Early Warning Signs of Autism

Baby smiling

Identifying autism spectrum disorders (ASDs) at the earliest age possible is of the utmost importance because early treatment can be very beneficial to the child and his/her family.

Abnormalities in how babies acts socially, as well as how they pay attention to and interact with their non-social environment, may be early warning signs.  A delay in speech alone generally does not signify autism, but in combination with other warning signs, could suggest that a toddler is at risk.  

Below are early warning signs describing what children at risk for an ASD between 12-24 months generally don¹t do, as well as a description of what they might do. Note that it is very common for typically developing toddlers to also show some of the red flags listed below. 

Only a professional can determine if your infant/toddler is at true risk for an autism spectrum disorder. If you are concerned and your baby is between 12-36 months and you live in the San Diego area, please contact our ACE Center at 858-534-6912 for an evaluation.

Toddlers between 12-24 months at risk for
an Autism Spectrum Disorder MIGHT:

Talk or babble in a voice with an unusual tone

When a child at-risk for autism vocalizes, the voice might not vary in pitch, tone, or volume. The vocalizations of children who are not yet speaking might sound more like non-word sounds (e.g., whining, fussing, growling) than like parts of words.

  • Example of a typically developing child: Mrs. Smith hears her son, Johnny, babbling in his crib and notices that it sounds like he is conversing in a foreign language.
  • Example of a child at risk for autism: Mrs. Jones hears her son, Sam, vocalizing in his crib. Rather than babbling, she hears what sounds like monotone humming and, at times, even whining.

Scientific References:

  • Sheinkopf, Mundy, Oller, & Steffens (2000). Vocal atypicalities of preverbal autistic children. Journal of Autism and Developmental Disorders. 30(4):345-354.
  • Wetherby, Woods, Allen, Cleary, Dickinson, & Lord (2004). Early indicators of autism spectrum disorders in the second year of life. 34(5):473-493.

Display unusual sensory sensitivities

A child at risk for autism might show unexpected reactions to certain sounds, textures, and/or tastes.

  • Example of a typically developing child: When feeding 18 month-old Johnny lunch, Mrs. Smith notices that he eats a variety of foods but, as usual, refuses to eat his vegetables.
  • Example of a child at-risk for autism: When feeding 18 month-old Sam lunch, Mrs. Jones notices that he refuses to eat the cheerios or pieces of banana she has given him. Sam becomes upset when presented with the solid food so Ms. Jones eventually gives him some baby food and a bottle.

Scientific References:

  • Baker, Lane, Angley, and Young. (2007). The relationship between sensory processing patterns and behavioral responsiveness in autistic disorder: A pilot study. Journal of Autism and Developmental Disorders. 38:867-875.
  • Zwaigenbaum, Bryson, Rogers, Roberts, Brian, & Szatmarzi. (2004). Behavioral manifestations of autism in the first year of life. International Journal of Developmental Science. 23:143-152.

Carry around objects for extended periods of time. These items might seem unusual or common.

A child at risk for autism might become particularly attached to or seem preoccupied by a usual or unusual object. For example, a child might insist on carrying multiple balls at once whenever possible, or a child might want to carry her parent’s checkbook at all times. These items might soothe the child and the child might become distressed if prevented from accessing them.

  • Example of a typically developing child: As Mrs. Smith gets Johnny ready for bed, she makes sure that his favorite teddy bear is placed in the crib because her son has a hard time falling asleep without it.
  • Example of a child at risk for autism: As Mrs. Jones gets Sam ready for bed, she attempts to retrieve her keys from her son who has carried them with him all day. When this upsets Sam, Mrs. Jones decides to let him have the keys because she knows he will have a hard time falling asleep without them.

Scientific References:

  • Bishop, Richler, & Lord (2006). Association between restricted and repetitive behaviors and nonverbal IQ in children with autism spectrum disorders. Child Neuropsychology, 12(4&5):247-267.
  • Richler, Bishop, Kleinke, & Lord (2007). Restricted and repetitive behaviors in young children with autism spectrum disorders. Journal of Autism and Developmental Disorders. (37):73-85.
  • Young, Brewer, & Pattison (2003). Parental identification of early behavioral abnormalities in children with autistic disorder. Autism. 7(2);125-143.

Display unusual body or hand movements

A child at risk for autism might move their hands, fingers, or other body parts in an odd and repetitive manner.

  • Example of a typically developing child: Mrs. Smith notes that while Johnny is getting better at throwing a ball, his throw is still very clumsy and he holds the ball awkwardly.
  • Example of a child at risk for autism: Mrs. Jones notes that after throwing the ball, Sam leans over to face the floor and extends his arms straight behind his body with his fingers spread. He repeats this each time he throws the ball.

