Todorov Alexander, Engell Andrew D
Department of Psychology, Princeton University, Princeton, NJ 08540, USA.
Soc Cogn Affect Neurosci. 2008 Dec;3(4):303-12. doi: 10.1093/scan/nsn033. Epub 2008 Oct 1.
The amygdala is involved in the evaluation of novel stimuli, including faces. We examined whether the amygdala is engaged during the evaluation of emotionally neutral faces along trait-specific dimensions such as trustworthiness and attractiveness or along a general valence dimension. Using behavioral data from evaluation of faces on 14 trait dimensions and fMRI data from an implicit evaluation paradigm, we show that the extent to which the amygdala responds to variations of faces on specific dimensions is a function of the valence content of these dimensions. Variations on dimensions with clear valence connotations (e.g. trustworthiness) engaged the amygdala more strongly than variations on dimensions with less clear valence connotations (e.g. dominance). In addition to the amygdala, several other regions--right superior occipital gyrus, right middle temporal/occipital gyrus and bilateral fusiform gyri--were involved in valence evaluation of faces. However, the relation between these regions and face valence was accounted for by the amygdala's response to faces. The findings suggest that the amygdala (i) automatically evaluates novel faces along a general valence dimension; and (ii) modulates a face responsive network of regions in occipital and temporal cortices.
杏仁核参与对包括面孔在内的新异刺激的评估。我们研究了杏仁核在沿着诸如可信度和吸引力等特质特定维度或沿着一般效价维度对面孔进行情感中性评估的过程中是否被激活。利用来自对面孔在14个特质维度上进行评估的行为数据以及来自一个内隐评估范式的功能磁共振成像（fMRI）数据，我们发现杏仁核对面孔在特定维度上变化的反应程度是这些维度效价内容的一个函数。具有清晰效价内涵的维度（如可信度）上的变化比效价内涵较不清晰的维度（如支配性）上的变化更强烈地激活杏仁核。除了杏仁核之外，其他几个区域——右侧枕上回、右侧颞中/枕回以及双侧梭状回——也参与了对面孔的效价评估。然而，这些区域与面孔效价之间的关系是由杏仁核对面孔的反应所解释的。这些发现表明：（i）杏仁核沿着一般效价维度自动评估新异面孔；以及（ii）调节枕叶和颞叶皮质中对面孔有反应的区域网络。
