Doubling the Rate of Neurologic Development in Down Syndrome: a Pilot Study Patrick James Baggot, M.D. Rocel Medina Baggot, M.D. Conrad Russell Chao, M.D.

Dr. Baggot’s paper on Trisomy-21 children as of June 2016

Doubling the Rate of Neurologic Development
in Down Syndrome: a Pilot Study
Patrick James Baggot, M.D.
Rocel Medina Baggot, M.D.
Conrad Russell Chao, M.D.

Introduction:

After World War II, in which physical therapist Glenn
Doman fought Nazi Germany as a decorated American Army
commander, he and his colleagues developed methods
and exercises for the neurodevelopmental rehabilitation
of children. These techniques were used for children
with cerebral palsy, autism, developmental delay, Down
syndrome, and a wide variety of other neurodevelopmental
disorders. Doman and colleagues opened the Institutes for
the Achievement of Human Potential (IAHP) in 1955, and
published their work in 1960 in the Journal of the American
Medical Association.1

The use of educational and behavioral interventions
to improve long-term neurologic outcomes is a very
controversial area in developmental pediatrics. While some
studies support their efficacy,2-3 other studies failed to
demonstrate benefit.4-5 Overall, there is a paucity of data
from which to draw definite conclusions. Many of the studies
were performed in the remote past, and surprisingly few
new data have been published since.

Recently, von Tetzchner et al.6 published a study on
the IAHP method, the first in more than three decades,
in the Journal of Developmental Neurorehabilitation. Von
Tetzchner’s article contained some flaws that may have
obscured a real benefit of treatment. The groups were very
small (17 and 18). In each group there were many different
diagnoses, including genetic syndrome, cerebral palsy (CP),
epilepsy, and developmental delay, spanning a wide range
of severity. These factors may have increased variance so
much as to obscure a real benefit. Additionally, 13 different
developmental exams were used, and only one child in the
IAHP group was treated before age five. This is contrary to the
IAHP method, which recommends treatment from an early
age. It suggests that von Tetzchner’s group did not understand
the method well enough to make a valid replication. Finally,
the parents felt strongly that the IAHP method was better,
and this was highly statistically significant. However, this
was not mentioned in the conclusion, which stated that
“the substantial claims of superiority compared to other
interventions made by IAHP…are not supported, but parents
appear to be met in a positive manner in these programs.”6
The current study seeks to correct the flaws of von
Tetzchner’s study. Instead of many and nebulous diagnoses,
only one, Down syndrome, was used. Down syndrome can
be verified either by physical examination or a chromosomal
analysis. In von Tetzchner’s study, the number of different
developmental profiles used (13) is almost great as the
number of subjects (17-18) in each group. In the current
study, only a single developmental profile is used. All beforeand-after developmental examinations were done by the
professional staff of IAHP, using the developmental profile
of the IAHP. The treatments were taught by IAHP staff to the
parents. The number of subjects was greatly increased from
17-18 to more than 200. Variance between subjects, which
can obscure conclusions, was further reduced by having
each child serve as his own control.

Materials and Methods

The database consisted of a 25-year longitudinal cohort
extending from 1990 to 2015, containing 248 children with
Down syndrome. Of these, 24 were lost to follow-up, and
eight had birth or examination dates that were unclear,
making time calculations unreliable. Remaining for analysis
were 216 of the 248.

Exercises

The program uses many developmental exercises, which
have been detailed in books.7-10 Important components
include: movement exercise, progressing from crawling at
an early age to running; passive exercises for those not able
to crawl yet (patterning); early reading with flashcards; early
mathematical education by counting dots on flashcards;
balance and athletic activities; nutritional optimization
(elimination, rotation, or other diets); and avoidance
of antiepileptic drugs that hinder brain development.
Functional IAHP methods to stimulate brain development
are explained below.

Crawling on the floor is encouraged. A minimum of four
hours daily is recommended. Developmental milestones in
crawling are for the infant to elevate itself on the forearms,
and then on the wrists; to lift up its head to see where it is
going; and to develop convergent gaze. Close contact with
the floor encourages convergent gaze development, which
is necessary for reading because without it one has diplopia.
Stabilizing the body develops arm strength, chest strength,
and breathing strength and control, which is necessary for
speech. Crawling demands significant athletic exertion from
infants, evoking growth hormone, which is beneficial for
brain development.

