 86 % | |||||
Schmitt et al. 2007
| CHILDREN Age range 5–18 | MZM 74, MZF 53, DZM 18, DZF 12, singleton 158 |
Volume (Region of Interest)
|
ACE model
| ||
Cerebrum | 68 % | |||||
Lateral ventricles | 17 % | |||||
Corpus callosum | 65 % | |||||
Thalamus | 42 % | |||||
Basal ganglia | 64 % | |||||
Cerebellum | 24 % | |||||
Wallace et al. 2006
| CHILDREN Age range 5–18 | MZM 52, MZF 38, DZM 22, DZF 15, singleton 158 |
Volume (Region of Interest)
|
ACE model
|
ACE model
|
ACE model
|
TOTAL
|
GM
|
WM
| ||||
Cerebral | 89 % | 82 % | 85 % | |||
Frontal | 84 % | 77 % | 84 % | |||
Parietal | 86 % | 78 % | 85 % | |||
Temporal | 88 % | 80 % | 82 % | |||
Caudate nucleus | 80 % | |||||
Corpus callosum | 85 % | |||||
Lateral ventricles | 31 % | |||||
Cerebellum | 49 % | |||||
Yoon et al. 2010
| CHILDREN Mean age 8.4 (0.2) | MZM 22, MZF 35, DZM 15, DZF 20 |
Volume (Region of Interest)
|
ACE model
|
ACE model
|
ACE model
|
TOTAL
|
LEFT
|
RIGHT
| ||||
Whole brain | 71 % | |||||
Whole brain GM | 65 % | 67 % | 59 % | |||
Whole brain WM | 80 % | 81 % | 81 % | |||
Cortical GM | 65 % | 65 % | 56 % | |||
Subcortical GM | 41 % | 41 % | 32 % | |||
Cerebrum | 71 % | 78 % | 51 % | |||
Ventricle | 48 % | 54 % | 24 % | |||
Corpus Callosum | 51 % | − | − | |||
Cortical thickness
|
LEFT
|
RIGHT
| ||||
Whole | 71 % | 56 % | ||||
Frontal | 72 % | 54 % | ||||
Temporal | 56 % | 53 % | ||||
Parietal | 59 % | 46 % | ||||
Occipital | 67 % | 61 % | ||||
Yoon et al. 2011
| CHILDREN Mean age 8.4 (0.2) | MZM 22, MZF 35, DZM 15, DZF 20 |
Volume (Region of Interest)
|
ACE model
|
ACE model
|
ACE model
|
TOTAL
|
LEFT
|
RIGHT
| ||||
Cerebrum | 70 % | 67 % | 58 % | |||
Total GM | 67 % | 62 % | 57 % | |||
Total WM | 73 % | 72 % | 62 % | |||
Corpus callosum | 79 % | − | − | |||
Frontal GM | − | 76 % | 61 % | |||
Frontal WM | − | 78 % | 62 % | |||
Temporal GM | − | 59 % | 40 % | |||
Temporal WM | − | 62 % | 43 % | |||
Parietal GM | − | 59 % | 43 % | |||
Parietal WM | − | 61 % | 54 % | |||
Occipital GM | − | 53 % | 43 % | |||
Occipital WM | − | 50 % | 46 % | |||
Putamen | − | 79 % | 77 % | |||
Thalamus | − | 59 % | 47 % | |||
Caudatus | − | 49 % | 26 % | |||
Globus pallidus | − | 81 % | 76 % | |||
Lateral ventricle | − | 49 % | 64 % | |||
Cerebellum | − | 69 % | 42 % |
Heritability of Brain Structure and Function in Adults
Brain Structure
Dutch Twin Sibling Sample
The VETSA Sample
Brain Function
Study | Sample | N pairs | Brain measure and region | Heritability estimate | |||
---|---|---|---|---|---|---|---|
Baaré et al. 2001
| ADULTS Age range 28–34 | MZM 33, MZF 21, DZM 17, DZF 20, DOS 21, singles M 19, F 15 |
Volume (Region of Interest)
|
AE model
| |||
ICV | 88 % | ||||||
Total brain | 90 % | ||||||
GM | 82 % | ||||||
WM | 87 % | ||||||
Bartley et al. 1997
| ADULTS Age range 19–54 | MZ 10, DZ 9 |
Volume (Region of Interest)
|
AE model
| |||
Total brain | 94 % | ||||||
