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Puppies enter the world as resilient, but still fragile and less than fully developed beings, unable to see, hear, walk or even regulate their own body temperatures. They are completely dependent on the dam, or on the intervention of human "nannies," for their very survival, as well as for their comfort guidance and development. From birth onward, their growth - in terms not only of size but also of physical, mental and emotional capability--develops at a pace that is nothing short of amazing.

Neurons - Use Them or Lose Them. Research has shown that, as in the case of human infants, birth releases billions of neurons in a puppy's developing brain. Dr. Bonita Bergin compares the neurons in a newborn puppy's brain to a "puppy book," filled with blank pages on which there are, as yet, no visible entries. Some of those pages only appear to be blank. In reality, they contain "pre-installed passages, written in invisible ink," representing the dog's instincts. Over time, the contents of those pages will become visible. Other pages truly are blank, and will be used to record the various sensations and experiences the dog will encounter throughout its life, as well as the dog's reaction to those sensations and experiences. Each new experience - for better or for worse - creates an imprint that will last for life on one of those pages. The earliest entries create perhaps the most marked and lasting impacts because they have little information with which to compete. As the puppy book fills up with more and more competing entries, the relative impact of each new experience -- unless especially traumatic or remarkable -- lessens. For example, a puppy whose first experience with humans is to have its paw trodden upon is apt to come away with a very different outlook toward people (i.e., a source of pain and fear) than would a more mature  dog who suffers the same painful misstep but whose puppy book by now contains many pages relating to humans, most of them positive and comforting.

Those neurons, or "blank pages," that are stimulated by sensory experience form connections to other parts of the brain, eventually becoming part of the pup's mental circuitry. Those used repeatedly, over time form patterns akin to "big, bold writing on the pages of the puppy book." Conversely, however, those neurons that are not used atrophy and are eventually pruned away. "To ensure optimum neural proliferation, akin to adding thousands of pages to that puppy book, early experiences need to be rich in love and sensory stimulation," Bergin writes.

To extend the analogy, consider the puppy book's blank pages to be encased, most of the time, in plastic sheet protectors. Writing on the plastic will leave some imprint, but absent pressure (e.g., trauma) or constant repetition, the mark will not be all that deep. However, when a puppy is undergoing a sensitive stage of development, the protective coating is stripped away, creating the opportunity to make a deeper and more permanent imprint. Again, that presents both an opportunity - to imprint deeply desirable traits, perceptions and behaviors -- and a risk, if mishandled, of traumatizing the puppy brain, embedding fear or aggression.

Enter ENS. During their first two weeks of life, puppies undergo one of those sensitive stages of development with respect to their thermal and tactile senses. Their senses of taste and smell also begin to develop. According to Dr. Carmen Battaglia, an expert in dog breeding, "During these first few weeks of immobility, researches noted that these immature and under-developed canines are sensitive to stimuli whichincludes thermal and tactile stimulation, motion and locomotion." Research not only on puppies, but also on other mammals from mice to chimpanzees and even humans, has shown that neonates removed from the nest for brief periods and exposed to mild tactile and thermal stress, in the form primarily of gentle handling, on a daily basis during this critical developmental period fared better as adults than their unstressed littermates.

The United States military deployed these observations in the early 1970s with its "Biosensior program," an effort to produce military working dogs of superior intelligence and super-keen scent and hearing abilities. Later popularized as the "Super Dog" program, Biosensor included the following five brief exercises, performed once daily, for a period of three to five seconds each, from the pup's third to 16th days of life. Though the Biosensor program itself came under justifiable criticism for some if its more outrageous claims and techniques, these five simple exercises live on under the title Early Neurological Stimulation, or ENS for short.

  • Tactile Stimulation - The pup is held in one hand, while the handler gently tickles the toes and webbing of any one foot with a cotton swab.

  • Head Erect - The pup is held straight up, perpendicular to the ground, with its head above the tail position.

  • Head Down - The pup is held securely in both hands with the head below the tail and pointed toward the ground.

  • Supine Position - The pup rests on its back in the palm of both hands with its muzzle facing the ceiling.

  • Thermal Stimulation - The pup is placed, belly down, on a damp towel that has been cooled in the refrigerator.

Multiple studies have now documented benefits to appropriately administered ENS exercises - properly stimulated neonates have been shown to mature faster, demonstrate better problem-solving performance and show improved resistance to cancer and infectious diseases. Stimulated pups also demonstrate improved cardiovascular performance in terms of heart rate and the strength of their heart beats and stronger adrenal glands. They have been found to be more active and display a greater propensity to explore their surrounding environment, as compared to their non-stimulated litter mates.

Perhaps most importantly , however, as adults, the stimulated pups were better able to withstand stress, and responded to stressors in a garduated fashion while unstressed littermates "responded in an 'all or nothing way.'" (Battaglia) Many undesirable canine behaviors  - aggression, separation anxiety, leash and barrier reactivity foremost among them - have their origins, in whole or in part, in the animal's inability to cope appropriately with stress.

In her work breeding and training service dogs, Bergin has supplemented the five core ENS handling exercises with additional brief, gentle exercises designed to take advantage of each critical stage of the neonatal puppy's development. As the puppy's sense of smell emerges in its second week, the handler nuzzles the puppy, places its nose close to their own, letting the handler's breath permeate its nasal passages. In weeks three and four, as the puppy's senses come alive, touching, rubbing and lifting of the pup's body parts continue, and new tactile sensations -- exposure to different textured flooring and surfaces, for example -- are introduced. As sound recognition develops in the third and fourth weeks, talking, high-pitched vocalizations and even singing to the pups is added. Not only do these exercises accustom the pup to human handling, they also help to develop the human-canine bond. As Bergin notes, "The ability of a dog to focus on people may well be found in the plasticity of its brain during these early weeks and months."

By weeks four to five, gradual and gentle exposure to a variety of noises from vacuum cleaners to thunderstorms, begins. Again, care is taken introduce each new sound in a calm and positive context and to ensure the pup is not scared. The puppy is never restrained, nor forced to move closer to the noise; instead, the handler remains calm and enthusiastic while the puppy chooses on its own to investigate or avoid the sound. "In time," writes Bergin, "the pup will model after your behavior and accept the sound as natural to the environment. 

From there, the puppy is ready to move on to the Socialization and Command and Cue (Obedience) segments of our JUMP START TRAINING program.

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