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

摘要

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. Meth-ods Seventy-eight undergraduates were randomly divided into four groups by simple random sampling meth-od. 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 re-peated measurement variance analysis. Results (1) The interaction between short-term(3 min) stimula-tion of tDCS and facial expression was statistically significant (F(1,22)=7. 448,P=0. 012). There was signifi- cant 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 sig-nificant difference in the correlation between prolonged tDCS stimulation(15 min) and face expression recog-nition ( 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 ex-pression (F(1,17)=2. 566,P=0. 128) when visual stimulus was changed to non-expressive faces. Conclu-sions By applying tDCS technique,the present findings suggest that modulating DLPFC can influence emo-tional face perception,and support the valence-specific lateralization of emotional perception.