How does sensory development in dogs and wolves relate to behavioral optometry?

Genetically, dogs and wolves are the same species. They are able to hybridize, will happily do so given the opportunity, and the offspring are healthy and fertile. In spite of their genetic similarities, behaviourally speaking they are very different. To tame a wolf is practically impossible. Why this is when they're technically not even a separate species from "man's best friend" has long been a puzzle. Now, doctoral research by evolutionary biologist Kathryn Lord at the University of Massachusetts Amherst suggests the different behaviors are related to the animals' earliest sensory experiences and the critical period of socialization. Below a copy of the Science Daily article on these findings.

Until now, little was known about sensory development in wolf pups, and assumptions were usually extrapolated from what is known for dogs, Lord explains. This would be reasonable, except scientists already know there are significant differences in early development between wolf and dog pups, chief among them timing of the ability to walk, she adds.

To address this knowledge gap, she studied responses of seven wolf pups and 43 dogs to both familiar and new smells, sounds and visual stimuli, tested them weekly, and found they did develop their senses at the same time. But her study also revealed new information about how the two subspecies of Canis lupus experience their environment during a four-week developmental window called the critical period of socialization, and the new facts may significantly change understanding of wolf and dog development.

When the socialization window is open, wolf and dog pups begin walking and exploring without fear and will retain familiarity throughout their lives with those things they contact. Domestic dogs can be introduced to humans, horses and even cats at this stage and be comfortable with them forever. But as the period progresses, fear increases and after the window closes, new sights, sounds and smells will elicit a fear response.

Through observations, Lord confirmed that both wolf pups and dogs develop the sense of smell at age two weeks, hearing at four weeks and vision by age six weeks on average. However, these two subspecies enter the critical period of socialization at different ages. Dogs begin the period at four weeks, while wolves begin at two weeks. Therefore, how each subspecies experiences the world during that all-important month is extremely different, and likely leads to different developmental paths, she says.

Lord reports for the first time that wolf pups are still blind and deaf when they begin to walk and explore their environment at age two weeks. "No one knew this about wolves, that when they begin exploring they're blind and deaf and rely primarily on smell at this stage, so this is very exciting," she notes.

She adds, "When wolf pups first start to hear, they are frightened of the new sounds initially, and when they first start to see they are also initially afraid of new visual stimuli. As each sense engages, wolf pups experience a new round of sensory shocks that dog puppies do not."

Meanwhile, dog pups only begin to explore and walk after all three senses, smell, hearing and sight, are functioning. Overall, "It's quite startling how different dogs and wolves are from each other at that early age, given how close they are genetically. A litter of dog puppies at two weeks are just basically little puddles, unable to get up or walk around. But wolf pups are exploring actively, walking strongly with good coordination and starting to be able to climb up little steps and hills."

These significant, development-related differences in dog and wolf pups' experiences put them on distinctly different trajectories in relation to the ability to form interspecies social attachments, notably with humans, Lord says. This new information has implications for managing wild and captive wolf populations, she says.

Her experiments analyzed the behavior of three groups of young animals: 11 wolves from three litters and 43 dogs total. Of the dogs, 33 border collies and German shepherds were raised by their mothers and a control group of 10 German shepherd pups were hand-raised, meaning a human was introduced soon after birth.

At the gene level, she adds, "the difference may not be in the gene itself, but in when the gene is turned on. The data help to explain why, if you want to socialize a dog with a human or a horse, all you need is 90 minutes to introduce them between the ages of four and eight weeks. After that, a dog will not be afraid of humans or whatever else you introduced. Of course, to build a real relationship takes more time. But with a wolf pup, achieving even close to the same fear reduction requires 24-hour contact starting before age three weeks, and even then you won't get the same attachment or lack of fear."

This struck me as yet another wonderful example of the power of nurture over nature. The same (if we are talking about one person or animal in particular) or nearly the same genes can have radically different outcomes depending on differences in the developmental trajectories. Even though dogs and wolves are not even a different species, they elicit radically different behavior due to different sensory development in the critical period of socialization.

A lot of people have argued nothing can be done about binocular vision disorders, in other words: deficient sensory development in humans, because they have been encoded during the 'critical period'. There is a great deal of irony to this because often the most vigorous and curious children tend to develop vision imbalances. Those who try to move faster than is good for them or are forced to do so by their environment. The first will be last... Poor development of visual skills and whether or not the problem is correctly diagnosed and treated with Vision Therapy has far reaching effects on the overall development of a person and can make the difference between a friendly, productive, well-adjusted citizen (let's say a dog) or in extreme cases a frustrated, learning disabled, violent criminal with serious mental issues (let's say a wolf).

