**(A)** Exemplary connectivity strength and distance matrices of a single subject obtained by diffusion tensor imaging tractography and directionality matrix of the macaque obtained from the CoCoMac database. Shown are normalized capacities between different source nodes that resemble the weight of individual node interactions estimated by the size of the fiber tract connecting the nodes (*left*) and distances between nodes (*middle*) estimated by the fiber-tract length between source node voxels. In addition, directionality information (black: explicit no connectivity) obtained from macaque axon-tract tracing data of the CoCoMac database is shown (*right*). Area names of the 96 regions are listed in —ordering of regions is equal in table and matrices. **(B)** Empirical and simulated functional connectivity (FC) of functional magnetic resonance imaging (fMRI) data. By a coarse numerical parameter space search, we identified parameter settings that yielded functional blood oxygen level-dependent (BOLD) connectivity that significantly correlated with the FC of empirical fMRI data (in the shown example, a correlation of *r*=0.47 has been achieved). The window length of the empirical BOLD data used to calculate FC was 38 scans=73,72 sec (repetition time=1.94 sec/sampling rate 0.5155 Hz). Altogether, the empirical BOLD data collected for a single subject had the length of 666 scans. We slid the window for the calculation of the BOLD FC over the entire empirical time series in steps of a single volume resulting in 666−38=628 different empirical FCs per subject. Simulated BOLD data were obtained by convolving a simulated mean field time series of the excitatory population (duration: 200 sec; sampled at 250 Hz) with the hemodynamic response function. This signal was subsequently downsampling to the fMRI scan frequency, resulting in a timeseries of 86 samples. Simulated FC was calculated over an identical time window of 38 scans as in empirical data. By sliding the window over the simulated time series in one-scan steps, we obtained 86−38=48 different simulated FCs. All simulated FCs were compared to all empirical FCs by calculating correlation coefficients resulting in 628×48=30,144 *r* values per subject and parameter setting. In this initial coarse parameter space search, we tested 78 different parameter settings by varying the parameters GC, structural connectivity (SC), v_cond, K11, K21, K12, and the six noise terms (abbreviations explained in ). See examples for the distributions of resulting *r*-values in (C). The parameter values yielding the here-shown example of simulated data are listed in . The area names of the 96 regions for which FC is shown can be found in in the identical order as depicted here. **(C)** Individual structure predicts function. BOLD FC matrices of nine subjects (represented by the different panels) were correlated with simulated FC matrices based on SC of a single subject. Shown are the distributions of correlation coefficients (CCs) for 30,144 comparisons (628 empirical FCs×48 simulated FCs). The red-boxed panel contains the data where SC and FC come from same subject—resulting in notably higher CCs.

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