Frederick W. Brock (1899–1972), born in Switzerland, was an

optometrist Optometry is the healthcare practice concerned with examining the eyes for visual defects, prescribing corrective lenses, and detecting eye abnormalities. In the United States and Canada, optometrists are those that hold a post-baccalaureate f ...

, a major contributor to

vision therapy Vision therapy (VT), or behavioral optometry, is an umbrella term for alternative medicine treatments using eye exercises, based around the pseudoscientific claim that vision problems are the true underlying cause of learning difficulties, partic ...

, and the inventor of various vision therapy devices including the

Brock string A Brock string (named after Frederick W. Brock) is an instrument used in vision therapy. It consists of a white string of approximately 10 feet in length with three small wooden beads of different colors. The Brock string is commonly employed d ...

. Brock's approach to treating eye disorders was crucial in paving the way to overcoming an erroneous but long-standing

medical consensus Medical consensus is a public statement on a particular aspect of medical knowledge at the time the statement is made that a representative group of experts agree to be evidence-based and state-of-the-art (state-of-the-science) knowledge. Its main o ...

that

stereopsis Binocular vision is seeing with two eyes, which increases the size of the Visual field, visual field. If the visual fields of the two eyes overlap, binocular #Depth, depth can be seen. This allows objects to be recognized more quickly, camouflage ...

could not be acquired in adulthood but only during a

critical period In developmental psychology and developmental biology, a critical period is a maturational stage in the lifespan of an organism during which the nervous system is especially sensitive to certain environmental stimuli. If, for some reason, the org ...

early in life: neuroscientist Susan R. Barry, the first person to have received widespread media attention for having acquired stereo vision in adulthood, attributes him a central role in her recovery of stereopsis, a discovery which in turn influenced the prevalent scientific conceptions with regard to the neuroplasticity of the visual system.

Working method

Brock made many contributions to vision therapy, and his work focussed mainly on the application of vision training to the diagnosis and therapy of binocular dysfunction. Brock trained his patients with rich stereo images which closely resembled the natural environment, and favored these over the use of (simplified) stereographs. In a first session with a client, Brock would invest great time into finding a point at which the client already performed

binocular fusion Binocular vision is seeing with two eyes. The field of view that can be surveyed with two eyes is greater than with one eye. To the extent that the visual fields of the two eyes overlap, binocular depth can be perceived. This allows objects to b ...

, and Brock would refer to this point as his "point of attack" from which he would try to expand the range of positions in which fusion was achieved. He made use of the

peripheral vision Peripheral vision, or ''indirect vision'', is vision as it occurs outside the point of fixation, i.e. away from the center of gaze or, when viewed at large angles, in (or out of) the "corner of one's eye". The vast majority of the area in the ...

of his patients to lock binocular fusion, using his so-called "stereomotivator" to project large red/green anaglyphic stereo images onto a wall such as to stimulate very large receptive fields in the patients.S.R. Barry, in: He spoke against the use of an

amblyoscope A haploscope is an optical device for presenting one image to one eye and another image to the other eye. The word derives from two Greek roots: ''haploieides'', single and ''skopeo'', to view. The word is often used interchangeably with stereoscope ...

during training, because in his view the patient needed to take the correct binocular posture (aiming the two eyes such that they simultaneously look at the same target in space) when fusing, otherwise the training would not be likely to succeed. Aside the well-known

with which patients practice binocular accommodation and

vergence A vergence is the simultaneous movement of both eyes in opposite directions to obtain or maintain single binocular vision. When a creature with binocular vision looks at an object, the eyes must rotate around a vertical axis so that the proj ...

, he frequently used images of red/green anaglyphic rings for diagnosis and training.

Influence

Brock's methods have been widely applied in vision therapy. Susan Barry's vision therapist Theresa Ruggiero used Brock's methods and approach in her own vision therapy sessions. Her therapy led Barry to achieve stereo vision, disproving the medical community's consensus that stereo vision in adult life was inachievable. Barry later wrote a paper on Brock's work that was selected as the best published paper in the

Journal of Behavioral Optometry The ''Journal of Behavioral Optometry'' was a peer-reviewed medical journal published by the Optometric Extension Program Foundation. It covered clinically relevant behavioral, functional, and developmental aspects of the visual system The v ...

in 2011.Susan Barry: Meribeth E. Cameron Faculty Award for Scholarship
,

Mount Holyoke College Mount Holyoke College is a Private college, private Women's colleges in the United States, women's Liberal arts colleges in the United States, liberal arts college in South Hadley, Massachusetts, United States. It is the oldest member of the h ...

, 5 March 2013 (downloaded 24 July 2013)

Personal life

Born in Switzerland in 1899, Brock spoke German at first, but switched to English as his main language after he moved to the United States in 1921 at the age of 22. He saw an analogy between such a transition of languages and the mental transition that is required of a strabismic person. He had some own experience with the strabismic way of seeing, reportedly having had brief moments of intermittent diplopia himself. For most of his professional career, he practiced in Staten Island, NY. Brock published more than 100 papers, journals, manuals, monographs and lecture notes. The Frederick W. Brock Memorial Award for Excellence in Vision Therapy is awarded in his honor.

Working method

Influence

Personal life

References

Further reading