However, Takeda et al. [9] had never conducted a study
focusing on very mild AD, that is, the early stage of AD. To
detect AD early, a powerful screening test for verymild AD is
needed. On the other hand, the previous studies by Takeda
et al. [9] did not discuss sensitivity of the TTCC for mild
cognitive impairment (MCI). MCI is classified into several
types, and amnestic MCI (aMCI) is thought to lead to AD.
To prevent AD and implement early intervention, screening
tests are required to selectively detect aMCI. Therefore, the
present study was designed to assess the efficacy of the TTCC
for earlydetectionofAD. Patientswitheither verymildADor
aMCI were enrolled in the study.The symptoms of very mild
ADand aMCI are oftensimilar; thus, we also discusswhether
very mild AD and aMCI can be detected using reversebackward
presentation of figures (an interference task of
TTCC)