Mechanism of automatic processing of cartoon facial expressions:a mismatch negativity study / 中华行为医学与脑科学杂志

ABSTRACT

Objective To investigate the mechanism of automatic processing of cartoon facial expressions by using event-related potential(ERP).Methods Sixteen healthy volunteers (7 males and 9 females) were recruited for this study.The subjects were instructed to mentally count green faces (targets) and ignore the red ones (non-targets) including standard neutral expressions and deviant emotional expressions.Thirty two channels electroencephalogram (EEG) was recorded by Neuroscan Nuamps System.The amplitudes of mismatch negativity (MMN) were analyzed.Results (1) MMN1the amplitudes were(-0.570 ± 0.076) μV (TP7/TP8),(-0.840 ±0.119) μV(A1/A2) ,(-1.199 ±0.105)μV(T5/T6) ,(-1.184 ±0.102)μV(O1/O2).There was a significant main effect of site (F(3,45) = 8.340, P ＜ 0.05 ) and an interaction of orientation × hemisphere (F(1,15) =11.977, P＜0.05).( 2 ) MMN2 the amplitudes were (-0.469 ± 0.126 ) μV ( TP7/TP8 ), (-1.014 ± 0.255 ) μV(A1/A2) ,(-1.071 ±0.182)μV(T5/T6), (-0.915 ±0.178)μV (O1/O2).There was a significant main effect of orientation (F(1,15) = 7.232, P ＜ 0.05 ) and interactions of orientation × type (F(1,15) = 6.458, P ＜ 0.05 )and orientation × hemisphere(F(1,15) = 11.907, P＜0.05 ).Conclusion Cartoon emotional faces elicit expressionrelated MMN indexing automatic processing.The MMN amplitude is right-lateralized and larger for negative than positive expression.