1. Catherine Cavaliere, PhD, OTR/L New Jersey Occupational Therapy Association Annual Conference October 1, 2011

2.  Clinical Hypothesis:  “ Sensory integration intervention fosters neural adaptations that thereby support behavioral adaptations within the environment in children with autistic spectrum disorders(ASD).”  Core assumption of SI theory:  “The goal of sensory integration intervention is to improve the efficiency of the nervous system in interpreting sensory information for functional use.” (Parham & Malliouz, 2000)  Treatment efficacy study – pre/post test - measure of neurophysiologic change

3.  Lack of research to support the theoretical assumption that SI intervention fosters neural change  Lack of information in literature as to how children, with and without autism, respond to sensation, neurophysiologically, PERIOD!

4.  “How do children with ASD respond to sensation neurophysiologically? Is there a relationship between this and their behavioral responsivity to sensation?”  Measure and methods  Dr. Lucy Jane Miller and colleagues – Sensory Challenge Protocol (SCP )

5. DSM IV  Social Interaction  Marked impairment in nonverbal behavior  Failure to develop age appropriate peer relationships  Lack of spontaneous seeking to share interests with others  Lack of social or emotional reciprocity  Communication  Delay in or lack of spoken language  Marked impairment in conversational skills  Stereotyped use of language  Lack of age appropriate pretend or social play  Stereotyped Patterns of Behavior  At least one restricted pattern of interest  Inflexible adherence to routines  Stereotyped or repetitive motor mannerisms  Preoccupation with parts of objects (American Psychiatric Association, 1994)

6.  70-97% of children with ASD – atypical patterns of sensory processing (Ornitz, 1989; Adrien et al., 1992, Eaves et al., 1994; Kientz and Dunn, 1996; Greenspan and Wieder, 1997; Tomcheck and Dunn, 2007)  Children with ASD – early signs of deficits in sensory processing – central to ASD diagnosis (Baraneck, 1999)  Children with ASD respond differently to sensation, behaviorally, than do children without ASD (Dunn and Kientz, 1996; Dietz and White, 2000)  ASD – most severe sensory processing disorders (Bagnato and Neilsworth, 1999)

7.  Patterns of physiological responsivity (EDA) that are different than typically developing children and other groups of children with behavioral difficulties with sensation  Decreased magnitude of EDR – hypo-responsivity (Miller et. al., 2000)  2 groups – High arousal – higher magnitude EDR; Low arousal – lower magnitude EDR – heterogeneous group ( Schoen,S.A, Miller, L.J., Brett-Green, B., &Hepburn, S.L., 2008)  Lower vagal responses to auditory and tactile information (Schaaf and Benevides, 2006) (McIntosh, D., Miller, L. J., Shyu, V., & Hagerman, R., 1999; Miller et al., 1999; Donelon,- Mangeot et al., 2001; Miller, L.J., McIntosh, D.N., Reisman, J.E., Simon, J., 2001; Schaaf, R.C.,& Benevides, T., 2006; Schoen, S.A, Miller, L.J., Brett-Green, B., &Hepburn, S.L., 2008)

8. “The objective of therapy for the autistic child is to improve sensory processing so that more sensations will be effectively “registered” and modulated, and to encourage the child to form simple adaptive responses as a means of helping him to learn and to organize his behavior… As we continue to treat autistic children, we shall find out more about their neurologic problems and develop ways of “reaching” their brains with sensory experience.” (Ayres, 1979)

9. Neuro-physiologic state Behavioral state– attention, arousal Adaptive Interactions Occupational Performance

10. Autonomic Nervous System Parasympathetic Nervous System Restorative functions Cardiac Vagal Tone Respond to all environmental situations Sympathetic Nervous System Highly active stressful situations Electrodermal Activity

11.  Parasympathetic nervous system’s (PsNS) modulation of heart rate via the vagus nerve  Respiratory Sinus Arrhythmia(RSA) - rhythmic heart rate variability within spontaneous breathing  2 functional aspects of CVT:  Baseline – rest – high CVT  Vagal regulation – change from baseline to respond to environment – drop in CVT  More variability indicating more efficient neural control  physiologically able to meet the demands of any situation – adaptive interactions (Porges, 1992; 1995)

