VISUAL AND OCULAR CONTROL ANOMALIES IN RELATION TO READING DIFFICULTY*

Abstract

S ummary . The visual behaviour under both static and dynamic viewing conditions was examined in a group of 13‐year‐old successful readers, compared with a group of the same age retarded in reading. Each group was video recorded reading aloud, without sound, a passage on the Neale Analysis that was well within their capacity to read. Criteria for selection and experimental controls are described. Each group was assessed for letter chart visual acuity, and examined on the full range of tests on a standard vision screener. The range of fusion that could be obtained before binocular vision broke down was assessed using polarised vectographs. Each pupil was asked whether vision tended to become double when reading. Dynamic visual behaviour, ocular control, and associated postural compensation and muscular stress while actually reading were investigated. The data obtained from these static and dynamic tests were then compared for the successful and retarded reading groups. It was found that the group retarded in reading indicated a significant relationship between anomalies of dynamic binocular viewing and their reading attainment. On the tests under static viewing only one significant difference—poor stereopsis—could be found between the two groups. Research supports the notion that problems of dynamic binocular vision and control while reading are important.