Repetitive transcranial magnetic stimulation (rTMS) generates
an electric current that induces cortical modulation and
brings about long‑lasting neuronal plasticity changes using a
noninvasive technique.[19] It has been reported to improve the
language ability, memory capacity, and executive functions for
several weeks after a short period of treatment.[20,21] The rTMS
combined with cognitive training seems to be a beneficial,
effective and promising modality for AD treatment.[22] A second
method, however, has drawn public attention in more recent
years. Transcranial direct current stimulation (tDCS) induces
neural modulation of cortical excitability and its favorable
effects outlast the period of stimulation. It has been proven
that tDCS is not only helpful in treating cognitive dysfunction
but also helps in reducing the P300 latency, which is
acknowledged to be abnormally increased in patients suffering
from AD.[23] The neuro‑modulation methods, including DBS,
rTMS, and tDCS have been applied in patients with AD with
certain curative benefits. However, the sample size being
studied is usually small, and the time points of stimulation,
the duration of treatment, and the safety of the procedure
are still unknown. Moreover, large‑scale clinical trials are
required to prove its efficacy before neuro‑modulation can
be incorporated as a conventional treatment for AD.