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Q. What is the difference in meaning between these words: visual, perceptual, and motor?
A. The Random House dictionary defines these terms as:
* Visual: relating to sight
* Perceptual: awareness through the senses
* Motor: concerned with motion

Q. What is the best way to identify which visual-perceptual-motor components need intervention and how to provide it?
A. Since activities are our basic therapeutic tools, clinical observations of individuals during functional activities is a useful way to assess, select treatment, and individualize that treatment (Erhardt, 2003). Frequently, the visual component is addressed only in terms of acuity or perception, and the motor control of eye muscles is not considered, especially in children with minor neurological dysfunction. Furthermore, the eyes may be considered in isolation, instead of integrated with the entire body systems.

Q. What are the questions we need to ask when we question the visual component of a child's learning problem?
1. How well can this child see (acuity)?
2. Is the child processing visual information correctly (perception)?
3. Are the eye movements coordinated and accurate (motor)?

Q. What are the functional components of eye movements?
A. There are a number of Visual Reflexes, such as the Dolls Eye that may not be integrated, and are interfering with voluntary control (see further explanation on the FAQs about Vision page). Voluntary movements are classified in the EDVA (Erhardt, 1989) as:
* Localization or Visual Approach (the eyes reaching out to find a target)
* Fixation or Visual Grasp (the eyes maintaining contact on the target)
* Ocular Pursuit or Visual Manipulation (the eyes tracking, converging/diverging, interacting with the target
* Gaze Shift or Visual Release (the eyes letting go of gaze to shift to another target).

Q. What are some examples of problems caused in school when those voluntary movements are compromised, and what can we do to help?
* If Localization is slow and/or inaccurate, the child will have trouble finding a certain place on a certain page in a certain book. Flashlight search games first on the ceiling while supine (head stable) in bed at night in a darkened room, later while sitting facing a wall (near space) could be structured so that the child is required to touch the light beam that is suddenly switched on in different areas.
* If Fixation is not maintained long enough to differentiate letters and numbers, the child will struggle with reading. Developmentally, the growing infant maintains fixation first on a stationary target with internal movement (puppets, mechanical mobiles, glass snow scenes), so toys with that component can be used to increase duration of fixation.
* An example of Ocular Pursuit is visual monitoring of hand during drawing and writing movements. Flashlight tag will improve tracking, in supine or sitting, with the light beam moved slowly in the various directions, and the child eventually following by superimposing his own flashlight.
* Gaze Shifts must be smooth and rapid for reading (scanning multiple groups of letters in near space) and copying schoolwork from the chalkboard (shifting from far/near). Card games and board games that require many types of gaze shifts in a play context will reduce the cognitive stress factors (Erhardt & Duckman, 1997).

Q. How much do individual learning styles vs. the school's teaching methods contribute to the child's problems?
A. We know that adult learners need different teaching methods. Some of us are very visual. We like written handouts and overhead transparencies. Others have a stronger auditory channel, and would rather listen to a speaker and watch video with sound. Because auditory learners do not want to take a lot of notes, they like handouts for a different reason. Of course, there are others who need kinesthetic/tactile reinforcement, and do better by taking notes, and doing labs, where they can do, move, and touch. Do our children have learning disabilities or learning differences? Are we seeing atypical learning or clever compensations for sensory integration deficits? We must ask ourselves these questions because there is such a wide range of "normal".

Q. How do balance and postural control problems impact learning in the school environment?
* Most obviously, these children will have difficulty in physical education classes and sports, may avoid opportunities to participate, and thus experience less practice in improving skills.
* Because balance is not automatic, maintaining posture in the classroom may require their constant attention, leaving very little energy for cognitive processing.
* These children often have trouble with multitasking, or may hurry through a task, compromising their coordination.
* There may be a mismatch of visual input and proprioceptive or vestibular input, interfering with smooth, efficient processing .

Q. How can we use the framework of motor learning phases to understand the process of task acquisition?
A. According to Light (1991), the three stages in motor learning are cognitive, associative, and automatic. The following table describes each stage and suggested intervention techniques for each stage.

CognitiveNew task, must first understand it, then explore different strategies, inconsistent performance, retaining good strategies, discarding others, resulting in significant improvement.To motivate must be sure task is important, model task with verbal instruction, demo, and/or manual assistance, as needed, many trials with feedback, taper off feedback, then request child's feedback.
Associative Most effective method has been determined, subtle adjustments, improvement more gradual, more consistency.No modeling, demo, handling, discussion, encourage experimentation, vary feedback, and only after big errors.
AutomaticAfter lots of experience, task is easy even with distractions, can do secondary task simultaneously, can attend to entire environment, not just details.Can achieve task under variety of conditions, secondary tasks and distractions, generalize with functional skills.


Erhardt, R. P. (1989). The Erhardt Developmental Vision Assessment (EDVA). Maplewood, MN: Erhardt Developmental Products.

Erhardt, R. P. (2011). The Visual-Perceptual-Motor Activities Collection. Maplewood, MN: Erhardt Developmental Products.

Erhardt, R. P. & Duckman, R. H. (2005). Visual-perceptual-motor dysfunction: Effects on eye-hand coordination and skill development. In M. Gentile (Ed.), Functional visual behavior in children: An occupational therapy guide to evaluation and treatment options (2nd ed., pp. 171-229). Bethesda, MD: The American Occupational Therapy Association.

Light, K. (May, 1991). Applied concepts of motor control and learning. Presented at the Fourth Annual NDTA Conference, Atlanta, Georgia.

* Visual-Perceptual-Motor Activities Collection and Related Videos

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