Exploratory study of the effect of brain tumors on the default mode network
Resting state functional magnetic resonance imaging (RS-fMRI) is a popular method of visualizing functional networks in the brain. One of these networks, the default mode network (DMN), has exhibited altered connectivity in a variety of pathological states, including brain tumors. However, very few studies have attempted to link the effect of tumor localization, type and size on DMN connectivity. We collected RS-fMRI data in 73 patients with various brain tumors and attempted to characterize the different effects these tumors had on DMN connectivity based on their location, type and size. This was done by comparing the tumor patients with healthy controls using independent component analysis (ICA) and seed based analysis. We also used a multi-seed approach described in the paper to account for anatomy distortion in the tumor patients. We found that tumors in the left hemisphere had the largest effect on DMN connectivity regardless of their size and type, while this effect was not observed for right hemispheric tumors. Tumors in the cerebellum also had statistically significant effects on DMN connectivity. These results suggest that DMN connectivity in the left side of the brain may be more fragile to insults by lesions.
KeywordsDefault mode network Glioma Functional connectivity Posterior cingulate cortex fMRI
The authors are grateful for the help given by Russell Butler in the writing of this paper.
K.W. is supported by a Canada Research Chair in Neurovascular Coupling and the Natural Sciences and Engineering Council of Canada (NSERC). S.G. is supported by a research grant from the Faculty of Medicine and Health Sciences of Université de Sherbrooke.
- 4.Maesawa S, Bagarinao E, Fujii M, Futamura M, Motomura K, Watanabe H, Mori D, Sobue G, Wakabayashi T (2015) Evaluation of resting state networks in patients with gliomas: connectivity changes in the unaffected side and its relation to cognitive function. PLoS ONE 10:e0118072. doi: 10.1371/journal.pone.0118072 CrossRefPubMedPubMedCentralGoogle Scholar
- 5.Harris RJ, Bookheimer SY, Cloughesy TF, Kim HJ, Pope WB, Lai A, Nghiemphu PL, Liau LM, Ellingson BM (2014) Altered functional connectivity of the default mode network in diffuse gliomas measured with pseudo-resting state fMRI. J Neurooncol 116:373–379. doi: 10.1007/s11060-013-1304-2 CrossRefPubMedGoogle Scholar
- 7.Dacosta-Aguayo R, Grana M, Iturria-Medina Y, Fernandez-Andujar M, Lopez-Cancio E, Caceres C, Bargallo N, Barrios M, Clemente I, Toran P, Fores R, Davalos A, Auer T, Mataro M (2015) Impairment of functional integration of the default mode network correlates with cognitive outcome at three months after stroke. Hum Brain Mapp 36:577–590. doi: 10.1002/hbm.22648 CrossRefPubMedGoogle Scholar
- 13.Smith SM, Jenkinson M, Woolrich MW, Beckmann CF, Behrens TE, Johansen-Berg H, Bannister PR, De Luca M, Drobnjak I, Flitney DE, Niazy RK, Saunders J, Vickers J, Zhang Y, De Stefano N, Brady JM, Matthews PM (2004) Advances in functional and structural MR image analysis and implementation as FSL. NeuroImage 23(Suppl 1):S208–S219. doi: 10.1016/j.neuroimage.2004.07.051 CrossRefPubMedGoogle Scholar
- 14.Dipasquale O, Griffanti L, Clerici M, Nemni R, Baselli G, Baglio F (2015) High-dimensional ICA analysis detects within-network functional connectivity damage of default-mode and sensory-motor networks in Alzheimer’s disease. Front Hum Neurosci 9:43. doi: 10.3389/fnhum.2015.00043 CrossRefPubMedPubMedCentralGoogle Scholar
- 16.Filippini N, MacIntosh BJ, Hough MG, Goodwin GM, Frisoni GB, Smith SM, Matthews PM, Beckmann CF, Mackay CE (2009) Distinct patterns of brain activity in young carriers of the APOE-epsilon4 allele. Proc Natl Acad Sci USA 106:7209–7214. doi: 10.1073/pnas.0811879106 CrossRefPubMedPubMedCentralGoogle Scholar