Does retinal microvasculature reflect neurocognitive development?

Neurocognitive development happens rapidly in childhood and occurs through a connection between the circulatory system and cerebral structure. Retinal microvasculature mirrors the cerebrovascular circulation system. An investigation in JAMA Network Open examines whether certain characteristics such as retinal venular widening and a higher vessel tortuosity illustrate neurocognitive development.¹

Researchers looked at mother-child pairs who were recruited at birth from February 2010 to June 2014 and also gave further consent at a follow-up visit from December 2014 to July 2018. They were followed up longitudinally in the prospective Environmental Influence on Aging in Early Life birth cohort. The Cambridge Neuropsychological Test Automated Battery, including tasks such as motor screening and spatial span, was used to test visuospatial working memory, short-term visual recognition memory, and attention and psychomotor speed.

A total of 251 were included in the study. Among the cohort, every 1 standard deviation widening in the central retinal venular equivalent led to the child performing relatively 2.74% more slowly on the motor screening test. The child would have 1.75% fewer correct delayed matching to sample assessment in total as well as made 2.94% more errors given a pervious correct answer in the delayed matching to sample task. When looking at the central retinal arteriolar equivalent, each 1 standard deviation widening led to an increase in total percentage of errors and errors given previous correct answers in the delayed matching to sample increased by 1.44% and 2.30%, respectively. No association with retinal vessel characteristics were seen with big/little circle and spatial span outcomes.

When discussing the study’s strengths, the investigators said that the analyses of the retinal images were done by one person who had been blinded to all of the study’s conditions. Additionally, there is not much normative data for the tasks used in the study for children aged 4 years, and study provides data for this area. One of the limitations is that performing the assessment on children aged 4 years can be difficult. Some children are unable to give a response during the first assessment. The investigators found that a test round that allowed children to attempt all of the assessments before being recorded greatly reduced the errors.

The investigators concluded that a child’s microvascular phenotype appeared to be linked to short memory. This link could mean that alterations to retinal microvasculature could provide a way to examine neurological development.

Reference

1. Luyten LJ, Dockx Y, Madhloum N, et al. Association of retinal microvascular characteristics with short-term memory performance in children aged 4 to 5 years. JAMA Netw Open. 2020:3(7):e2011537. doi:10.1001/jamanetworkopen.2020.11537