Sensory Integration Dysfunction in Individuals with Cognitive Disabilities

for theColeman Institute Workshop

Aspen, COOctober 2001

Lucy Jane Miller, Ph.D., OTRAssociate Professor of Rehabilitation Medicine and PediatricsUniversity of Colorado Health Sciences CenterDirector of STAR Center at The Children’s Hospital, Denver, COlucymiller@frii.com

Acknowledgements It Takes a Village!!

• Roiann Ahn• Grace Baranek• Judy Benzel-

Martin• Teresa May

Benson• Erna Blanche• Julie Bonnell• Pam Buckley• Anita Bundy• Janice Burke• Sharon Cermak• Kelly Church• Ellen Cohn

• Jan Ingebritson• Jane Koomar• Shelly Lane• Mark Laudenslager• Zoe Mailloux• Shanley Mangeot• Kathy McBride• Kent McBride• Jude McGrath-Clarke• Danny McIntosh• Laura Meyer• Debbie Moulton• Andrea Nyhoff• Todd Ognibene

• Wendy Coster• Patti Davies• Winnie Dunn• Pat Fodor• Kate Glover • Linda Greco-Sanders• Kathy Green• Becky Greer • Ed Goldson• Marshall Haith • Randi Hagerman• Barb Hanft• Brian Hinaman

It Takes a BIG Village!!• Diane Parham• Bruce Pennington• Nicki Pine• Chip Reichardt• Marty Reite• Gilana Rivkin• Don Rojas• Sally Rogers• Roseann Schaaf• Mary Schneider• Robin Seger• Janelle Sheeder• Jodie Simon• Susanne Smith

Roley

• Catherine Spence• Clare Summers• Vivian Shyu• Tracy Stackhouse• Peter Teale• Julie Tourigny• Sharen Trunnell• Jeff Walker • Lisa Waterford• Julie Wilbarger

www.SInetwork.org

• What is Sensory Integration Dysfunction (DSI)?

• Is the treatment of DSI effective?

• Is DSI a valid syndrome?

• What are the underlying mechanisms of DSI?

Introduction:

Definitions and Terminology

Importance of distinguishingterms for:

Neuro-physiologic Processes

Sensory Integration Functions

Sensory Integration Dysfunction (DSI)

Neuro-physiologicProcesses vs. Behavioral

Manifestations

processes: are not observed because they occur at the cellular or nervous system level and

behavioral manifestations of these processes, can be observed in sensory integration functional and dysfunctional patterns

The minimum intensity of stimulus at periphery necessary to produce excitation or inhibition.

Peripheral Sensory Threshold

Leads to transmission of the electrical or chemical signal.

Central Sensory Threshold

Exists at periphery at receptor level, at the level of the action potential, and at each central synapse.

Sensory Threshold

Central process in which sensory input from a single sensory system converges on a cluster(s) of neurons, together affecting the activity of the neuron on which they synapse.

Intra-Sensory Integration

Central process in which cluster(s) of neurons receive input from more than one sensory system.

Inter-Sensory Integration

Sensory In tegration

S ensory D iscrim ination

Sen sory M odu lation

Sensory D etection

A Model to Explain Sensory Integration Terminology

Sensory Processing

Sensory Detection

Awareness of sensation is the conscious realization or unconscious awareness of sensation

Sensation ModulationFunction

The capacity to regulate and organize the degree, intensity, and nature of responses to sensory input in a graded and adaptive manner.

McIntosh, Miller, Shyu, & Hagerman, 1999

Discrimination of Sensation

The ability to discern the qualities, similarities, and differences among sensory stimuli, including differentiation of the temporal or spatial qualities of sensory input.

Miller and Lane, 2000

What does the term

“Sensory Integration

Dysfunction” mean?

Atypical processing of sensory stimuli that is severe enough to produce significant difficulties in functional aspects of daily routines and activities.

Sensory Integration Dysfunction

Atypical behavioral responses can occur in several sensory

domains including:

Touch Movement Auditory Visual

Taste Smell Proprioceptive (position

and movement of joints)

Decreased Social Skills & Participation in Play

Poor Self-confidence & Self EsteemDifficulties with Daily Life Skills at

Home & SchoolAnxiety, Poor Attention, Poor

Regulation of Reactions to OthersPoor Gross, Fine or Sensory Motor

Skill Development

*Parham and Mailloux, 1996

Hypothesized Relation among DSI Patterns

DyspraxiaDyspraxia Sensory ModulationSensory ModulationDysfunctionDysfunction

Other DSI Other DSI PatternsPatterns

DysDys

SMDSMD OtherOther

Difficulty in planning and performing a novel (non-habitual) motor act or series of motor actions that is severe enough to create difficulties in daily routines and activities.

Dyspraxia

Problem in capacity to regulate and organize responses to sensory input in a graded and adaptive manner that is severe enough to create difficulties in daily routines and activities.

Sensory Modulation Dysfunction (SMD)

Is sensory modulation

disorder a unitary

construct?

