Redcay Elizabeth, Kleiner Mario, Saxe Rebecca
Department of Psychology, University of Maryland, College Park MD, USA.
Front Hum Neurosci. 2012 Jun 22;6:169. doi: 10.3389/fnhum.2012.00169. eCollection 2012.
When engaging in joint attention, one person directs another person's attention to an object (Initiating Joint Attention, IJA), and the second person's attention follows (Responding to Joint Attention, RJA). As such, joint attention must occur within the context of a social interaction. This ability is critical to language and social development; yet the neural bases for this pivotal skill remain understudied. This paucity of research is likely due to the challenge in acquiring functional MRI data during a naturalistic, contingent social interaction. To examine the neural bases of both IJA and RJA we implemented a dual-video set-up that allowed for a face-to-face interaction between subject and experimenter via video during fMRI data collection. In each trial, participants either followed the experimenter's gaze to a target (RJA) or cued the experimenter to look at the target (IJA). A control condition, solo attention (SA), was included in which the subject shifted gaze to a target while the experimenter closed her eyes. Block and event-related analyses were conducted and revealed common and distinct regions for IJA and RJA. Distinct regions included the ventromedial prefrontal cortex for RJA and intraparietal sulcus and middle frontal gyrus for IJA (as compared to SA). Conjunction analyses revealed overlap in the dorsal medial prefrontal cortex (dMPFC) and right posterior superior temporal sulcus (pSTS) for IJA and RJA (as compared to SA) for the event analyses. Functional connectivity analyses during a resting baseline suggest joint attention processes recruit distinct but interacting networks, including social-cognitive, voluntary attention orienting, and visual networks. This novel experimental set-up allowed for the identification of the neural bases of joint attention during a real-time interaction and findings suggest that whether one is the initiator or responder, the dMPFC and right pSTS, are selectively recruited during periods of joint attention.
在进行共同注意时，一个人引导另一个人的注意力指向一个物体（发起共同注意，IJA），然后第二个人的注意力随之转移（回应共同注意，RJA）。因此，共同注意必须发生在社会互动的背景下。这种能力对语言和社会发展至关重要；然而，这项关键技能的神经基础仍未得到充分研究。研究的匮乏可能是由于在自然的、偶然的社会互动过程中获取功能磁共振成像数据存在挑战。为了研究IJA和RJA的神经基础，我们采用了双视频设置，在功能磁共振成像数据采集期间，通过视频实现了受试者与实验者之间的面对面互动。在每次试验中，参与者要么跟随实验者的目光看向目标（RJA），要么提示实验者看向目标（IJA）。还设置了一个对照条件，即独自注意（SA），在此条件下，受试者看向目标时实验者闭上眼睛。进行了组块分析和事件相关分析，揭示了IJA和RJA的共同区域和不同区域。不同区域包括RJA的腹内侧前额叶皮层以及IJA的顶内沟和额中回（与SA相比）。联合分析显示，在事件分析中，IJA和RJA在背内侧前额叶皮层（dMPFC）和右后颞上沟（pSTS）存在重叠（与SA相比）。静息基线期间的功能连接分析表明，共同注意过程会激活不同但相互作用的网络，包括社会认知、自愿注意定向和视觉网络。这种新颖的实验设置能够识别实时互动过程中共同注意的神经基础，研究结果表明，无论一个人是发起者还是回应者，在共同注意期间dMPFC和右pSTS都会被选择性激活。