Scientific References:

  • Bishop, Richler, & Lord (2006). Association between restricted and repetitive behaviors and nonverbal IQ in children with autism spectrum disorders. Child Neuropsychology, 12(4&5):247-267.
  • Osterling, Dawson, and Munson (2002). Early recognition of 1-year-old infants with autism spectrum disorder versus mental retardation. Development and Psychopathology. 14: 239-251.

Play with toys in an unusual manner

A child at risk for autism might use their toys or other objects in a manner different from how they are typically used, or might not actually “play” with toys. A child’s use of these objects might replace typical usages.

  • Example of a typically developing child: While watching Johnny play with a matchbox® car, Mrs. Smith sees him pause briefly to examine and spin the car’s wheels. For the rest of the play period Johnny rolls the car across the floor while saying, “vroom-vroom."
  • Example of a child at-risk for autism: While watching Sam play with a matchbox® car, Mrs. Jones sees him flip the car over and repeatedly spin the wheels while holding the car level with and a few inches away from his eyes.

Scientific References:

  • Richler, Bishop, Kleinke, & Lord (2007). Restricted and repetitive behaviors in young children with autism spectrum disorders. Journal of Autism and Developmental Disorders. (37):73-85.
  • Ozonoff, Macari, Young, Goldring, Thompson, & Rogers (2008). Atypical object exploration at 12 months of age is associated with autism in a prospective sample. Autism. 12(5). 457-472.

Show low enthusiasm to explore new things or appear underactive

A child at risk for autism might not appear to be interested in novel toys, people, or environments.

  • Example of a typically developing child: As Mrs. Smith watches Johnny play at a new park she sometimes has difficulty keeping an eye on him as he moves between play structures, exploring each one. Eventually, he finds a favorite play structure and plays there for the rest of their time at the park.
  • Example of a child at risk for autism: As Mrs. Jones watches Sam play at a new park she sees that he is sitting in one place and running his fingers through the sand. She attempts to encourage him to explore by placing him on various play structures but he becomes fussy and returns to his spot in the sand.

Scientific References:

  • Ozonoff, Macari, Young, Goldring, Thompson, & Rogers (2008). Atypical object exploration at 12 months of age is associated with autism in a prospective sample. Autism. 12(5). 457-472.
  • Pierce & Courchesne (2001) Evidence for a cerebellar role in reduced exploration and stereotyped behavior in autism. Biological Psychiatry. 49(8):655-64.

Seem overly fussy or be difficult to soothe

Children at risk for autism might cry or tantrum more often than other children. They might also begin to cry or fuss without an obvious trigger and/or not be soothed by common calming practices.

  • Example of a typically developing child: While observing Johnny at play with a playgroup, Mrs. Smith sees Johnny bump his head and begin to cry. She immediately goes over to her son, picks him up, and speaks soothingly to him. After a minute or two, Johnny quiets down and is soon eager to return to his play.
  • Example of a child at risk for autism: While observing Sam at play with a playgroup, Mrs. Jones sees and hears Sam begin to cry. Mrs. Jones immediately goes over to her son, picks him up, and speaks soothingly to him. Mrs. Jones is not sure why Sam began crying and her attempts to soothe him are unsuccessful.

Scientific References:

  • Garon, Bryson, Zwaigenbaum, Smith, Brian, Roberts, & Szatmari (2009). Temperament and its relationship to autistic symptoms in a high-risk infant sib cohort. Journal of Abnormal Child Psychology. 37:59-78.
  • Wetherby, Woods, Allen, Cleary, Dickinson, & Lord (2004) Early indicators of autism spectrum disorders in the second year of life. Journal of Autism and Developmental Disorders. 34(5): 473-493.

Toddlers between 12-24 months at risk for
an Autism Spectrum Disorder MIGHT NOT:

Point at things

A child at risk for autism may not point at far away objects in response to your prompts or to try to pull your attention into things they see around them.

  • Example of a typically developing child: While taking her son Johnny on a walk, Mrs. Smith notices that he points to an airplane he hears flying over head.
  • Example of a child at risk for autism: While Mrs. Jones is taking her son, Sam, on a walk, she notices he does not look at or point to a noisy airplane flying over head.

