Preview content only
Content available from Current Developmental Disorders Reports
This content is subject to copyright. Terms and conditions apply.
COMMUNICATION DISORDERS (J SIGAFOOS, SECTION EDITOR)
Persistence of Primitive Reflexes in Developmental Disorders
&Mark F. O’Reilly
&Giulio E. Lancioni
#The Author(s), under exclusive licence to Springer Nature Switzerland AG 2021
Purpose of Review Neonates present with a number of primitive reflexes that typically dissipate in later infancy. Persistence of
such reflexes past infancy could indicate some type of developmental problem or compromised neurology and therefore might be
predictably associated with various types of developmental disorders. The present review sought to summarize key studies
investigating the persistence of primitive reflexes in individuals with cerebral palsy, attention-deficit/hyperactivity disorder,
autism spectrum disorder, and other developmental disorders.
Recent Findings Several studies have shown persistence of primitive reflexes in children with cerebral palsy, attention-deficit/
hyperactivity disorder, and autism spectrum disorder. Persistence of primitive reflexes varies in relation to the type and severity of
symptoms in cases of cerebral palsy and attention-deficit/hyperactivity disorder and with the presence of comorbid intellectual
disability in children with autism spectrum disorder. Primitive reflexes have also been shown to persist in adults with Down
Summary Assessing primitive reflexes may be useful for advancing the understanding and early detection of developmental
disorders. Additional research should seek to clarify the relation between the persistence of primitive reflexes and the type and
severity of developmental disorders, as well as seeking to identify possible reflex phenotypes. Persistence of primitive reflexes
might signal some type of developmental or neurological problem and may negatively impact motor development and learning.
Evidence-based interventions to address the persistence of primitive reflexes are lacking, and the development of these should be
a research priority.
Keywords Primitive reflexes .Cerebral palsy .Attention-deficit/hyperactivity disorder .Autism spectrum disorder
The behavioral repertoire of the neonate is characterized by a
number of distinct reflexes , which can be defined as “auto-
matic involuntary movements that occur in response to a stim-
ulus”[2, p. 1]. Indeed, there appear to be at least 27 different
reflex relations that are either present at birth or which emerge
within the first few weeks and months of life .
From a developmental perspective, human reflexes could
be classified into those that are durable versus those that are
more transient. Durable reflexes are generally retained
throughout the lifespan. Examples include the patellar tendon
(or knee-jerk) reflex, startle response, eye-blink, gag, sneez-
ing, and yawning reflexes [4–10]. Such reflexes, while essen-
tially permanent, can diminish or become more pronounced
due to aging, illness, disease, and various neuropathological
conditions . Consequently, assessing reflex strength has
long been recognized as an important part of the neurological
examination process .
There is another class of reflexes —present at birth or
emerging in early infancy —that usually have a more tempo-
rary or transient existence. These more transient reflexes have
been variously referred to as the primitive, neonatal, fetal, or
developmental reflexes [10–12]. Table 1describes a number
of primitive reflexes that have been frequently reviewed in the
medical and psychological literature [2,10–12].
This article is part of the Topical Collection on Communication Disorders
School of Education, Victoria University of Wellington, Kelburn
Campus Box 600, Wellington, PO 6140, New Zealand
School of Education, University of Newcastle, Newcastle, Australia
Department of Special Education, University of Texas, Austin, TX,
Department of Neuroscience and Sense Organs, University of Bari,
Current Developmental Disorders Reports
Table 1 Examples of primitive/atypical reflex reactions
Reflex Elicitation Reaction Usually disappears by
Asymmetrical tonic neck reflex (ATNR) Turning head/neck to the right or left One arm extends and the other flexes in
classic fencing pose.
4 months of age
Babinski Stroke sole of foot from heel to small toe and
then across to hallux with a blunt object
Hallux moves upward and other toes spread The Babinski sign represents an abnormal
reaction to elicitation of the plantar reflex
Galant/truncal incurvation reflex Stroking either side of the spine Child’s back flexes towards the stimulated
12 months of age
Glabellar Repetitive tapping on forehead Eyes close/blink Usually habituates within 5 taps. Persistent
blinking is atypical (Myerson’s sign)
Moro Sudden loss of support, such as a rapid
downward movement while being held
Arms spread slowly outwards and then return
to midline. Often accompanied by crying
3 months of age
Palmar grasp Stimulation of the palm by stroking or placing
an object in the infant’shand
Rapid closing of fingers in a grasping
4 months of age
Plantar Stroke sole of foot from heel to small toe and
across to hallux with a blunt object
Toes flex downward 2 years of age
Rooting Touching infant’s cheek, mouth, or lips,
especially with a circular motion
Turnstostimuluswith open mouth and often
3–4 months of age. Replaced by voluntary
movement to source
Snout Lightly touching or tapping outside of the lips
at midline when lips are closed
Protrusion or puckering (pouting) 3–4 months of age
Sucking Touch roof of mouth with nipple or finger, or
Child begins sucking 3–4 months of age. Replaced by voluntary
Symmetrical tonic neck reflex (STNR) With child on hands and knees, the response
is elicited when the child’s head flexes
inward or extends outward
Arms bend and legs extend with head flex.
