Joffe T H, Dunbar R I
School of Life Sciences, University of Liverpool, UK.
Proc Biol Sci. 1997 Sep 22;264(1386):1303-7. doi: 10.1098/rspb.1997.0180.
Social group size has been shown to correlate with neocortex size in primates. Here we use comparative analyses to show that social group size is independently correlated with the size of non-V1 neocortical areas, but not with other more proximate components of the visual system or with brain systems associated with emotional cueing (e.g. the amygdala). We argue that visual brain components serve as a social information 'input device' for socio-visual stimuli such as facial expressions, bodily gestures and visual status markers, while the non-visual neocortex serves as a 'processing device' whereby these social cues are encoded, interpreted and associated with stored information. However, the second appears to have greater overall importance because the size of the V1 visual area appears to reach an asymptotic size beyond which visual acuity and pattern recognition may not improve significantly. This is especially true of the great ape clade (including humans), that is known to use more sophisticated social cognitive strategies.
研究表明，灵长类动物的社会群体规模与新皮层大小相关。在此，我们通过比较分析表明，社会群体规模与非初级视皮层区域的大小独立相关，但与视觉系统的其他更直接组成部分或与情感暗示相关的脑系统（如杏仁核）无关。我们认为，视觉脑区组件作为一种社会信息“输入设备”，用于处理诸如面部表情、身体姿势和视觉地位标记等社会视觉刺激，而非视觉新皮层则作为一种“处理设备”，对这些社会线索进行编码、解释并与存储信息相关联。然而，后者似乎在整体上更为重要，因为初级视皮层区域的大小似乎达到了一个渐近值，超过这个值后，视敏度和模式识别可能不会显著提高。对于已知使用更复杂社会认知策略的大型猿类分支（包括人类）来说尤其如此。
