The Card Placing Test: a new test for evaluating the function of the retrosplenial and posterior cingulate cortices.

Background/aim: We developed a test named the Card Placing Test (CPT), which is potentially useful for evaluating a function of the retrosplenial and posterior cingulate cortices (RSC/PCC). Part A of the test assesses the ability of a subject to retain information on spatial locations of cards placed on the floor around the subject. Part B examines the subject's ability to integrate information on the spatial locations of similarly arranged cards and information on changes in body direction. The aim of this study is to identify brain regions involved in the CPT performance.

Subjects And Methods: Twenty-five subjects were recruited from our memory clinic. We analyzed the correlation between the CPT scores and resting state regional cerebral blood flow (rCBF) determined by single-photon emission tomography.

Results: The scores for part A correlated with rCBF in the right inferior parietal lobule. The scores for part B were associated with rCBF in the RSC/PCC.

Conclusions: The right inferior parietal lobule seems to play a pivotal role in performing part A of the CPT, whereas the RSC/PCC appears to be involved in accomplishing part B of the CPT.