The practice of behavioural optometry is expanding, yet some in the eyecare professions doubt the efficacy of this holistic treatment for vision impairment. mivision invited three fifth year students from the University of New South Wales School of Optometry and Vision Science to review the history of behavioural optometry and explore its success.
Behavioural optometry is an alternative philosophy of optometry that adopts more of a holistic approach in treating the patient. It considers the visual system in conjunction with non-ocular systems such as behaviour, posture and the environment.
The practice of behavioural optometry involves more than simple lens prescriptions – it involves methods such as visual hygiene, prism, vision therapy and optical aids in order to enhance or restore visual function and performance.
According to the Australasian College of Behavioural Optometrists (ACBO), the goals of behavioural optometry are:
the sources of referrals are becoming more diverse – from occupational therapists, paediatricians, general practitioners, and special education needs co-ordinators for vision investigation or vision therapy
1. To prevent vision problems and eye problems from developing;
2. To provide remediation or rehabilitation for vision or eye problems that have already developed (eg. eye turn, short-sightedness, visual sequelae of brain trauma etc);
3. To develop and enhance the visual skills needed to achieve more effective visual performance in the classroom, work place, when playing sport and following recreational pursuits.1
While behavioural optometrists purport that their methods are based on the feedback they receive in everyday practice, some ophthalmologists and paediatricians question the benefits of their therapy.
The controversy of behavioural optometry lies in the opposing viewpoints from proponents and opposing professionals of the underlying theory behind the practice of behavioural optometry. This article aims to explore the success of behavioural optometry as well as the origins and development of concepts
and methods practised.
Origins of Behavioural Optometry
The origins of behavioural optometry are believed to have arisen from areas in strabismus orthoptics and refractive analysis.2 Orthoptics has a long history with eye training exercises that dates back to the middle ages.3 The early beginnings of orthoptics emphasised the importance of obtaining functional binocularity in strabismus through intense visual training exercises.2
Developments in the theory and management of strabismus led to the formation of a number of instruments, and the focus of orthoptics expanded towards eliminating suppression, amblyopia treatment and diagnosis.4 However, the overall goal of orthoptic treatment remained the same: to promote comfortable, sustainable, binocular vision. Today, orthoptists remain specialists in the diagnosis, assessment and management of strabismus, binocular vision and amblyopia while behavioural optometry has extended the use of visual training techniques beyond the correction of strabismus.
In behavioural optometry, a number of techniques are taken from analytical optometry. While traditional optometry paradigms emphasised refractive error and ocular disease, case analysis systems emphasised the importance of considering accommodative and convergence systems in determining the lens prescription. Beginning in the early 20th century, the works of optometric pioneers such as Donders, Landolt, Percival and Sheard, Hofstetter and Morgan incorporated the analysis of accommodation-convergence relationships into optometric practice, providing guidelines for the prescription of lenses.2 This system of optometric case analysis remains a core component of both behavioural optometry as well
as general optometric practice.
Development of Behavioural Optometry
In the development of behavioural optometry it is necessary to examine the influence of A.M. Skeffington. Skeffington, the father of behavioural optometry, disputed classical schools of thought and advocated vision as a
sensory modality in attaining and deciphering meaningful information
from the environment.
Skeffington’s near point stress model, a key concept in behavioural optometry, suggested that myopia was a result of an adaptive process from the physiological stress associated with the demands of near work.5 The stress imposed on the visual system to meet these demands results in a discrepancy between the convergence and accommodative systems where convergence is localised closer than accommodation leading to myopia. Based on these concepts, Skeffington developed his own standardised set of clinical procedures consisting of 21 points of analysis which became incorporated in several schools of optometry.6
Skeffington’s analysis sequence aims to determine a lens prescription which enables relief of patient symptoms, improvement of visual processing and prevention of visual maladaptations.6 Skeffington established the foundation of behavioural optometry and initiated a shift of focus in optometry from simply correcting refractive errors to enhancing visual comfort and function. Today, Skeffington’s model of myopia st
ill remains a key component of behavioural optometry, and the use of prescribing a near addition for the prevention of myopia is commonly practised.
