Sustained Attention Evokes Disordered Topology in Brain Connectomics in OCD
Poster No:
520
Submission Type:
Abstract Submission
Authors:
Mario Yacou1, John Kopchick2, Phillip Easter3, David Rosenberg3, Vaibhav Diwadkar3
Institutions:
1Wayne State University, Sterling Heights, MI, 2Wayne State University, Department of Psychiatry, Detroit, MI, 3Wayne State University, Detroit, MI
First Author:
Co-Author(s):
Introduction:
Obsessive-compulsive disorder (OCD) is characterized by excessive anxiety-inducing thoughts (obsessions) leading to repetitive anxiety-reducing behaviors (compulsions); these symptoms can impact cognitive domains like attention (Menzies et al., 2007). Indeed, our recent work in OCD shows how variations in sustained attention demand impact effective connectivity in the ascending thalamocortical relay (Yacou et al., 2022). However, these impacts have not been investigated using connectomic measures such as graph theory (Rubinov & Sporns, 2010). Our current investigation addresses this lacuna. Here we used graph theoretic analysis to characterize dysfunctional topology of brain network repertoires in OCD. Topology was studied by focusing on changes in the Betweenness Centrality (BC) of nodes under varying attention demand. BC was chosen because as a metric for approximating the number of the shortest functional paths that traverse through the node, it provides a lucid index of a node's integrative role in the network (Rubinov & Sporns, 2010).
Methods:
Thirty-eight OCD subjects (Age: 11.08 – 22.81 yrs.; Mean Age: 16.53 yrs.; 18 males) and 44 healthy controls (HC, Age: 11.16 – 23.53 yrs.; Mean Age: 16.30 yrs.; 21 males) provided informed consent or assent to participate in the fMRI study (Siemens Verio 3T) using a modified version of the Continuous Performance Task, Identical Pairs (CPT-IP) (Figure 1). Participants detected repeating instances of rapidly presented two-digit or three-digit numbers (50 ms, 250 ms SOA) blocked into extended trials (120 s duration). The extended blocks were specifically used to induce sustained attention over extended periods of activity. Numerical magnitude (2- or 3-digit) provided a simple manipulation of attention demand. fMRI data were processed using typical methods (SPM12). For each participant and condition, fMRI time series were extracted from the 246-nodes and following summarization of functional connectivity (zero lag bivariate correlations), BC of each node was estimated. Then, on each node, we conducted a two-factor ANOVA to investigate main effects of group (OCD ≠ HC), the main effect of attentional load (Low ≠ High), and, of specific interest in this study, any interactions between the two factors (group and attentional load).
Results:
The most salient results from the ANOVA revealed nine nodes with statistically significant interactions between group and attention demand (Figure 2). As seen, in six frontal-parietal lobes, the insula and the putamen, an increase in attention demand lead to an increase in the integrative importance in HC but a decrease in the same in OCD. In a single thalamic node, we observed an inverse pattern.
Conclusions:
To our knowledge, this is the first evidence of task-induced disruptions in the network topology of the OCD brain, and our work complements and extends upon existing applications of graph theory to the resting state (Li et al., 2022). It appears that the OCD brain does not flexibly increase the integrative role of key frontal, parietal and striatal regions in response to increases in attention demand. Conversely, an aberrant increase in the BC of thalamic nodes in OCD suggests a replication of the abnormalities of the ascending relay (from the thalamus to the cortex) previously discovered in the disorder. More generally, given that the brain is prepared to flexibly respond to imposed tasks (Park & Friston, 2013), a combination of graph theory and parametric tasks can reveal compelling expressions in psychiatric conditions (Meram et al., 2023).
Disorders of the Nervous System:
Psychiatric (eg. Depression, Anxiety, Schizophrenia) 1
Modeling and Analysis Methods:
fMRI Connectivity and Network Modeling 2
Other Methods
Neuroinformatics and Data Sharing:
Brain Atlases
Perception, Attention and Motor Behavior:
Attention: Visual
Keywords:
FUNCTIONAL MRI
Obessive Compulsive Disorder
Psychiatric
Other - Graph Theory, Betweenness Centrality, Sustained Attention
1|2Indicates the priority used for review
Provide references using author date format
Menzies, L., Achard, S., Chamberlain, S. R., Fineberg, N., Chen, C. H., del Campo, N., . . . Bullmore, E. (2007). Neurocognitive endophenotypes of obsessive-compulsive disorder. Brain, 130(Pt 12), 3223-3236. doi: 10.1093/brain/awm205
Meram, E. D., Baajour, S., Chowdury, A., Kopchick, J., Thomas, P., Rajan, U., . . . Diwadkar, V. A. (2023). The topology, stability, and instability of learning-induced brain network repertoires in schizophrenia. Network Neuroscience, 7(1), 184-212. doi: 10.1162/netn_a_00278
Park, H. J., & Friston, K. (2013). Structural and functional brain networks: from connections to cognition. Science, 342(6158), 1238411. doi: 10.1126/science.1238411
Rubinov, M., & Sporns, O. (2010). Complex network measures of brain connectivity: uses and interpretations. Neuroimage, 52(3), 1059-1069. doi: 10.1016/j.neuroimage.2009.10.003
Yacou, M. A., Chowdury, A., Easter, P., Hanna, G. L., Rosenberg, D. R., & Diwadkar, V. A. (2022). Sustained attention induces altered effective connectivity of the ascending thalamo-cortical relay in obsessive-compulsive disorder. Front Psychiatry, 13, 869106. doi: 10.3389/fpsyt.2022.869106