Patterning is teaching a child how a motor activity feels,
or teaching the sensory portion of a motor movement.
When teaching one’s child to draw, one could place the
pencil in the child’s hands, and then move the child’s hands
to draw. Many parents teach their children how to ride a
bike by placing the child on the seat and moving the bike
passively, helping the child with balance. Most parents
have done patterning.

If children have difficulty crawling, then patterning is
appropriate. To teach the child to crawl by passive movement
requires a team of three. The team moves the head and each
limb in proper sequence. If one did not understand the
purpose, patterning would appear bizarre. Crawling in a
cross-pattern requires coordination of head, arms and legs.
In IAHP experience, it promotes development.

Brachiation is moving across a jungle gym (ladder parallel
to floor) while hanging from it by the hands. It recalls the
movement of primates, before they descended from the
trees to walk on the ground. It demands strength in the arms,
accurate vision and hand placement, and balance. Swimming
develops arm strength and breath control. Swimming
stimulates brain development, especially at a young age.
Beyond crawling, children may walk, walk on uneven
surfaces, climb and descend stairs, walk on logs, and run.
These develop balance. Newborns are taught balance
passively by swinging them through the air or moving them
on a pad, replicating the movements airplanes make, such
as pitch, yaw, roll, etc. Running is a strong stimulus for brain
development. IAHP encourages all sports, dance, balance
moves, and gymnastics. From the IAHP perspective, exercise
is more about the brain than the limbs.

Many children with neurologic disabilities have small
stature and small lung volumes. The children often do
a treatment called “masking” for one minute per hour.
Breathing from a special mask raises carbon dioxide, which
is considered to stimulate lung development, chest volume,
and cerebral vasodilatation. In IAHP’s experience, masking
may enhance chest size, stature, and head circumference.
Reading may be taught at ages 4-6 months, one word at
a time. Two-inch bright red letters are printed on flashcards.
This is because newborns and infants have poor ability to
focus and converge. Their vision is blurry. The cerebral cortex,
which interprets the images, is also under development. In
this early stage, whole-word reading works best. Words are
more concrete and practical, while letters are abstract. The
children intuitively develop phonics while learning words.
Early reading demands that the infant visual cortex develops,
so as to perform at the level of an older child. Stimulating
cortical development is the point.

Math is taught early by counting red dots placed randomly
on a flashcard. While Arabic numerals are abstract, dots are
concrete and are more easily understood by infants. This
develops estimation, a right-brain form of math. Memorizing
multiplication tables is an approach to math more like
language—a left-brain approach. Thus, estimation develops
a parallel neural circuitry for mathematics.
It is most important to make learning fun. Children
naturally love learning. Parents have an urge to test the infant,
but infants don’t like being tested any more than adults do.
Short teaching interludes (five words) with minimum testing
are most effective.

Role of Staff and Caregivers

IAHP provides course work through which parents and
caregivers are taught the therapy. The parents and caregivers
are the therapists. IAHP staff teach the courses, counsel
the therapist-parents, and perform the developmental
examinations.

Developmental Assessments

The IAHP developmental profile is the Doman-Delacato
profile. Each patient received a thorough developmental
assessment by professional institute staff at initial
examination and first follow-up. In each case a global
neurologic age was determined. The chronologic ages were
determined from the dates of the examination and the
birth date. The ratio of global neurologic age (NA) divided
by chronologic age (CA) were determined. The ratio of the
global NA/CA was also determined at the first follow-up.
The median time from birth to initial exam was 16
months, and the average time was 26 months. The median
time from initial exam to first follow-up was 8 months, and
the average time was 13 months.

The Institutional Review Board of the IAHP approved the
study.

