Autism Spectrum Disorders: Core Symptoms and their Development

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Autism Spectrum Disorders Core Symptoms and
their Development Rhea Paul, Ph.D.,
CCC-SLP Southern Connecticut State
University Yale Child Study Center Feb. 11-15,
2008 rhea.paul_at_yale.edu
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Triad of symptoms

• Severe, qualitative impairment in social
  interaction
• Qualitative impairment in communication
• Restrictive, repetitive or stereotyped behaviors
  interests or activities

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Social Interaction

• Gaze
• Attentional patterns
• Eye contact
• Joint Attention
• Imitation
• Emotion and attachment
• Reciprocity
• Play
• Peer Relations

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Eye Contact/Using Gaze to Share
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Eye Contact
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Gaze Patterns
2-year-olds with autism and typical development
viewing video of child playing
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Gaze development in ASD

• Newborns show preference for faces
• prefer eyes by 2 mo.
• Can detect direction of others gaze by 4 mo.
• Children with ASD fail to develop these patterns
• Problems in gaze persist throughout the life
  span, even in HFA
• Are resistant to intervention

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Joint Attention (Intersubjectivity)

• Dyadic infant looks at adult
• Triadic Begins w/ gaze following (6 mo.)
• Progresses to following point (8-10 mo.)
• Then to initiation w/ smiling and pointing at
  objects of interest (12 mo.)
• Lays basis for conversation
• Very low frequency in ASD, appears later than TD
• Can increase with age

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Joint Attention

• Video examples
• JA DD
• JA Autism
• Imitate JA

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Imitation

• Emerges in infancy
• Basis of learning
• Fades in typical development
• Role of mirror neurons
• Less spontaneous imitation and less in
  elicitation settings for children with ASD

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Imitation

• In normal development
• http//www.youtube.com/watch?v-rWKSTtM6Ys
• In ASD
• Haddia example

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Emotion and attachment

• Social referencing
• Comfort seeking
• Sharing emotion with gaze
• Children with ASD
• Do show attachment
• Have difficulty recognizing emotions may be
  related to difficulties in face perception
• Less likely to coordinate expression of emotion
  (smile) with gaze
• Difficulties in empathy (hurt examiner
  experiment)
• Decreased social referencing (robot experiment)

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Sharing emotions
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Sharing emotions
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Reciprocity

• Turn-taking emerges before language
• Back-and-forth nature of social interaction
• Deficits in reciprocity can be seen in both
  verbal and nonverbal individuals

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Reciprocity Preverbal
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Reciprocity Verbal
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Play

• Normal development
• 0-8 mo. All schemes to all objects
• 8-12 mo. Functional play
• 12-18 mo. Autosymbolic play
• 18-24 mo. Single scheme symbolic play
• 24-36 mo. Multischeme symbolic
• 3-5 Pretend, role play
• 5-12 games with rules

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Play in ASD

• Favor exploratory, means-ends, construction,
  stereotypical play over pretend play
• Even symbolic play can be repetitive and
  stereotypic
• May prefer solitary play
• May have difficulty w/ flexibility in games w/
  rules

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Play
http//www.youtube.com/watch?vzAu6ehEGMQcfeature
related
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Peer Relations

• TD children move from family-centered to
  peer-centered social relations
• Children with ASD may
• Prefer to remain solitary
• Be ineffective in approaching and engaging peers
• Make fewer approaches to peers
• Respond less often to peer bids
• Those w/ HFA may
• prefer adults to peers
• Expand interest in peers during adolescence
• Become depressed over loneliness and lack of
  friendships

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Communication Definitions

• Communication
• Message
• Sender
• Receiver
• Language
• Rule-governed
• Conventional
• Symbolic
• Culturally Determined
• Communication
• Speech
• Vocal expression
• Sounds of language

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Language Domains
Content
Content
Form
Content
Form
Use
Use
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Communication is a primary deficit in autism

• Of the triad of symptoms, communication is
  directly involved in two
• Communication deficits are a primary means of
  identifying and diagnosing autism
• Communication in autism involves both delay and
  deviance.
• Primary area of difficulty is in pragmatics
• BUT deficits in other areas can also be seen
  sometimes are similar to those of children with
  specific language impairments (SLI).

