A Dynamic Systems Theory Model of Visual Perception Development

The neural substrates of visual organization in children and adolescents: An fMRI study

Deficient visual organization ability not only indicates possible brain dysfunctions but further affects an individual's daily activities. This study aimed to use functional magnetic resonance imaging (fMRI) to investigate the neural network contributing to visual organization abilities in children and adolescents. A two-choice version of the Hooper Visual Organization Test (T-HVOT) was adapted as the fMRI task for the present study. The effects of age and gender on overall visual perceptual functions and related neural foundations were also analyzed. Seventy children and adolescents were administered with the Test of Visual Perceptual Skill-Third Edition and 41 completed the fMRI scans. The whole-brain fMRI mapping results showed the cortical activation of multiple brain areas relating to visual organization. The greatest cortical activities were seen in the middle occipital gyrus, middle temporal gyrus, middle frontal gyrus and inferior frontal gyrus, and two age groups showed significant differences in cortical activation patterns as well. Gender had no significant effects on visual perceptual functions nor related cortical activation patterns. The overall visual perception functions improve with age, and the different cortical activation patterns indicated that the two groups adopt different strategies while performing visual organization tasks. The sensitivity and spatial resolution of fMRI allowed us to make specific conclusions about cortical regions involved in visual organization function and to provide a reference for objectively judging rehabilitative outcomes.

Modification of the training environment to improve functional performance using blacklight conditions: a case study of a child with autism

Objective: This retrospective case study of an eight year old female with autism illuminates how alteration of the training environment using florescent objects under blacklight conditions, may have been the facilitating impetus that increased her interaction with objects over time. Methods: This study approach was chosen to best correspond with establishment of an individualized education plan for a child with limited functional skills. The complicated task of teaching toothbrushing was broken down into 34 action steps, grouped into six training clusters that were chained together, using a hierarchy of prompts that were faded on every step, until the child functioned on each step independently. Her progress was evaluated by four points of data. Findings: The child interacted with objects and became independent in toothbrushing. Conclusion: Backlighting brought previously ignored objects into the foreground, enabling a child with autism to develop or accentuate visual focus. Future research about the effect of blacklight paired with powerful instructional techniques is recommended.