Arms extend and legs bend when head is
9–12 months of age
Tonic labyrinthine reflex/extensor tone Holding infant up by the waist or chest
Tilting head back when infant is lying on back
Infant holds head up (superman pose)
Back stiffens and arches, legs stiffen and
feet/toes point forward
4 months of age
Curr Dev Disord Rep
Perhaps the most unique and intriguing aspect of primitive
reflexes is that they typically disappear, or are greatly dimin-
ished, within the first year or two of life . It has been sug-
gested that as the brain matures during infancy, primitive re-
flexes are increasingly inhibited and replaced by voluntary
motor responses . Rousseau, Matton, Lexuyer, and
Lahaye  argued that this diminishment or integration of
primitive reflex patterns during early infancy plays an impor-
tant role in children’s motor development. Grzywniak 
hypothesized that the transient nature of primitive reflexes
not only facilitates psychomotor development but also learn-
ing. For example, persistence of the asymmetrical tonic neck
reflex might make it more difficult for a child retain hands-on
engagement with their learning materials because the response
of turning the head to the right (or left) would elicit extension
(and flexing) of the respective arms.
Interestingly, while primitive reflexes usually dissipate in
early infancy, they have been reported to persist well beyond
infancy and even into adulthood in some typically developing
individuals [10,15,16]. Usually, however, the persistence or
reappearance of primitive reflexes is considered to be indica-
tive of some type of developmental or neurological problem
. One might therefore expect that individuals with varying
types of developmental disorders would evidence atypical re-
flex reactions, including long-term persistence of one or more
The next sections of this paper summarize key studies that
have investigated the persistence of primitive reflexes in indi-
viduals with cerebral palsy, attention-deficit/hyperactivity dis-
order, autism spectrum disorder, and other developmental dis-
orders. Key studies were located by searching three databases
(i.e., Google Scholar, ProQuest, and Medline) using a combi-
nation of terms (e.g., primitive reflexes and cerebral palsy or
primitive reflexes and autism). Studies had to provide objec-
tive data on the persistence of at least one primitive reflex in
individuals with cerebral palsy, attention-deficit/hyperactivity
disorder, autism spectrum disorder, or another clearly identi-
fied condition associated with developmental disorder. A re-
view of this type is intended to reveal the extent to which
primitive reflexes have been reported to persist in these pop-
ulations. Future research and intervention directions are con-
sidered in light of our review of these studies.
Cerebral palsy is a nonprogressive disorder caused by lesions
in the developing brain. The condition affects muscle tone,
posture, gait, and the ability to execute fluent motor move-
ment . Several studies have investigated the persistence of
primitive reflexes in persons with cerebral palsy [18–22]. In
an early influential study, Capute [18••] described the devel-
opment of a standardized measure (primitive reflex profile)
and showed its utility for rating the strength of seven primitive
reflexes (i.e., asymmetrical tonic neck, symmetrical neck, ton-
ic labyrinthine, positive support, derotational righting, and
Moro and Galant reflexes). In a subsequent study, Capute
et al. [19•] assessed 53 children with cerebral palsy using the
primitive reflex profile. They found that the resulting profiles
had discriminant validity with respect to children’s ambulation
ability. These two studies by Capute and colleagues [18,19]
point to the value of adopting a standardized assessment proto-
col as a means of quantifying the persistence and presentation
of primitive reflexes in children with cerebral palsy. The results
also indicated an inverse relation between the strength and the
number of primitive reflexes retained and a child’s ambulation
ability. This relation suggests that the extent to which primitive
reflexes persist may indicate the severity of the person’sneuro-
logical impairment and extent of functional limitations.
In another exemplary study, Dos Santos and Nogueira
[20•] assessed 124 children (3 to 17 years of age) with spastic
cerebral palsy for the persistence of four oral reflexes (i.e.,
rooting, suckle/swallow, biting, and gagging). They found
that retention of the biting reflex was associated with more
extensive motor impairment (i.e., spastic quadriplegia),
whereas this reflex was absent in persons with less extensive
motor impairment (i.e., hemiplegia). Retention of the biting
reflex was also associated with increased risk of oral diseases,
possibly because the biting reflex makes oral hygiene more
difficult. This study is important in showing that retention of
certain types of primitive reflexes might negatively affect the
performance of certain self-care routines and compromise
Smith, Gossman, and Canan [21••] examined the consis-
tency with which primitive reflexes could be elicited in 10
children with cerebral palsy. The children ranged from 3 to
6 years of age, and all were reported to have spastic quadri-
plegia. The researchers attempted to elicit five primitive re-
flexes (i.e., tonic labyrinthine, asymmetrical tonic neck, sym-
metrical tonic neck, crossed extension, and Moro reflex).
