Department of Psychology, University of South Carolina, Columbia, SC, USA.
Department of Psychology, University of South Carolina, Columbia, SC, USA.
Neuroimage. 2017 Mar 1;148:42-54. doi: 10.1016/j.neuroimage.2017.01.002. Epub 2017 Jan 2.
This study tested for neural representations of valence that are shared across visual and auditory modalities referred to as modality-general representations. On a given trial participants made either affective or semantic judgments of short silent videos or music samples. For each modality valence was manipulated at three levels, positive, neutral, and negative, while controlling for the level of arousal. Whole-brain crossmodal identification of affect indicated the presence of modality-general valence representations that distinguished 1) positive from negative trials (signed valence) and 2) valenced from non-valenced trials (unsigned valence). These results generalized across the two tasks. Brain regions that were sensitive to valence states in the same way for both modalities were identified by searchlight analysis of fMRI data by comparing the correlation of voxel responses to the same and different valence conditions across the two modalities. These analyses identified seven clusters that distinguished signed valence, unsigned valence or both. Signed valence was represented in the precuneus, unsigned valence in the bilateral medial prefrontal cortex, superior temporal sulcus (STS)/postcentral, and middle frontal gyrus (MFG) and both types were represented in the STS/MFG and thalamus. These results support the idea that modality general valence is represented in a network of several locations throughout the brain.
本研究检验了在视觉和听觉模态中共享的、被称为模态通用的效价神经表示。在给定的试验中,参与者对短的无声视频或音乐样本进行情感或语义判断。对于每种模态,效价在三个水平上进行操纵,即积极、中性和消极,同时控制唤醒水平。跨模态的整体影响识别表明存在模态通用的效价表示,这些表示区分了 1)积极与消极试验(有符号效价)和 2)有意义与无意义试验(无符号效价)。这些结果在两个任务中都具有普遍性。通过对 fMRI 数据进行搜索光分析,比较两种模态中相同和不同效价条件下的体素响应相关性,从而确定了对两种模态的效价状态以相同方式敏感的脑区。这些分析确定了七个区分有符号效价、无符号效价或两者的簇。有符号效价在顶下小叶中表示,无符号效价在双侧内侧前额叶皮层、颞上沟(STS)/中央后回和额中回(MFG)中表示,两种类型都在 STS/MFG 和丘脑中有表示。这些结果支持了这样一种观点,即模态通用的效价是由大脑中几个位置的网络表示的。