Stimulus Control

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Stimulus Control

• Jacky Maddi
• Caldwell College

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Presentation Overview

• What is a phobia?
• How people react to phobias?
• Types of phobias
• Prevalence of phobias
• Treatment options
• Review of Article
• Stimulus Fading and Differential Reinforcement
  for the Treatment of Needle Phobia in a Youth
  with Autism
• Daniel B. Shabani and Wayne W. Fisher
• Journal of Applied Behavior Analysis, 2006

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What is a phobia?

• Phobias are an exaggerated usually inexplicable
  and illogical fear of a particular object, class
  of objects, or situation.
• Defined as a medical condition in the
• DSM IV (300.29)

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How do people react to phobias?
Common phobia symptoms and sensations include
Shortness of breath or smothering sensation Palpitations, pounding heart, or accelerated heart rate Chest pain or discomfort Trembling or shaking Feeling of choking Sweating Nausea or stomach distress Feeling unsteady, dizzy, lightheaded, or faint Feelings of unreality or of being detached from yourself Fear of losing control or going crazy Fear of dying Numbness or tingling sensations Hot or cold flashes Fear of fainting
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http//www.nimh.nih.gov/health/publications/anxi
ety-disorders/complete-publication.shtmlpub6
The National Institute of Mental Health (NIMH)

• The National Institute of Mental Health (NIMH)
  estimates that 5-12 of Americans have phobias.
  This is almost 6 million Americans. Approximately
  7-9 of children have been estimated to have SP.
• The mean age of onset depends on the type of
  phobia.
• Fears and phobias are common in young children.
  Referral rates tend to increase in mid-to-late
  childhood and early adolescence.

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History

• Behaviorally, phobias manifest as the need to
  escape or avoid the feared object or situation.
• Phobias are twice as common in women as men.
• Similarly, children whose parents display a
  higher rate of specific phobia have higher rates
  themselves.

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Causes

• Numerous theories about the etiology of specific
  phobias have been offered among them are
• Learning theories
• Classic conditioning A previous neutral stimulus
  has been paired with an aversive stimulus that
  elicits a strong fear or emotional response.
• Operant conditioning Parents may inadvertently
  reinforce the phobic behavior by providing the
  child with positive or negative attention
  surrounding the avoidant behavior.

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Cognitive Models

• Cognitive models Because learning theories may
  not adequately explain the development and
  persistence of phobias, attention has been
  focused on the role of cognition.
• Children with anxiety disorders are more likely
  to display distorted and maladaptive thoughts.

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Types of Phobias

1. Animal phobias.
2. Natural environment phobias.
3. Situational phobias.
4. Blood-Injection-Injury phobia.
5. Other phobias. This includes all phobias that
   dont fall into one of the first four categories.
   Examples include fear of choking, fear of
   illness, fear of injury, fear of death, and fear
   of clowns

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Animal Type

• The fear of spiders (arachnophobia)
• and the fear of snakes (ophidiophobia)

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Natural Environment Type

• Like the fear of heights (acrophia)
• and the fear of lightning and thunderstorms
  (astraphobia)

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Situational type

• Like the fear of small confined spaces
  (claustrophbia)
• Or being "afraid of the dark," (nyctophobia).

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OTHER

• The fear of the number 13 (triskaidekaphobia),
• The fear of clowns (coulrophobia).

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Focus of the Article

• The fear of medical procedures including needles
  and injections

Belonephobia fear of needlesAichmophobia
fear of pointed objects Algophobiafear of
pain Trypanophobiafear of injections
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Diabetes

• There are 20.8 million children and adults in the
  United States, or 7 of the population, who have
  diabetes.
• http//www.diabetes.org/diabetes-statistics.jsp -
  American Diabetes Association

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Stimulus Fading and Differential Reinforcement
for the Treatment of Needle Phobia in a Youth
with Autism

• Introduction
• The purpose of the study was to treat needle
  phobia with behavior techniques,
• stimulus fading plus a DRO,
• to reduce the childs fear and to facilitate
  the treatment of a medical condition.

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Method

• Participant Oliver and 18 year old boy
  diagnosed with autism, mental retardation, and
  Type 2 diabetes.
• He attended an out patient clinic 4 days per
  week for treatment of non-compliance related to
  his diabetes.
• He had not allowed medical professionals to draw
  blood for 2 yrs.
• He had no vocal speech and communicated only
  through a few manual signs.

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Method

• Setting Sessions were conducted in a treatment
  room (3m X 3m) containing a table, chairs, and
  assorted reinforcers such as cookies.
• Generalization sessions were conducted in the
  nurses office.

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Dependent Variable

• The percentage of successful trials which was
  defined as
• Oliver not moving his hand more than 3cm during
  a 10s trial.

