title: Medial prefrontal and anterior cingulate cortical thickness predicts shared individual differences in self-generated thought and temporal discounting.
abstract: When deprived of compelling perceptual input, the mind is often occupied with thoughts unrelated to the immediate environment. Previous behavioral research has shown that this self-generated task-unrelated thought (TUT), especially under non-demanding conditions, relates to cognitive capacities such as creativity, planning, and reduced temporal discounting. Despite the frequency and importance of this type of cognition, little is known about its structural brain basis. Using MRI-based cortical thickness measures in 37 participants, we were able to show that individuals with a higher tendency to engage in TUT under low-demanding conditions (but not under high-demanding conditions) show an increased thickness of medial prefrontal cortex (mPFC) and anterior/midcingulate cortex. Thickness of these regions also related to less temporal discounting (TD) of monetary rewards in an economic task, indicative of more patient decision-making. The findings of a shared structural substrate in mPFC and anterior/midcingulate cortex underlying both TUT and TD suggest an important role of these brain regions in supporting the self-generation of information that is unrelated to the immediate environment and which may be adaptive in nature.
authors.affiliation: Department of Social Neuroscience, Max Planck Institute for Human Cognitive Brain Sciences, Leipzig, Germany. Electronic address: bernhardt@cbs.mpg.de.
authors.forename: Boris C
authors.initials: BC
authors.lastname: Bernhardt
authors.affiliation: Department of Social Neuroscience, Max Planck Institute for Human Cognitive Brain Sciences, Leipzig, Germany; Department of Psychology, University of York, York, UK.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Smallwood
authors.affiliation: Department of Social Neuroscience, Max Planck Institute for Human Cognitive Brain Sciences, Leipzig, Germany.
authors.forename: Anita
authors.initials: A
authors.lastname: Tusche
authors.affiliation: Department of Social Neuroscience, Max Planck Institute for Human Cognitive Brain Sciences, Leipzig, Germany; Department of Psychology, University of York, York, UK.
authors.forename: Florence J M
authors.initials: FJ
authors.lastname: Ruby
authors.affiliation: Department of Social Neuroscience, Max Planck Institute for Human Cognitive Brain Sciences, Leipzig, Germany.
authors.forename: Haakon G
authors.initials: HG
authors.lastname: Engen
authors.affiliation: Department of Social Neuroscience, Max Planck Institute for Human Cognitive Brain Sciences, Leipzig, Germany.
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Steinbeis
authors.affiliation: Department of Social Neuroscience, Max Planck Institute for Human Cognitive Brain Sciences, Leipzig, Germany.
authors.forename: Tania
authors.initials: T
authors.lastname: Singer
mesh_terms: D000328:Adult; D001931:Brain Mapping; D003071:Cognition / Q000502:physiology; D005260:Female; D006179:Gyrus Cinguli / Q000033:anatomy & histology* / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007206:Individuality; D008279:Magnetic Resonance Imaging; D008297:Male; D017397:Prefrontal Cortex / Q000033:anatomy & histology* / Q000502:physiology; D013850:Thinking / Q000502:physiology*; D055815:Young Adult