Attempts to elicit each reflex were undertaken when the chil-
dren were exhibiting different levels of alertness. In this study,
the children’s levels of alertness were measured using a be-
havioral state rating scale prior to attempting to elicit each
reflex. It could be hypothesized that one’s level of alertness
could impact on the perception of eliciting stimuli. The results
showed that the probability of eliciting a reflex was inversely
related to the child’s level of alertness. This finding suggests
that when children are in certain bio-behavioral states, they are
more likely to be responsive to eliciting stimuli. However, this
study might have been assessing something other than the
persistence of primitive reflexes, such as the children’sgeneral
susceptibility to stimulation under different bio-behavioral
states. In either case, the main finding of this study would
seem to highlight the importance of optimizing a child’sbio-
behavioral state to ensure an accurate assessment of reflexive
Curr Dev Disord Rep
behavior. Optimizing a child’s behavioral state towards higher
levels of alertness would seem especially pertinent for young
children and for individuals with more severe impairments
and/or comorbid intellectual disability, given that such indi-
viduals often show widely fluctuating levels of alertness .
In a large-scale prospective study, Zafeiriou et al. [22••]
assessed the primitive reflexes of 204 infants who were con-
sidered at risk for developmental disorders. Fifty-eight of
these children were eventually diagnosed with cerebral palsy,
22 with developmental retardation, and 124 were deemed de-
velopmentally normal at 2 years of age. Eight primitive re-
flexes (i.e., palmar grasp, plantar, Galant, asymmetrical tonic
neck, suprapubic extensor, crossed extensor, Rossolimo, and
heel reflex) were tested at 1, 3, 5, 7, 9, and 11 months of age
and again at 2 years of age. They found that children with the
spastic type of cerebral palsy showed slight retention of seven
of the eight reflexes, whereas children with the athetoid type
of cerebral palsy had a more marked retention of three specific
reflexes (i.e., the plantar, Galant, and asymmetric tonic neck
reflex). These data suggest that the number and strength of
retained primitive reflexes might be a “useful diagnostic tool
for early diagnosis of cerebral palsy”[22••, p. 151]. The spe-
cific primitive reflexes retained might also be useful in the
early and differential diagnosis of cerebral palsy, such as
distinguishing between spastic versus athetoid cerebral palsy
in infancy. In line with the results of Dos Santos and Nogueira
[20•], the results of this study point to an interaction between
the type and severity of cerebral palsy and the probability with
which different primitive reflexes are likely to persist.
Overall, the collective results of these studies [18–22]sug-
gest that many children with cerebral palsy are likely to pres-
ent with abnormal reflex reactions, including persistence of a
range of primitive reflexes. If the persistence of primitive re-
flexes does in fact most usually indicate some type of neuro-
logical problem , then it is perhaps not surprising that
many individuals with cerebral palsy will retain some primi-
tive reflexes, given that cerebral palsy is caused by lesions to
the developing brain . As Capute [18••] noted, the pres-
ence of an atypical reflex profile might therefore represent one
of the earliest detectable signs of cerebral palsy. With specific
reference to the persistence of primitive reflexes, Gulati and
Sondhi  have suggested that the extent to which primitive
reflexes are retained in late infancy might be a useful diagnos-
tic indicator of cerebral palsy.
While the available evidence reviewed in this section does
indicate a high retention of primitive reflexes in children with
cerebral palsy, there is considerable scope for future research.
For example, future research could explore a wider range of
primitive reflexes, beyond the relatively few that have been
studied to date. Additional research could also aim to tease out
relations between the persistence of various primitive reflexes
and the type and severity of cerebral palsy using larger sample
sizes that include children with different types and degrees of
cerebral palsy. Studies involving people with cerebral palsy
and comorbid intellectual disability would seem especially
important because a significant percentage of people with ce-
rebral palsy are also likely to have intellectual disability .
The presence of comorbid intellectual disability might be ex-
pected to influence the ease and speed with which primitive
reflexes are successfully replaced by functional (voluntary)
motor behavior, if in fact this developmental process is influ-
enced to some degree by a learning component.
Attention-deficit/hyperactivity disorder (ADHD) is character-
ized by distractibility, impulsivity, hyperactivity, and atten-
tional deficits that can interfere with learning and general ac-
ademic, social, and daily functioning . Although the cause
is unknown, ADHD is classified as a neurodevelopmental
disorder and probably has an organic/biological basis [24,25].
Several studies have examined the persistence of primitive
reflexes in children with ADHD [26••,27•,28–30]. Taylor,
Houghton, and Chapman [26••], for example, looked for reten-
tion of four primitive reflexes in a sample of 54 (7- to 10-year-
old) boys with ADHD in comparison to a sample of 55 typically
developing boys. The Moro, tonic labyrinthine, asymmetrical
tonic neck, and symmetrical tonic neck reflexes were assessed.
The results showed that children with ADHD had significantly
higher reactions across all four tested reflexes compared to the
typically developing children. Interestingly, retention of the tonic
labyrinthine and asymmetrical tonic neck reflexes was associated
with lower mathematical achievement among the boys with
ADHD. The authors suggested that this finding could highlight
“the potential significance of reflex retention in predicting vari-
ous learning and behavioural problems experienced by school-
In another relevant study, Konicarova and Bob [27•]
sought to determine whether persistence of the Moro and
Galant reflexes “play a role in Attention Deficit and
Hyperactivity Disorder (ADHD)”(p. 135). They therefore
tested for the presence of the Moro and Galant reflexes in 20
children with ADHD and 20 typically developing children.