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IOA

• IOA was collected trial by trial during 27 of
  sessions and was always 100

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Preference AssessmentDeLeon Iwata, 1996

• Prior to each session, potential edible
  reinforcers were identified using a
  multiple-stimulus-without replacement preference
  assessment.

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Design

• An ABAB reversal design was used. The horizontal
  distance of the lancet to the tip of Olivers
  finger varied upon condition.
• The vertical distance stayed the same (8-10 cm).
• The starting distance was 61 cm away.

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Baseline

• Oliver was given a verbal and gentle physical
  prompt to place his hand on the posterboard. The
  therapist moved the lancet toward his finger.
• Immediately upon the therapists movement, Oliver
  pulled his hand away. The trial was terminated.
  Baseline trials lasted 10s or less.

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Stimulus Fading plus DRO

• Fading Step 1 Oliver had his hand on the within
  the outline on posterboard
• The lancet was horizontally positioned 61 cm from
  Olivers index finger
• If he stayed within the outline for 10s he was
  given a food item that he had chosen earlier.
• If he moved more than 3cm the trial was
  immediately terminated, all the materials were
  removed and the experimenter turned away for 10s.

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Stimulus Fading plus DRO

• Fading from each step was done after 2-3
  consecutive sessions at 100
• Step F2-F7 the distances were 46, 31, 15, 8, 5,
  1cm.
• Step F8 10 trials with the lancet 1cm above his
  index finger and an attempt to draw blood on the
  11th trial
• Step F9 attempts to draw blood were intermittent

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Results

• During baseline Oliver pulled his hand away EVERY
  time they tried to draw blood.
• All attempts to draw blood in Step F9 were
  successful. Drawing blood in the nurses station
  was also successful.

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Graph
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Generalization and Maintenance

• A two month follow-up was conducted in which
  blood draw was successful.
• Olivers mother reported that she was able to
  draw blood and measure glucose levels on a daily
  basis with no problems.

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Limitations

• 1.) An analysis of each component was not
  conducted to determine the independent
  contributions of the stimulus fading and the DRO
  components.

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Another limitationThe level of distress was not
measured during each trial

• Crying, whimpering and negative vocalizations
  appeared during baseline and at the beginning of
  treatment but were not there at the end or during
  follow-up.
• A chart like this I used with typical patients to
  rate their levels of anxiety.
• Low Anxiety119
• Medium Low Anxiety2039
• Medium Anxiety4059
• Medium High Anxiety6079
• High Anxiety80100

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Programming for Generalization based on the 9
categories of generalizationStokes Baer (1977)

• 1.) Train Hope
• There was no information on the number of
  therapists used, the setting was somewhat
  limited, and the glucose testing machine was
  always the same.

2.) Sequential Modification Behavior change did
take place in the therapy sessions and it was
generalized to the nurses station and to the home
environment. It might be useful to have trained
in other locations such as a restaurant or in the
car.
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Programming for Generalization based on the 9
categories of generalizationStokes Baer (1977)

• 3.) Introduce to naturally maintaining
  contingencies.
• I cant think of any natural contingencies
  that would maintain glucose monitoring. However,
  I would have liked Oliver to be able to test his
  blood independently.
• 4.) Train sufficient exemplars
• Not done. There was no mention of how many
  therapists were involved, if the blood taken in
  the nurses office was done by a nurse, was she
  wearing a uniform, gloves, mask? The equipment
  never changed. What if the model of the glucose
  machine became obsolete?
• 5.) Train loosely
• Nope. Could have changes the poster-board,
  or whether Oliver was sitting or standing.

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Programming for Generalization based on the 9
categories of generalizationStokes Baer (1977)

• 6.) Use indiscriminable contingencies
• Although I was pleased to see a preference
  assessment was conducted there was no mention as
  to the amount of edible reinforcer was given, a
  delay in giving the reinforcer was never
  mentioned, nor was it mentioned if Oliver ever
  became satiated during the phases that contained
  20 trials.
• 7.) Program common stimuli
• Mom or the nurse could have come into the therapy
  setting before Oliver completed the study.
  Therapists could have continued to work with
  Oliver at home before mom took over.

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Programming for Generalization based on the 9
categories of generalizationStokes Baer (1977)

• 8.) Mediate Generalization
• Due to the fact that Oliver was non-verbal
  teaching him to self-instruct may not be
  possible. Creating a activity schedule of the
  glucose monitoring procedure could be beneficial
  in helping Oliver to understand the process in
  other settings.
• 9.)Teaching generalization as a behavior
• Reinforcement in the form of edibles or activity
  could be given to Oliver if he allowed mom to
  test his blood sugar in another room in the
  house, or an outside location.

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References

• Shabani, D.B., Fisher, W.W. (2006). Stimulus
  fading and differential reinforcement for the
  treatment of needle phobia in a youth with
  autism. Journal of applied behavior analysis, 39,
  449-452.