Skeffington’s greatest contribution to the development of behavioural optometry is the notion that vision is a holistic process where sensory information is processed. His model of vision has been most famously represented by his four circles of vision (Figure 1). Skeffington argued that vision is beyond what is perceived from the eyes. The visual system included sensory input from the vestibular, tactile and proprioceptive systems, which enabled the brain to orientate the position of the body within space.7
Essentially, the four circles of Skeffington: Anti-gravity, Centering, Identification and Speech/Audition can be succinctly described through the questions of “Where am I?”, “Where is the object?”, “What is the object?”, “What do I know about it?” and “What can I tell you about it?” which the visual system aims to answer.8 The culmination of these elements results in the emergence of vision and formed the basis of both his approach, and that of behavioural optometrists today, in treating visual anomalies. Skeffington’s holistic approach remains a key tenet of behavioural optometry, emphasising that vision involves several subprocesses, which develop in an integrated process where a deficit in one can lead to an anomaly in motor skills and learning.
While Skeffington significantly contributed to the development of behavioural optometry, many concepts of behavioural optometry also arose from areas outside optometry. Samuel Renshaw, an American experimental psychologist, introduced elements of psychology to optometrists. His work involved perceptual research and the use of the tachistoscope to train military pilots, which enabled reading and comprehension speed to increase, perceptual spans to enlarge as well as myopia to reduce.8 Renshaw’s findings reinforced Skeffington’s concept of vision as a learned process and the notion that it can be enhanced through training.
Concepts and procedures of behavioural optometry have also developed from kinesthesiology. D.B. Harmon, a kinesthesiologist, explored the influence of the environment on posture and visual development in children. Harmon’s research suggested that environmental factors such as glare, classroom arrangement, and furniture design could affect posture and in turn skew gravitational and kinesthesiology inputs leading to the development of compensatory binocular and refractive anomalies. By incorporating concepts outside of traditional optometry, the practice of behavioural optometry was able to expand to assist individuals in not only solving their visual problems but also enhancing visual skills, learning and general development of motor function and behaviour.
Today, behavioural optometry continues to develop and incorporates knowledge from other sciences. A recent area of interest in behavioural optometry is neurodevelopmental optometry, where facets of neuroscience are incorporated into vision, development and learning. While current vision therapy aims to create schemata in order to overcome specific visual and learning deficits, neurodevelopmental optometry suggests that vision therapy should aim to enable individuals to learn to create their own schemata to overcome existing deficits as well as future challenges.9
Success of Behavioural Optometry
The success of behavioural optometry can be seen through its treatment efficacy, spread of practice, perception within the optometry, ophthalmology and general community as well as articles in scientific literature.
Since the early 20th century, behavioural optometry practice has increased from one man; Skeffington, to being localised to North America, and today being recognised in more than 37 countries.10
In Australia, ACBO is the primary authority on behavioural optometry with members consisting of approximately 10 per cent of practising Australian optometrists.11 In comparison, there are 75 members in the British Association of Behavioural Optometry (BABO).12 Behavioural optometry is popular in the United States and has been practised since the 1920s under the Optometric Extension Program Foundation.10
Referrals to behavioural optometrists are not only increasing in number, but the sources of referrals are becoming more diverse – from occupational therapists, paediatricians, general practitioners, and special education needs co-ordinators for vision investigation or vision therapy.13 The success and popularity of behavioural optometry is proven through academia; it is taught in U.S. Optometry Schools, it is a component of the Australian undergraduate course, and is also offered as a postgraduate masters course. This increasing spread of practice reflects the success of behavioural optometry in addressing patient concerns.
We can also consider the way that those outside the optometric field perceive these techniques. An insight into ophthalmologist and orthoptist perspectives can be gained by reading Helveston’s article, which illustrates a disapproving view towards vision therapy for most of the disorders that optometrists claim to be able to treat.4 While in optometric practice there is an in increase in vision therapy, throughout ophthalmologist and orthoptist communities, the use of vision therapy has declined to a point where it is
Helveston claims that optometrists use “a complex model that purports to represent the visual system to ‘prove’ that a given intervention both is needed and will provide a given result.” This portrays a very negative image of behavioural optometry. He concluded his article, advising ophthalmologists “to avoid those eye exercises that have not proved effective and that may be unnecessarily costly”.4
This is not the first comment of its kind; ophthalmology has been discrediting vision therapy for years. An article published in 1972 entitled The eye and learning disabilities14 denied any relationship between vision and learning. Although the inaccuracies of this article were exposed, further articles continued to depict vision training as controversial, unscientific, and virtually irrelevant to learning, eg. Is vision therapy quackery?15 This demonstrates the negative viewpoint from other medical professions to behavioural optometry and reflects a lack of success within the medical field.
Measures of Success
The experiences of behavioural optometry within the general community provide measurements of its success. Resources from behavioural optometric organisations, online discussion forums, and the mass media also provide us
with an idea of how this form of
treatment is perceived.