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Communication in Typical Development
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Communication Development Capacities at birth

• Vision best at face-to-face range
• Infants show preferences for
• Faces over other visual stimuli
• Speech over other sounds
• Female voices over other voices
• Own mothers voice over other female voices
• Motherese speech-style over adult directed style
• Can discriminate phonemes of native and
  non-native languages

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Typical Communication Development Preverbal
Early Language

• Perlocutionary Stage 0-8 mo.
• 0-4 mo. Preference for faces, speech
• 4-8 mo. Development of vocal communication
• 6-10 mo.
• Emergence of preference for ambient language
  patterns
• Emergence of speech-like sounds

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Communication Development Preverbal Form

• Perception
• 0-6 mo. general speech processing abilities that
  are biologically determined and generic can
  apply to any linguistic input (Eimas et al.,
  1971.)
• 7-12 mo. Change in preferences from those that
  would apply to any language toward ones those
  closely tuned to the sound patterns of the
  environment

• Production
• 0-2 mo. Vegetative sounds
• 2-4 Cooing laughing
• 4-8 mo. vocal play
• 6-10 mo. canonical babble
• 8-18 mo. jargon babble with prosodic contours of
  ambient language

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Perlocutionary Communication
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Illocutionary Stage 8-12 mo.Use

• Development of intentional communication
  expressed through
• Gestures, e.g., pointing
• Vocalization
• Gaze
• Small range of functions expressed
• Proto-imperative
• Proto-declarative
• 2.5 communicative acts/minute
• Emergence of prosodic patterns of ambient
  language.

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Illocutionary Stage Content and Form

• Expressive vocabulary starts slowly
• 12 mo 1-3 words
• 15 mo. 10 words
• 18 mo. 50-100 words first word combinations
• First 50 words include proper and common nouns,
  adjectives, verbs, social terms
• Receptive vocabulary is larger 50 words at 15
  mo.
• Most words have CV shape, one syllable
• Sounds used are same as those found in babble
• /b/, /p/ /m/, /n/, /d/, /h/, /w/.

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Illocutionary Stage Gestures used to express
intents Contact Point
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Illocutionary Stage Gestures used to express
intents Reach
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Illocutionary Stage Gestures used to express
intents Distal Point
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Illocutionary Stage Gestures used to express
intents Show
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Illocutionary Stage Other Conventional Gestures
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Illocutionary Communication
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Locutionary Communication 12-18 mo.

• Same intents expressed with gestures,
  vocalization now expressed with words
• New discourse-related intentions expressed
• request information
• answer
• acknowledge
• 5-7 communicative acts/minute on average

• First words spoken
• First words comprehended outside of routines
• Rapid increase in spoken vocabulary
• 15 mo 3 words
• 18 mo. 50-100 words (/-100)
• 24 mo. 300 words (/-150)
• Word combinations begin when vocabulary50

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Locutionary Development Content

• Early two-word utterances express a small range
  of meanings
• Agent, action, object combinations
• Possession
• Location
• Attributes
• Meanings related to object permanence

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Locutionary Communication
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Communication Development 18-24 mo.

• Repertoire of speech sounds increase
• CVC and multisyllabic words increase many still
  single syllable
• Average child is 50 intelligible
• Average expressive vocabulary size at 18 mo. Is
  100 words (/- 100)
• Multiword utterances increase in frequency
  vocabulary grows
• Understanding of sentences is not far ahead of
  production
• Pragmatic developments
• New discourse-related communicative functions
• Discourse management
• Turns increasing awareness of conversational
  obligation
• Topics 1-2 turns/topic
• Register variation

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18-24 mo. Communication
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Limitations in Communication is ASD
Prelinguistic Level

• Delayed onset of speech (Stone et al., 1994)
• Atypical preverbal vocalizations (Sheinkopf et
  al., 2000)
• Depressed rate of preverbal communication
  (Wetherby, Prizant Hutchinson, 1998)
• Restricted range of communicative behaviours,
  limited primarily to regulatory functions (Mundy
  Stella, 2000)
• Low responsiveness to speech (Osterling Dawson,
  1994)
• Delayed and deviant use of gestures (Dawson et
  al., 1998 Stone, et al., 1997)
• Dearth of pretend and imaginative play (Stone et
  al., 1994)
• Laci of imitation orally, vocally, and verbally
  (Volkmar et al., 1997)

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TD Comment
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ASD Comment
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Developing Language
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Communication Development 24-36 mo. Form and
Content

• Average expressive vocabulary size at 24 mo. Is
  300 words (/-150) word classes include
• Object action words
• Kinship terms
• Spatial terms
• Question words
• Color, shape words
• Grammatical morphemes, verb phrase marking
  emerges some overgeneralization
• Grammatical forms for sentences such as
  questions, negatives are emerging
• Sentence length is 3-5 words
• Intelligibility increases from 50 to 70

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Communication Development 48-60 mo. Form
Content

• Vocabulary at school entry6000 words
• Basic grammatical forms mastered expressively and
  receptively
• few grammatical errors are heard
• Overgeneralization may persist
• Average 4 year is 100 intelligible
• Speech errors may persist, but speech can be
  understood
• Residual errors in /s/, /l/, and /r are last to
  resolve