Scientific References:

  • Vostanis, Smith, Corbett, Sungum-Paliwal, Edwards, Gingell, Golding, Moore, & Williams (1998). Parental concerns of early development in children with autism and related disorders. Autism – The International Journal of Research and Practice, 2, 229-242.
  • Baron-Cohen, Cox, Baird, Swettenham, Nightingale, Morgan, Drew, & Charman (1992). Psychological markers in the detection of autism in infancy in a large population. British Journal of Psychiatry, 168, 158-163.

Babble or talk back and forth with another person

Children at risk for autism may not direct their vocalizations to another person in a meaningful way or may not make babbling sounds (e.g., baba, gaga, gada) at all.

  • Example of a typically developing child: When Mrs. Smith asks her son what he wants while feeding him in his highchair, Johnny reaches for the spoon she is holding and responds by saying “dadagabada” in a way that makes her feel like he is speaking his own language.
  • Example of a child at risk for autism: When Mrs. Jones asks her son what he wants while feeding him in his highchair, Sam does not respond and continues to make high-pitched noises while looking at the wall.

Scientific References:

  • Landa, Holman, & Garrett-Mayer (2007). Social and communication development in toddlers with early and later diagnosis of autism spectrum disorders. Archives of General Psychiatry, 64, 853-864.
  • Werner, Dawson, Osterling, & Dinno (2000). Brief report: Recognition of autism spectrum disorder before one year of age: A retrospective study based on home videotapes. Journal of Autism and Developmental Disorders, 30, 157-162.

Try to gain the attention of others

A child at risk for autism may demonstrate fewer attempts to gain the attention of others nearby and may generally appear to not know the coming and going of people.

  • Example of a typically developing child: Johnny crawls over to his mother reading a book, makes noises, and touches her leg until Mrs. Smith looks at him and smiles.
  • Example of a child at risk for autism: Sam crawls around his mother reading a book but never approaches her for attention or acknowledges that Mrs. Jones is there.

Scientific References:

  • Osterling & Dawson (1994). Early recognition of children with autism: A study of first birthday home video tapes. Journal of Autism and Developmental Disorders, 24, 247-257.
  • Osterling, Dawson, & Munson (2002). Early recognition of 1-year-old infants with autism spectrum disorder versus mental retardation. Development and Psychopathology, 14, 239-251.

Smile in response to your smile

A child at risk for autism may not smile or laugh in response to your smile or playfulness although he/she may smile at you on their own and look very happy.

  • Example of a typically developing child: While playing on the floor with his mother, Johnny smiles in response to Mrs. Smith’s smiling and talking to him.
  • Example of a child at risk for autism: Sam only smiles after Mrs. Jones tickles him while playing on the floor.

Scientific References:

  • Zwaigenbaum, Bryson, Rogers, Roberts, Brian, & Szatmari (2005) Behavioral manifestations of autism in the first year of life. International Journal of Developmental Neuroscience, 23, 143-152.
  • Lord, Pickles, McLennan, Rutter, Bregman, Folstein, Fombonne, Libya, & Minshew (1997). Diagnosing autism: Analysis of data from the autism diagnostic interview. Journal of Autism and Developmental Disorders, 27, 501-517.

Make good eye contact

A child at risk for autism may not use his/her eye gaze appropriately to initiate, terminate, or regulate social interactions. Please note, however, some children with an autism spectrum disorder may have appropriate eye contact and gaze.

  • Example of a typically developing child: When making a request, Johnny alternates looking at Mrs. Smith then the treat and then back at Mrs. Smith to convey what he wants.
  • Example of a child at risk for autism: Sam actively avoids eye contact with Mrs. Jones by turning away, pushing away, or closing his eyes.

Scientific References:

  • Wetherby, Woods, Allen, Cleary, Dickinson, & Lord (2004). Early indicators of autism spectrum disorders in the second year of life. Journal of Autism and Developmental Disorders, 34, 473-493.
  • Zwaigenbaum, Bryson, Rogers, Roberts, Brian, & Szatmari (2005). Behavioral manifestations of autism in the first year of life. International Journal of Developmental Neuroscience, 23, 143-152.

Show objects to others

A child at risk for autism may not show objects to another person or may show objects in a partial or inconsistent manner. Typically developing children show objects to others to show enjoyment in the interaction or to initiate an interaction with another person whereas a child at risk for autism may only show objects to others to obtain assistance.

  • Example of a typically developing child: Johnny brings a ball to Mrs. Smith, holds it up to her, and places it in front of her with while looking at her and saying “baaaaa.”
  • Example of a child at risk for autism: Sam holds up a ball and places it in front of Mrs. Jones without coordinated eye contact or vocalizations as though storing it in a safe place for later.

