Autism and the Brain

Nicole BellomoLindsay Kass

National-Louis University

Autism

• Autism is characterized by abnormalities in three distinct domains:– Deficits in social relatedness– Deficits in communication– Presence of stereotypic/repetitive patterns of behavior

• Literature agrees that the etiology is neurobiological, although much more research is needed to determine the specific areas of the brain involved in ASD.

(Allen, et al., 2008)

Autism Statistics• Prevalence has been reported as high as 1 in 150

children• About 70 – 97% of these students receive special

education services• Some forms of autism appear to be heritable:

– 2-3% of siblings have autism (50-100 times expected frequency in the general population)

– Concordant in 70% of monozygotic twins– Suggested chromosomes involved include 2, 7, 15, 19 and X(Allen et al., 2008, pg. 905 & Carlson, 2008, pg. 497)

Macrocephaly

While slightly smaller than average at birth, the brain of a child with autism is typically 10% larger than a normal brain by 2-3 years of age. After this time, growth begins to slow so that by adolescence the size is typically only about 1-2% larger than normal.

(Carlson, 2008, pg. 498)

Brain Structure

• Specific Areas:– Amygdala– Hippocampus– Cerebral Cortex– Corpus Callosum– Basal Ganglia– Cerebellum– Brain Stem

National Institute of Mental Health Booklet, 2004, autism-watch.org

The Amygdala

Increased Size Decreased Neuron Count

(Mosconi, et al., 2009 and Shumann and Amaral, 2006)

Additional Possible Abnormalities:Excess of cellsAbnormally small cellsDevelopmentally immature neuronsDevelopmental curtailment of Purkinje cellsHyperconnectivity of neurons

(National Institute of Child Health and Development, 2008 and Carlson, 2008, pg. 498)

Brain Functioning

• Reduced neural activity (hypoactivation) in the amygdala: associated with deficits in social perception and/or social engagement (Baron-Cohen et al., 1999; Critchley et al., 2000; Pierce et al., 2001; Wang et al., 2004)

• Hypoactivation of posterior superior temporal sulcus: associated with deficits in joint attention (Pelphrey et al., 2005)

(Allen et al., 2008) & (Schultz & Robins, 2005)

Brain Functioning (cont.)• Functional imaging studies generally find reduced

activation of the dorsal or medial prefrontal cortex in tasks that involve making judgments about other people’s intentions, working memory tasks, perception of emotional expression, and comprehension of speech (Courchesne et al., 2005) as documented in Carlson (2008, p. 498).

• Boddaert and colleagues (2004) found less activiation in the left speech-related areas and dysfunction of specific temporal regions (perception and integration of complex sounds) (Miller, 2007, p. 388).

Brain Functioning (cont.)

• Functioning imaging study by Pierce et al. (2001) found little or no activity in the fusiform face area (found at the base of the brain and is involved in the recognition of individual faces) of autistic adults looking at pictures of human faces.

• Another study by Grelotti et al. (2005) showed no activation of the FFA when the subject looked at photos of faces, but strong activation occurred when looking at Digimon characters.

• Indicating that the lack of activation is caused by a lack of interest in faces, not by abnormalities in the FFA.

(Carlson, 2008, p. 497)

B. Illustration of other areas found to be hypoactive

IFG: Inferior frontal gyrus (hypoactive during facial expression imitation)

pSTS: posterior superior temporal sulcus (hypoactive during perception of facial expressions and eye gaze tasks)

SFG: superior frontal gyrus (hypoactive during theory of mind tasks, i.e., when taking another person’s perspective)

A: amygdala (hypoactive during a variety of social tasks)

FG: fusiform gyrus, also known as the fusiform face area (hypoactive during perception of personal identity)

(Schultz and Robins, 2005)

A. fMRI: (red and yellow) hypoactivation of fusiform gyrus during perception of faces in male with ASD (right) compared to the control (left)

(blue) shows areas more active during perception of nonface objects

Neurocognitive deficits associated with Autism

• Sensorimotor Functions• Attentional Processes• Visual-Spatial Processes• Language Functions• Memory and Learning• Executive Functions• Cognitive Efficiency, Cognitive Fluency, & Processing

Speed• Social-emotional Functioning(Miller, 2007, ch. 16)

Sensorimotor Functions

Fine Motor Coordination• Poor motor imitation ability

(immediate and delayed)• Poor gesture imitation and

producing symbolic imitations

• Poor motor planning• Behaviors that appear to

lack normal goal directedness (stereotypic)

Gross Motor Coordination• Possible gait abnormalities• Motor clumsiness (manual

dexterity different between High Functioning Autism and Autism Spectrum populations)

Motor problems are a characteristic, but not an essential feature of Autism.

Attentional Processes

Disorders of attention may be present, but which area of attention varies among individuals.

• Selective/focused attention- No deficits compared to controls (color used created maladaptive response)

• Sustained attention-Mixed findings• Shifting attention- Mixed findings

Visual-Spatial Processes

Overall, visual-spatial functions appear to be largely intact.