Left hemisphere | 94 % | ||||||
Right hemisphere | 94 % | ||||||
Blokland et al. 2011
| ADULTS Age range 21–27 | MZ 75, DZ 66 |
Functional MRI (fMRI)
|
ACE model
| |||
Voxel wise, working memory task related brain response | 0–65 % | ||||||
Chen et al. 2012
| ADULTS Age range 51–59 | MZM 110, DZM 93 |
Surface Area
|
AE model
|
AE model
| ||
LEFT
|
RIGHT
| ||||||
Motor-premotor cortex | 43 % | 39 % | |||||
Dorsolateral prefrontal cortex | 40 % | 30 % | |||||
Dorsomedial frontal cortex | 42 % | 38 % | |||||
Orbitofrontal cortex | 33 % | 38 % | |||||
Pars opercularis | 36 % | 30 % | |||||
Superior temporal cortex | 34 % | 28 % | |||||
Posterolateral temporal cortex | 32 % | 37 % | |||||
Anteromedial temporal cortex | 37 % | 40 % | |||||
Inferior parietal cortex | 30 % | 36 % | |||||
Superior parietal cortex | 38 % | 37 % | |||||
Precuneus | 49 % | 32 % | |||||
Occipital cortex | 48 % | 37 % | |||||
Eyler et al. 2011
| ADULTS Age range51–59 | MZM 110, DZM 92 |
Surface Area
|
ACE model
|
ACE model
| ||
LEFT
|
RIGHT
| ||||||
Frontal | 76 % | 54 % | |||||
Parietal | 55 % | 37 % | |||||
Occipital | 59 % | 31 % | |||||
Lat. Temporal | 55 % | 33 % | |||||
Med. temporal | 20 % | 13 % | |||||
Cingulate | 26 % | 44 % | |||||
Heritability estimates adjusted for age, site and total surface area | |||||||
Glahn et al. 2010
| ADULTS Age range26–85 | Extended twin design. 29 large extended pedigrees, average family size 9 (5–32 people) 63 % F, 37 % M |
Functional connectivity (fMRI)
|
AE model
| |||
Posterior cingulate/precuneus | 42.3 % | ||||||
Medial prefrontal cortex | 37.6 % | ||||||
Left temporal-parietal region | 33.1 % | ||||||
Right temporal-parietal region | 42 % | ||||||
Left cerebellum | 10.4 % | ||||||
Right cerebellum | 30.4 % | ||||||
Cerebellar tonsil | 21.9 % | ||||||
Left parahippocampal gyrus | 27.3 % | ||||||
GM density (VBM)
| |||||||
Posterior cingulate/precuneus | 62.3 % | ||||||
Medial prefrontal cortex | 63.1 % | ||||||
Left temporal-parietal region | 38.7 % | ||||||
Right temporal-parietal region | 26.5 % | ||||||
Left cerebellum | 49.3 % | ||||||
Right cerebellum | 59.6 % | ||||||
Cerebellar tonsil | 27.1 % | ||||||
Left parahippocampal gyrus | 42 % | ||||||
Hulshoff Pol et al. 2006
| ADULTS Age range19–69 | MZM 33, MZF 21, DZM 17, DZF 20, DOS 21, siblings 34 |
GM density (VBM)
|
AE model
|
AE model
| ||
LEFT
|
RIGHT
| ||||||
Superior frontal a
| − | 80 % | |||||
Superior frontal | 76 % | 76 % | |||||
Medial frontal a
| − | 82 % | |||||
Medial frontal | 78 % | 83 % | |||||
Postcentral gyrus | 83 % | − | |||||
Posterior cingulate | 83 % | − | |||||
Heschl’s gyrus | 80 % | 77 % | |||||
Amygdala | 80 % | 55 % | |||||
Occipital cortex | 85 % | − | |||||
Parahippocampal | − | 69 % | |||||
WM density (VBM)
|
LEFT
|
RIGHT
| |||||
Superior occipitofrontal fascicle | 79 % | 77 % | |||||