Results

Some patients ordered materials and began some
treatment, not wishing to wait for the initial assessment.
In the data, one can see some children doing surprisingly
well before IAHP treatment was formally begun. No Down
syndrome patients were normal or better without some form
of IAHP treatment. If some patients had not begun IAHP
treatment before the initial assessment, the results of the
study might have shown a stronger treatment effect.
Figure 1 illustrates one representative child who had
a NA of 7.89 at first exam at age 12.96 months. The initial
slope was 7.89/12.96=0.61. The slope of 0.61 means that the
child developed at a rate of 6 months of neurologic progress
per 10-month interval. At the first follow-up, the child had a
NA=21.04 months at a CA=20.46 months. The slope of the
second interval was (NA=21.04-7.89=13.15)/ (CA=20.46-
12.96=7.5 months). The second slope (13.15/7.5=1.75)
indicates that in the second interval, the child progressed
at a rate of 1.75, or 17 months per 10-month interval. Thus,
much more rapid developmental progress was made. For
an individual patient, this figure illustrates the difference
between slopes before and after IAHP treatment, which are
compared in the paired T-test (see below).

Figure 2 demonstrates that before treatment at IAHP,
subjects had made about half as much progress as would
normally be expected for their chronologic age. The figure is
square, with time in months equal on X and Y axes. If neurologic
progress in months were equal to chronologic time in months,
it would be represented by a line from the lower left corner to
the upper right corner of the diagram (slope=1.0). In Down
syndrome with standard treatment (before IAHP treatment) the
ratio of change (slope) in neurologic age (NA) over chronologic
age (CA) had a mean of 0.55 with a mode of 0.5. These results
with the developmental profile of the Institute agree with what
is generally known about Down syndrome. Generally, one
would expect a median intelligence quotient (IQ) of 40 with the
range of 25 to 70.

Figure 3 demonstrates that after IAHP treatment, the
rate of change (slope) of neurologic progress per unit time
more than doubled. The post-treatment average was 1.43,
and the mode was 1.2. Note that when the first follow-up
occurred at a very short interval after the initial exam, a line
representing the data would have a much steeper slope.
There are likely two reasons for this. One is that when stimuli
are novel (learning something new rather than something
old), brain development is promoted. A second reason is that
if, but only if, the method did really make a difference, a short
time interval accentuates the contrast between the standard
method and the new method.

Figure 4 plots the slopes of the rate of change of NA/CA
before IAHP treatment (when child was presumably receiving
standard treatment) and after IAHP treatment. The frequency
distribution of the rates of change is shifted to the right after
IAHP treatment, towards more rapid development. A paired
T-test was performed, comparing pre-treatment rate of
neurologic progress in each patient with the post-treatment
rate of neurologic progress in the same patient. The pretreatment rate of neurologic development was subtracted
from the post-treatment rate of neurologic development. If
the pre-treatment progress was equal to the post treatment
progress, this difference would be zero. If before IAHP
treatment, a child made 5 months of neurologic progress in
10 months, and after treatment began made 14 months of
progress in 10 months, the difference would be 9 months
greater progress in 10 months, or 0.9, nearly a doubling in
the child’s rate of development with treatment.

The mean difference was 0.87 months of neurologic
progress per month. The 95% confidence interval for the
difference was 0.75 to 1.0. These data indicate a strong
beneficial effect of treatment. Because the confidence
interval does not overlap zero, the results are statistically
significant. The P value is < 10-15.

Discussion

In the Middle Ages in Europe, literacy was very uncommon.
Now most children in the Western world are expected to be
able to read and write. The reason for the difference is that
children now attend school six to eight hours per day. This
previously unforeseen treatment (all children attend school)
yields a previously unforeseen result (most children are now
literate).

According to an old paradigm, mentally retarded
children (now more often called intellectually or cognitively
disabled) are uneducable and incurable. In the old paradigm,

significant training would be a waste of time and effort.
Many children were institutionalized. According to a newer
paradigm, brain performance and intelligence are trainable.
If a child has an IQ of 50, it means that in 10 months’ time,
only five months’ progress is made. From the perspective
that training improves performance, the definition of the
problem also suggests the solution. This relationship makes
the recommendation for intensified treatment obvious in a
newer paradigm.