ACBO publicly states on its website that it may be able to assist with learning difficulties, traumatic brain injury, sports vision, and binocular vision dysfunction. There are also pamphlets available, explaining the benefits of vision therapy, and the nature of certain conditions, eg. “Don’t give up on your child!” or “I was nearly a dropout”.
Online forums created by organisations such as visionandlearning.org and Parents Active for Vision Education (P.A.V.E). support the practice of behavioural optometry and the benefits it offers.
These organisations aim to increase public awareness of the impact of vision on learning organisations and list dozens of success stories of vision therapy helping children improve their academic results
as well as their quality of life.16,17
The success of behavioural optometry among parents is unsurprising given the nature of its techniques. Behavioural optometry offers an answer to parents who question why their children may have difficulties learning. It also provides a non-invasive potential solution, improving academic results and quality of life.
The success and controversy of behavioural optometry has been discussed within the media. One prominent example receiving media attention was the case of Sue Barry, also known as “Stereo Sue”, who published a book describing the success she gained in obtaining stereopsis despite being esotropic since a young age.18
Many ophthalmologists had given up on Sue and told her there was nothing that could be done for her esotropia, yet despite this, she commenced intense vision training through a behavioural optometrist and finally achieved stereoscopic vision, which provided her with the overwhelming sense of joy from being able to see the world with two eyes. Ms. Barry received hundreds of letters from hopeful strabismic patients, who had acquired a newfound hope through the success of her vision training.
Conversely, an article in the New York Times, ‘Concocting a Cure for Kids with Issues’, discussed the basis of vision therapy, the antagonism from ophthalmic and paediatric professionals as well as several success stories.19 The article argued that techniques employed in behavioural optometry such as providing low powered spectacle lenses may have no effect on a child’s vision. The article continued on to argue that due to the Hawthorne effect, the additional positive attention provided may change and improve behaviour in children. Despite the opposition exhibited from other medical professions, behavioural optometry still retains success in the general population.
The level of scientific evidence behind behavioural optometry is often debated. However, behavioural optometry has been used to treat a number of conditions including accommodative and convergence disorders, myopia progression, learning difficulties, attention deficit disorder and neuro-rehabilitation after trauma or stroke. A search within scientific literature databases reveals that there is limited evidence in terms of randomised clinical trials (RCT) to support the efficacy of behavioural optometry in treating these conditions. The only RCTs that have been conducted involve convergence insufficiency and accommodative insufficiency.20
Birnbaum et. al. proved that convergence insufficiency was a treatable condition through a RCT consisting of three groups: office based exercises, home-based exercises and no therapy.19 The results suggested that office-based exercises, such as those used by behavioural optometrists, were effective in treating convergence insufficiency. Accommodative insufficiency, as one of the first binocular vision problems to be recognised and treated by behavioural optometrists, has been thoroughly investigated in the past 20 years with a widely accepted treatment plan consisting of a combination of vision therapy and plus lens reading glasses.21 Brautaset et. al. demonstrated that plus/minus lens flipper training is more effective in increasing accommodative amplitude than simply prescribing plus lens reading additions.19 This evidence supports the notion that regular eye exercises are an essential component of treatment for accommodative insufficiency.22
While in traditional optometry, assisting individuals with visual field defects from brain injuries would be limited, advocates of behavioural optometry propose the use of visual therapy in order to improve reading ability and quality of life. A review of several studies with varying levels of internal validity, suggests that while vision therapy has been shown to provide subjective improvements in these individuals, objective measures such as scanning laser ophthalmoscopy and Goldmann perimetry do not suggest improvement.23 In addition, advocates of behavioural optometry suggest that they are able to play a role in improving and enhancing the underlying dysfunctions in visual function that could possibly lead to learning difficulties. However, according to a joint statement from the American Academy of Paediatrics, there is limited evidence to suggest that visual dysfunctions could lead to learning difficulties.24 While behavioural optometry has demonstrated success in aiding individuals, the absence of scientific evidence supporting efficacy in some conditions has resulted in antagonism from the medical community.
While double-blind RCTs are considered the gold standard in scientific validation of therapies, it is recognised that it can be difficult, or almost impossible to conduct this type of design in vision therapy. Although the research that has been conducted in recent years certainly looks promising, further large-scale controlled trials must still be undertaken to support the efficacy claims made by behavioural optometrists, especially in the areas of dyslexia treatment and neuro-rehabiliation. Future trials may also indicate which patient groups
and age ranges are most suitable for various treatments.
Therefore we can conclude that while there is room for further research, behavioural optometry is definitely successful within the optometric field and currently expanding as more optometrists both locally and internationally adopt this way of diagnosing and treating. Additionally, public awareness of behavioural optometry and the spread
of conditions where it can be useful is also expanding.