Now that's were humans are different from animals. We are self-conscious and like to think of ourselves as intelligent giving us the power to self-direct. Long has been thought, based on animal experiments, once something went wrong in the critical period of vision development there's no way to correct it. This is true for animals because they don't have an analytical mind allowing for intelligent action and long term planning. In humans however, the critical period for the development of a lazy eye for instance isn't the same as the critical period for rehabilitating that eye. That can be done life-long by means of planned and motivated intervention by that individual if he is aware that option is available. Well, the option is available! People can 'nurture' their own way out of visual brain disorders by means of vision therapy and a tremendous amount of self-awareness and perseverence. People can make a diliberate change when handed the tools to do so.

My granddad is a 3D nerd

Throughout his life my granddad has always been very fond of photography and until this day he tries to keep up with current developments in digital photography. Back in his early days he had one of the first cameras and even one of the first stereocameras. It's safe to say he was an early adopter of the 3D technology back in the fifties. This makes for interesting photos and material.

He has this ancient case containing two frame slides with pictures he took during his lifetime. Even pictures of my grand grand father. Maybe I won't just acquire stereovision, but I'll be able to see dead relatives in 3D. That's something I litterly can't conceive yet...

 I also found one of these is his house. A Stereo Viewer made by Underwood & Underwood of New York. Including a wooden handle and a stereoscopic picture. The viewer has two lenses at a set distance in an aluminum frame. The pictures can be moved horizontally in order to focus them. These devises became popular in the middle of the 19th century. This is a Holmes type stereoscope, named after its inventor, Oliver Wendell Holmes (1860). 

It strikes me as terribly ironic that my granddad was so engaged with stereophotography while I have no idea of what it must feel like. I spent a lot of time with him last year and he told me that when I developed the squint as a child, it had crossed his mind back then 'that some kind of intensive training might correct it'. Of course, it was just a hunch he had and he must have thought 'Who am I to contradict doctors and parents alike?'. He didn't have any real knowledge about the subject of vision, just a bunch of stereoscopes and common sense. Something that is in short supply apparently.  Irony, so much irony...

Book Review: Suddenly Successful: How Behavioral Optometry Helps You Overcome Learning, Health And Behavioral Problems

One word: mindboggling. Anyone with eyes should read it and honestly I had some problems curbing my enthusiasm. Having discovered about Vision Therapy through the internet and Susan Barry’s 2009 publication ‘Fixing my Gaze’ which is equally mind blowing and emphasizes the beauty and advantages of having stereovision and the brain processes involved in acquiring it for people with long standing strabismus as myself, you would think this form of life changing treatment is fairly new. Well, nothing is less true… This 1991 publication totally bursts that bubble.

The main author of ‘Suddenly successful’ is Hazel Richmond Dawkins. A seasoned writer who was legally blind in one eye for fourty years due to amblyopia before finding out about behavioral optometry. She must have been so astonished that no doctor had ever told her about this ‘simple’ low tech cure called vision therapy that she researched the topic to its core. Sounds familiar… She was helped by two optometrists writing this book. This accessible yet profound publication links perfectly detectable and treatable vision imbalances to learning disabilities (concentration problems, reading problems, dyslexia, ADD, ...), juvenile delinquency, psychiatric problems (schizophrenia, depression, alcoholism…) and chronic health problems (migraines, headaches, muscle aches, balance problems, travel sickness, tension, light sensitivity, teeth-grinding,…). This is done in a convincing fashion with referenced facts and anecdotes. Optometric vision therapy will not rid us of all such problems, but it will be effective when problems are related to the way your visual system works or rather malfunctions.

The numbers mentioned when talking about criminality and reducing recidivism with optometric vision therapy are downright spectacular. ‘The success rate for reducing the level of recidivism in the United States is not high. The norm for re-arrest is 50 to 60 percent. … A six year follow-up study of over 500 juveniles showed the re-arrest rate went from 45 percent to 16 percent. Findings from the programs supported earlier studies made by optometrists David Dzik of Tennessee, Roger T. Dowis of Colorado and Joel Zaba of Virginia. … As this federally funded study has shown, learning problems and antisocial behavior change after optometric vision therapy. Once some harmony and balance exists in the vision system, then the youngsters can begin to benefit from traditional education.’.