The effects of sensory stimulation and training on brain
development have been studied in animals. Beginning in the
1960s, Rosenzweig et al.11 spawned a large body of literature
on the effects of environmental enrichment on the brain.12
This term refers to functional methods to enhance brain
development. Environmental enrichment is composed of
complex inanimate and social stimulation including voluntary
exercise. Sensory inputs may be auditory, visual, tactile, and/
or social.13 Beneficial effects on brain development, seen
across multiple animal species including humans, include
enhancement of gross and microscopic brain morphology;
enhanced biochemical effects such as neurotransmitters and
neurotrophic molecules; enhanced physiologic processes
such as long-term potentiation; and improved behavioral
and cognitive processes such as learning, memory, problem
solving, and social interactions.12 Beneficial effects on brain
development can correct or improve prior neurologic insults
which result from sensory deprivation. They may remediate
or improve neurologic injuries, developmental delays, and/
or genetic syndromes (e.g. Down syndrome).12
Each of the components of environmental enrichment
has effects on the brain. Exercise stimulates neural
plasticity. This leads to enhanced neurogenesis, learning,
and cognitive performance.14 These enhancements are
seen in the cerebellum, cerebral cortex, hippocampus, and
globally.14 Exercise enhances intelligence and academic
achievement both in normal children and in those with
mental retardation.15 The benefit is increased when exercise is
combined mental training.16 Combined mental and physical
training can enhance neurogenesis (neuron replication)
and also neuron survival (limiting apoptotic loss of newly
elaborated neurons).

Different types of sensory stimulation also promote
neurogenesis, brain growth, cognition, and learning. Auditory
stimulation, ideally including the mother’s voice, stimulates
the auditory cortex so much that one can measure increased
thickness of the auditory cortex with cranial ultrasound.17
Visual sensory deprivation has profound negative effects
on brain development, and visual stimulation enhances
brain development.12 Tactile stimulation also enhances
brain development. Stimulation of one sensory channel (e.g.
tactile) stimulates development in other sensory (e.g. visual)
and motor modalities.18 In general, there is substantial crosspollination, such that stimulation of one sensory input or
motor skill enhances other sensory channels and motor
capabilities.12 These principles work across a range of species,

in normal and pathologic conditions.12 Development is a
physiologic process, and can be manipulated, just like pulse
or blood pressure.

The literature on environmental enrichment provides
a strong foundation in animal research for IAHP methods.
Adoption literature suggests environmental enrichment also
works in humans. In some institutions and orphanages, there
is an “institutionalization syndrome” composed of growth
delays, neuro-behavioral alterations, low IQ, disorganized
attachment, and impaired language abilities.19 These result
from neglect and diminished social and sensory stimulation.
Clearly, enhanced caregiving can strongly mitigate or
alleviate these effects of neglect.19

In one study, adoption from lower socioeconomic status
to higher socioeconomic status caused IQs to improve
from a mean of 77 to a mean of 98.20 Five other studies
confirmed that adoption from lower socioeconomic
status to higher socioeconomic status improved IQs and
cognitive performance.20 From these adoption studies, one
can conclude that intelligence is not immutable, but can
change. Functional stimulation (environmental enrichment)
can effect a significant improvement in intelligence,
development, and performance.

If a child suffered severe neglect and sensory deprivation,
the child could be mentally retarded. If at age 2 he achieved
one-year milestones, he would have a developmental
quotient of 50 (1/2 x 100). If the child was transferred to an
enriched or stimulating environment, he could make more
rapid progress. During a second period, the child might
make three years of progress in two years. During the second
period, the child might have had a developmental quotient
of 150 (3/2 x 100). This is called catch-up recovery. If at
age 4 the child had four-year milestones, he would have a
developmental quotient of 100 (4/4 x 100).

Some children were, in fact, severely neglected in
Romanian orphanages.21-22 One group had good results when
adopted before age 2. Evaluation before adoption revealed
severe global privation. Children suffered such severe
neglect that they were mostly below the third percentile
(mentally retarded). They had Denver developmental
quotients of approximately 50. The Romanian orphan
children were adopted into more loving and stimulating
British families. When reexamined at age four, they had
nearly complete recovery of cognitive abilities. They had
intelligence quotients in the 90s (normal) after recovery.
Thus, nearly complete recovery from mental retardation by
means of environmental enrichment has been demonstrated
in humans.21-22 Even moderate mental retardation could have
nearly complete recovery.