• Visual perception- Greater perceptual fluency• Visual-perceptual organization- Average to

above average performance• Visual search strategies and visual planning

may be problematic

Language FunctionsImpairment in social communication is a major clinical feature. Some have a delay in the development of speech while others

never develop speech.• Deficits in oral expression-Poor use of context, reciprocal and integrated communication,

prosody, language use, and use of unestablished referents-Perseverative questions, echolalia, contributes little new info to

conversations, trouble following the gist of conversations, unusual lexical patterns

• Deficits in receptive language-Poor understanding of idioms, rigid meanings of words, and

poor semantics

Memory and Learning Functions

These functions seem to be only selectively impaired. Impairments include:

• Recency effects on free-recall• Verbal memory• Facial recognition memory• Social memory• Immediate and delayed memory, visual memory

task, and span of apprehension performance all decrease as complexity increases

Executive Functions

Planning efficiency deficits increase with age (no deficits in children under age 12 and increased deficits from teenage years through adulthood).

Executive functioning impairments include:• Regulation of behavior through inhibition and/or

monitoring• Ability to generate multiple novel responses• Cognitive flexibility and verbal fluency (contributes to

deficits in adaptive functioning, such as slower reaction times)

Social Emotional Functions

Impaired social functioning is a hallmark feature.Impaired social skills:• In infancy, poor eye gaze, facial expressions, and body

language• 3-4 year old children, impaired social orienting, shared

attention, responses to emotional cues, and symbolic play

Atypical behaviors:• Stereotyped handling or arranging of objectsPoor social and communication skills can lead to depression

What does this mean for school psychologists?

ChallengesThe current prevalence of autism combined with the lack of

etiological research has left parents searching for information.

• Parents access to internet • Media misrepresentation Additionally, few guidelines have been developed that

clearly outline procedures for developing assessments and implementing research for children with autism.

School psychologists role…• Know the characteristics common to autism • Know the variety of assessments that can be used to

conduct comprehensive evaluations• Know the research behind current interventions and how

they address specific behaviors• Help parents access reliable information and support

services; “Perhaps the greatest assistance that the practicing psychologist can provide families is to candidly discuss options, base recommendations on scientific research and share information about discredited therapeutic approaches” (Kabat et al., 2003).

RIOT

Best Practices in School Psychology (2002)recommends ASD evaluation follow thesame process as other school-based evaluations:• Review Records• Interview Parents and Teachers• Observe in multiple settings• Test with multidisciplinary teams

(Allen et al., 2008, pg. 909)

Who would you put on your multidisciplinary team?

Assessments

• Should consist of a parent report and direct observations.

• Use diagnostic measures that facilitate clinical judgment.

• Assessment battery should be constructed through knowledge of the common characteristics of autism and the neuropsychological domains that correspond to these characteristics (Miller, 2008, pg. 391)

Assessments

• Childhood Autism Rating Scale (CARS): most widely used standardized instrument used for to gather diagnostic criteria. Easy to use and can be used in a wide variety of settings.

• Autism Diagnostic Interview, Revised (ADI-R) and the Autism Diagnostic Observation Schedule (ADOS): comprehensive when used together. Requires special training to administer and interpret.

(Kabot et al., 2003, pg. 29)

Intervention• The earlier the better!

– Better outcomes– Plasticity of brain

• Intensive• Parent Involvement• Focus on generalization

– Independence– Inclusion

• Curriculum focused on social and communication domains• Monitor and assess frequently(Kabot et al., 2003, pg. 30)

In the Field…

Autism research is continually evolving!

• Access and evaluate current research• Use best practices in assessment and

intervention• Continuing Education• Help inform staff and parents

References• Allen, R. A,. Robins, D. L., & Decker, S. L. (2008). Autism Spectrum Disorders: Neurobiology

and Current Assessment Practices. Psychology in the Schools, 45(10), 905-917.• Carlson, N. (2008). Foundations of Physiological Psychology: 7th ed. Boston: Allyn & Bacon.• Kabot, S., Masi, W., & Segal, M. (2003). Advances in the Diagnosis and Treatment of Autism

Spectrum Disorders. Professional Psychology: Research and Practice, 34(1), 26-33.• Mosconi, M. W., Cody-Hazlett, H., Poe, M. D., Gerig, G., Gimpel-Smith, R., & Piven, J. (2009).

Longitudinal Study of Amygdala Volume and Joint Attention in 2- 4-Year-Old Children with Autism. Arch Gen Psychiatry, 66(5): 509-516

• Miller, D. (2007). Essentials of School Neuropsychological Assessment. Hoboken, NJ: John Wiley & Sons, Inc.

• Schultz, R. T., & Robins, D. L. (2005). Functional Neuroimaging Studies of Autism Spectrum Disorders. In F. R. Volkmar, R. Paul, A. Klin, & D. Cohen (Eds.), Handbook of Autism and Pervasive Developmental Disorders: Vol. 1. Diagnosis, development, neurobiology, and behavior (3rd ed., 515-533). Hoboken, NJ: John Wiley & Sons, Inc.

• Schumann, C. M. & Amaral, D. G. (2006). Stereological Analysis of Amygdala Neuron Number. The Journal of Neuroscience, 26(29), 7674-7679.

• National Institue of Child Health and Human Development http://www.nichd.nih.gov/health/topics/asd.cfm