Efficacy and Olfactory Network of Electro-acupuncture for Subjective Cognitive Decline: A Multicenter Randomized Controlled Trial and fMRI Study

Firstly, EA treatment will be administered at the Neiguan (PC6, bilateral), Shenting(GV23), Yingxiang(LI20, bilateral), Yintang(GV29) acupoints. Disposable stainless-steel needles (0.25 mm × 25 mm; Huatuo brand, Suzhou Medical Supplies Factory Co., LTD., Suzhou City, China) will be used. After skin disinfection, the acupuncturists will twist and thrust the needle handles to achieve the sensations of achiness, heaviness, and numbness (known as de qi) at all above-mentioned acupoints. Following needle manipulations, EA instruments (SDZ-V, Hwato brand, Suzhou Medical Supplies Factory Co., Ltd., Suzhou City, China) will be used to attach the needle handles at PC6, GV23, LI20, GV29, with a dilatational wave of 5 Hz and a current intensity of 2 \~ 4 mA depending on the patient's tolerance. The needles will be removed after 30 min. Participants will receive 24 sessions over 8 weeks at a frequency of 3 times per week.

Firstly, EA treatment will be administered at the non-acupoints near above-mentioned real acupoints. Disposable stainless-steel needles (0.25 mm × 25 mm; Huatuo brand, Suzhou Medical Supplies Factory Co., LTD., Suzhou City, China) will be used. After skin disinfection, the acupuncturists will take the needle into the acupoints without the sensations of de qi. Following needle manipulations, EA instruments (SDZ-V, Hwato brand, Suzhou Medical Supplies Factory Co., Ltd., Suzhou City, China) will be used to attach the needle handles at non-acupoints without the current. The needles will be removed after 30 min. Participants will receive 24 sessions over 8 weeks at a frequency of 3 times per week.