It was once thought that genetic, congenital, or
neurologic conditions were incurable, but more recently
this has been challenged.12 In a mouse model of perinatal
anoxic brain damage, environmental enrichment reversed
developmental delays in inhibitory interneurons.23 Similarly,
in a rat model of cerebral palsy, environmental enrichment

was able to prevent motor deficits.24 After noise-induced
impairment of the auditory cerebral cortex, environmental
enrichment rescued cortical neuron function25 and promoted
recovery of degraded auditory cortical processing.26 In
rats with cerebral cortical malformations, environmental
enrichment resulted in improved cognition.27
Studies in a mouse model of Down syndrome suggest
that exercise and environmental enrichment enhance
neurologic development and performance in this condition
as well. In the Ts65Dn mouse, environmental enrichment
led to more complex branching of the dendritic trees of
neurons,28 and exercise led to improvement in learning
abilities and hippocampal neurogenesis.29 Other studies
showed that environmental enrichment improved cognitive
abilities, synaptic plasticity, and visual functions,30 and that
it enhanced memory, cognition, visual system maturation,
hippocampal neural plasticity, and brain function.31
In a human study, multi-sensory massage enhanced
visual function and accelerated development in children with
Down syndrome.18 Prenatal and perinatal environmental
enrichment enhanced or restored anatomy, behavior,
learning, and memory in both animals32-33 and humans.34
Figure 4 shows that there is more variance in patients
using IAHP treatment than prior to treatment. This may be
because both children and parents may make greater or lesser
efforts at educational and treatment exercises. Also, in cases
where follow-up was short, the novelty of a new treatment
may accentuate the effect (Figure 3). When education is the
treatment, teaching something new has greater effect than
teaching something old. Novelty enhances the effect of
environmental enrichment.

Strengths of this study may include measures to reduce
variance. It is widely thought that standard therapy has no
significant benefit over no therapy. If similar measures were
used to reduce variance, standard therapy could be shown to
be superior to no therapy.

A potential weakness of this study is that all evaluations
were done at IAHP. In future work, independent outside
evaluation may strengthen the credibility of the conclusions.
This method should also be studied with longer follow-up
and across different diagnoses.

The rapid rate of improvement—more than doubling
in many children—might seem hard to believe, but it is
consistent with studies of adopted Romanian orphans and
animal studies.

Environmental enrichment uses the concept of holistic
cerebral stimulation, recognizing that to greater and lesser
degrees, most areas of the brain are connected one way or
another with most other areas of the brain. Depressing one
cortical function tends to depress other cortical functions to
some degree. Conversely, stimulating one cortical function
tends to stimulate other cortical functions to some degree.
This is illustrated in IAHP’s experience that children, even
those with profound brain injuries, can begin learning to read
at age 2 or even earlier and should be given the opportunity.

Reading stimulates other cortical functions including
speech. Rather than using speech as the foundation to learn
visual language, one could just as easily use visual language
foundation for speech.

Down syndrome has been thought of as primarily
a chromosomal problem. The chromosomal paradigm
focuses on genes triplicated by trisomy as a primary
set of pathophysiologic mechanisms. Alternatively,
Down syndrome could be re-imagined as a problem in
developmental neurobiology. This re-imagination of Down
syndrome changes the focus to different pathophysiologic
mechanisms, and points toward different treatments.

Conclusion

Down syndrome children have much greater potential
for development than many realize. Methods discussed here
for environmental enrichment should be studied for their
potential to enhance brain development in other conditions,
and in normal children as well.

Patrick James (“Paddy Jim”) Baggot, M.D., is an obstetrician/gynecologist
and medical geneticist, practicing as an independent physician in Koreatown,
Los Angeles, Calif. Contact: pjbaggot@hotmail.com. Rocel Medina Baggot
M.D., is an obstetrician/gynecologist. Conrad Russell Chao, M.D., is division
director of Maternal and Fetal Medicine at the University of New Mexico in
Albuquerque, N.M.

Conflict of Interest Statement: None of the authors has any real, potential,
or perceived conflict of interest to report relevant to the material of the article.
Acknowledgements: The tireless efforts of parents, caregivers and children are
gratefully acknowledged. The contributions of Teruki Uemora, Janet Doman,
past and present staff of IAHP and Glen Doman (deceased) are gratefully
acknowledged. This research was supported by the International Foundation
for Genetic Research (Michael Fund), which has now closed.

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