JFC's notes for lecture 17

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Design of Health Technologies
lecture 17
John Canny
11/07/05
IT for Mental Health
Q: Why computer therapy?
A: Many cases of depression and anxiety disorders go
untreated – patients are ashamed to seek help, and may
fear the consequences at work and home.
A: Therapy is expensive and beyond the reach of many
patients.
Computer therapy is very cheap and available by
comparison. It looks like a good option, as long as it
works…
Marks et al.

CBT (Cognitive Behavior Therapy)
via Computer.

What is CBT?

CBT is a method used to treat depression and anxiety
via a recognition of “distorted thinking,” and
“cognitive restructuring.” It may also involve
classical conditioning when used to treat Obsessive
Compulsive Disorder.
Marks et al.
Considered 4 systems, which patients were advised to use
at least 6 times over 12 weeks:
 Fearfighter: for phobia/panic

Cope: for depression/anxiety

Balance: for general anxiety/depression

BTSteps: for Obsessive Compulsive Disorder
Patients had some direct contact with therapists for advice,
and help with the system.
Marks et al.
Fearfighter: was PC or web-based.
Cope and BTSteps: were phone-based. The system used
voice, while users responded with phone key presses.
Balance: was PC-based using a CD-Rom.
Marks et al. Outcomes
Improvements were found in all groups.
Typical improvements were 20-40% in standard measures
of anxiety or depression.
Significances were not high, and there was a large variation
in difference (meaning some patients reported getting
worse).
Nevertheless, this kind of treatment seems to have worked
well.
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VR and Phobias (North et al.)

VR therapy via SD (Systematic Desensitization) is
becoming very popular.

SD is a process of gradually introducing a disturbing
stimulus (e.g. view from a high place) in otherwise
pleasant surroundings.

This process gradually
suppresses the anxiety response.
VR and Phobias
VR for SD has several advantages:

Patients often have difficulty imagining the stimulus
themselves.

They are often afraid of experiencing it directly – which
may also be expensive and time-consuming.

VR affords patient privacy and confidentiality during
treatment.
VR and Phobias
Several case studies reported in the North paper:

Aerophobia (flying) two subjects reported
improvements

Agoraphobia (described as a fear of situations from
which it is difficult to escape) study with 60 patients,
showed strong improvement in the treatment group.

Acrophobia (heights) with 20 college students, strong
improvement in the treatment group.
VR and Phobias
Physiological signs in patients undergoing VR therapy
typically mirrored real reactions –
Anxiety, muscle tension, palpitations, shaking, sweating
and dizziness.
VR and Phobias
A very high degree of realism did not seem to be
necessary for effective VR therapy.
Most environments had simple graphics, limited sound and
vibration effects (and no G-forces apparently).
Subjects sense of presence in the virtual
world increased spontaneously with
repeated treatments.
This generally follows the therapeutic trend.
VR and imagination (Vincelli et al.)
Imagination and memory play a central role in classical
therapy.
 Most psychotherapy is based on the analysis and
modification of mental images.
 Many anxiety disorders result from the maintenance of
oppressive images (Beck).
 Imagined stimuli elicit most of the physiological
responses of real stimuli: pulse, pupil size, muscle
tension, blood glucose, skin temperature,…
 Penfield (1963) showed that imaginative stimuli arise in
areas of cortex devoted to sensory perception.

VR and imagination
Some specific therapies using imagination include:
 “Projection in time” – rationally reconstructing the future

“De-catastrophizing an image” –
modifying a disturbing image

“Image modeling and substitution” –
interrupting a negative train of images

“Covert conditioning” – subtle conditioning using
imagined rather than real stimuli
VR and imagination - SD
Systematic Desensitization (SD) is one of the more popular
approaches in VR therapy.
SD consists of placing the patient in a pleasant state, and
then introducing an anxiety-provoking stimulus. As this
process is repeated the anxiety response is inhibited.
Limitations of VR therapy - Milton
Acknowledges successes in many areas:
 Phobias
 Body Image, eating disorders, sexual dysfunction,
treating autism.

But there are some major limitations to more
widespread use.
Limitations of VR therapy
Cost of building models:
Virtual worlds require some kind of 3D CAD system. These
tools are notoriously hard to use.
Detail is needed not only in visual appearance, but also in
their physics (objects should behave normally if the
user picks them up).
Human models (avatars) can be enormously complex, but
are mostly rigid manequins.
Limitations of VR therapy
Cost of rendering environment:
The original systems used a CAVE, and array of screens
with 3d input devices, and costs running into millions.
More recently, stereoscopic displays and 3D mice are
available at low cost. But the level of “immersion” is
much lower.
Limitations of VR therapy
Limitations of Study methods:
Many studies of VR methods have not used careful enough
criteria for defining the condition under study –
acrophobia, aerophobia. Most often patients self-submit
to the experiment or are referred because of existing
treatment.
Tools such as DSM-IV could be used to more carefully
chart the condition in the patients who participate in
studies.
HutchWorld (not in readings)

Hutchworld is a virtual community attached to the
Hutchison Cancer Research Center.

Designed to provide social
support for cancer patients
and their families.

Based on Microsoft’s
Vworld’s system.
HutchWorld

Built on an earlier system called CHESS (Comprehensive
Health Enhancement Support System) that provide
information for chronically ill patients, esp. those with
HIV.

Researchers found that CHESS users used the system
more than once per day. They also found that users
made heavier use of the social support functions of the
site, more than the informational functions.
HutchWorld – Design Guidelines

Recreating the actual building was more effective than
an abstract environment.

Access was restricted to patients, caregivers and their
families.

Information was restricted to “public”
information, not sensitive or
specialized medical information.
HutchWorld – Design Evolution

The 3D Vworlds version had some serious shortcomings:

It was difficult to achieve a critical mass of users and
the space often appeared empty.

Users could not “lurk” in the space since their avatar
was visible if they were there.

Users did not return after a negative first experience.
HutchWorld – Design Evolution

The second prototype was designed to support
asynchronous communication.

This allowed patients to check in when they wanted to –
many patients were awake in the early hours of the
morning. The Hutchworld system provided a social
channel even if no-one else was online.

“Information portal” functions were integrated in the
system so users could do much more than message.
They still had a visible avatar while visiting the site.
HutchWorld – Design Evolution

The second prototype was designed to support
asynchronous communication.

This allowed patients to check in when they wanted to –
many patients were awake in the early hours of the
morning. The Hutchworld system provided a social
channel even if no-one else was online.

“Information portal” functions were integrated in the
system so users could do much more than message.
They still had a visible avatar while visiting the site.
Discussion Questions
Mental health is an important topic in itself, but also
interacts with other medical therapies (e.g. as in
Hutchworld and CHESS).

Discuss ways of integrating mental health support with
other health care delivery systems.

A lot of research is directed at “high-end” (VR)
therapies, but several successful systems were much
simpler. Discuss means of deploying “low-end” computer
therapies, and what kinds of conditions might be treated
with them.
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