Baby Raises and Lowers Both Legs in Sleep
Proc Natl Acad Sci U S A. 1998 November 10; 95(23): 13982–13987.
Psychology
Movement analysis in infancy may be useful for early diagnosis of autism
Philip Teitelbaum
Departments of *Psychology and ‡Child Psychiatry, University of Florida, Gainesville, FL 32611
Osnat Teitelbaum
Departments of *Psychology and ‡Child Psychiatry, University of Florida, Gainesville, FL 32611
Jennifer Nye
Departments of *Psychology and ‡Child Psychiatry, University of Florida, Gainesville, FL 32611
Joshua Fryman
Departments of *Psychology and ‡Child Psychiatry, University of Florida, Gainesville, FL 32611
Ralph Thousand. Maurer
Departments of *Psychology and ‡Child Psychiatry, Academy of Florida, Gainesville, FL 32611
Abstruse
All of the 17 autistic children studied in the present paper showed disturbances of movement that with our methods could be detected conspicuously at the age of iv–6 months, and sometimes even at birth. Nosotros used the Eshkol–Wachman Motion Analysis Organisation in combination with still-frame videodisc analysis to study videos obtained from parents of children who had been diagnosed as autistic by conventional methods, usually effectually 3 years old. The videos showed their behaviors when they were infants, long earlier they had been diagnosed every bit autistic. The motility disorders varied from child to kid. Disturbances were revealed in the shape of the mouth and in some or all of the milestones of development, including, lying, righting, sitting, crawling, and walking. Our findings support the view that motility disturbances play an intrinsic part in the phenomenon of autism, that they are present at birth, and that they tin be used to diagnose the presence of autism in the first few months of life. They indicate the demand for the evolution of methods of therapy to be applied from the first few months of life in autism.
There is controversy over whether movement disorders play a central part in the miracle of autism and even whether such movement disorders be in autism at all. For instance, Rimland (1) has stated:
It has been widely recognized for many decades that the vast bulk of autistic persons are quite unimpaired with regard to their finger dexterity and gross motor capabilities. They have in fact often been described as specially dexterous and coordinated. The literature abounds with stories of young autistic children who can take apart and reassemble pocket-size mechanical devices, build towers of blocks and dominos higher than a normal adult can, assemble jigsaw puzzles and climb to dangerously high places without falling… The idea that autism is, or typically involves, a "movement disorder" is simply ludicrous … .
On the other hand, Damasio and Maurer (2) and Vilensky et al. (three) showed that autistic children between the ages of 3 and 10 walk somewhat similar Parkinsonian adults in that they walk more slowly than normal, with shorter steps. Correspondingly, Courchesne et al. (iv), using MRI, have shown that certain areas of the cerebellar vermis are incompletely adult in autistic children [merely meet Piven (five)]. This as well supports the view that movement disorders might play a role in autism (6, seven).
We believe that the findings presented here help to resolve this controversy. We used Eshkol–Wachman Movement Analysis in combination with flicker-gratuitous laser-disc withal-frame analysis to study videos taken in infancy of 17 children who later turned out to be autistic, as diagnosed at the historic period of 3 years or older by conventional methods of diagnosis. Every one of these children displayed movement disorders, some subtle, some obvious.
Furthermore, because these move disorders always could be detected with our methods as early as 4–6 months of age and sometimes as early as the first few days after nativity, nosotros advise that the study of movement disorders in infancy may serve equally an earlier indicator than presently available methods for diagnosing autism in children.
Equally a framework for the report of baby movement, nosotros decided to analyze the movements involved in the major motor milestones in the evolution of the babe from nascence through the time that he or she starts to walk: i.e., lying, righting, sitting, crawling, continuing, and walking. Every child goes through these stages (infants with severe neurological defects who are unable to progress through these stages of development are not included in the nowadays word). Therefore, these motor milestones tin can serve as a common denominator by which to evaluate and compare normal and disintegrated movement in infants.
