经颅直流电刺激右背外侧前额叶皮层对大学生情绪面孔识别的影响

Effect of transcranial direct current stimulation on emotional face perception over brain right dorsolateral prefrontal cortex in college students

目的探讨经颅直流电刺激((transcranial direct current stimulation,tDCS)大脑背外侧前额叶皮层(dorsolateral prefrontal cortex,DLPFC)对大学生情绪面孔识别的影响。方法采用简单随机抽样方法选取78名大学生,随机分为4组,每组均使用无创tDCS(强度1.5 mA)干预及情绪面孔识别试验。试验1组(n=23)给予3min tDCS干预脑DLPFC区、试验2组(n=17)给予15 min tDCS干预脑DLPFC区、试验3组(n=20)给予3min tDCS干预初级视皮质区、试验4组(n=18)进行非情绪图片测试;观察受试者对不同情绪面孔识别效果,结果行重复测量方差分析。结果(1)3 min tDCS短时刺激DLPFC区与面部表情识别相互作用显著(F(1,22)=7.448,P=0.012)。阳极tDCS刺激右侧DLPFC对积极面孔感知差异有统计学意义(刺激前:70.58%,期间:74.75%,P=0.036);但对消极面孔感知不明显(刺激前:70.58%,期间:70.73%,P=0.569)。(2)15min tDCS延长刺激与面孔表情识别相互关系不明显(F(1,16)=1.621,P=0.221)。(3)tDCS干预初级视皮层区,结果不受情感变量影响(F(1,19)<1,P>0.05)。(4)当视觉图像改为非表情面孔,tDCS作用与面部表情之间交互作用差异无统计学意义(F(1,17)=2.566,P=0.128)。结论tDCS调控DLPFC可以影响大学生情绪面孔识别,并支持"效价特定偏侧化(valence-specific lateralization)"情感感知理论。

Objective To investigate whether modulating the activation of dorsolateral prefrontal cortex(DLPFC)by transcranial direct current stimulation(tDCS)can influence emotional perception.Methods Seventy-eight undergraduates were randomly divided into four groups by simple random sampling method.TDCS(1.5 mA)noninvasive technique was used to test group 1(n=23)for 3 minutes to intervene in DLPFC,group 2(n=17)for 15 minutes to intervene in DLPFC,group 3(n=20)for 3 minutes to intervene in primary visual cortex,and group 4(n=18)for non-emotional picture test.The data were analyzed with repeated measurement variance analysis.Results(1)The interaction between short-term(3 min)stimulation of tDCS and facial expression was statistically significant(F(1,22)=7.448,P=0.012).There was significant difference in positive face perception(before:70.58%,period:74.75%,P=0.036)and no significant difference in negative face perception(before:70.58%,period:70.73%,P=0.569).(2)There was no significant difference in the correlation between prolonged tDCS stimulation(15 min)and face expression recognition(F(1,16)=1.621,P=0.221).(3)The primary visual cortex was not affected by anodal tDCS(F(1,19)<1,P>0.05).(4)There was no significant difference in the interaction between tDCS and facial expression(F(1,17)=2.566,P=0.128)when visual stimulus was changed to non-expressive faces.Conclusions By applying tDCS technique,the present findings suggest that modulating DLPFC can influence emotional face perception,and support the valence-specific lateralization of emotional perception.