Poster D135, Monday, March 27, 8:00 – 10:00 am, Pacific Concourse
Individual differences in grey matter structure predict frequency of certain types of stimulus-independent thoughts
Sneha Sheth1, Kieran Fox1, Michael Jarrett1, Manesh Girn1, Mara Puertolas Lopez2, Matthew dixon1, Alexander Rauscher1, Kalina Christoff1; 1University of British Columbia, 2National Institute on Deafness and Other Communication Disorders
Stimulus-independent thought has been most famously tied to activity in brain regions of the default mode network (DMN). However, almost nothing is known about how the brain’s anatomical structure might vary in individuals with differing overall patterns of thought. For instance, individuals show marked differences in the frequency with which their thoughts are goal-related and emotionally positive – but are these individual patterns of thinking reflected at the level of neuroanatomy? We sought to explore the relationships between these individual propensities and grey matter concentration (using high-resolution T1 anatomical MRI scans). Following a morphometric neuroimaging scan, we allowed subjects to rest and think freely, interrupting their thinking at random intervals with occasional thought probes. A total of 120 probes asked subjects (i) whether their thoughts arose spontaneously, or whether they were intentionally directing them; (ii) whether thoughts were related to their current concerns and goals in life, or not; and (iii) whether they were emotionally pleasant, unpleasant or neutral. Overall individual difference scores were calculated for each participant (e.g., proportion of positive thoughts), and correlated with whole-brain grey matter concentration. We found distinctive patterns of grey matter structure correlated with individual propensity toward spontaneously arising vs. intentionally directed thoughts; thoughts related vs. unrelated to current concerns and goals; and emotionally pleasant vs. unpleasant thoughts. Moreover, these differences were observed in many regions beyond the DMN. Our results suggest that distinctive individual tendencies in the content and valence of stimulus-independent thinking are linked to correspondingly distinctive neuroanatomy.
Topic Area: THINKING: Other