There were equal numbers of same-aged (8 to 10 years of
age) boys and girls in both groups. The results are consistent
with those reported by Taylor et al. [26••]. Specifically, chil-
dren with ADHD showed significantly greater retention of
both the Moro and Galant reflexes compared to the typically
developing children. The authors suggested that persistence of
the Moro and Galant reflexes in ADHD might be due to a
complex process that disrupts the child’s ability to inhibit
and regulate neural functions. Somewhat surprisingly, no gen-
der differences were found. This is surprising because girls
with ADHD are generally less hyperactive than diagnosed
boys . The lack of gender differences could possibly
Curr Dev Disord Rep
indicate that the retention of primitive reflexes might have
some type of dysregulation effect on attentional processes
and perhaps also on the overall levels of motor activity.
A second study by Konicarova and colleagues con-
centrated on assessing persistence of the asymmetric tonic
neck reflex in a sample of 60 children with ADHD who,
importantly, had previously received ADHD medication.
The sample ranged from 8 to 11 years of age and consisted
of 33 boys and 27 girls. Thirty typically developing children
(8 to 11 years, 16 boys/14 girls) served as the comparison
group. All children were assessed for the presence of the
asymmetric tonic neck reflex. The severity of ADHD symp-
toms was also assessed using the children’s parent question-
naire (CPQ). Reflex reactions were rated on a 3-point scale
with higher scores representing a more pronounced reaction.
The CPQ  contains 93 items that ask informants to rate a
wide range of ADHD symptoms (e.g., conduct problems, anx-
iety, impulsivity–hyperactivity, and learning problems). In
this study, parents served as informants for the CPQ. The
authors reported a significant correlation between a child’s
reflex scores and ADHD symptoms. That is, children who
showed a more pronounced reflex response were also rated
higher on a majority of ADHD symptoms. The authors
interpreted these data as further evidence that the persistence
of primitive reflexes might indicate a disinhibition process
[27•], adding that inhibition problems might stem from “fron-
tal lobe damages”[29, p. 768]. Establishing the validity of this
claim will require additional research.
A third study by the Konicarova group  continued the
theme of comparing the persistence of primitive reflexes in
children with and without ADHD. This third study targeted
the symmetric tonic neck reflex and the asymmetric tonic neck
reflex. The study was unique in focusing only on girls who
had not received any ADHD medication. The samples includ-
ed 35, 8- to 11-year-old girls with ADHD and 30 similarly
aged girls without ADHD. As in the previous study , the
girls’reflex reactions were rated on Likert-type scales, and
parents rated the child’s ADHD symptoms using the CPQ
. The results were consistent with the team’s previous
findings [27•,29]. That is, children with ADHD showed
greater retention of primitive reflexes compared to typically
developing children. There was also a significant relation be-
tween the magnitude of the child’s reflex reaction and parents’
ratings of ADHD symptoms.
Overall, these studies suggest that school-aged children
with ADHD appear to be more likely to show persistence of
the Moro, tonic labyrinthine, asymmetrical tonic neck, and
symmetrical tonic neck reflex when compared to same-aged
peers without ADHD. This finding does not appear to be a by-
product or side effect of ADHD medication but does seem to
relate to the severity of ADHD symptoms. The greater persis-
tence of primitive reflexes among children with ADHD has
been suggested to stem from various possible factors, such as
failure to attain important developmental milestones [27•],
delayed cortical maturation , and problems with higher
levels of coordination of the central nervous system [29,33].
There are significant limitations in the ADHD/primitive
reflex literature. First, three of the four studies were generated
by the same research team, indicating the need for indepen-
dent replications. Second, a relatively narrow age range (8 to
11 years of age) has been included in these studies. It is there-
fore unclear if the primitive reflexes shown by the children in
these studies would persist into adolescence and adulthood.
Third, it is unclear if the primitive reflexes shown by school-
aged children have been retained since infancy or have
reappeared at some point after having disappeared in infancy.
The reappearance of primitive reflexes has been reported in
the elderly  and in persons with age-associated neurolog-
ical conditions, such as Alzheimer’s disease  and demen-
tia . Another gap in the ADHD/primitive reflex literature
is the lack of studies into the effects of retained primitive
reflexes on learning and more general areas of adaptive func-
tioning. An important limitation is that the studies to date have
attempted to elicit a relatively small number of reflexes.
Longitudinal studies by additional research teams in which a
wider range of primitive reflexes are assessed at regular inter-
vals (from infancy to adulthood) —and that measure a wider
range of learning and behavioral correlates —would be re-
quired to address these gaps and limitations. Comorbidity
would be another important variable to consider in future re-
search. This would be important given that ADHD is highly
concurrent with a range of other conditions, such as develop-
mental coordination disorder, learning difficulties, and
speech–language delay. It would be useful to determine if
there are differences in the persistence of different types of
primitive reflexes among persons with ADHD and varying
comorbidities. As yet, these types of relations have not been
widely examined in the literature.
