Visuospatial imagery is a fruitful strategy for the digit span backward task: a study with near-infrared optical tomography.
Our newly developed 64-channel time-resolved optical tomographic imaging system using near-infrared light enables us to obtain a quantitative image of hemoglobin concentration changes associated with neuronal activation in the human brain ¿H. Eda, I. Oda, Y. Ito, Y. Wada, Y. Oikawa, Y. Tsunazawa, M. Takada, Y. Tsuchiya, Y. Yamashita, M. Oda, A. Sassaroll, Y. Yamada, M. Tamura, Multi-channel time-resolved optical tomographic imaging system, Rev. Sci. Instrum., 70 (1999) 3595-3602. Here, we used this optical imaging system to demonstrate that the backward digit span (DB) task activated the dorsolateral prefrontal cortex (DLPFC) of each hemisphere more than the forward digit span (DF) task in healthy adult volunteers, and higher performance of the DB task was closely related to the activation of the right DLPFC. These results suggest that visuospatial imagery is a useful strategy for the DB task. Optical tomography described here is a new modality of neuropsychological studies.
Hoshi
Y
Y
Biophysics Group, Research Institute for Electronic Science, Hokkaido University, North Ward, North 12, West 6, Sapporo, Japan. yhoshi@imd.es.hokudai.ac.jp
Oda
I
I
Wada
Y
Y
Ito
Y
Y
Yutaka Yamashita
Oda
M
M
Ohta
K
K
Yamada
Y
Y
Mamoru Tamura
D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D010775:Photic Stimulation; D017397:Prefrontal Cortex / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*; D019265:Spectroscopy, Near-Infrared; D014793:Visual Cortex / Q000502:physiology