Maturing Thalamocortical Functional Connectivity Across Development

Department of Psychiatry, Oregon Health and Science University Portland, OR, USA.
Frontiers in Systems Neuroscience 05/2010; 4(10):10. DOI: 10.3389/fnsys.2010.00010
Source: PubMed

ABSTRACT Recent years have witnessed a surge of investigations examining functional brain organization using resting-state functional connectivity MRI (rs-fcMRI). To date, this method has been used to examine systems organization in typical and atypical developing populations. While the majority of these investigations have focused on cortical-cortical interactions, cortical-subcortical interactions also mature into adulthood. Innovative work by Zhang et al. (2008) in adults have identified methods that utilize rs-fcMRI and known thalamo-cortical topographic segregation to identify functional boundaries in the thalamus that are remarkably similar to known thalamic nuclear grouping. However, despite thalamic nuclei being well formed early in development, the developmental trajectory of functional thalamo-cortical relations remains unexplored. Thalamic maps generated by rs-fcMRI are based on functional relationships, and should modify with the dynamic thalamo-cortical changes that occur throughout maturation. To examine this possibility, we employed a strategy as previously described by Zhang et al. to a sample of healthy children, adolescents, and adults. We found strengthening functional connectivity of the cortex with dorsal/anterior subdivisions of the thalamus, with greater connectivity observed in adults versus children. Temporal lobe connectivity with ventral/midline/posterior subdivisions of the thalamus weakened with age. Changes in sensory and motor thalamo-cortical interactions were also identified but were limited. These findings are consistent with known anatomical and physiological cortical-subcortical changes over development. The methods and developmental context provided here will be important for understanding how cortical-subcortical interactions relate to models of typically developing behavior and developmental neuropsychiatric disorders.

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Available from: Damien A Fair, Aug 23, 2015
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    • "Although the nature of the thalamic disruption in autism is unclear, there seems to be a dysregulation of the normal reciprocal synaptic relationship between the thalamus in the cortex that occurs during development (Fair et al., 2010; Righi et al., 2014). If MD afferent quantity is strictly coordinating PFC synaptic density, hypothetically, thalamic abnormalities could disrupt the normal developmental reduction in synapse number resulting in an over-pruning or under-pruning and compromising PFC function (see Figure 2). "
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    • "delman 2000 ) , autism ( Just et al . 2007 ) , Alzheimer ' s disease ( Greicius et al . 2004 ) , Tourette syndrome ( Church et al . 2007 ) , and adult ADHD ( Castellanos et al . 2008 ) . With regard to development , cortico – cortical interactions measured with rs - fcMRI have been investigated from birth through adulthood ( Supekar et al . 2009 ; Fair et al . 2007 , 2008 , 2009 , 2010a ; Kelly et al . 2009 ; Fransson et al . 2007 ) . It is largely believed that the changes in connectivity throughout development may contribute to the shift from reflexive , stimulus - bound behavior in childhood , to the goal - directed and more flexible functioning that is found in adulthood ."
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