Reading skills develops with age. The development can be influenced by anatomical, neurological and physiological factors as well as external factors such as the phonological complexity of individual languages, socio-economic and personal contribution, etc. According to Fletcher’s classification, 10-15% of children have problems with information processing speed and automatic orthographic recognition of words, so cold the Magnocellular deficiency hypothesis – based on both anatomically smaller magno cells and their slower visual information transfer. It was found, when coherent sensitivity is reduced, reading difficulty is also observed at the appropriate age. The centers of motion and reading analysis are located in different areas of the cerebral cortex, thats show a significant interaction between the two mechanisms in the dorsal stream. There are many studies confirming that dyslexic patients and in patients with reading difficulties, autism, schizophrenia and Williams syndrome the psychophysical threshold of coherent motion perception is reduced.
The aim of this study was to determine credible coherent motion perception thresholds for children in typical stages of development at varying reading skill levels. This study included 2,027 children-participants (aged 7 to 18 years). The experiment stimulus consisted of 100 moving black dots, displayed for 0.25 seconds on a 12° white rectangular background at a distance of 50 cm. Both signal and noise dots traveled at identical velocities of 2, 5, or 8 deg/s. The children’s motion detection thresholds decreased with age for all dot velocities. The participants’ motion perception thresholds were significantly higher at 8 deg/s (p<0.0001), with a mean value of 51.3%±0.7, while the mean values for 2 and 5 deg/s, respectively, were 31.7%±0.6 and 33.7%±0.6. The only significant difference in motion perception between strong and weak readers occurred at a velocity of 2 deg/s (p=0.045). The cognitive features of the children’s reading language do not affect coherent motion perception; it develops slowly and steadily. 16% of school-aged children who have been categorized as slow readers exhibit high motion perception thresholds. For weak readers, the perception of coherent motion at a slow speed is different from strong readers due to vulnerability of the dorsal perceptual pathway in the developmental process.