Types of SMD Over-sensitivity - responses to sensation are greater

than those typically demonstrated by others under same circumstances

Under-sensitivity - responses to sensation are less than those typically demonstrated by others under same circumstances

Passive vs. active responses

Differences between sensory systems

Over-Sensitive Under-Sensitive

Active Defensive Responses Seeks Sensation

Passive Anxious/Withdrawn Lethargic/Depressed

Is InterventionEffective?

Need for randomized clinical trial to compare treatment models

Randomized Clinical Trial

GroupMembership

First10 weeks

Second10 weeks

Third10 weeks

Group A OT ActivityProtocol

--

Group B Activity Protocol

OT --

Group C Wait-List OT ActivityProtocol

Is SMD a

valid

syndrome?

What is a syndrome?

“A syndrome is a cluster of symptoms that reliably co-occur and identify subtypes of patients who are homogeneous.”

Pennington, 1991, p. 24

“If a syndrome is valid, it will

satisfy tests of both convergent

and discriminant validity

across levels of analysis.”

Pennington, 1991, p. 24

Validating A SyndromeConverged and Divergent

Evidence Etiologies Brain Development Processing Abilities and Symptoms Developmental Trajectory Effects of Treatment

ADHD

Anxiety

Autism

Schizophrenia

DepressionDyspraxia

OCD

Childhood Developmental Disorders:Syndrome Validation

SMD

FXS

Randy Ross, M.D.

What are the

underlying

mechanisms in

DSI?

Can we develop a reliable

laboratory paradigm to

measure sensory

reactivity?

EDR

A psychophysiological measure

that assesses the extent of

response to stimuli by measuring

changes in the electrical

properties of the skin.

Skin becomes more electrically

conductive as a result of

eccrine sweat gland activity

which increases EDR.

Eccrine sweat glands are

innervated by cholinergic fibers

of the SNS, thus measuring

EDR provides an index of SNS

activity.

Andreassi, 1989; Dawson, 1995; Fowles, 1986

Startling

Threatening

Aggressive

Defensive Feelings

Emotional Events

?Sensory Events?

Sensory Challenge Protocol

Ten contiguous trials in each of five sensory systems

olfactory (wintergreen oil) auditory (siren) visual (strobe light) tactile (feather on face) vestibular (chair tilted backwards)

EDR recorded after each sensation

EDR Variables

Number of Responses Amplitude of Responses Number of trials to which an

individual responds

Habituation: a decrease in response with repetitive stimulation

Mean Magnitude in Log10(micromhos)for FXS and TYP

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

1 2 3 4 5 6 7 8Trials

Log

Mag

nitu

de o

f Pea

k (m

icro

mho

s)

Fragile X

Typical

Group

Miller et al., 1999

Proportion Responding overProportion Responding overTrials for FXS and TYPTrials for FXS and TYP

00.10.20.30.40.50.60.70.80.9

1

1 2 3 4 5 6 7 8Trials

Prop

ortio

n w

ith R

espo

nse

Fragile XTypical

Group

Miller et al., 1999

0

0.01

0.02

0.03

0.04

0.05

0.06

1 2 3 4 5 6 7 8

Trials

Log

Ampl

ititu

de o

f Mai

n Pe

ak (m

icro

mho

s)

Typical

FXS

Autism

Mean Amplitude of Mean Peak Across Modalities for Children with FX and Autism Compared to Typical Children

Miller et al., 2001

Mean Amplitude of Mean Peak for Individuals with Fragile X Syndrome and Autism in Study 2

TRIAL

87654321

Est

imat

ed M

argi

nal M

eans

.6

.5

.4

.3

.2

.1

COND

FXS=1.00

AUT=5.00

Subtests of SSP

• Tactile Sensitivity• Taste/Smell Sensitivity• Seeks Sensation• Auditory Filtering• Visual/Auditory Sensation• Low Energy / Weak• Movement Sensitivity

Subtests of SSP

• Tactile Sensitivity• Taste/Smell Sensitivity• Und-resp / Seeks Sens• Auditory Filtering• Visual/Auditory Sensation• Low Energy / Weak• Movement Sensitivity

Short Sensory Profile Ratings for Children with FXS and Autism Compared to Typical Children

(Aut=8; FXS=25; TYP=25) - 1999

-5

-4

-3

-2

-1

0

1

2

Taste ** ^ Movement Visual Tactile * Auditory Low Energy * Under-Responsive ^̂

Short Sensory Profile Subscales

Z Sc

ore Typical

FXSAutism

““It may be those who do most, It may be those who do most,

dream most.”dream most.”

Stephen Leacock (1869-1944)Stephen Leacock (1869-1944)

““To be conscious that you are To be conscious that you are

ignorant of the facts is a great ignorant of the facts is a great

step to knowledge.”step to knowledge.”

Benjamin Disraeli (1804-1881)Benjamin Disraeli (1804-1881)

““The end of science is not to The end of science is not to

prove a theory, but to prove a theory, but to

improve mankind.”improve mankind.”

Manly P. Hall (born 1901)Manly P. Hall (born 1901)