12. Physiologic Variability Physiologic Flexibility Behavioral Flexibility Adaptive Interactions (Porges, 1992;1995)

13. Porges (1995) Healthy NeonatesHigh Risk - NICU

14.  Higher baseline VT correlated with greater self-regulation and more positive developmental outcomes ( Porges et al, 1996; Fox, 1989; DeGangi et al, 1991; Fox and Porges, 1985; Huffman, L.C., Bryan, Y.E., delCarmen, R., Pedersen, F.A., Doussard-Roosevelt, J.A. & Porges, S.W., 1998; Gunnar, M.R., Porter, F.L., Wolf, C.M., Rigatuso, J. & Larson, M.C., 1995; Stifer and Fox, 1990; Richards, 1985)  Fragile x– lower baseline (less heart rate variability) VT than boys without (Boccia &Roberts,2000)  SMD – lower baseline vagal tone than children without (Schaaf et al., 2003; 2010)  ASD – lower baseline vagal tone than typically developing children (Schaaf and Benevides, 2006)  Significant relationship between vagal tone and adaptive behaviors - ASD - lower vagal tone had less adaptive behaviors (vineland adaptive behavior scales) (Schaaf and Benevides, 2006)

15.  More consistency in suppressing vagal tone in response to environmental stimuli/task, the greater the social and attentional capacities and more even temperament (Porges et al, 1996; Huffman et al, 1998; Fox, 1989; Calkins, 1997; Suess, P.E., Porges, S.W. & Plude, D.J, 1994; DeGangi et al., 1991;Gunnar et al., 1995; Stifter and Fox.,1990; Richards, 1987 )

16. AuthorSubjects - ageTesting periodResults - VT Fracasso et al., 1994 5,7,10,13 monthsEvery 3 months – 4 testing sessions Moderate stability (r=.50-.55) Stifter & Fox, 1990Neonates, 5 months 5 months apart – 2 testing sessions Not Stable (r=.07) Fox & Field, 19893yrs6 months apart - 2 testing sessions Stable (r=.89) Calkins & Keane, 1994 2 yrs, 4.5 yrs2.5 years apart – 2 testing sessions Moderate stability (r=.57) Doussard- Roosevelt et al., 2003 5-6yrs2 wks apart – 3 testing sessions Moderate stability (r=.58) Porges, 1992NICU Neonatesfirst day off ventilator, every day for 5 days – 6 testing sessions Stable (r=.90)

17. AuthorSubjectsTaskResults - VT Calkins & Keane, 2004 2yrs, 4.5yrsAttention, empathy, frustration, problem solving No stability (r=.05-.29) Doussard- Roosevelt et al., 2003 5 yrs – once a wk – 4 wks Negative affect elicitor task Modest stability wks 1-2 (r=.40) No stability second 2 wks (r=.08-.25) El-Sheik, 20059,11 yrsCognitive task Emotional task Stability – cognitive task – (r=.60) No stability – emotional task – (r=.06)

18.  Infants/ young children with high baseline vagal tone demonstrate greater self-regulation  Children with ASD and SMD have lower baseline vagal tone than children without  Infants/ young children who consistently suppress vagal tone in response to a challenge demonstrate greater attentional and social interaction skills and more even temperament  Reliability– mixed results

19.  Reliability of vagal tone has not been established  Limited information on vagal tone in older children (4+)  Limited information on vagal tone in various diagnostic groups including autism  Inconclusive information on the relationship between physiologic responsivity(CVT) and behavioral responses to sensation

20.  Is cardiac vagal tone a reliable measure of physiologic responsivity to sensation in both typically developing children and children with ASD?  Do children with ASD respond differently (behaviorally and physiologically) to sensation than typically developing children?  Is there a relationship between the behavioral and physiologic responses to sensation in children with and without ASD?

21.  Sensory Profile (Dunn, 1999)  Caregiver questionnaire  Profiles a child’s behavioral responses to sensation  Construct validity – sensory processing (Dunn, 1997)  Discriminant validity - differentiate children with ASD from children without autism, ADHD, SMD (Kientz &Dunn, 1997; Ermer & Dunn, 1998)  Positively correlate with physiologic measures of sensory responsivity (EDR) using the SCP (Miller et al.,1999;2000)

22.  Test re-test/ Multifactorial repeated measures design  Independent variables  Group  Sensation (SCP)  Testing session  Dependent variables  Physiologic responsivity to sensation (CVT)  Behavioral responsivity to sensation (SSP)

23.  Experimental group  Males with ASD - 4-11 yrs.  No other developmental/neurological conditions  No medications  Control group  Typically developing males – 4-11 yrs.  No developmental/neurological conditions  No medications