Autism Spectrum Disorder
Autism spectrum disorder (ASD) is a developmental condi-
tion characterized by significant social skills and communica-
tion impairments, repetitive behavior, and a restricted range of
interests . ASD is considered to have a neurobiological
basis related to both genetic and environmental factors
impacting on the developing brain . Despite the increasing
numbers of children being identified with ASD and an explo-
sion of research into its nature, assessment, and treatment [37,
38], there is surprisingly little research into the persistence of
primitive reflexes in individuals with this diagnosis, although
this phenomenon has been widely recognized by autism re-
In an important early study, Minderaa and colleagues [43••]
reported on the persistence of primitive reflexes in samples of
Curr Dev Disord Rep
children and young adults with and without ASD. The ASD
sample (n= 42) consisted of 31 males and 11 females ranging
from8to28yearsold(meanage19.5 years). The control group
also had 42 people (30 males and 12 females) of comparable age
(range = 7 to 29 years old, mean = 19.6 years). Eight reflexes
were tested (i.e., snout, sucking, tactile rooting, visual rooting,
grasp, palmomental, glabellar, and nuchocephalic). Significant
differences were found with respect to the persistence of the
snout and visual rooting reflexes. Specifically, these two reflexes
were observed in 81% (male) and 78.6% (female) of the individ-
uals with ASD but only in 14.3% and 0% of the controls, respec-
tively. There were no significant differences on any of the other
reflexes. This probably reflects a floor effect as these reflexes
were reported for very few participants overall. In the ASD
group, age, gender, and use of medication were not significantly
related to the presence or absence of these primitive reflexes. In
an insightful discussion point, the authors speculated that the
high prevalence with which these two “oral”reflexes persisted
might have some significance for understanding the speech and
language deficits associated with ASD [43••,p.414].Inlinewith
this suggestion, it could be useful to test for persistent primitive
reflexes as part of a more general speech language assessment.
An interesting comparison by de Bildt et al. [44•] examined
the persistence of the visual rooting reflex in 155 individuals
with ASD plus intellectual disability versus 65 individuals
with intellectual disability only. Both samples were predomi-
nantly male (72.9% and 64.6%, respectively) and included a
fairly wide age range (3 to 20 years with a mean of 11 years).
In line with Minderaa et al. [43••], a significant percentage of
the ASD participants showed persistence of the visual rooting
reflex (43.9%). Indeed, the ASD plus intellectual disability
group was significantly more likely to have the visual rooting
reflex (43.9%) than the intellectual disability only group
(24.6%). However, for both groups, the reflex was more often
present in those with severe/profound versus mild/moderate
intellectual disability. Comorbid intellectual disability would
thus appear to be of relevance to the persistence of the visual
rooting reflex in people with ASD.
In a more recent study, Accardo and Barrow [45•] assessed
toe walking and the tonic labyrinthine reflex in a sample of 61
children newly diagnosed with ASD. The children ranged in
age from 19 to 36 months of age (median = 31 months), and
most (88%) were boys. The tonic labyrinthine reflex was rated
as abnormal in 23 of the 61 children (37.7%). Of significance
is that children with an abnormal tonic labyrinthine reflex
were twice as likely to be rated as having moderate to high
levels of toe walking. The researchers suggested that persis-
tence of the tonic labyrinthine reflex might hinder the devel-
opment of normal/fluent ambulation and “...contributeto
persistent toe walking”[45•,p.608].
In another more recent study, Chinelloa, Valentina Di
Gangib, and Eloisa Valenzab  studied 34 infants (15
boys/19 girls) ranging from 12 to 17 months of age. Infants
were tested for the presence of the grasping, rooting, and
sucking reflexes. They found an inverse relation between in-
fants’motor skill development (e.g., fine motor skills and
gesturing) and persistence of primitive reflexes. They also
found a relation between parental autism traits and infants’
reflex reactions. Specifically, infants who had parents with
higher levels of [subclinical] autistic traits showed more per-
sistent primitive reflexes. However, it is important to note that
this study included infants who did not have any diagnoses.
Therefore, these results might not be applicable to children
later diagnosed with ASD. Caution should also be taken be-
cause, with an upper age limit of 17 months, the researchers
might have identified delays with respect to disappearance of
primitive reflexes rather than longer-term persistence of prim-
itive reflexes. Still, the relation to parental traits suggests that
the persistence or delayed disappearance of primitive reflexes
might serve as an early indicator of some possible familial link
to the autism spectrum.
The overall results of these studies suggest that the snout,
visual rooting, and tonic labyrinthine reflexes might persist in
some children diagnosed with ASD. The presence of such
reflexes could possibly therefore represent an early sign of
ASD. An intriguing finding was the relation between the se-
verity of comorbid intellectual disability and the likelihood of
retaining the visual rooting reflex [44•]. Future research
should examine if any similar such relations might exist be-
tween the persistence of primitive reflexes and the severity of
Other Developmental Disorders
There appear to be relatively few studies into the persistence
of primitive reflexes among individuals with other types of
developmental disorders. Sand, Mellgren, and Hestnes [46•]
reported higher rates of the palmomental (47% of sample) and
snout (14% of sample) reflex in a sample of 30 adults with
Down syndrome, compared to 45 control participants (7 and
0% of the sample, respectively). Bilbilaj, Gjipali, and Shkurti
 reported high retention rates (ranging from 57% to 100%)
for eight different reflexes (asymmetric tonic neck, tonic lat-
eral, symmetrical tonic neck, Galant, Moro, rooting, sucking,
and Palmar) in students with various learning disorders.