The chapter about psychiatric health in relation to vision problems is no less spectacular. When visual development gets derailed at one point without proper treatment this spills over into other brain functions and manifests itself in all kind of ways. Every millisecond the brain receives 3 billion impulses. One billion from one eye, one billion from the other and one billion from the rest of the body. Half of the brain is involved in the activity of vision. This doesn’t only involve eye sight but also how your eyes function in relation to the rest of your body. The role of vision development in overall brain development and mental as well as physical health is substantial. When the vision system is brought out of balance as an adaptation to environmental or physical factors the whole brain is affected. By correcting this imbalance by appropriately stimulating the vision system by means of optometric vision therapy a negative down turn can be avoided and instead cause a positive domino effect that can transform the entire brain along with its owners performance and quality of life.


Further the book provides a history of how and why ophthalmology, orthoptics and behavioral optometry have grown apart. It’s a sad example of how the best idea or best practice does not always become the norm. I quote ‘Any attempt to compare orthoptics with optometric vision therapy is like comparing the Wright Brothers’ aircraft with the space shuttle. Both are forms of transportation, but they are light years apart in concepts and results. So it is with orthoptics and optometric vision therapy. The concepts, practices and results are radically different (cure as opposed to no cure).’ This book was published one year after I was born and written even earlier, and still to this day eye care is dominated by primitive methods providing poor results. Strabismus hits about 4% of the population and it is  curable in the majority of cases even though many ophthalmologist resist the cure till this day causing sorrow to millions. Sadly, the story doesn’t end with those 4%. About 20% of the population, or 1 in 5 people, suffer from a less visible vision imbalance (phoria: eyes sometimes deviate instead of tropia: eyes deviate at all times) impeding them from living freely and up to their potential. This manifests itself with a myriad of symptoms which sometimes don't even seem to be eye related. Yet, the majority of cases go untreated. Incomplete vision screenings testing only eye sight at about 10m distances (as opposed to a comprehensive vision exam testing at least 21 visual skills) along with misconceptions amongst many ophthalmologists are the biggest obstacles to overcome in order to get the eye care you need. Often the ones in need are children who can’t express the problem and can’t look out for themselves… Or adults with reading problems, often in pain, who almost have to become optometrists themselves in order to find a solution to their problem. This book stated the problematic situation in 1991 and apparently it wasn’t even a new problem back then. How the hell is this possible? Who is holding these people accountable? It’s outrageous, since making comprehensive eye examination mandatory has significant capacity to expand human potential and improve society as a whole. 

Throughout the book many vivid stories demonstrate the science and how much work is still to be done to get behavioral optometry universally accepted. One of the anecdotes tells the story of Luci Baines Johnson, daughter of the then US vice president, who had consulted all kinds of physicians, psychiatrists, ophthalmologists, educators to no avail. Finally she and her parents ended up consulting Janet Travell MD, President Kennedy’s personal physician, who suggested it might be a vision problem that is keeping her from performing adequately and living a healthy life. After being treated by a behavioral optometrist, she became a enthusiastic advocate of optometric vision therapy. “If my family, with its wealth and power, could seek so long and unsuccessfully for the right answer to my problem, how many others throughout our country seek this help? … The key to a better society is education, the key to a better education is better vision. If you don’t have that key, you can’t open the door to a better life.” Luci Baines Johnson. 

Amidst all the calamity it is also shown that even people with high performing vision systems who don't experience severe problems can benefit from optometric vision therapy. Top athletes use sports vision training to give them that extra edge to compete. Testimonies illustrate how Olympic hockeyplayers, volleyball players and others improved their overall performance with vision training.
'Compensating for a visual deficiency by relying on another sense takes its toll as competition becomes tougher. By the time an athlete reaches the Olympics, the split second it takes to compensate for a visual deficiency may mean the difference between a gold medal and sixth place. ... The four (Olympic) volleyball players who received the extensive vision care had hitting percentages in the 20 percent range when vision sessions began. After the therapy, their hitting percentages moved to 40-50 percent.'

Aside from giving you a broad yet insightful idea of what kind of vision imbalances (astigmatism, nearsightedness, farsightedness, strabismus, lazy eyes or often a combination) there are and exactly how optometric vision therapy and the right motivation can cure or improve them, this book puts you on your way to finding a behavioral optometrist practicing optometric vision therapy (pre-internet) for a comprehensive eye exam. Last but not least, some practical tips to stimulate visual development in children and adults are provided. Reading this book can greatly benefit you and others around you.

Copies available at the Optometric Extension Program Foundation 

Related articles on this blog:
- Visual Impediments to Learning: What's it going to be? Your health or your education?