Scientific References:

  • Zwaigenbaum, Bryson, Rogers, Roberts, Brian, & Szatmari (2005) Behavioral manifestations of autism in the first year of life. International Journal of Developmental Neuroscience, 23, 143-152.
  • Vostanis, Smith, Corbett, Sungum-Paliwal, Edwards, Gingell, Golding, Moore, & Williams (1998). Parental concerns of early development in children with autism and related disorders. Autism – The International Journal of Research and Practice, 2, 229-242.

Point to request

A child at risk for autism may not point at a particular object he wants or an object he wants for a particular action.

  • Example of a typically developing child: When Mrs. Smith offers Cheerios or Fishy Crackers, Johnny points to the Fishy Crackers and say “This one” with eye contact.
  • Example of a child at risk for autism: Sam does not point to indicate preference and simply reaches for the Fishy Crackers from Mrs. Jones without saying anything or looking at her.

Scientific References:

  • Vostanis, Smith, Corbett, Sungum-Paliwal, Edwards, Gingell, Golding, Moore, & Williams (1998). Parental concerns of early development in children with autism and related disorders. Autism – The International Journal of Research and Practice, 2, 229-242.
  • Baron-Cohen, Cox, Baird, Swettenham, Nightingale, Morgan, Drew, & Charman (1992). Psychological markers in the detection of autism in infancy in a large population. British Journal of Psychiatry, 168, 158-163.

Respond to their name

A child at risk for autism may not respond to his name when called by parents, friends, or others even after several attempts including familiar noises, implications of touch, or actually being touched.

  • Example of a typically developing child: While playing on the floor, Johnny looks toward Mrs. Smith after she calls his name twice so she can take a picture of him.
  • Example of a child at risk for autism: Sam does not look toward Mrs. Jones after she calls his name, makes a birdie sound, or says “Sammy, I’m gonna get you” and only looks at her when she picks him up and turns him around.

Scientific References:

  • Luyster, Gotham, Guthrie, Coffing, Petrak, Pierce, Bishop, Esler, Hus, Oti, Richler, Risi, & Lord (2009). The autism diagnostic observation schedule – toddler module: A new module of a standardized diagnostic measure for autism spectrum disorders. Journal of Autism and Developmental Disorders, 39, 1305-1320.
  • Werner, Dawson, Osterling, & Dinno (2000). Brief report: Recognition of autism spectrum disorder before one year of age: A retrospective study based on home videotapes. Journal of Autism and Developmental Disorders, 30, 157-162.

Look when you try to direct their attention

A child at risk for autism may not look to an object or another part of the room far away from them in response to a parent shifting their gaze to shift the child’s attention by turning their head and/or pointing.

  • Example of a typically developing child: Johnny looks at a toy car across the room after Mrs. Smith shifts her eye gaze from Johnny to the toy with a slight move of her head toward the car.
  • Example of a child at risk for autism: Sam does not look at the car across the room from him after Mrs. Jones shifts her gaze from Sam to the car, points at the car, or gestures at the car with a point and encouragement.

Scientific References:

  • Luyster, Gotham, Guthrie, Coffing, Petrak, Pierce, Bishop, Esler, Hus, Oti, Richler, Risi, & Lord (2009). The autism diagnostic observation schedule – toddler module: A new module of a standardized diagnostic measure for autism spectrum disorders. Journal of Autism and Developmental Disorders, 39, 1305-1320.

Enjoy cuddling

A child at risk for autism may not enjoy cuddling on a regular basis, although he may sometimes enjoy it.

  • Example of a typically developing child: Johnny frequently seeks out Mrs. Smith to hold him and prefers to be snuggled when Mrs. Smith attempts to put him to sleep in his crib.
  • Example of a child at risk for autism: Sam pushes away from Mrs. Jones when she attempts to cuddle him and only seeks physical contact with her when he is distressed or sick.

Scientific References:

  • Vostanis, Smith, Corbett, Sungum-Paliwal, Edwards, Gingell, Golding, Moore, & Williams (1998). Parental concerns of early development in children with autism and related disorders. Autism – The International Journal of Research and Practice, 2, 229-242.

Show shared enjoyment

A child at risk for autism may show little or no expressed pleasure in an interaction with a parent or another person (although he/she may show pleasure in his/her own actions).

  • Example of a typically developing child: While playing peek-a-boo, a typically developing child may smile and laugh in response to a parent’s facial expressions and words as he/she engages in the activity.
  • Example of a child at risk for autism: A child at risk for autism may not make eye contact, smile, laugh, or clap during peek-a-boo.

