Exploring the links between brain function and parent-infant interaction: A longitudinal study

自闭症是一种神经发育状况，其特征是社交互动受损，沟通受损以及限制性和重复性行为和兴趣，在英国学校人口中的患病率约为1%。由于其高遗传性，与没有自闭症的婴儿兄弟姐妹相比，自闭症儿童的兄弟姐妹有50%的风险发展为障碍或自闭症特征。对患有自闭症的年长兄弟姐妹的婴儿进行的前瞻性纵向研究表明，在两到三岁之前很少观察到行为诊断，而大脑功能测量能够在生命的第一年内识别早期的细微差异。例如，已经表明，后来接受诊断的婴儿兄弟姐妹表现出对眼睛凝视和面部的事件相关电位（ERP）反应改变，以及对社会相关视觉和听觉刺激的大脑激活减少。到第二年，明显的行为迹象包括社交和沟通行为逐渐减少，例如减少共同注意力，分享微笑和发声。然而，早期脑功能变化是否与随后的社会行为中的不确定性有关尚不清楚，这可能对早期干预具有重要意义。发展的transmittance模型支持这样的想法，即婴儿的社会能力的早期微妙的中断可能会改变父母对婴儿的反应和随后的亲子社会互动中的相互性。早期的脑功能差异可能会因不同脑区和儿童社会环境之间相互作用的复杂性而加剧，从而产生一种逐渐偏离健康表型的社会认知发展模式。例如，非典型的早期社会沟通技能可能会影响父母的反应，这可能会无意中减少社会关注的婴儿与预先存在的遗传脆弱性，导致越来越非典型的发展路线。为了支持这一观点，研究已经确定了大脑对眼睛凝视的反应（ERPs）与7个月大时自闭症风险较低的高危婴儿的亲子互动质量（PCI）之间的明确关系。这两个指标之间的联系也被发现在一个类似的研究中，研究人员涉及8个月大的婴儿处于危险之中，区分后来诊断的婴儿和未诊断的婴儿，并为未来的调查产生有希望的结果。目前的项目旨在扩展这项研究，建议遵循纵向设计，以检查大脑功能的不同措施，以应对社会刺激是否与非结构化PCI的婴儿在高和低风险的自闭症随着发育时间的推移，以及这种关联是如何与自闭症的结果。特别是，PCI措施将集中在父母的指导性，敏感的反应，婴儿对父母的注意力，婴儿的影响和相互性变量。这些变量区分了高危人群和低危人群，后三个变量预测了那些后来被诊断为自闭症的人。此外，研究还发现了ERP对眼睛注视的反应与婴儿情感和高危婴儿的注意力之间的联系。综上所述，该项目将提供重要的见解可能导致自闭症的结果和PCI可以在这些儿童的发展轨迹中发挥的作用的风险因素，这可能形成的基础上确定新的目标，为弱势婴儿的支持性早期干预。它还将为更好地理解大脑功能的测量如何与婴儿及其父母之间的自然互动以及它们是否可以在评估幼儿期临床诊断风险方面发挥预测作用提供垫脚石。

Autism is a neurodevelopmental condition characterised by impaired social interaction, impaired communication and restrictive and repetitive behaviours and interests with prevalence around 1% in the UK school population. Due to its high heritability, siblings of children with autism have 50% risk of developing the disorder or autistic traits compared to infant siblings without autism. Prospective longitudinal studies of infants with an older sibling with autism have shown that a behavioural diagnosis is rarely observable before the age of two to three years, while brain function measures have been able to identify early subtle differences within the first year of life. For instance, it has been shown that infant siblings who later receive a diagnosis exhibit altered event-related potential (ERP) responses to eye gaze and faces as well as a decreased brain activation to socially relevant visual and auditory stimuli. By the second year, overt behavioural signs include a gradual decrease in social and communicative behaviours, such as reduced joint attention, shared smiles and vocalisations. However, whether early brain function changes are linked to subsequent atypicalities in social behaviours is not yet clear and may have important implications for early intervention. Transactional models of development support the idea that early subtle disruptions in infants' social competence may alter parental responses towards the infant and subsequent mutuality in parent-infant social interactions. Early brain function differences may be exacerbated by atypicalities in interactions within different brain regions and the child's social environment, thereby producing a pattern of socio-cognitive development that gradually deviates from a healthy phenotype. For instance, atypical early social communicative skills are likely to influence parental responses which may inadvertently decrease social attention in infants with pre-existing genetic vulnerability, leading to an increasingly atypical developmental route. In support of this idea, research has identified clear relationships between brain responses to eye gaze (ERPs) and quality of parent-child interaction (PCI) in at-risk infants relative to those at low risk of autism at 7 months of age. Links between these two measures have also been found in a similar study undertaken by the researcher involving 8-month old infants at-risk, distinguishing later diagnosed from non-diagnosed infants, and yielding promising results for future investigation. The current project seeks to extend on this research, proposing to follow a longitudinal design in order to examine whether different measures of brain function in response to social stimuli are related to unstructured PCI in infants at high and low risk of autism over developmental time, and how this association is linked to autism outcome. Particularly, the PCI measure will focus on parental directiveness, sensitive responsiveness, infant attentiveness to parent, infant affect and mutuality variables. These variables have distinguished at-risk from low-risk groups, with the latter three variables predicting those who were later diagnosed with autism. Additionally, research has found links between ERP responses to eye gaze and infant affect and attentiveness in infants at-risk. Taken together, this project will offer significant insights into the possible risk factors leading to autism outcome and the role that PCI could play in these children's developmental trajectories, which could form the basis for identifying new targets for supportive early interventions for vulnerable infants. It will also provide a stepping stone towards a better understanding of how measures of brain function relate to naturalistic interactions between infants and their parents and whether they could both play a predictive role in assessing the risk of clinical diagnosis in early childhood.