Effectiveness of Pivotal Response Treatment: Plasticity of emotion regulation in young children.

Children with an Autism Spectrum Disorder (ASD) experience severe problems in
social functioning which pose a serious threat on the development of several
different domains of general functioning. To reduce the impact of the ASD on
the development of these children it is of major importance to be able to
influence their social competencies in a positive matter. For example,
interventions that aim to enhance the motivation for interaction by early
stimulation of positive interactions between parents and children using Pivotal
Response Treatment (PRT) proves to provide favorable results. PRT is an
established and scientifically supported treatment protocol aimed at increasing
the motivation for interaction in children with ASD by stimulating the
interaction between parents and children. (Coolican, Smith, and Bryson, 2010;
Smith, Koegel, Koegel, Openden, Fossum, and Bryson, 2010). For a more detailed
description of PRT and its content, see Appendix I. Previous research on PRT
has shown improvements in social interaction and even a decrease in overall
autism symptoms in a proportion of the children. However, as with most
treatment programs these results do not apply to every child that receives PRT
(for an overview on empirical support for PRT see Koegel, Koegel, and Brookman,
2003). For this reason it is of great importance that besides determining
whether an intervention is effective, it may be even more important to
determine how and in what way an intervention as PRT is effective and for which
children.

In order to understand the mechanisms of effectiveness it is important to have
optimal knowledge on the underlying cognitive and affective processes that
contribute to the motivation for social initiative and to the quality of the
social interaction. With this knowledge, we can identify building blocks of the
ASD phenotype that can be influenced by treatment and use this knowledge to
identify the subgroup of children that show a high response to treatment.
Studies on cognitive and affective mechanisms that are considered relevant for
emotion regulation and the regulation of social adaptability show that there
are considerable individual differences between children with ASD. It is
important to study these individual differences as this knowledge can help in
A) elucidating individual vulnerabilities in the social-emotional development
and related individual differences in response to treatment and B) identifying
how changes in cognitive and affective functioning relate to changes in ASD
symptoms in response to intervention.

It is clear from parental report and clinical observation that children with
autism show a high level of emotion regulation problems, sometimes react
intense and highly anxious in situations that are stressful or otherwise, show
the opposite, very bland affect in social interaction. However, thus far it has
remained largely unclear to which extend these observable behaviors are related
to underlying problems in affect regulation, as expressed in a potential
imbalance in affect, reflected in heart rate, skin conductance and cortisol
responsivity, and the cognitive skills of these children to be able to regulate
this arousal. These are core mechanisms in behavior regulation and social
adaptivity. This study is innovative in the use of such objective affect
regulation measures, which can provide insight into affect development beyond
the limited information that can be gained from qualitative measures,
self-report or reflection in young children with ASD.

Besides studying this in children with autism, it is of great importance to
include their parents in this study and to look more closely at the
parent-child interactions as this may highly impact the development of affect
regulation in children. In other words, this study also focuses on the quality
of attunement between parent and child.

This study has two main objectives. One objective is to investigate which
cognitive and affective mechanisms can be influenced through treatment which
leads to improved social functioning. We will use a carefully selected set of
behavioral, neuropsychological, and neurobiological tests focusing on measures
related to the functioning and regulation of affective arousal. Specifically,
concerning these underlying mechanisms of social functioning, we hypothesize
that cognitive and neurobiological factors that contribute to the regulation of
behavior and emotion are related to the effectiveness of treatment (i.e.
mediating the effect of PRT on social adaptation) and thus will be influenced
by PRT. Which components moderate this effect is topic of this study.

The second objective of this study is to define the parent and child
characteristics that predict changes in functioning of children with ASD, i.e.
the effectiveness of treatment. The focus lies not necessarily on proving
effectiveness of treatment for ASD, previous research has already proven this.
Therefore, the proposed research is not an effect study, but a study on the
applicability (for which children and parents PRT is most effective) and the
underlying working mechanisms (on which domains PRT has an effect). Concerning
the predictors of treatment efficacy, our hypothesis is that factors that
contribute to the regulation of behavior and emotion play an important part in
the effectiveness of treatment and are thus predictors for PRT efficacy. An
important factor in this is the parent-child relationship. For example, the way
parents regulate stress is of influence on the quality of the interaction
between parent and child and is thus of influence on the social behavior and
emotions of the child.

These two main objectives can be divided into two sub studies, one focusing on
the child characteristics and the other on the parent characteristics.

See protocol pages 15 and 16.

The study will be conducted at the Centre for Autism, where PRT is already part
of the clinical activities. We would like to stress that this study is an
evaluation of a standard clinical protocol at the Centre for Autism. Therefore,
this study will not affect the regular procedure of clinical care, and there
are no costs involved for participants except for those that are part of the
regular clinical care. The design of the study is a longitudinal, randomized
controlled trial (RCT), in which half (n=30) of the children with ASD will
receive PRT treatment during the study and the other half (n=30) will form a
waiting list condition and will receive PRT after the study. The maximum
waiting time is 6 months, which corresponds the typical waiting list time at
the Centre for Autism. Assignment to either the PRT condition or the waiting
list condition, will be randomized alternately.
Again, the waiting list condition is needed to relate any changes in social
functioning, ASD symptoms and affect regulation in the ASD group specifically
to PRT. A non-clinical control group (i.e. boys and girls from the general
population) is needed to test areas of deficits, dysfunction and development in
the children with autism as compared to typically developing peers.