24.  39 boys (16 typically developing; 23 with ASD)  Excessive artifact (n=5)  Technical Difficulties (n=3)  Inability to tolerate testing (n=4)  15 typically developing boys; 11 boys with ASD  Typically developing (TD)– 8.7 years  ASD – 7.3 years

25.  Psylab stand alone monitor (SAM) acquisition and analysis system (Contact Precision Instruments)  Heart rate and electrodermal responsivity  Synced with the Sensory Challenge Protocol  MxEdit analysis program (S.Porges,1985)  heart rate converted to vagal tone index  artifact identification and editing

26.  Five domains of sensation (vestibular, auditory, visual, olfactory, tactile)  10 trials of each sensation – 3 secs per trial  15-19 sec. between each trial – random intervals  20 secs between domains  Baseline and Recovery  15 mins without stopping  Testing can be paused  Domains can be skipped

27.  Meet/greet parents; complete forms  Acquaint child with testing environment  Explain testing procedures in age appropriate language  Child signs assent  Child seated - electrodes placed on child  SCP started  End of SCP child picks a small gift

29.  Question 1: Is cardiac vagal tone a reliable measure of responsivity to sensation in typically developing children and children with ASD?  Intraclass correlation Coefficient (ICC)  Baseline measures of cardiac vagal tone  Vagal changes in response to sensations

30.  Question 2 : Do children with ASD respond to sensation (behaviorally and physiologically) differently than typically developing children?  Repeated Measures ANOVA – within group patterns of responsivity  Multivariate ANOVA – between group differences – SCP and SSP

31.  Question 3 : Is there a relationship between physiologic and behavioral responses to sensation in children with ASD and typically developing children?  Pearson Correlation Coefficient –vagal scores SCP and SSP scores

32. Question 1: Is cardiac vagal tone a reliable measure of responsivity to sensation in typically developing children and children with ASD?

34. Question 2 : Do children with ASD respond to sensation (behaviorally and physiologically) differently than typically developing children?

35.  Baseline - t(20)=2.58, p=.018  ASD – lower baseline vagal tone – less heart rate variability at rest  Covariate  TYP (M=6.80, SD=.981)  ASD group (M= 5.77, SD=1.27)

36. F=3.04, p=0.13

37. P=.008

38. SSP Sig._(a)__ TYP ASD MSDMSD SSP total175.015.4128.016.4.000 Tactile32.32.528.45.1.013 Taste/Smell18.55.511.66.2.011 Movement sensitivity13.82.414.6.81.298 Under resp./32.33.018.34.2.000 seeks sensation Auditory Filter26.92.917.05.7.000 Low energy28.64.121.67.7.012 Visual Auditory24.21.716.44.5.000 ___________________________________________________________ ________ a Adjustment for multiple comparisons: Bonferroni

39. Question 3: Is there a relationship between physiologic and behavioral responses to sensation in children with ASD and typically developing children?

40. SSPSCP domainr_______________ TYP/ASD sessions combined SSP totalvestibular.510 Auditory vestibular.526 Visual/auditoryvestibular.668 Visual/auditoryolfaction.509 Visual/auditorytactile.558 Visual/auditoryav. response.542 Visual/auditoryvestibular.569 ASD sessions combined Visual/auditorytones.627 ASD session 2 Visual/auditorysirens.555 Visual/auditoryolfaction.606 Visual/auditorytactile.551 Visual/auditoryvestibular.708 Visual/auditoryav. response.613 ________________________________________________________________________

41.  ASD - 99.9% of the vagal responses to sensations across sessions were correlated (<.75) – Ex: visual 1 to olfaction 2  Little physiologic variability across time and across sensations  TYP- 77.5% - more variability across time and across sensation

42.  Overall high stability  ASD - high stability – little variability across time (.819-.916)  TYP- mixed stability – more variability across time (.525-.923)

43.  ASD – sig. lower baseline vagal tone than TYP – less heart rate variability at rest  Supports previous findings (Schaaf et al., 2003; 2010)  Supports reliability findings- pattern of less physiologic variability - ASD

44. Less Physiologic Variability Less Physiologic Flexibility Less Behavioral Flexibility Rigid/ inflexible behaviors Decreased Adaptive Interactions (Porges, 1992;1995)

