Dynamic Systems Theory Model of Visual Perception Development
The dynamic system theory model of visual perception aims to facilitate practitioners in understanding the development of visual perception from a dynamic systems theory perspective. This model views vision and ocular motor abilities as a part (instead of the foundation) of the complex interaction of components of the experience of vision. Intelligent perceptual activity has other components including goal (intentional visual activity), attention and knowledge, retinal image, early visual processes, tactile and proprioception, postural and movement, language and culture, and motivation and emotions. Each component affects and affected by other components. The model aims to illustrate the complex, dynamic and multisensory nature of a visual activity. All components are interconnected, and each contributes to the goal through the dynamic process in the experience. Assessment and interventions using this model considers each child as unique, both genetic and experiential. This model adapts an ecological approach and fits with occupational-based model, as it centers on the goal or task and the child in his/her environment. It suggests that therapeutic activities should incorporate as many components with the visual experience as possible, e.g., language, movement and touch. Motivation for change and sense of self-efficacy associated with the patterns are essential to build on new successful patterns. Typical visual perception assessments can be used to assess performance, and occupational therapy assessment can be used to assess relevant factors that impact performance. The assessment goal is to determine how children are directing attention and employing their cognitive resources. Treatment can be then designed to include other modalities (verbal, pointing) to help children self-direct attention to relevant features that has been previously omitted.
Visual perceptual disorder
Domain of occupation
This model aims to clarify the complex and dynamic development of visual perception and to guide assessments and interventions.
Cote, C. A. (2015). A dynamic systems theory model of visual perception development. Journal of Occupational Therapy, Schools, & Early Intervention, 8(2), 157-169.
Sensory Integration Theory aims to explain behaviors, plan intervention, and predict behavioral change through intervention, and provide specific intervention strategies to remediate the underlying sensory issues that affect functional performance. It purposes therapeutic interventions that incorporate sensation to affect multi-sensory perception to influence learning and behavior, as the central nervous system does not process sensory information in isolation.
This frame of reference adapts a top-down approach to identify visual perceptual factors that limit an individual’s daily participation, and adaptive and compensation approaches are used to facilitate engagement in meaningful occupation. It uses theories from cognition, developmental psychology, education, and Warren’s developmental hierarchy of visual perceptual skills. Visual Perceptual skill development is viewed to be developed from a hierarchy, starting from oculomotor control, visual fields, visual acuity.
This frame of reference identifies functions and dysfunctions in five areas of handwriting for children, including proximal posture, components, use of writing tools, grasp, and handwriting. Good proximal control is required for functional and effective distal control of the writing tools. Either excessive postural stability or lack of postural stability during writing tasks is considered as dysfunctions. Components including ocular-motor skills, attention, and memory are considered as essential.
The psychoanalytic frame of reference (FOR) emphasizes on the unconscious aspect of what is done and said, and it is embedded in an occupational therapy relationship model of practice - the Vivaio model (MOVI). The central element of the MOVI is the recognition of constant emotions that exist in the interdependent relationship between the three elements of patient, therapist and ‘doing’.
This model aims to describe the symbiotic relationship between occupation and the brain, as a chaotic, self-organized, and complex system. It assumes that changes in human condition do not follow a linear path. The model views occupational therapy as a complex intervention and a result of dynamic integration of several factors and unpredictable outcomes. The concept of neuro-occupation is complex and holistic, and aims to help occupational therapists to apply the non-linearity principles.