However, this study should be interpreted with caution be-
cause the sample was relatively small (n= 14) and included
students with a wide range of conditions (i.e., ASD, ADHD,
dyslexia, and oral disorder). Another study examined primi-
tive reflexes in 67 high-risk infants due to being premature or
needing intensive care . Abnormal reactions to elicitation
of the Moro, Babinski, and sucking reflexes were common,
highlighting the clinical relevance of reflex reactions in iden-
tifying infants at risk for developmental delay/disorder.
Curr Dev Disord Rep
Overall, there is a need for additional research into
the persistence of primitive reflexes among individuals
with, or at risk for, developmental delay/disorder. A
good starting point would be to include participants
representing a range of syndrome conditions and risk
factors. For example, it could be informative to compare
the range and extent to which primitive reflexes are
retained in individuals from different syndrome groups
(e.g., Angelman, fetal alcohol, fragile X, 22q11.2 dele-
tion, and Williams syndrome). Such studies might lead
to the discovery of reflex phenotypes, which could be
useful for early and differential diagnosis.
The results of the studies reviewed in this paper suggest
that primitive reflexes are likely to persist in some in-
dividuals with cerebral palsy, ADHD, ASD, and proba-
bly also in people with a number of other developmen-
tal disorders. Absent, persistent, or atypical reflex reac-
tions might provide a useful indicator of risk for devel-
opmental delay, developmental disorder, learning prob-
lems, and likely functional limitations. Early, regular,
and comprehensive assessments of children’sreflexre-
actions, including assessment of primitive reflexes,
might provide useful diagnostic information and there-
fore should be encouraged.
An important intervention objective would be to minimize
any negative impact on development, learning, and adaptive be-
havior functioning that might arise should primitive reflexes per-
sist past infancy or reappear at some later stage of development.
At least three possible intervention approaches could be
envisioned: (a) preventing elicitation, (b) teaching individuals
to inhibit their own reflex reactions, and/or (c) shaping existing
reflex reactions into the service of a functional (voluntary) re-
sponse. While each of these options has been mooted [2,14,49],
well-controlled intervention studies are lacking and could thus be
seen as a priority area for future research.
Acknowledgement Appreciation is extended toPeterB. Marschik for his
helpful comments on previous drafts of this paper.
The authors have complied with the relevant ethical standards of their
Conflict of Interest The authors declare no competing interests.
Human and Animal Rights and Informed Consent This article does not
contain any studies with human or animal subjects performed by
any of the authors.
Papers of particular interest, published recently, have been
•• Of major importance
1. Mercuri E, Ricci D, Pane M, Baranello G. The neurological exam-
ination of the newborn baby. Early Hum Dev. 2005;81:947–56.
2. Chandradasa M, Rathnayake L. Retained primitive reflexes in chil-
dren, clinical implications and targeted home-based interventions.
Nurs Child Young People. 2019;32:37–42.
3. Futagi Y, Toribe Y, Suzuki Y. Neurological assessment of early
infants. Curr Pediatr Rev. 2009;5:65–70.k.
4. Jakobi J, Kohn S, Kuzyk S, Fedorov A. When kicking the doctor is
good: a simple reflex. Front Young Minds. 2017;5:10. https://doi.
5. Hamer EG, Dijkstra LJ, Hooijsma SJ, Zijdewind I, Hadders-Algra
M. Knee jerk responses in infants at high risk for cerebral palsy: an
observational EMG study. Pediatr Res. 2016;80:363–70.
6. Fetcho JR, McLean DL. Startle response. In: Squire LR, editor.
Encyclopedia of neuroscience. Cambridge: Academic press;
2009. p. 375–9.
7. Valls-Sole J. Spontaneous, voluntary, and reflex blinking in clinical
practice. J Clin Neurophysiol. 2019;36:415–21.
8. Leder SB. Gag reflex and dysphagia. Head Neck. 1996;18:138–41.
9. Boes CJ. The history of examination of reflexes. J Neurol.
10. Gieysztor EZ, Choinska AM, Paprocka-Borowicz M. Persistence
of primitive reflexes and associated motor problems in healthy pre-
school children. Arch Med Sci. 2018;14:167–73.
11. Grzywniak C. Role of early-childhood reflexes in the psychomotor
development of a child, and in learning. Acta Neuropsychol.
12. Paulson G, Gottlieb G. Developmental reflexes: the reappearance of
foetal and neonatal reflexes on aged patients. Brain. 1968;91:37–
13. Modrell AK, Tadi P. Primitive reflexes. In: StatPearls. Treasure
Island: StatPearls Publishing; 2020. https://europepmc.org/article/
med/32119493#impact. Accessed 11 Nov 2020.
14. Rousseau PV, Matton F,Lecuyer R, Lahaye W. The Moro reaction:
more than a reflex, a ritualized behavior of nonverbal communica-
tion. Infant Behav Dev. 2017;46:169–77.
15. Chinello A, Di Gangi V, Valenza E. Persistent primary reflexes
affect motor acts: potential implications for autism spectrum disor-
der. Res Dev Disabil. 2018;83:287–95.
