5. Identify how local network
structures are evolving across
the lifespan, and how
sensitive these are to
random / targeted lesions
Whole-brain network Research objective
Modelling brain networks
6. Identify how local network
structures are evolving across
the lifespan, and how
sensitive these are to
random / targeted lesions
Whole-brain network Research objective
Statistical network
analysis
Modelling brain networks
7. Graph changes across lifespan
ng percentages of nodes with the highest betweenness centrality.
uated the consequences of random-node and hub-node damage
ocal structure parameters (e.g. edges, GWESP, GWNSP, and hemi-
nodematch). The effect of simulated damage between percentages
ated nodes was quantified with 95% credibility intervals obtained
difference between the posterior distributions.
3. Results
3.1. Network matrices and model parameters
We generated group-based networks for each age category
are depicted in Fig. 3 as network graph representations (for
Age 20-34 Age 20-34 vs Age 35-50
lost connections
new connections
8. Probabilistic: describe the probability of
the network structure
Generative: try to explain how the network
structure might have been generated
Assumption: links formation depend on
the relative presence / absence of some
local network structures
Exponential random graphs
14. The Bergm package for
On CRAN: CRAN.R-project.org/package=Bergm
Website: acaimo.github.io/Bergm
Bayesian
Analysis
Exponential
Random
Graph
Models
Missing Data
Imputation
Parameter
InferenceBergm
Model
Selection
Model
Assessment
15. Results
Fig. 5. Network parameters across lifespan. Edges, GWESP, GWNSP, and hemispheric nodematch for age categories 20–34, 35–50, 51–70, and N70 years of age.
86 M.R.T. Sinke et al. / NeuroImage 135 (2016) 79–91
Density Multiple Closure
Multiple Connectivity Hemispheric Density
Age groups Age groups
Structural
networks remain
stable across the
lifespan
16. Results
organization (Bullmore and Sporns,
dematch values indicate a tendency
(Dennis et al., 2013; Gong et al., 2009; Hagmann et al., 201
Montembeault et al., 2012; Otte et al., 2015; Wu et al., 2012; Z
Density Multiple Closure
Multiple Connectivity Hemispheric Density
Age groups Age groups
Hub-node
damage has
stronger effects
in people above
70 years of age
17. BERGM: many applications!
Knowledge transfer in
organisations
Foreign direct investment
flow dynamics
Sustainable energy
district planning
More info:
acaimo.github.io