https://scholar.dgist.ac.kr/handle/20.500.11750/755 2026-11-11T11:05:17Z https://scholar.dgist.ac.kr/handle/20.500.11750/61169 Title: Graded prefrontal–sensory connectivity underlies cross-modal hierarchical control Author(s): Yoo, Taehyun; Jeon, Hyeon-Ae Abstract: Does the rostro–caudal architecture of the prefrontal cortex (PFC) generalize to support hierarchical control across sensory modalities? To address this question, we used functional magnetic resonance imaging while participants performed three cue-based tasks integrating auditory and visual modalities, requiring policy abstraction from auditory cues to motor responses, visual features, or visual dimensions. Behaviorally, increasing abstraction and complexity produced robust costs in accuracy and reaction time, underscoring the computational demands of cross-modal control. Univariate analyses revealed complexity-modulated effects within each level of abstraction and a corresponding anterior shift in PFC activation paralleling the hierarchical gradient. Multivoxel pattern analysis further demonstrated a representational shift, where caudal PFC encoded concrete motor responses, whereas rostral PFC represented abstract dimensions. Functional connectivity analyses revealed a complementary dissociation: caudal subregions showed selective, complexity-modulated coupling with primary sensory cortices during lower-level control, whereas rostral PFC exhibited functional independence from direct sensory coupling at the highest level of abstraction. Instead, increasing abstraction was associated with enhanced coupling among higher-order association areas, particularly between the superior temporal and intraparietal regions. Together, these findings extend prior unimodal research by demonstrating that hierarchical control is instantiated along a rostro–caudal gradient that flexibly reconfigures prefrontal–sensory interactions to meet multiple sensory demands. This cross-modal hierarchical architecture enables a transition from direct sensorimotor mappings to abstract regulation, providing a neural basis for adaptive cognition in the complex, multisensory environments of everyday life. © 2026 The Author(s). 2026-06-30T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/47286 Title: What does Being an Expert Mean to the Brain Functional Specificity and Connectivity in Expertise Author(s): 전현애 Abstract: To what extent is varying cognitive expertise reflected in the brain’s functional specificity and connectivity? We addressed this question by examining expertise in mathematics based on the fact that mathematical skills are one of the most critical cognitive abilities known to be a good predictor of academic achievement. We investigated processing of hierarchical structures, which is a fundamental process for building complex cognitive architecture. Experts and nonexperts in mathematics participated in processing hierarchical structures using algebraic expressions. Results showed that a modulating effect depending on expertise was observed specifically in nonexperts in the left inferior frontal gyrus around pars triangularis and frontal sulcus, the left intraparietal sulcus, and the right inferior parietal lobule. This expertise-dependent pattern of activation led to a crucial dissociation within the left prefrontal cortex. More interestingly, task-related functional networks were also modulated differently in the frontoparietal network for relatively good performance and in the frontostriatal network for poor performance. The present study indicates that a high level of expertise is evident in a small number of specific brain regions, whereas a low level of expertise is reflected by broadly distributed brain areas, along with divergent functional connectivity between experts and nonexperts. 2017-01-18T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/47179 Title: Processing hierarchical structure in language and non-language domains Author(s): Jeon, Hyeon-Ae 2017-07-20T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/47172 Title: 언어와 비언어에서의 층위처리 Author(s): 전현애 2017-08-10T15:00:00Z