Effect of transcutaneous auricular vagus nerve stimulation on functional connectivity in the related brain regions of patients with depression based on the resting-state fMRI / 中国针灸

OBJECTIVE@#To explore the brain effect mechanism and the correlation between brain functional imaging and cognitive function in treatment of depressive disorder (DD) with transcutaneous auricular vagus nerve stimulation (taVNS) based on the resting-state functional magenetic reasonance imaging (rs-fMRI).@*METHODS@#Thirty-two DD patients were included in a depression group and 32 subjects of healthy condition were enrolled in a normal group. In the depression group, the taVNS was applied to bilateral Xin (CO15) and Shen (CO10), at disperse-dense wave, 4 Hz/20 Hz in frequency and current intensity ≤20 mA depending on patient's tolerance, 30 min each time, twice daily. The duration of treatment consisted of 8 weeks. The patients of two groups were undertaken rs-fMRI scanning. The scores of Hamilton depression scale (HAMD), Hamilton anxiety scale (HAMA) and Wisconsin card sorting test (WCST) were observed in the normal group at baseline and the depression group before and after treatment separately. The differential brain regions were observed before and after treatment in the two groups and the value of degree centrality (DC) of fMRI was obtained. Their correlation was analyzed in terms of HAMD, HAMA and WCST scores.@*RESULTS@#The scores of HAMD and HAMA in the depression group were all higher than those in the normal group (P<0.05). After treatment, the scores of HAMD and HAMA were lower than those before treatment in the depression group; the scores of total responses, response errors and perseverative errors of WCST were all lower than those before treatment (P<0.05). The brain regions with significant differences included the left inferior temporal gyrus, the left cerebellar peduncles region 1, the left insula, the right putamen, the bilateral supplementary motor area and the right middle frontal gyrus. After treatment, the value of DC in left supplementary motor area was negatively correlated to HAMD and HAMA scores respectively (r=-0.324, P=0.012; r=-0.310, P=0.015); the value of DC in left cerebellar peduncles region 1 was negatively correlated to the total responses of WCST (r=-0.322, P=0.013), and the left insula was positively correlated to the total responses of WCST (r=0.271, P=0.036).@*CONCLUSION@#The taVNS can modulate the intensity of the functional activities of some brain regions so as to relieve depressive symptoms and improve cognitive function.

Modulation of transcutaneous auricular vagus nerve stimulation on default mode network in patients with primary insomnia / 中国针灸

OBJECTIVE@#To explore the modulation of transcutaneous auricular vagus nerve stimulation (taVNS) on default mode network (DMN) in patients with primary insomnia (PI).@*METHODS@#A total of 22 PI patients (one patient dropped off and two patients were excluded) were included and treated with taVNS. The bilateral auricular points of Xin (CO15) and Shen (CO10) were selected and treated with disperse-dense wave at frequency of 4 Hz/20 Hz, the intensity was based on the patient's tolerance. taVNS was given once in the morning and once in the evening for 30 minutes each time. The treatment lasted for at least 5 days a week for 4 weeks. At the same time, 16 healthy subjects matched with gender and age were recruited. The Pittsburgh sleep quality index (PSQI) score was evaluated before and after treatment in PI patients. The resting-state functional magnetic resonance imaging (rs-fMRI) data of PI patients before and after treatment and healthy subjects at baseline period were collected to observe the effect of taVNS on the functional connection (FC) between posterior cingulate cortex (PCC) and whole brain.@*RESULTS@#After treatment, the total score of PSQI in PI patients was lower than that before treatment (P<0.01). Compared with healthy subjects, the FC of the left PCC was increased either with the left orbital superior frontal gyrus or with left middle frontal gyrus (P<0.001), and the FC between right PCC and left middle frontal gyrus was increased in PI patients before treatment (P<0.001). Compared before treatment, the FC between left PCC and left middle frontal gyrus was decreased (P<0.05), and the FC of the right PCC was decreased either with the right medial prefrontal cortex or with the left middle frontal gyrus in PI patients after treatment (P<0.001, P<0.01).@*CONCLUSION@#taVNS can modulate the FC between anterior and posterior DMN, and between DMN and cognitive control network of PI patients, which may be one of the brain effect mechanisms of taVNS in the treatment of PI patients.

Effect of acupoints with different tissue on electroacupuncture sensation / 中国针灸

<p><b>OBJECTIVE</b>To evaluate the influence on frequency, intensity and the amount of current flow produced by electroacupuncture sensation of acupoints with different distributions (meridian category, tissue type and nerve innervations).</p><p><b>METHODS</b>Twenty-one healthy volunteers were enrolled. According to the different tissue of acupoints, paired acupoints were grouped: Zusanli (ST 36) vs Yanglingquan (GB 34) (different meridian categories), Neiguan (PC 6) vs Daling (PC 7) (different tissue types), Zusanli (ST 36) vs Shuidao (ST 28) (different nerve innervations), Guanyuan (CV 4) vs Zhongwan (CV 12) (different nerve innervations), and Zusanli (ST 36) vs Guanyuan (CV 4) (different meridian categories, tissue types and nerve innervations). The electric frequency was 15 Hz. The electric current was under the participant's tolerance without sharp pain; the electroacupuncture was applied for three times with interval, 90 seconds totally. Soreness, numbness, fullness, heaviness, tingling, pressure, dull pain, warmness, coolness and amount of current flow were recorded, and the frequency, intensity and current amount between the paired acupoints were compared.</p><p><b>RESULTS</b>There were no significant differences in frequency of needling sensations between paired points (all P > 0.05). In the 9 electroacupuncture sensations, fullness, numbness and soreness were most commonly seen and obvious, heaviness, pressure and tingling came second, and dull pain, warmness, and coolness occurred at lower frequency. There were differences in the intensity of acupuncture sensation between paired acupoints in part of them, the soreness, fullness and heaviness at Zusanli (ST 36) were stronger than those at Shuidao (ST 28) (all P < 0.05 ); fullness and numbness at Zusanli (ST 36) were stronger than those at Guanyuan (CV 4) (both P < 0.01); fullness at Guanyuan (CV 4) was stronger than that at Zhongwan (CV 12) (P < 0.05 ); the current flow of electroacupuncture was similar between paired acupoints (all P > 0.05).</p><p><b>CONCLUSION</b>In the situation that there is no obvious difference in amount of current flow caused by electroacu puncture sensation, the obvious correlations between frequency of electroacupuncture sensation and tissue properties of acupoints are not appeared, and the difference of sensation intensity between paired acupoints may be associated with different nerve innervations. The frequency and intensity of electroacupuncture sensation at one acupoint are stable at different times.</p>