Scientific References:

  • Luyster, Gotham, Guthrie, Coffing, Petrak, Pierce, Bishop, Esler, Hus, Oti, Richler, Risi, & Lord (2009). The autism diagnostic observation schedule – toddler module: A new module of a standardized diagnostic measure for autism spectrum disorders. Journal of Autism and Developmental Disorders, 39, 1305-1320.

Say their first word by 12-14 months

A child at risk for autism may not babble (i.e., make consonant/vowel reduplications like “bababa” “gaga” “dama” etc) or say his first spontaneous word or word approximation (e.g., “Dis” for “this”).

  • Example of a typically developing child: Mrs. Smith notices that Johnny spontaneously says “Mama,” “Dada,” “ball,” and “no” correctly during his first birthday party.
  • Example of a child at risk for autism: Mrs. Jones notices that Sam has not used any spontaneous words or word approximations and is generally only making vowel sounds during his second birthday party.

Scientific References:

  • Werner, Dawson, Osterling, & Dinno (2000). Brief report: Recognition of autism spectrum disorder before one year of age: A retrospective study based on home videotapes. Journal of Autism and Developmental Disorders, 30, 157-162.
  • Landa, Holman, & Garrett-Mayer (2007). Social and communication development in toddlers with early and later diagnosis of autism spectrum disorders. Archives of General Psychiatry, 64, 853-864.

Use common gestures

A child at risk for autism may not demonstrate spontaneous, prompted, or imitated use of common gestures (e.g., nodding head for yes, shaking head for no, raising hands in the air when surprised, etc.). In addition, gestures used by children at risk for autism may be odd or unclear.

  • Example of a typically developing child: Johnny shakes his head no when Mrs. Smith asks him to hand her his toy at clean up time.
  • Example #1 of a child at risk for autism: Mrs. Jones notices that Sam does not wave goodbye to her when she waves goodbye to him.
  • Example #2 of a child at risk for autism: Sam takes Mrs. Jones’s by the hand and leads her to the lid of a jar where he places Mrs. Jones’s hand and moves it around without eye contact as if her hand were a tool to be used to open the lid.

Scientific References:

  • Wetherby, Woods, Allen, Cleary, Dickinson, & Lord (2004). Early indicators of autism spectrum disorders in the second year of life. Journal of Autism and Developmental Disorders, 34, 473-493.
  • Vostanis, Smith, Corbett, Sungum-Paliwal, Edwards, Gingell, Golding, Moore, & Williams (1998). Parental concerns of early development in children with autism and related disorders. Autism – The International Journal of Research and Practice, 2, 229-242.

Show interest in other children

A child at risk for autism may have little interest in the communicative (e.g., saying hello), play (e.g., tossing the child a ball), or social (e.g., waving hello) actions of other children.

  • Example of a typically developing child: Mrs. Smith notices that Johnny immediately joins in a game of chase at the park with new children at their playgroup.
  • Example of a child at risk for autism: Sam avoids other children at the park and appears to prefer to play alone when Mrs. Jones encourages him to go play.

    Scientific References:

  • Vostanis, Smith, Corbett, Sungum-Paliwal, Edwards, Gingell, Golding, Moore, & Williams (1998). Parental concerns of early development in children with autism and related disorders. Autism – The International Journal of Research and Practice, 2, 229-242
  • Folstein & Rosen-Sheidley (2001). Genetics of autism: Complex aetiology for a heterogeneous disorder. Nature Reiviews: Genetics, 2, 943-955 (see Box 1: The autism phenotype)

Use a large range of facial expressions

A child at risk for autism may not display or direct facial expressions to others for happy, sad, surprised, scared, curious, or other complex emotions and generally may have little or no expressions beyond emotional extremes (i.e., angry or happy).

  • Example of a typically developing child: Johnny looks at Mrs. Smith with a surprised expression as he finds a new toy in the toy chest.
  • Example of a child at risk for autism: Sam does not show any facial expressions in response to Mrs. Jones showing him a shiny new toy.

Scientific References:

  • Luyster, Gotham, Guthrie, Coffing, Petrak, Pierce, Bishop, Esler, Hus, Oti, Richler, Risi, & Lord (2009). The autism diagnostic observation schedule – toddler module: A new module of a standardized diagnostic measure for autism spectrum disorders. Journal of Autism and Developmental Disorders, 39, 1305-1320.
  • Vostanis, Smith, Corbett, Sungum-Paliwal, Edwards, Gingell, Golding, Moore, & Williams (1998). Parental concerns of early development in children with autism and related disorders. Autism – The International Journal of Research and Practice, 2, 229-242.