METHODS
We advertised in the monthly periodical published past the National Committee on Autism and in the electronic mail list run past the Autism Society of America. We asked parents of autistic children (diagnosed by conventional methods usually at 3 years or older) to send us videos of their children taken when they were infants. We received and copied videos of 17 such infants and compared their patterns of lying (prone and supine), righting from their back to their stomach, sitting, itch, standing, and walking with that of xv normal infants. The normal infants were filmed by us in the nurseries of Kibbutz Merhavia in Israel when each pattern was only beginning to develop. Selected portions of these behaviors were transferred to videodisc (Panasonic Rewritable Optical Disc Recorder LQ-4000, Secaucus, NJ) for still-frame analysis by using Eshkol–Wachman Motion Annotation (8). Eshkol–Wachman Move Notation is a general assay system in which spherical coordinates are applied independently to each segment of the body. By distinguishing between which segments are actively moving versus those that are beingness carried passively along, a deeper understanding of abnormal movement is possible.
RESULTS
Motor Milestones in Evolution
Lying.
Lying is an active posture, even in the first few days of life. As has been pointed out past Casaer (9), a newborn baby maintains specific active postures while lying. Persistent deviations from the normal patterns of lying tin can indicate abnormalities associated with autism. For example, one of the children in the nowadays report showed a persistent asymmetry§ at the age of iv months when lying on his stomach. His right arm always was defenseless nether his chest, and fifty-fifty when engaged in reaching for an object with the other arm, he notwithstanding did not employ his correct arm. Throughout his first twelvemonth, this disproportion persisted, causing the child to fall to his right side when lying on his tum, or when sitting, and fifty-fifty when he started to walk.
Righting from Supine to Prone.
Rolling over from back to stomach usually begins around 3 months of historic period. It involves a rotation around the longitudinal axis of the trunk (see Fig. xi), in a corkscrew fashion, one body segment afterward the next. Typically, in the earliest form of such righting, the pelvis turns start, then the trunk, and finally the shoulders and head. By 6 months of age, cephalic authorization is evident (x, 11), and this gild is reversed. The head turns get-go, and the shoulders, trunk, and pelvis follow (Fig. 1).
A normal infant, ≈6 months old, shows cephalic potency in the initiation of righting to prone when lying supine on the ground. The head turns first, and the shoulders, torso, and pelvis follow sequentially until the child reaches the prone position.
A definition of the three types of motility that can be performed past the body. (Plane motion) The limb segment moves in a airplane that is at 90 degrees to the axis of its motion. (Rotatory movement) The limb moves at an angle of cypher degrees to its ain axis: i.eastward., it does not move in infinite, merely only twists around the axis through its length. (Conical motility) The limb moves at an bending <90 degrees and >0 degrees to its axis of movement.
In our experience, impairments in righting exist in autistic infants. Some cannot plough over at all. Others, although managing to plough over, and thus "getting the job washed," practice information technology in the post-obit manner: starting from lying on their side (rather than on their dorsum as normal children would practice), they curvation themselves sideways by raising the head and pelvis upward (Fig. 2). This narrows the base of operations of the body then that past moving the upper leg forrad that leg can serve as a weight to topple the body over. All of the segments of the body move en bloc, not in a corkscrew fashion. This results in the child falling over, without any active rotation.
An autistic infant, ≈five months old, cannot right by rotation. Instead, he arches the head and pelvis sideways upward, moves the top leg forwards, and topples over en bloc, without the sequential segmental rotation in the righting movement characteristic of normal children.
It must be noted that, even though we have videos of 17 autistic children and so far, only a few of these home videos actually filmed righting on the ground in such children. Thus, nosotros have just a very limited sample (north = 3) of the righting behavior of autistic infants. However, the sideways–upwards design of righting seen in all three of these autistic children is quite different from what normal children ever show when righting on the ground. The abnormal pattern of righting that we accept just described was seen by us when the autistic children ranged in age from 6 to 9 months one-time. One of these children, at the historic period of 3 months, when lying supine, flexed his caput and neck strongly forward in the midline (run into Fig. 3 a and b). Such midline frontward flexion can exist seen in the normal newborn at the age of five days (nine), but it is atypical for information technology to appear at 3 months of age. In other words, the forrad-flexion pattern shown by the autistic child may be a more infantile pattern.
An autistic child, ≈3 months sometime, lacking the ability to rotate around the body midline during righting (a), attempts to sit down up by ventroflexing his body in the midline plane (b).