45. F=3.04, p=0.13

46.  Vestibular system – central integrator (Cool, 1987) -  Spatial map – body, head, position and orientation - understand our environment in relation to self  “reference base “against which all sensory input and motor output must be evaluated ( Cool, 1987)  CN VIII - posterior parietal lobe (cerebellum and brainstem)  “bridge” between sensory inputs and motor outputs (Ayres, 1979)  Only sensory system that also has direct motor innervations (CN VIII) at spinal level – muscle tone and arousal – low in ASD (Miller et. al, 2001)

47.  Stereotyped behaviors – body sense driven (vestibular, proprioceptive and tactile)  Vestibular - critical role as central integrator  Examples: body rocking, head banging, darting, rigid inflexible  Stereotyped behaviors - seeking out vestibular stimulation (Bender, 1947, 1956).  Clinically – stereotyped behaviors - child’s attempt to seek out vestibular input  Treatment – large vestibular component  Goals of treatment - modulate arousal; increase body awareness; improve sensory modulation; attention and interaction

48.  ASD - demonstrated hypo-responsivity to sensation (Miller et. al., 2000)  Our findings support this – physiologic hypo- reactivity to vestibular information as compared to TYP  Results - provide preliminary evidence to support this clinical assumption : Stereotyped behaviors - fulfill a need for additional vestibular input in order to make sense of their environment

49.  ASD – sig. lower scores on all sections of SSP except movement sensitivity - TYP scoring lower  Vestibular Based – body position, orientation  Questions related to safety awareness: “ Becomes anxious/distressed when feet leave ground” “Fears falling or heights” “Dislikes activities where head is upside down”  TYP –more behaviorally sensitive to movement because they more efficiently react to vestibular information thereby providing them with a greater safety awareness and better body awareness

50. Stereotyped Behaviors Less physiologic reactivity to vestibular Less behavioral reactivity to vestibular Seek out vestibular input

51. SSPSCP domainr_______________ TYP/ASD sessions combined SSP totalvestibular.510 Auditory vestibular.526 Visual/auditoryvestibular.668 Visual/auditoryolfaction.509 Visual/auditorytactile.558 Visual/auditoryav. response.542 Visual/auditoryvestibular.569 ASD sessions combined Visual/auditorytones.627 ASD session 2 Visual/auditorysirens.555 Visual/auditoryolfaction.606 Visual/auditorytactile.551 Visual/auditoryvestibular.708 Visual/auditoryav. response.613 ________________________________________________________________________

52.  Visual/auditory section- single sensory system  “holds hands over ears to protect from loud sounds”  “is bothered by bright lights”  “covers or squints eyes to protect from light”.  Other sections – multimodal  “has a weak grasp”  “has difficulty paying attention”  “has difficulty standing in line close to other people”  SCP domains – single system based  Multimodal sensory experiences to SCP

53.  Children with autism demonstrated less reactivity to vestibular information both physiologically (vagal responses )and behaviorally (score on movement sensitivity section)  Support this clinical assumption that the stereotyped behaviors - fulfill a need for additional vestibular input in order to make sense of their environment  relationship between physiology and behavior

54.  Small sample size  Not age matched  Initial testing anxiety

55.  Preliminary info on reliability of vagal tone  Differences in physiologic responsivity between groups – ASD less physiologic variability  Relationship between physiology and behavior

56. Combined these findings provides preliminary evidence to support the theoretical and clinical assumptions that neurophysiologic state affects behavior

57.  Replicated - larger sample size  Compare these results to SNS measures  Modify the SCP to include some multimodal sensory experiences  *Intervention studies

58. “The objective of therapy for the autistic child is to improve sensory processing so that more sensations will be effectively “registered” and modulated, and to encourage the child to form simple adaptive responses as a means of helping him to learn and to organize his behavior… As we continue to treat autistic children, we shall find out more about their neurologic problems and develop ways of “reaching” their brains with sensory experience.” (Ayres, 1979)

59.  Dr. Genevieve Pinto-Zipp, EdD, PT  Dr. Susan Simpkins, EdD, PT  Dr. Valerie Olsen, EdD, PT  Dr. Raju Parasher, EdD, PT  Barbara Schupak, OTR/L, MPH  Michele Parkins, MS/OTR/L

60.  Dr. Lucy Miller, PhD, OTR/L  Dr. Roseann Schaaf, PhD, OTR/L  Teal Benevides, MS/ OTR/L  Celebrate the Children School - Michele Parkins, MS/OTR/L  Pediatric Therapeutics – Missy Briody, MS/OTR/L  Bergen Pediatric Therapy – Lisa Koo, MS/OTR/L

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