1. Eosu Kim, Jeonghun Ku, Young-Chul Jung, Hyeongrae Lee, SunI.Kim, Jae-Jin Kim, Kee Nam Koong, Dong-Ho Song, Restoration of mammilothalamic functional connectivity through thiamine replacement therapy in Wernicke's encephalopathy, Neuroscience,(in press)
2. Jung YC, Ku J, Namkoong K, Lee W, Kim SI, Kim JJ., Human orbitofrontal-striatum functional connectivity modulates behavioral persistence, Neuroreport, 21(7), 502-6, 2010.3.12
The degree at which individuals maintain behavioral strategies during uncertain conditions varies widely; however, the neural bases of these individual differences remain unclear. This study examines the functional connectivity of the orbitofrontal cortex during a decision-making task using functional magnetic resonance imaging. The strength of the functional connectivity observed between the medial orbitofrontal cortex and the nucleus accumbens was determined to be correlated with the number of persistent responses made during the decision-making task. It is proposed that top-down control of the orbitofrontal cortex over the ventral striatum is a critical component underlying individual differences in decision making during uncertain conditions.
1. Deog Young Kim, Jeonghun Ku, Won Hyuk Chang, Tae Hoon Park, Jong Youb Lim, Kiwan Han, In Young Kim, Sun I. Kim, Assessment of post-stroke extrapersonal neglect using a three-dimensional immersive virtual street crossing program. Acta Neurologica Scandinavica 121(3), 171-177,2010.3.1
OBJECTIVE: To investigate the potential of our newly developed three-dimensional immersive virtual reality (VR) program modeled on a real street crossing as an assessment tool for extrapersonal neglect in stroke patients. METHODS: Thirty-two patients with right-hemispheric stroke (neglect group, 16; non-neglect group, 16) were enrolled. The deviation angle, reaction time, left-to-right reaction time ratio, visual and auditory cue rates, and failure rate were evaluated during missions to keep a virtual avatar safe from a traffic accident in the VR program. The line bisection test and letter cancellation test were also evaluated. RESULTS: The deviation angle, left-to-right reaction time ratio, left visual and auditory cue rates and left failure rate in the VR program showed significant differences between the two groups (P < 0.05). Depending on the direction of approach of the virtual car, the left parameters were significantly higher than the right parameters in the neglect group (P < 0.05). In the neglect group, the line bisection test correlated significantly with the deviation angle (P < 0.05). None of the other virtual reality parameters significantly correlated with the paper and pencil tests. CONCLUSION: Post-stroke neglect in the extrapersonal space can be easily and safely detected and measured using our three-dimensional immersive virtual street crossing program.