Table 1.

The effect of transcranial alternating current stimulation on working memory.

References	Research object	Electrode position	Frequency (Hz)	Time (min)	Intensity (mA)	Electrode size	Cognition task	Effect of action
Jaušovec and Jaušovec (2014)	36 healthy adults with an average age of 20 ± 4.25 years old	Left parietal cortex (P3)+supraorbital frontal cortex (F3); Right parietal cortex (P4)+supraorbital region	ITF	15	1–2.25 (pp)	(5*5) cm2	N-back task memory task	Significantly improved working memory performance
Violante et al. (2017)	24 healthy adults, 27.38 ± 4.56 years old	Frontal/parietal region (F4/P4), T8 F4, and P4, T8	6	20	1 (pp)	(5*5) cm2	2-back/1-back and selective reactions	Improving speech working memory performance
Wolinski et al. (2018)	Group 1 has an average age of 28.3 ± 7.6, Group 2 has an average age of 22.8 ± 5.2, and each group has 16 people	Parietal cortex (P4)+vertex (Cz)	4, 7	12	1.24 ± 0.3 mA	(5*5) cm2	Working memory task	4 Hz increases the working memory capacity, while 7 Hz reduces the shared working memory capacity.
Zeng et al. (2022)	36 healthy adults with an average age of 23.67 ± 1.97	FP1-AP7, FP2-AF8	4, 8, sham	20	2 (pp)	(4.5*5.5) cm2	N-back task memory task	8 Hz can improve performance in verbal n-back tasks
Pahor and Jaušovec (2018)	72 healthy female students with an average age of 20.38 ± 1.48	Group 1:P3-P4, Group 2:F3-P3, Group 3:F4-P4, Group 4:F3-F4	Group 1: θ4.94, γ31.81; Group 2: θ4.89, γ33.22 Group 2: θ5.08, γ32.60 Group 4: θ5.28	15	2 (pp)	(7*5) cm2	N-back task memory task	θ-tACS stimulation in the posterior parietal lobe enhances working memory
Zhang et al. (2022)	20 healthy young participants with an average age of 22.45 ± 2.52	F4, P4	6	15	2(pp)	(5*5) cm2	N-back task memory task	6 Hz stimulation has no significant effect on low-load working memory

ITF represents an individual θ Frequency; Pp represents the peak-to-peak value of the current; Sham represents false stimulation.