Sitting.
Usually, at ≈vi months of age, a normal baby can sit upright. He maintains his equilibrium by distributing his trunk weight every bit on his sitting bones, even when, past reaching for a toy, his upper torso will be out of the vertical. Turning his head, rocking in identify, or busying his easily with objects, he maintains his stability.
Some autistic children were not able to maintain sitting stability at this age. In the extreme, he or she only fell over like a log, without using whatsoever allied reflexes to protect himself (meet Fig. iv). In other cases, where there was less astringent movement disturbance, the baby managed to sit for a few minutes at a time, but, considering his weight often was not distributed equally on both sides, his posture was asymmetrical, leaning to one side, and he roughshod over when reaching for objects or moving his arms and upper body.
An autistic girl, eight.5 months old, shows no centrolineal protective reflexes when falling (e.g., extending the arms and hands out to protect herself from hit her head when falling toward the footing).
Crawling on Hands and Knees.
Almost babies start to clamber at about the same time they begin to sit. In that location are several forms of creeping and crawling and there is much debate about the interlimb patterning involved (encounter ref. 12 for a detailed discussion of this topic). Nosotros will consider hither only crawling on hands and knees. The following will be used as a reference starting position: arms vertical at shoulder width, palms on the floor fingers pointing forrard; thighs vertical and hip-width apart, knees on the basis with lower legs and feet resting on the floor pointing backwards; and weight every bit distributed on all four limbs (see Fig. v). Notation that this is an "ideal" position: a infant who is playing and moving effectually rarely will stop in this position, but information technology can serve as a reference relative to which other movement patterns—normal and abnormal—tin can be studied. When crawling forrad on easily and knees, the arms and thighs move parallel to the midline axis of the torso. That means that the arms stay shoulder-width apart, and so do the thighs.
A normal baby, ≈6 months old, shows good support in the arms and legs while crawling forward.
Autistic Children May Show Deviations from the Normal Pattern of Crawling.
Asymmetrical lack of acceptable support in the arms. As shown in Fig. 6, this infant did not take adequate support in his arms, and so that he supported himself on his forearms rather than his hands. Note that i arm is crossed in front of the other and then that his base of back up on his arms is very narrow. Although support was deficient in both artillery, the correct arm was weaker than the left, so that reaching was done with the left arm while the right arm often was defenseless nether the body. He appeared to intend to crawl forward to reach the pocket-size roller on the floor in forepart of him. Because he could non move his thighs toward his tummy, and thus was not able to "stride" forwards on his knees and shift his weight, he was stuck in identify. The effect was that he raised his pelvis into the air while leaning on his upper arms, his body in an upside down Five shape. He tried a few times to move forrard past bringing his knees to the ground and pushing himself, only over again and again, instead of moving forward, his knees came off the floor, extending his legs and bringing his bottom up.
An autistic baby, ≈v months old, is unable to support himself on his hands and is unable to bring his knees toward his chest to clamber frontward, and so he lifts his rump up while trying to crawl but cannot move forward from the spot.
Disproportion in the legs.
(i) In the adjacent video taken of the kid described in a higher place, at the historic period of half dozen months, the arms had developed back up, and the legs now could be used in itch. However, a rest correct-sided deficiency remained in the use of his legs in itch: from the starting position described above, the left leg moved the usual style (thigh moves forward under the belly, lower leg and foot sliding on the floor) whereas the correct thigh did non move actively. It was carried passively past a sideways flexion of the right hip (so that the hip came closer to the rib muzzle). This motion of the hip carried the thigh medially likewise as forward, and so that, with each crawling stride, the base of the body progressively was narrowed, resulting in eventual falling over to the right.
(2) Some other autistic child is shown in Fig. 7. When this baby crawled, the left leg moved the usual way (the left thigh moved forward under the abdomen with the lower leg and foot sliding on the flooring, and the left knee joint contacted the ground at the end of each footstep) whereas the right leg stepped forward by using the foot (the lower leg is vertical with just the pes contacting the ground at the end of each step).
An autistic baby shows asymmetry in his crawling: the left leg crawls properly, only the right foot steps rather than crawls.