Corpus callosum | 82 % | 80 % | |||||
Optic radiation | 69 % | 79 % | |||||
Corticospinal tract | 78 % | 79 % | |||||
a Two separate genetically determined areas were identified within the superior and medial frontal cortices in the right hemisphere | |||||||
Kremen et al. 2010b | ADULTS Age range51–59 | MZM 110, DZM 92 |
Volume (Region of Interest)
|
ACE model
|
ACE model
| ||
LEFT
|
RIGHT
| ||||||
Cerebral cortex | 77 % | 70 % | |||||
Cerebral WM | 76 % | 75 % | |||||
Cerebellar cortex | 64 % | 76 % | |||||
Cerebellar WM | 79 % | 81 % | |||||
Lateral ventricle | 76 % | 73 % | |||||
Matthews et al. 2007
| ADULTS Age range20–56 | MZF 10, DZF 10 |
Functional MRI (fMRI)
| ||||
Interference task related responses: | |||||||
Dorsal ACC | 38 % | ||||||
Ventral ACC | 0 % | ||||||
Posterior CC | 0 % | ||||||
Insula left | 0 % | ||||||
Insula right | 0 % | ||||||
Panizzon et al. 2009
| ADULTS Age range51–59 | MZM 110, DZM 92 |
Surface area Right
|
Surface area Left
|
Cortical thickness Right
|
Cortical thickness Left
| |
Frontal lobe | 81 % | 88 % | 70 % | 78 % | |||
Temporal lobe | 85 % | 87 % | 67 % | 63 % | |||
Parietal lobe | 77 % | 87 % | 74 % | 74 % | |||
Occipital lobe | 31 % | 64 % | 52 % | 71 % | |||
Lateral orbital frontal cortex | 35 % | 51 % | 55 % | 52 % | |||
Superior frontal gyrus | 67 % | 69 % | 65 % | 76 % | |||
Superior parietal gyrus | 50 % | 63 % | 67 % | 64 % | |||
Entorhinal cortex | 21 % | 16 % | 24 % | 20 % | |||
Parahippocampal gyrus | 20 % | 10 % | 58 % | 39 % | |||
Posterior central gyrus | 8 % | 61 % | 66 % | 59 % | |||
Posterior cingulate cortex | 33 % | 37 % | 51 % | 44 % | |||
Precuneus cortex | 31 % | 74 % | 53 % | 65 % | |||
Middle temporal gyrus | 48 % | 37 % | 41 % | 37 % | |||
Lateral occipital cortex | 3 % | 33 % | 55 % | 55 % | |||
Polk et al. 2007
| ADULTS Age range18–29 | MZM 13, DZM 11 |
Functional MRI (fMRI) Neural activation pattern in ventral visual cortex | NA, only twin correlations provided | |||
Posthuma et al. 2000
| ADULTS Age range29–34 | MZM 32, MZF 21, DZM 17, DZF 20, DOS 21, Siblings M 19, F 15 |
Volume (Region of Interest)
|
ACE model
| |||
ICS | 65 % | ||||||
Cerebellar | 81 % | ||||||
Scamvougeras et al. 2003
| ADULTS Age range16–41 | MZ 14, |
Surface Area
|
AE model
| |||
DZ 12 | Corpus callosum | 94 % | |||||
Thompson et al. 2001
| ADULTS Age range44–51 | MZ 10, |
GM density (VBM)
| ||||
DZ 10 | Whole-brain analysis - see Fig. 1
|
Heritability of Brain Structure in the Elderly
National Heart, Lung, and Blood Institute Twin Study
Study | Sample | N pairs | Brain measure and region | Heritability estimate | ||
---|---|---|---|---|---|---|
Carmelli et al. 1998
| ELDERLY Age range 71–72 | MZM 74, DZM 71 |
Volume (Region of Interest)
|
ACE model
| ||
ICV | 73 % | |||||
Brain parenchyma | 85 % | |||||
CSF | 72 % | |||||
WMH | 73 % | |||||
Geschwind et al. 2002
| ELDERLY Age range 68–74 | MZM 72, DZM 67 |
