新生儿情绪性语音加工的正性偏向——来自事件相关电位的证据

准确解码语音中的情绪信息能让个体更好地适应社会环境,此能力对新生儿和婴儿尤其重要,因为人类刚出生时听觉系统远比视觉系统发育得完善。虽然已有研究表明5～7月龄的婴儿能分辨不同情绪种类的语音,但目前对新生儿的研究还非常少。人类是否在出生时即具有分辨不同种类情绪性语音的能力?新生儿对情绪的加工是否存在正性或负性偏向?本文选用odd-ball范式考察高兴、恐惧、愤怒三种韵律性语音在1～6天龄新生儿大脑中诱发的事件相关电位。实验1直接对比三种情绪性条件,发现新生儿大脑的额区(F3和F4电极点)可以区分情绪性语音的正负性,正性(高兴)语音诱发的"失匹配反应"幅度明显大于负性(愤怒和恐惧)语音。实验2采用偏差和标准刺激反转的odd-ball范式,证实了实验1的结果并非源于三种情绪语音物理属性的差异。本文的结果提示,新生儿大脑可自动辨别正性与负性情绪语音,但尚不能将愤怒和恐惧两种负性语音区分开来。更重要的是,高兴语音比两种负性语音诱发了更大的失匹配反应,这一结果首次从神经学层面(电生理指标)为新生儿情绪性语音加工的正性偏向提供了证据。

Early preference for positive over negative prosody in neonates: Evidence based on event-related potentials

Our ability to process emotional prosody, that is the emotional tone of a speaker, is fundamental to human communication and adaptive behaviours. Very early in development, vocal emotional cues are more critical than facial expressions in guiding infants' behavior. However, the processing of emotional prosody in the very early days of life is still far from clearly understood. It is unclear whether the discrimination between prosodies with different emotional categories is present at birth. Furthermore, it is unknown whether there is a preferential orientation (negativity bias versus positivity preference) in neonates.