16. Jacobs L, Gossman MD. Three primitive reflexes in normal adults.
17. Gulati S, Sondhi V. Cerebral palsy: an overview. Indian J Pediatr.
18.•• Capute AJ. Identifying cerebral palsy in infancy through study of
primitive-reflex profiles. Pediatr Ann. 1979;8:34–42 This
pioneering study established the utility of a standardized pro-
tocol (primitive reflex profile) for assessing the persistence of
primitive reflexes in children with cerebral palsy.
19.•Capute AJ, Accardo PJ, Vining EPG, Rubenstein JE, Walcher JR,
Harryman S, et al. Primitive reflex profile: a pilot study. Phys Ther.
1978;58:1061–5Large-scale study that further established the
clinical utility of the primitive reflex profile.
20.•Dos Santos MTBR, Nogueira MLG. Infantile reflexes and their ef-
fects on the dental caries and oral hygiene in cerebral palsy individ-
uals. J Oral Rehabil. 2005;32:880–5Showed that the biting reflex
was persistent in children with cerebral palsy and interfered
with oral hygiene.
Curr Dev Disord Rep
21.•• Smith SL, Gossman MR, Canan BC. Selected primitive reflexes in
children with cerebral palsy: consistency of response. Phys Ther.
1982;62:1115–20 Showed that the extent to which primitive re-
flexes could be elicited varied in relation to the child’slevelof
alertness. The results have implications for the timing of
conducting reflex assessments.
22.•• Zafeiriou DI, Tsikoulas IG, Kremenopoulos GM. Prospective
follow-up of primitive reflex profiles in high-risk infants: clues to
an early diagnosis of cerebral palsy. Pediatr Neurol. 1995;13:148–
52 Large-scale study showed that retention of primitive reflexes
was a useful diagnostic tool for cerebral palsy.
23. Arthur-Kelly M, Foreman P, Maes B, Colyvas K, Lyons G.
Observational data on socio-communicative phenomena in class-
rooms supporting students with profound intellectual and multiple
disability (PIMD): advancing theory development on learning and
engagement through data analysis. Adv Neurodev disord. 2018;2:
24. Sama AA. Attention-deficit hyperactivity disorder (ADHD) in chil-
dren: a move towards developmental perspectives. Int J Res Anal
25. American Psychiatric Association. Diagnostic and statistical man-
ual of mental disorders (5
ed., DSM-5). Arlington, VA: American
Psychiatric Association; 2013.
26.•• Taylor M, Houghton S, Chapman E. Primitive reflexes and atten-
tion-deficit/hyperactivity disorder: developmental origins of class-
room dysfunction. Int J Spec Educ. 2004;19:23–37 Demonstrated
that children with ADHD were more likely to retain four types
of primitive reflexes compared to typically developing children
and that persistence of these reflexes was related to lower aca-
demic achievement in the area of mathematics.
27.•Konicarova J, Bob P. Retained primitive reflexes and ADHD in
children. Activitas Nervosa Superior. 2012;54:135–8First in a se-
ries of papers by this team showing a high prevalence of persis-
tent primitive reflexes in children with ADHD.
28. Loyer Carbonneau M, Demers M, Bigras M, Guay M-C. Meta-
analysis of sex differences in ADHD symptoms and associated
cognitive deficits. J Atten Disord. 2020:108705472092373.
29. Konicarova J, Bob P. Asymmetrical tonic neck reflex and symp-
toms of attention deficit and hyperactivity disorder in children. Int J
30. Conners CK. Parent symptom questionnaire. Psychopharmacol
31. Konicarova J, Bob P, Raboch J. Persisting primitive reflexes in
medication-naïve girls with attention-deficit and hyperactivity dis-
order. Neuropsychiatr Dis Treat. 2013;9:1457–61.
32. Melillo R. Primitive reflexes and their relationship to delayed cor-
tical maturation, under connectivity and functional disconnection in
childhood neurobehavioral disorders. Funct Neurol Rehabil Ergon.
33. Konicarova J, Bob P. Principle of dissolution and primitive reflexes
in ADHD. Activitas Nervosa Superior. 2013;55:74–8.
34. Paulson G, Gottlieb G. Development reflexes: the reappearance of
foetal and neonatal reflexes in aged patients. Brain. 1986;92:37–52.
35. Vreeling FW, Houx PJ, Jolles J, Verhey FRJ. Primitive reflexes in
Alzheimer’s disease and vascular dementia. J Geriatr Psychiatry
36. Hogan DB, Ebly EM. Primitive reflexes and dementia: results from
the Canadian study of health and aging. Age Ageing.1995;24:375–
37. Hodges H, Fealko C, Soares N. Autism spectrum disorder: defini-
tion, epidemiology, causes, and clinical evaluation. Transl Pediatr.
38. Damiano CR, Mazefsky CA, White SW, Dichter GS. Future direc-
tions for research in autism spectrum disorders. J Clin Child
Adolesc Psychol. 2014;43:828–43.