Danny Kho is a 5th year B.Optometry/Science student at the University of New South Wales.
Monica Panjaya is a 5th year B.Optometry/Science student at the University of New South Wales.
Carina Trinh is the President of the Student Optometry Society 2011, and a 5th year B.Optometry/Science student at the University of New South Wales.
Figure 2: Timeline of the development of behavioural optometry.
Optometric Extension Program established by Dr A.M Skeffington and E.B Alexander.
A.M Skeffington publishes books detailing 21 points of analysis.
Keith Woodland introduces concepts from OEP to Australia.
College of Optometrists in Vision Development established.
Australasian College of Behavioural Optometry (ACBO) established.
The first International Conference of Behavioural Optometry.
British Association of Behavioural Optometry established.
1. Australasian College of Behavioural Optometry c2010 [cited 2010 Aug 20] What is behavioural optometry? http://www.acbo.org.au/articles/100-what-is-behavioural-optometry.
2. Birnbaum MH. Behavioural optometry: A Historical Perspective. J Am Optom Assoc 1994 Apr 65; (4):255-64.
3. Parks MM. Strabismus care: past, present and future. Doc Ophthalmol 1973 Feb 21; 34(1):301-15.
4. Helveston EM. Visual training: current status in ophthalmology. Am J Ophthalmol 2005 Nov; 140(5):903-10.
5. Rosenfield, M, Gilmartin, B.(1998) Myopia and Near Work. Elsevier Health Sciences.
6. Skeffington AM. Introduction to Clinical Optometry. United States of America: Optometric Extension Program Foundation, Inc., 1988.
7. Holland K. The Science of Behavioural Optometry [monograph on the Internet] Optometry Today; 2002 [cited 2010 August 1] Available from: http://www.optometry.co.uk/articles/docs/0313084cb96b945351825ca306f9e3d0_holland20020308.pdf.
8. Godnig EC. The Tachistoscope Its History & Uses. J Behav Optom 2003; 14(2): 39-42.
9. Howell ER. Where is the “Magic” in Vision Therapy? Proceedings of the 6th International Congress of Behavioural Optometry, 2010 Apr 10; Ontario,
10. Williams RA. Behavioural optometry going international. J Behav Optom 1991; 2(8):212-15.
11. Veronika Kypros, Webmaster of the ACBO 10 Aug 2010 [cited Aug 20]).
12. Caroline Hurst, Chairman of BABO 2 Sep 2010
[cited Aug 2]).
13. Barrett BT. A critical evaluation of the evidence supporting the practice of behavioural vision therapy. Ophthalmic Physiol Opt 2009 Jan; 29(1):4-25.
14. Flax, N. The Eye and Learning Disabilities, J. Am. Optom. Assn., Vol. 43, No. 6, 1972.
15. Koller H. Is vision therapy quackery. Review of Ophthalmology March:38-49, 1998.
16. Parents Active for Visual Education. San Diego: c2000-2010 [updated 2010; cited 2010 Aug 12]. Project 10 000 success stories. [about 23 screens]. Available from: http://pavevision.org/2009/12/24/project-10000-success-stories/#comments.
17. McMains M. C2000-2006 [updated 2006; cited 2010 Aug 12]. Vision therapy. [about 4 screens]. Available from: http://visionandlearning.org/whatisvt08.html.
18. Sacks O. Stereo Sue: Why two eyes are better than one. The New Yorker [newspaper online]. 2006 Jun 19 [cited 2010 Aug 12];[about 4 screens]. Available from: http://www.newyorker.com/archive/2006/06/19/060619fa_fact_sacks.
19. Warner J. Concocting a Cure for Kids with Issues. The New York Times [newspaper online]. 2010 Mar 10 [cited Aug 1];[about 17 screens] Available from: http://www.nytimes.com/2010/03/14/magazine/14vision-t.html?_r=2&pagewanted=all.
20. Birnbaum MH, Soden R, Cohen AH. Efficacy of vision therapy for convergence insufficiency in an adult male population. J Am Optom Assoc 1999; 70:225-232.
21. Brautaset R, Wahlberg M, Abdi S et al. Accommodation insufficiency in children: are exercises better than reading glasses? Strabismus 2008; 16:65-69.
22. Sterner B, Abrahamsson M, Sjostrom A. The effects of accommodative facility training on a group of children with impaired relative accommodation – a comparison between dioptric treatment and sham treatment. Ophthalmic Physiol Opt 2001; 21:470-76.