Ph.D., University of Pittsburgh
Although elementary cognitive processes are in place by early childhood, the capacity for abstract thought, planning, and cognitive flexibility continue to develop throughout adolescence. Similarly, although basic brain structure is adult-like by childhood, important brain maturation occurs during this age period including synaptic pruning and myelination. This is a particularly important age period, recognized as the time of onset of serious neuropsychiatric disorders including schizophrenia, and mood and substance abuse disorders. Unfortunately, very little is known about the processes underlying the transition into higher-order cognitive capabilities. Dr. Luna is interested in characterizing the changes that occur in brain function that subserve the maturation of cognition. She does this by bridging developmental psychology and neuroscience. Her current work focuses on delineating the systems-level pattern of brain activation subserving voluntary response suppression and spatial working memory. Her studies use eye movement paradigms that have been well-delineated at the single-cell level in the non-human primate. She uses both quantitative eye movement measures in the laboratory and performs neuroimaging studies using fMRI. One of Dr. Luna's aims is to establish a template of normal development from which to assess abnormal function in neuropsychiatric disorders. Hence, she is also involved in studies characterizing the functional neuroanatomy of high-functioning autistic individuals.
Her recent findings have revealed that performance in oculomotor tasks requiring voluntary response suppression and spatial working memory shows a significant developmental improvement throughout adolescence. Her fMRI studies have demonstrated that during these cognitive eye movement tasks activation in neocortical regions is present in childhood and increase in extent with age. Moreover, more distal regions known to subserve more precise regulation of behavior, like the cerebellum, are only active in the adult brain. These findings suggest that different stages of cognitive development may be subserved by distinct patterns of brain function and that proficient use of spatial working memory and voluntary response suppression require efficient circuit-level brain organization, possibly subserved by synaptic pruning and myelination that continues into late adolescence. Her recent studies on autistic individuals has revealed that while patients access the basic oculomotor system as healthy controls do to perform cognitive oculomotor tasks, they do not seem to rely on neocortical regions used by healthy individuals known to subserve higher-order cognition.
- Geier CF, Garver KE, Luna B: Circuitry underlying temporally extended spatial working memory. Neuroimage 35(2): 904-915, 2007.
- Luna B, Doll SK, Hegedus SJ, Minshew NJ, Sweeney JA: Maturation of executive function in autism. Biol Psychiatry 61(4): 474-471, 2007.
- Scherf KS, Behrmann M, Humphreys K, Luna B: Visual category-selectivity for faces, places, and objects emerges along different developmental trajectories. Developmental Sci 10(4): F15-30, 2007.
- Asato MR, Sweeney JA, Luna B: Cognitive processes in the development of TOL performance. Neuropsychologia 44(12): 2259-2269, 2006.
- Scherf KS, Sweeney JA, Luna B: Brain basis of developmental change in visuospatial working memory. J Cogn Neurosci 18(7): 1045-1058, 2006.
- Luna B, Garver KE, Urban TA, Lazar NA, Sweeney JA: Maturation of cognitive processes from late childhood to adulthood. Child Dev 75(5): 1357-1372, 2004.
- Luna B, Sweeney JA: The emergence of collaborative brain function: fMRI studies of the development of response inhibition. Ann N Y Acad Sci 1021: 296-309, 2004.