Department of Psychology, University of York, York, United Kingdom.
School of Psychology & Neuroscience, University of St Andrews, St Andrews, United Kingdom.
PLoS One. 2021 Jul 23;16(7):e0255241. doi: 10.1371/journal.pone.0255241. eCollection 2021.
Joint attention, or sharing attention with another individual about an object or event, is a critical behaviour that emerges in pre-linguistic infants and predicts later language abilities. Given its importance, it is perhaps surprising that there is no consensus on how to measure joint attention in prelinguistic infants. A rigorous definition proposed by Siposova & Carpenter (2019) requires the infant and partner to gaze alternate between an object and each other (coordination of attention) and exchange communicative signals (explicit acknowledgement of jointly sharing attention). However, Hobson and Hobson (2007) proposed that the quality of gaze between individuals is, in itself, a sufficient communicative signal that demonstrates sharing of attention. They proposed that observers can reliably distinguish "sharing", "checking", and "orienting" looks, but the empirical basis for this claim is limited as their study focussed on two raters examining looks from 11-year-old children. Here, we analysed categorisations made by 32 naïve raters of 60 infant looks to their mothers, to examine whether they could be reliably distinguished according to Hobson and Hobson's definitions. Raters had overall low agreement and only in 3 out of 26 cases did a significant majority of the raters agree with the judgement of the mother who had received the look. For the looks that raters did agree on at above chance levels, look duration and the overall communication rate of the mother were identified as cues that raters may have relied upon. In our experiment, naïve third party observers could not reliably determine the type of look infants gave to their mothers, which indicates that subjective judgements of types of look should not be used to identify mutual awareness of sharing attention in infants. Instead, we advocate the use of objective behaviour measurement to infer that interactants know they are 'jointly' attending to an object or event, and believe this will be a crucial step in understanding the ontogenetic and evolutionary origins of joint attention.
共同注意力，或与另一个个体共同关注某个物体或事件，是一种在婴儿前语言期出现的关键行为，并且可以预测其之后的语言能力。鉴于其重要性，令人惊讶的是，目前对于如何测量婴儿前语言期的共同注意力还没有共识。Siposova 和 Carpenter（2019 年）提出了一个严格的定义，要求婴儿和伙伴轮流将目光从物体转移到彼此身上（注意力协调），并交换交流信号（明确承认共同关注）。然而，Hobson 和 Hobson（2007 年）提出，个体之间的注视质量本身就是一种足够的交流信号，表明了注意力的共享。他们提出，观察者可以可靠地区分“共享”、“检查”和“定向”的注视，但这一说法的实证依据有限，因为他们的研究仅关注两名观察者对 11 岁儿童注视的检查。在这里，我们分析了 32 名未经训练的观察者对 60 个婴儿注视其母亲的分类，以检验他们是否可以根据 Hobson 和 Hobson 的定义可靠地区分。观察者的总体一致性较低，只有在 26 个案例中的 3 个案例中，大多数观察者的判断与接收注视的母亲一致。对于观察者在高于偶然水平上达成一致的注视，注视持续时间和母亲的整体交流率被确定为观察者可能依赖的线索。在我们的实验中，未经训练的第三方观察者无法可靠地确定婴儿向母亲发出的注视类型，这表明不应该使用主观判断来确定婴儿对共同注意力的感知。相反，我们主张使用客观行为测量来推断互动者知道他们“共同”关注某个物体或事件，并且相信这将是理解共同注意力的发生和进化起源的关键步骤。
