|Budget Amount *help
¥2,700,000 (Direct Cost: ¥2,700,000)
Fiscal Year 2002: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2001: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 2000: ¥1,500,000 (Direct Cost: ¥1,500,000)
The present study attempted to analyze three kinds of memory phenomena, repetition blindness, negative priming, and directed forgetting, by employing school-age children, college students, patients with frontal lobe damage, and those with alcoholic Korsakoff's syndrome as subjects. Theoretical analysis revealed that inhibitory phenomena are classified into three levels according to behavioral response, subject's intention of inhibition, and activation of irrelevant information. Comparisons of the performance on the tasks that measured the three kinds of memory phenomena were expected to permit us to clarify the nature of different types of inhibitory processing. Experimental analysis identified the materials and procedures that induced the three types of inhibitory phenomena robustly in college students. From an examination of the relation between children's inhibitory index and their teachers' ratings of inattention, it was found that, in comparison with grade-matched controls, first- to fourth-graders who were rated as inattentive showed poorer performance on the tasks that required intentional inhibition and sustained attention; in contrast, inattentive fifth- and sixth-graders' selective attention was inferior, but their sustained attention was not significantly different from other children's. Flanker and modality-interference tasks were taken by patients with frontal lobe damage and Korsakoff amnesics. Frontal patients were found to be significantly impaired in negative priming, but not in interference. Korsakoff patients were extremely slow in making responses, yet their negative priming and interference were both significant. These empirical findings suggest that the experimental tasks developed by the present study would help in elucidating the developmental trajectory of inhibitory functions and in assessing several types of inhibitory dysfunctions.