Children with autism and their parents will all (eventually) receive PRT. The
duration and amount of treatment sessions is equal for all participants, i.e.,
children and their parents will go to the Centre for Autism once a week during
a period of 6 months.
The phasing is different for all groups. The Centre for Autism has a waiting
list of 6 months for the start of PRT, so that some families will start PRT
later than others. This waiting list allows us to compare children that have
had the PRT to children that have not received PRT yet.

PRT is recommended for certain children and their families after careful
deliberation in the diagnostics meeting at the Centre for Autism. PRT is
particularly suited for children who have developed little or no speech, taking
into account the load for, and the capacity of the parens (are they Dutch, or
English speaking, do they have the time to invest in the PRT etcetera). After
this first screening, the therapist will set up a treatment plan in which, in
consultation with parents, the goals of the PRT will be recorded. These goals
will be fit to meet the treatment demand that parents have, and taking into
account tthe needs and abilities of the child.

Benefits
Healthy control children plus their mother will receive a travel allowance for
both visits to Leiden University. In addition, parents will receive a gift card
with a value of 30 euro*s after the first visit, and a gift card of 50 euro*s
after the second visit. The children will receive a small present at the end of
each session as gratitude for their cooperation in the study.
The children with autism plus their parents, both in the PRT and waiting list
condition will not receive a travel allowance or financial reward, because this
study is incorporated in the regular appointments at the Centre for Autism and
does not require them to come to the centre more often than usual. The children
will receive a small present at the end of each session.

Burden
There are no risks involved in the proposed study. Children and parents from
the ASD group already have received the permission to start the PRT training at
the moment they enroll in the study. In addition to the PRT training, 3
measurement moments of in total 9 hours are added, in which both the mother and
the child are tested (i.e. parallel).
Children and mothers in the control group will not be asked to participate in
the PRT and will have only 2 measurement moments, the second time point being 6
months after the first. In total, a time investment of 7 hours is asked from
the healthy control group, in which both the child and the mother are tested.
In reward, parents will receive travel allowance and a gift card with a value
of 30 euro's for the first visit and of 50 euro's for the second visit. Also,
children will receive a small present at the end of each session as gratitude
for their cooperation in the study.
In addition, if requested by their clinician, parents can give permission to
send the results on the cognitive performance of their child to the clinician.

Group relatedness
A typically developing group of children plus their mother is needed in order
to quantify change in social behavior over time, i.e. does the treatment group
show a change in deviation from typical development. At baseline and follow-up
we will quantify to what degree social behavior in ASD children is different
from typically developing children. By comparing these deviation scores from
baseline to follow-up, we will be able to assess to what degree children with
ASD have improved. Data from typically developing children and their parents in
also needed to identify 1) responder profiles, i.e. a profile of strengths and
weaknesses in the ASD group as compared to a typical group and 2) calculate
deviations in affect regulation mechanisms in the ASD group over time as
compared to normal development.
In order to assess whether changes in affect regulation or social behavior are
the result of PRT, a clinical control group is needed, consisting of ASD
children (and their parents) who are on the waiting list for PRT during this
study.
Choosing this specific age group (three to six year olds) is crucial to this
study because 1) it is of great importance to study the mechanisms of social
and emotional functioning whilst they are still in development and susceptible
for positive influences through treatment and 2) because treatment should start
as early as possible since studies have shown that this will benefit the
treatment outcomes significantly.

General Remark
It should be noted that a unique aspect of this study is that we incorporate
not only the performance on a cognitive level, but also underlying affective
mechanisms of emotion regulation processes in a population that experience
profound difficulties in this area. Because of this multi-level approach, the
list of measurement instruments is quite extensive. Therefore, while selecting
the measurement instruments for this study, great care was given to the
suitability of the tasks for this specific target group and the healthy control
children. Besides considering the age range, the weak language development and
the restricted attention span was taken into account while selecting
appropriate measurement instruments. Therefore, the tasks that are selected
require, for the most part, a non-verbal or motor response from the children.
The instruments that ask a cognitive performance are administered alternately
with tasks that do not, i.e. tasks that require children to watch movies for
example. In addition, there is no overlap between all the measurement
instruments, and all tasks measure a unique aspect with regard to answer the
research questions.

Conclusion
In summary, we are convinced that the investment that we ask from the children
and their parents is well balanced. We ask a smaller time investment from the
control group than we ask of the ASD groups and we provide benefits both
financially and in reporting back to the parents if needed. We believe that the
time and effort we ask from children and parents outweighs the potential
insights that the research can yield.