Volume (Region of Interest)
|
ACE model
|
ACE model
| |
LEFT
|
RIGHT
| |||||
Frontal | 52 % | 56 % | ||||
Parietal | 49 % | 45 % | ||||
Occipital | 29 % | 27 % | ||||
Temporal | 40 % | 52 % | ||||
Total hemispheric | 67 % | 64 % | ||||
Pfefferbaum et al. 2000
| ELDERLY Age range 68–78 | MZM 45, DZM 40 |
Surface Area
|
ACE model
| ||
Corpus callosum | 66 % | |||||
Height | 68 % | |||||
Length | 53 % | |||||
Genu | 52 % | |||||
Isthmus | 72 % | |||||
ADE model
|
ADE model
|
ADE model
| ||||
LEFT
|
RIGHT
| |||||
Lateral ventricle bilateral | 79 % | 22 % | 54 % | |||
Splenium | 58 % | |||||
Volume
|
ACE model
| |||||
ICV | 79 % | |||||
Pfefferbaum et al. 2001
| ELDERLY Mean age 75.7 (2.7) | MZM 15, DZM 18 |
Diffusion Tensor Imaging
|
AE model
| ||
Fractional anisotropy
| ||||||
Splenium fractional anisotropy | 67 % | |||||
Genu fractional anisotropy | 49 % | |||||
Surface Area
| ||||||
Mid sagittal callosal area | 85 % | |||||
Sullivan et al. 2001
| ELDERLY Age range 68–78 | MZM 44, DZM 40 |
Volume (Region of Interest)
|
ACE model
| ||
Bilateral hippocampus | 40 % | |||||
Bilateral temporal horn | 47 % | |||||
ICV | 79 % | |||||
Cross-sectional area
| ||||||
Corpus callosum | 66 % |
Longitudinal Studies
Primary School Age
The Dutch sample
The United States Sample
Adults
Dutch Twin Sibling Sample
Elderly
The VETSA Sample
Study | Sample | N pairs | Brain measure and region | Heritability estimate | |||
---|---|---|---|---|---|---|---|
Brans et al. 2010
| ADULTS Longitudinal, 5 years interval Age range 19–55 | MZM 52, MZF 25, DZM 31, DZF 29, DOS 12, siblings 22 |
Cortical thickness
|
AE model
|
AE model
|
AE model
|
AE model
|
LEFT
|
RIGHT
|
Change LEFT
|
Change RIGHT
| ||||
Frontal pole | 7 % | 50 % | 45 % | 43 % | |||
Medial frontal | − | 16 % | − | 56 % | |||
Parahippocampal | 7 % | 47 % | 48 % | 47 % | |||
Cortical thinning
|
LEFT
|
RIGHT
| |||||
Orbitofrontal | 55 % | − | 41 % | − | |||
Superior frontal | 58 % | − | 54 % | − | |||
Superior temporal/Heshl’s | 49 % | 13 % | 55 % | − | |||
Superior temporal | − | 50 % | − | 45 % | |||
Parietal lateral | 45 % | 13 % | 28 % | 45 % | |||
Lateral occipital | − | 15 % | − | 38 % | |||
Medial occipital | − | 52 % | 35 % | ||||
Brouwer et al. 2014
| ADULTS Longitudinal, 5 years interval Age range 19–55 | MZM 51, MZF 23, DZM 41, DZF 39, siblings 22 |
Volume
| AE model | AE model | AE model | |
TOTAL Change
|
GM Change
|
WM Change
| |||||
Total brain | 43 % | − | − | ||||
Cerebrum | 48 % | 10 % | 29 % | ||||
Cerebellum | 52 % | 25 % | 42 % | ||||
Lateral ventricle | 31 % | − | − | ||||
Third ventricle | 29 % | − | − | ||||
L brain | 45 % | − | − | ||||
L cerebrum | 52 % | 10 % | 23 % | ||||
L cerebellum | 13 % | − | − | ||||
L lateral ventricle | 28 % | − | − | ||||
R brain | 14 % | − | − | ||||
R cerebrum | 31 % | 16 % | 28 % | ||||
R cerebellum | 0 % | − | − | ||||