Standing.
A normal baby, ≈viii–10 months one-time, may pull himself upwards and represent a few minutes, sometimes leaning against a slice of heavy article of furniture. After a short menstruation of time, though, he typically volition subside to the floor to continue his activities. Ane autistic daughter of that age seen in Fig. 8 stood in one place leaning her back confronting a heavy piece of furniture for periods as long as 15 minutes at a fourth dimension. Such relative akinesia may signal abnormality.
Moebius Syndrome shape of the mouth in an eight.v-month-former autistic girl. The lower lip is flat, but the upper lip is biconvex in a characteristic shape.
Walking.
When a babe starts to walk, his gait develops through fixed stages that comprise a proximal–distal gradient that governs the command of the different segments of the legs. The thigh, the segment of the leg most proximal to the body, is the only segment that actively moves at first. The lower leg and the foot simply are carried passively along by the move of the thigh. They practise non move actively. Later, they add their activity successively. This paradigm of normal walking enables united states to analyze deviations from it.
When a baby starts to walk, 3 stages tin can be differentiated. (i) Waddling: From a starting position of stability (run across Fig. 9), in which the baby stands all the same, both legs parallel and weight equally distributed, the body weight is shifted laterally to 1 leg. This enables the other leg to lift and step forward. Because only the thigh moves actively (equally in crawling, the lower leg and foot are being carried passively forth), the pace is very short. The foot is planted as a whole, neither toes nor heel touching the flooring beginning. The baby then shifts his weight sideways to the leg that has just stepped, releases the other leg and brings it in a "take hold of-up" step to a position parallel to the leg that simply had stepped. The issue is a "waddling walk" in which, although the babe progresses forrard, he does it by waddling from side to side, with long intervals of standing still between each pair of steps. (This can be noticed virtually conspicuously past watching the caput.) The hands are raised shoulder loftier, forearms vertical (See Fig. 9).
A normal infant, ≈10 months quondam, holds his arms upwards at shoulder level as he is just outset to acquire to walk.
(2) Intermediate stage: Start the step-gesture, then the shift of weight; the catch-upwardly step is transformed into a full pace forward and the pace cycle develops every bit follows. The trunk weight shifts, allowing the babe to release the rear pes from the basis by rolling it from heel to toe, which, in turn, flexes the lower leg relative to the thigh. When, from this position, the lower leg swings forward, carried past the movement of the thigh, the whole leg is lowered back to the footing, the human foot landing apartment ahead of the other pes. Only after the leading foot has been placed on the floor is the torso weight shifted forward (rather than from side-to-side as in stage i). The arms are lowered then that the upper arms hang down along the sides of the trunk, and the lower arms are held waist-high, parallel to the ground, pointing forward. It should exist noted that, in adults with Parkinson's illness, there is a stage of deterioration of the step cycle that parallels the form of stepping shown in this intermediate phase of the normal development of walking. Only after the leading human foot is on the footing does the body weight shift forrard (thirteen).
(iii) Final stage: The body weight is superimposed on the step gesture; although in stages i and ii, the shift in trunk weight was delayed until both feet were on the footing, in this stage, weight shift occurs simultaneously with the stepping movement of the leading leg (while the leading leg is in the air). The leading human foot then touches the floor heel offset, and, as the balance of the foot rolls onto the floor, it acts to wheel the trunk weight smoothly forrad. The rear heel lifts from the ground before the forepart human foot touches the footing, enabling ane to see that the weight is existence shifted. The whole cycle is permitted by and permits the continuous shift of weight forward. The rolling of the foot determines the flexing of the lower leg, which and so swings forward and extends to bring the heel of the flexed pes in touch on with the floor. The arms are downward forth the sides of the body, non coordinated yet with the pace cycle.
These 3 stages in the development of the footstep can be observed in every baby that starts to walk. Yet, the duration of each stage may vary greatly, lasting anywhere from a few days to several weeks. Also, the control of the arms may develop at different rates from that of the legs. For case, the arms may exist in an advanced stage (downwards alongside the body), and the legs may be in stage i or ii, and vice versa.
