Development of somatosensation in preterm infants: a neonatal precursor of sensory processing disorders in childhood

在英国，每年约有6万名婴儿早产。近年来，由于更好的新生儿护理，他们的存活机会稳步增加，然而，他们的神经发育结果仍然没有太大改善。超过40%的早产儿在处理感官信息方面会有困难，这将对他们的生活质量产生负面影响，使学习、协调和交流变得困难。早产儿可能会对轻微的刺激有夸大的反应，或者对痛苦的事情根本没有反应，他们也可能在协调动作或在长凳上保持平衡方面存在问题。这是因为到达他们大脑的感觉信息没有得到正确的处理。然而，我们不知道导致这些问题的机制，如何识别谁会出现感觉问题，以及何时进行干预。早产儿出生在他们大脑发育的关键阶段，提前暴露在外部世界中。他们中的许多人可以在新生儿护理中度过他们生命的头几个月，在那里他们暴露在与通常在子宫中经历的不同的、更强烈的刺激中。他们早产，这种经历可能会影响他们大脑发育的方式，并干扰负责处理外部环境的大脑回路的成熟。这种对感觉功能的早期破坏可能会对儿童探索和体验环境的方式产生连锁影响，这反过来将导致这一群体遭受感觉和认知方面的挑战。如果我们能够认识到出生时感觉和知觉有问题，临床医生和护理人员就可以在大脑回路仍在形成时进行干预，并有可能使它们走上正确的轨道。这些家庭还将受益于了解他们的孩子是如何发育的，以及他们如何支持他们提高获得良好结果的机会，例如通过使感觉环境适应儿童的功能需求。从长远来看，这将有助于减少早产儿及其家人在情感、心理、身体和经济上的挑战。该项目的总体目标是了解新生儿大脑正常情况下如何处理感觉信息，早产是如何影响这一过程的，以及这些功能中的问题是否会导致较晚的感觉处理和相关的神经发育障碍。感官是以阶梯状的层次结构进行处理的，最底层的“阶梯”在子宫早期发育，而更高的阶梯则在正常出生前发育。破坏这些步骤中的任何一个都会导致对环境的异常感知，因为它们在出生前就开始发育，可能容易早产。我们将绘制大脑功能的发展图，使个人能够过滤不必要的信息，将来自不同感官的信息组合在一起，并积极探索环境。然后，我们将评估这些功能是否更有可能在早产儿中发生改变，这些早产儿在医院护理的头几周里。最后，我们将跟踪这些婴儿直到30个月大，届时我们将能够测试他们的发育和感觉行为，并看看出生时的大脑处理是否可以预测长期结果。总而言之，了解新生儿大脑中感觉处理的发展将使护理人员和家庭能够为有感觉和相关神经发育障碍风险的婴儿提供早期有针对性的和个性化的干预。最后，考虑到神经发育和认知障碍在教育支持和提供护理方面与高昂的社会成本相关，而社区可以提供给他们的资源有限，研究结果将有助于政策制定者就卫生服务的资金问题作出决定。

About 60,000 infants are born prematurely each year in the UK. Their chances of survival have steadily increased in recent times thanks to better neonatal care, however, there is still not much improvement on their neurodevelopmental outcome. More than 40% of preterm children at school age will have difficulties in handling sensory information which will have a negative impact on their quality of life and make learning, coordination and communication a struggle. Prematurely born children may have exaggerated reactions to a mild stimulus or not respond at all to something painful and they may also have problems in coordinating their movements or balance on a bench. This is because the sensory information that reaches their brain does not get handled correctly. However, we do not know the mechanisms that lead to these issues, how to identify who will develop sensory problems and when to intervene.Preterm neonates are born during a critical phase of their brain development and are exposed to the external world ahead of time. Many of them can spend their first months of life in neonatal care, where they are exposed to different and more intense stimuli than those normally experienced in the womb. Their premature birth and this experience may affect the way their brain develops and interfere with the maturation of brain circuits that are responsible for processing the external environment. This very early disruption to sensory functions could have a cascading effect on how a child explore and experience their environment, which in turn will lead to the sensory and cognitive challenges suffered by this population. If we could recognise that there is something wrong with sensation and perception at birth, clinician and carers could intervene when the brain circuits are still forming and potentially put them on the right track. The families would also benefit from understanding how their children are developing and how they can support them to improve chances of a good outcome, for example by adapting the sensory environment to the child's functional needs. This would help reduce the emotional, psychological, physical and economic challenges of prematurely born children and their families in the long term.The overall aim of this project is to understand how sensory information is normally processed by the neonatal brain, how this is affected by premature birth and whether issues in these functions lead to later sensory processing and associated neurodevelopmental disorders. Senses are processed in a ladder-like hierarchy, with the bottom 'rungs' developing early in the womb, while higher rungs develop just before normal birth. Disruption to any of these steps will result in an aberrant perception of the environment and because they develop just before birth, they may be vulnerable to prematurity. We will map the development of the brain functions that allow an individual to filter out unnecessary information and to put together information coming from different senses, and to actively explore the environment. We will then assess whether these functions are more likely to be altered in preterm babies that spent their first weeks of life in hospital care. Finally, we will follow these babies up to 30 months of age when we will be able to test their development and sensory behaviour and see whether brain processing at birth can predict long-term outcomes.In summary, understanding the development of sensory processing in the neonatal brain will allow carers and families to provide early targeted and individualised interventions to infants at risk of sensory and associated neurodevelopmental disorders. Finally, the results will help policy makers in making decisions regarding funding for health services, considering that neurodevelopmental and cognitive disabilities are associated with high societal costs in terms of educational support and provision of care while the resources that communities can provide to them are limited.