39. Anderson GM. The potential role for emergence in autism. Autism
40. Happé F, Firth U. The neuropsychology of autism. Brain.
41. Schultz S, Kiln A, Jones W. Neonatal transitions in social behavior
and their implications for autism. Trends Cogn Sci. 2018;22:452–
42. Torres EB, Brincker M, Isenhower RW, Yanovich P, Stigler KA,
Nurnberger JI, et al. Autism: the micro-movement perspective.
Front Integr Neurosci. 2013;7(32):1–26.
43.•• Minderaa RB, Volkmar FR, Hansen CR, Harcherik DF, Akkerhuis
GW, Cohen DJ. Brief report: Snout and visual rooting reflexes in
infantile autism. J Autism Dev Disord. 1985;15:409–16 Classic
early study showing extremely high rates of retention of the
snout and visual rooting reflexes in children with autism.
44.•de Bildt A, Mulder EJ, Van Lang NDJ, de With SAJ, Minderaa RB,
Stahl SS, et al. The visual rooting reflex in individuals with autism
spectrum disorders and co-occurring intellectual disability. Autism
Res. 2012;5:67–72 Showed a relation between the level of comor-
bid intellectual disability and likelihood of retaining the visual
rooting reflex in a large sample of individuals with autism.
45.•Accardo PJ, Barrow W. Toe walking in autism: further observations.
J Child Neurol. 2015;30:606–9The tonic labyrinthine reflex was
common and associated with toe walking in a sample of 61 chil-
dren with autism suggesting that retention of this reflex nega-
tively affected ambulation.
46.•Sand T, Mellgren SI, Hestnes A. Primitive reflexes in Down’ssyn-
drome. J Ment Defic Res. 1983;27:39–44 One of the few studies to
examine primitive reflexes in adults, specifically adults with
Down syndrome. They reported persistence of the palmomental
and snout reflex compared to typical controls.
47. Bilbilaj S, Gjipali A, Shkurti F. Measuring primitive reflexes in
children with learning disorders. Eur J Multidisciplinary Stud.
48. Sohn M, Ahn Y, Lee S. Assessment of primitive reflexes in high-
risk newborns. J Clin Med Res. 2011;3:285–90.
49. Sigafoos J, Roche L, Tait K. Challenges in providing AAC inter-
vention to people with profound intellectual and multiple disabil-
ities. In: Ogletree BT, editor. Augmentative and alternative com-
munication challenges and solutions: improving everyday service
delivery (pp: 229–252) Pural Publishing; 2021.
Publisher’sNote Springer Nature remains neutral with regard to jurisdic-
tional claims in published maps and institutional affiliations.
Curr Dev Disord Rep
Terms and Conditions
Springer Nature journal content, brought to you courtesy of Springer Nature Customer Service Center GmbH (“Springer Nature”).
Springer Nature supports a reasonable amount of sharing of research papers by authors, subscribers and authorised users (“Users”), for small-
scale personal, non-commercial use provided that all copyright, trade and service marks and other proprietary notices are maintained. By
purposes, Springer Nature considers academic use (by researchers and students) to be non-commercial.
These Terms are supplementary and will apply in addition to any applicable website terms and conditions, a relevant site licence or a personal
subscription. These Terms will prevail over any conflict or ambiguity with regards to the relevant terms, a site licence or a personal subscription
(to the extent of the conflict or ambiguity only). For Creative Commons-licensed articles, the terms of the Creative Commons license used will
We collect and use personal data to provide access to the Springer Nature journal content. We may also use these personal data internally within
ResearchGate and Springer Nature and as agreed share it, in an anonymised way, for purposes of tracking, analysis and reporting. We will not
otherwise disclose your personal data outside the ResearchGate or the Springer Nature group of companies unless we have your permission as
While Users may use the Springer Nature journal content for small scale, personal non-commercial use, it is important to note that Users may
use such content for the purpose of providing other users with access on a regular or large scale basis or as a means to circumvent access
use such content where to do so would be considered a criminal or statutory offence in any jurisdiction, or gives rise to civil liability, or is
falsely or misleadingly imply or suggest endorsement, approval , sponsorship, or association unless explicitly agreed to by Springer Nature in
use bots or other automated methods to access the content or redirect messages
override any security feature or exclusionary protocol; or
share the content in order to create substitute for Springer Nature products or services or a systematic database of Springer Nature journal
In line with the restriction against commercial use, Springer Nature does not permit the creation of a product or service that creates revenue,
royalties, rent or income from our content or its inclusion as part of a paid for service or for other commercial gain. Springer Nature journal
content cannot be used for inter-library loans and librarians may not upload Springer Nature journal content on a large scale into their, or any
other, institutional repository.
content on this website and may remove it or features or functionality at our sole discretion, at any time with or without notice. Springer Nature
may revoke this licence to you at any time and remove access to any copies of the Springer Nature journal content which have been saved.
To the fullest extent permitted by law, Springer Nature makes no warranties, representations or guarantees to Users, either express or implied
with respect to the Springer nature journal content and all parties disclaim and waive any implied warranties or warranties imposed by law,
including merchantability or fitness for any particular purpose.
Please note that these rights do not automatically extend to content, data or other material published by Springer Nature that may be licensed
from third parties.
If you would like to use or distribute our Springer Nature journal content to a wider audience or on a regular basis or in any other manner not
expressly permitted by these Terms, please contact Springer Nature at