In the gait of autistic children, the deviations from the normal can be categorized equally follows. (i) Asymmetry: In normal walking, the movements involving the arms and legs are symmetrical. In every autistic child we have seen so far, some degree of asymmetry has been plant. For case, when walking, a 10-year-onetime girl held the right arm in a more infantile position (lower arm held at waist pinnacle, as described to a higher place) while the left arm was held downward every bit it swung alongside the body. When walking, a three-year-old boy exhibited an infantile blueprint in the correct leg, where only the thigh was moving, carrying the lower leg and the foot with information technology. The other leg showed a more mature pattern; that is, all parts of the leg moved relative to ane another, the heel of the foot being placed on the ground first.
(2) Delayed development: At the age of 2 or even later on, the gait may exist more infantile than normal. Thus, one autistic child at the age of 2 exhibited active move of each thigh merely, with the lower leg and foot existence carried passively. As well, the foot was planted on the floor as a whole, and there was no release of the hind heel and thus no smooth transfer of weight.
(iii) Sequencing, non superimposition: At the age of v, as shown in Fig. 10, this autistic child exhibited all of the components of a "mature" step; that is, the thigh and lower leg and foot moved actively forward, but this was done without the shift of weight that ordinarily goes with it. Only after the leg was extended fully in the air did the shift of weight occur, so that the kid fell forward on to it in a "goose step" form of walking. The shift of body weight occurred after, non along with, the motility of the leg.
(a) A 5-year-one-time autistic boy has a fully developed step gesture. All three segments of the leg motility actively (see text), just his body weight does non shift at the same time, resulting in a course of goose-footstep. (b) The trunk weight merely then is shifted then that the boy falls on to the outstretched leg at each footstep. This is a course of sequencing rather than superimposition of one movement on the other.
(iv) The arms: In our experience, every bit a full general dominion, papers written virtually walking deal only with the action of the legs, omitting any discussion of the part of the artillery in walking. This is unfortunate, because the action of the arms is extremely important in facilitating the gait via allied reflexes. In earlier work (13), it was shown that patients with Parkinson's disease can greatly augment the size and speed of their steps by increasing the aamplitude of their arm swing. Furthermore, as described above, there are specific positions of the arms that accompany the stages of evolution of walking. These arm positions tin can serve every bit milestones forth the course of normal development. If, in the grade of development, there is arrest in an early on stage (as signaled by the position of the arms), this tin indicate abnormality. For example, in the study carried out by Vilensky, Damasio, and Maurer (iii), several autistic children (ages 3–x) exhibited more infantile positions of the arms while walking: the forearm often was held parallel to the ground, pointing forrad. In several cases, the arms were not held in a symmetrical position: ane arm was in a more than mature position (the arm fully extended downwards alongside the body) while the other was in a more infantile position (forearm held horizontal, pointing frontward).
(v) Arm-and-hand flapping: Arm-and-mitt flapping often can exist seen in autistic children. Information technology also can appear in normal children, usually for a few months, before it disappears. For this reason, it is difficult to use as a sign diagnostic of autism. However, if it persists to an age at which the mature form of walking should be well adult (2 years old or more), then other confirming signs should be looked for as well.
In some of the children studied here, we observed a characteristic mouth shape (run into Fig. 8) chosen "Moebius Syndrome" (14). This rima oris shape can be seen in the first few days afterward nascence and may persist throughout infancy and on into adulthood. It does non occur in all infants who turn out to be autistic, but, when information technology does occur, it signals the need to notice closely the movements displayed by the infant. If some of the other symptoms of movement disorder that we have described hither also occur, it strengthens the possibility that autism is involved.
