Visuo-motor control in low birth weight children without major ophthalmic or neurologic sequelae

Abstract

Aim: To evaluate in a pilot study the use of a touchscreen test in very low birth weight (VLBW) children to explore aspects of visuo-motor behaviour, measuring spatial localisation. Results in VLBW subjects will be compared with those in children born at term. It will be investigated whether any deficits found were related to parental reports of visual function difficulties. Methods: A range of visual functions were measured and IQ estimated using subtests from a standardised test. Using a touch-screen monitor to record pointing positions, in task 1 subjects pointed to sequences of visual targets as soon as they appeared and in task 2 they pointed after a memory delay. Results: Thirty-seven VLBW subjects and 32 control subjects were recruited. On task 1 there was no difference in the pointing error magnitude between the groups. Although the errors of the VLBW group were more variable, this was not statistically significant after exclusion of VLBW subjects with IQ <70. However, on task 2 the VLBW group remembered fewer complete sequences, leading to significantly higher average pointing errors when data were averaged over all sequences. When pointing error was averaged over only correctly remembered sequences, there was again no difference between the groups. Conclusions: Our results indicate that pure spatial localisation in the absence of a memory load in VLBW children is comparable to the performance of children born at term. However, deficits are apparent in VLBW children when working memory is introduced, and this is consistent with the findings of other studies.

Keywords

• IQ
• Low birth weight
• Memory
• Spatial localisation
• Visual function