Stefania Petri, Martina Riberto, Walter Setti, Claudio Campus, Helene Vitali, Sabrina Signorini, Francesca Tinelli, Massimiliano Serafino, Sandra Strazzer, Giuseppina Giammari, Elena Cocchi, Monica Gori
U-VIP Unit for Visually Impaired People, Italian Institute of Technology, Genoa, Italy.
Department of Informatics, Bioengineering, Robotics, Systems Engineering (DIBRIS), University of Genoa, Genoa, Italy.
Dev Sci. 2025 Sep;28(5):e70067. doi: 10.1111/desc.70067.
Reach-to-grasp behavior is a key developmental milestone in infants, involving coordinated actions such as arm transport, hand pre-shaping, and hand opening and closing. Vision guides the development of these skills, and delays in visual input can impact infants with early visual impairments. However, the effects of a congenital visual impairment on reach-to-grasp behavior in early life remain largely unexplored. To address this gap, we compared the reach-to-grasp abilities of sighted (S) and visually impaired (VI) infants and children, focusing on temporal (Movement and Pick-up times) and motor parameters (body midline crossing with one or two hands and hand preference). We hypothesized that VI children would face greater challenges in planning and executing a rapid and accurate reach-to-grasp movement, particularly during the pick-up phase. To investigate this, we asked sighted and VI infants and children to grasp black spheres of different sizes, placed centrally, on the right, or the left of a table in a dimly lit room. Three key findings emerged from our analysis. First, VI children required more time to pick up the spheres compared to their sighted peers. Second, VI children showed a reduced frequency of one-handed body midline crossing when reaching for lateral spheres, but showed an age-related increase, especially when using both hands. Third, VI children showed no hand preference, unlike S children who favored their right hand for crossing the body midline. These results highlight the role of visual experience in developing effective goal-directed movements and support creating early evidence-based rehabilitation procedures. A video abstract of this article can be viewed at https://youtu.be/bjwkMQmdFoE. SUMMARY: Understanding the impact of visual impairment on exploration abilities is crucial, especially in early developmental stages. Currently, there is a significant research gap concerning fine motor skills, particularly reaching and grasping, in visually impaired infants during development. We proposed a playful task to collect behavioral data on reaching and grasping skills in visually impaired children. Results shed light on the pivotal role of visual experience during the first years of life in shaping the maturation of reaching and grasping skills.
伸手抓握行为是婴儿发育中的一个关键里程碑,涉及手臂移动、手部预塑形以及手部开合等协调动作。视觉引导这些技能的发展,视觉输入延迟会影响有早期视力障碍的婴儿。然而,先天性视力障碍对早期生活中伸手抓握行为的影响在很大程度上仍未得到探索。为了填补这一空白,我们比较了视力正常(S)和视力受损(VI)的婴儿及儿童的伸手抓握能力,重点关注时间参数(移动时间和抓取时间)和运动参数(单手或双手越过身体中线以及手偏好)。我们假设视力受损儿童在计划和执行快速准确的伸手抓握动作时会面临更大挑战,尤其是在抓取阶段。为了对此进行研究,我们让视力正常和视力受损的婴儿及儿童在光线昏暗的房间里抓取放置在桌子中央、右侧或左侧的不同大小的黑色球体。我们的分析得出了三个关键发现。第一,与视力正常的同龄人相比,视力受损儿童抓取球体需要更多时间。第二,视力受损儿童在抓取侧向球体时单手越过身体中线的频率降低,但随着年龄增长有所增加,尤其是在使用双手时。第三,视力受损儿童没有手偏好,而视力正常的儿童在越过身体中线时更倾向于使用右手。这些结果凸显了视觉经验在发展有效的目标导向运动中的作用,并支持制定早期基于证据的康复程序。本文的视频摘要可在https://youtu.be/bjwkMQmdFoE观看。总结:了解视力障碍对探索能力的影响至关重要,尤其是在早期发育阶段。目前,关于视力受损婴儿在发育过程中的精细运动技能,特别是伸手和抓握方面,存在重大研究空白。我们提出了一项有趣的任务来收集视力受损儿童伸手和抓握技能的行为数据。结果揭示了生命最初几年视觉经验在塑造伸手和抓握技能成熟方面的关键作用。