DISCUSSION
Autism generally is diagnosed at ≈iii years of age, when a child begins to participate in organized social settings (in a plant nursery school, for instance). Because social skills required are aberrant in such a child, it is relatively easy to spot autistic behavior at that place. Such a kid may non participate in social play with other children, stays by himself, and does non want to be touched by anyone. He refrains from centre contact, has difficulty expressing himself verbally, and sometimes does non talk at all. Indeed, Osterling and Dawson (15) were able to describe the deviant behaviors of autistic children by analyzing their social beliefs from videos taken at their get-go birthday party. The trouble is that, in infancy (4–6 months), the social symptoms are not and so readily apparent. The infant in his crib relates largely to himself, and just his movements reverberate the activity of his nervous system. The kid's mother is normally aware very early that something is wrong, but, because she is unable to specify something diagnostic, the pediatrician she consults ofttimes tends to reassure her that this is a minor problem that the child volition grow out of. Hashimoto et al. (16), using developmental delay, poor facial expression, and failure to make eye contact as indicators, were able to screen for autism at vi months. Because it has been shown that virtually all autistic children at subsequently ages have movement abnormalities (2, 3), we reasoned that such abnormalities might exist axiomatic in the beginning few months of life. Equally shown in the present paper, this is indeed and so.
It is important that the abnormalities in movement that we have described here tin can exist seen very early in infancy, long before the behaviors in social settings that currently form the basis for the diagnosis of autism. Diagnosis in infancy tin can bespeak the need for therapeutic behavioral interventions that might provide greater degrees of recovery from autism. Temple Grandin (17) is a famous instance of the remarkable degree of spontaneous recovery that is possible in autism. It is axiomatic that the before the therapy, the more constructive it volition exist. Therefore, the fact that abnormalities in movement can be very early indicators of potential autism is important to know.
It also should be noted that the movement disturbances that nosotros have found in autistic children typically occurred on the right side of the body. This is in contrast to the movement disturbances reported in schizophrenic children in infancy, where they occur typically on the left side of the body (xviii). A more detailed comparison of the movement disorders found in autistic infants with those found in schizophrenic infants would exist very valuable.
The present findings are also important for pediatricians. Fourth dimension and time again, in our correspondence with the mothers of autistic children, we have heard that the mother suspected that something was wrong with her baby but that the pediatrician told her that everything was all right and that she need not worry. The pediatrician should exist the primeval, not the last, to know that the child might exist autistic. An awareness that simple movements such as those described in the present paper might help in the diagnosis of potential autism would exist valuable for pediatricians.
The fact that such early diagnosis is possible now highlights the need for the development of earlier therapies that will be constructive in the handling of potentially autistic children. Because diagnosis was not by and large possible then early, no systematic methods are currently available for the treatment of infants at risk for autism. Our findings should provide the impetus for systematic search for such treatment methods.
How practice nosotros reconcile our findings of deficits in the evolution of move in autistic infants with the reports from parents cited by Rimland (ane) indicating that many autistic children brandish hyperagility and hyperdexterity? Two possibilities be. Kickoff, information technology is possible that, in our limited sample of autistics, we have non accomplished an adequate sample and that there exists a subgroup of autistics that display such hyperagility and dexterity even in infancy. Because we obtained our videos without request for any special characteristics other than a diagnosis of autism, we accept no reason to assume that there was a systematic bias in our sample. Alternatively, information technology is possible that a transformation occurs in development in autistic children, so that many of the children whose videos showed movement abnormalities in infancy might at a subsequently age evidence hyperagility and dexterity, akin to that reported past Rimland (i). This merits further investigation.
Finally, in infancy, the motility disorders nowadays in autism are clearest, non yet masked past other mechanisms that take developed to recoup for them. It is possible that they may vary according to the areas of the brain in which developmental delay or impairment has occurred. For instance, Kemper and Bauman (6) have pointed out from anatomical analysis of the brains of autistic individuals that the limbic system besides as the cerebellum may evidence small shrunken cells. Courchesne (4) has prove from MRI analysis that the cerebellum may show hypoplasia or even hyperplasia in certain regions of the cerebellum. By combining movement analysis in infancy with MRI analysis, information technology may be possible somewhen to diagnose differential areas of brain involvement in unlike subtypes of autism.
Note. Unfortunately, we did non accept electronic versions of the figures used in this paper. We attempted to increase the clarity of the figures (which were taken straight from dwelling videos) with numerous methods, but, considering of the nature of the original images, we had piffling success.
Acknowledgments
We are grateful to the families who sent us the videotape material that we have analyzed in this paper. Their goodwill and cooperation made this work possible.
Footnotes
§Asymmetry can be seen briefly in many normal babies. However, if such asymmetry is persistent, a closer exam would exist worthwhile.
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Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC25000/
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