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Background Pragmatics of Language

• Pragmatic domains
• Communicative functions
• Discourse management
• Register variation
• Presupposition
• Prosody

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Communication Development 48-60 mo. Use

• Communicative functions
• Increase in range of functions
• New genre narration
• Increase in decontextualized talk
• Discourse management
• Requires less support from adults still needs
  some
• Longer turns more turns/topic

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Communication Development 48-60 mo. Use

• Register variation
• New polite forms
• permission requests, permission directives, some
  indirect requests
• 4-7 hints
• Ability to use motherese

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Preschool Conversation
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Early Verbal Communication in ASD

• Pronoun reversals
• Idiosyncratic word use
• Use of immediate and delayed echolalia
  (communication strategy)
• Perseverative conversation
• Atypical voice and prosodic features

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Echolalia

• http//www.youtube.com/watch?vsniGZoVB0R4feature
  related

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Conversation in ASD
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Communication Development in Later Childhood and
Adolescence

• Syntax/Semantics
• Increases in oral and written forms
• Increases in figurative, nonliteral language
• Pragmatics
• Discourse Genres
• Narration
• Persuasion/negotiation
• Exposition
• Ambiguity/sarcasm
• Register variation
• Slang
• Figurative language

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Communication in Youth
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Impairments in Higher Level Language Skills in ASD

• Reduced topic management skills
• appropriate topic termination
• Responding to cues to change topic
• Commenting contingently say something relevant
• Reduced presuppositional skills due to theory of
  mind (ToM) deficits
• Poor ability to share topics
• infer others informational state
• Obsessive, circumscribed interests
• Sparse conversation OR overly talkative about
  special interests
• Gaze and prosodic deficits persist

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Discourse Management Example
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Presupposition Example
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Prosody Example
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Circumscribed Interest Example
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Repetitive behaviors

• http//www.youtube.com/watch?v-6blmKiPe9cfeature
  related
• http//www.youtube.com/watch?vMB9UDDLJfKMfeature
  related

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Controversial Treatments

• Promise to cure the core symptoms of ASD
• Definition of the core deficits often lacks solid
  empirical evidence (e.g., metabolic problems,
  exposures, visual processing)
• Offer vague benefit (e.g., improve focus)
• Lack of empirical evidence
• Reliance on uncontrolled studies, single-case
  testimonials
• Claim that they cannot be studied
• Often claim persecution form the scientific
  establishment
• Staying open-minded

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Gluten- Free Cassien-Free Diet (GFCF)

• Leaky gut -gt peptides crossing blood-brain
  barrier -gt disrupted neurotransmitter breakdown
  -gt increase of opiotoids -gt activity-autism.
• Leaky gut could be caused by yeast overgrowth,
  gastrointestinal disease due to immunization,
  etc.
• No evidence for these causal relationships
• Systematic study of GFCF diet initiated at
  University of Rochester

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Ethyl Mercury (Thimerosal) Exposure

• Danish Natural Experiment
• 1970 1992 petrussis vaccine contained
  Thimerosal
• 1992-1997 same vaccine w/o Thimerosal
• 1997 different petrussis vaccine w/o Thimerosal
• Danish Psychiatric Register Data contrary to
  prediction, no difference in rates of autism was
  found between groups who received Thimeraosal and
  those who did not

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Chelation Therapy

• Hypothesized toxic effects of mercury exposure,
  mercury accumulates in internal organs (hair
  trace analysis)
• Chelation introduction into the blood stream
  agents that bond with specific metals in the body
• Purely hypothetical connection between mercury
  poisoning and autism
• No empirical evidence supporting the claim, no
  reports of curing autism or improving symptoms
  following chelation
• Possible side-effects of chelation washes out
  valuable minerals, very costly diagnostic process
• Two children have died following chelation.

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Supplements

• Assumption that developmental disabilities may be
  caused by innate biochemical errors
• E.g., B6magnesium supplements
• Lack of well-controlled, long-term follow up
  studies
• Possible side effects high dose of B6 possible
  neuromotor side effects in adults, magnesium
  potentially toxic metal in high doses

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Secretin

• Pancreatic hormone assisting digestion
• Cure of autism (Horvath et al., 1998) after
  single injection of the hormone
• Controlled studies secretin has the same effect
  as placebo (Carey et al., 2002 Chez et al.,
  2000 Owley et al., 1999)
• Positive effect on children with autism and
  diarrhea, but no reduction in aberrant behaviors
  no effect on those w/o diarrhea (Kern et al.,
  2002)