R lateral ventricle | 30 % | − | − | ||||
Surface area
| |||||||
Total | 33 % | − | − | ||||
Left Hemisphere | 36 % | − | − | ||||
Right Hemisphere | 24 % | − | − | ||||
Lessov-Schlaggar et al. 2012
| ELDERLY Longitudinal, 4 years interval Age range 68–77 | MZM 33, DZM 33 |
Volume (Region Of Interest)
| AE model | ACE model | ACE model | |
TIME 1
|
TIME 2
|
Change
| |||||
Total brain | 75 % | 48 % | 7 % | ||||
Total CSF | 73 % | 45 % | 6 % | ||||
Pfefferbaum et al. 2004
| ADULTS Longitudinal, 4 years interval | MZM 34, DZM 37 |
Corpus callosum size
| AE model | AE model | AE model | |
TIME 1
|
TIME 2
|
Change
| |||||
Age range unknown | Total area | 80 % | 85 % | 0 % | |||
Genu | 68 % | 81 % | 0 % | ||||
Body | 83 % | 81 % | 0 % | ||||
Splenium | 75 % | 83 % | 0 % | ||||
Height | 85 % | 83 % | 52 % | ||||
Length | 75 % | 73 % | 24 % | ||||
Ventricle size
|
TIME 1
|
TIME 2
| |||||
Total | 84 % | 78 % | 27 % | ||||
Right | 77 % | 74 % | 29 % | ||||
Left | 83 % | 76 % | 20 % | ||||
No significant change in heritability over 4 years time | |||||||
Schmitt et al. 2014
| CHILDREN Longitudinal, up to eight scans, mean interval 2.4 years | MZ 249, DZ 131 Siblings: 110 Singletons: 302 | No heritability [of change] estimates in numbers reported, see paper for visual representation of results | ||||
Age range | |||||||
9–12 | |||||||
Soelen van, et al. 2012 | CHILDREN Longitudinal, 3 years interval | TIME 1 MZ: 82, DZ: 108 |
Cortical thickness
| AE model | AE model | AE model | |
TIME 1
|
TIME 2
|
CHANGE
| |||||
Right medial prefrontal | 44 % | 42 % | 55 % | ||||
TIME 1: Mean age 9.2 (0.1) TIME 2: Mean age 12.0 (0.3) | TIME 2 MZ: 56, DZ: 69 | Right superior prefrontal | 45 % | 53 % | 50 % | ||
Right inferior prefrontal | 45 % | 48 % | 55 % | ||||
Right medial frontal | 37 % | 39 % | 47 % | ||||
Right superior frontal | 35 % | 47 % | 78 % | ||||
Right subcallosal | 44 % | 40 % | 42 % | ||||
Right cingulate | 37 % | 55 % | 68 % | ||||
Right cuneus | 48 % | 48 % | 51 % | ||||
Right parieto-occipital | 45 % | 42 % | 56 % | ||||
Left inferior prefrontal | 38 % | 45 % | 49 % | ||||
Left superior temporal | 44 % | 44 % | 48 % | ||||
Left inferior parietal | 50 % | 51 % | 51 % | ||||
Left lateral occipital | 34 % | 44 % | 46 % | ||||
Left parieto-occipital | 60 % | 54 % | 58 % | ||||
Note: list of brain areas where genetic innovation at age 12 was found | |||||||
Soelen van, et al. 2013 | CHILDREN Longitudinal, 3 years interval | TIME 1: |
Volume (Region of Interest)
| AE model | AE model | AE model | |
TIME 1
|
TIME 2
|
CHANGE
| |||||
MZ: 82, | Total brain | 93 % | 96 % | 19 % | |||
TIME 1: Mean age 9.2 (0.1) | DZ: 108 | Cerebrum | 93 % | 96 % | 20 % | ||
TIME 2: | TIME 2: | Cerebral GM | 88 % | 91 % | 3 % | ||
Mean age 12.0 (0.3) | MZ: 56, DZ: 69 | Cerebral WM | 89 % | 89 % | 18 % | ||
Cerebellum | 95 % | 95 % | 45 % |