Retraining approach bias in forensic sexual offenders and sexual addicts

Within the forensic health services there is demand for objective assessment
tools. In this study we test an instrument designed to measure approach bias
towards sexual stimuli. It is hypothesized that we will find an approach bias
among sexual offenders in forensic health care and among those with a sex
addiction. Secondly in this project, an intervention designed to reduce
approach bias will be tested. It is hypothesized that the intervention, in
comparison to the placebo intervention, will lead to a greater reduction in
approach bias among both sexual offenders in the forensic healthcare and sex
addicts receiving standard addiction treatment.

The main objective of this study is the measurement of approach bias in sex
offenders and sex addicts, alongside determining whether the approach bias for
sexual stimuli differs between these groups. A further objective is to test an
intervention designed to train away the approach bias in sex addicts
(*avoidance training*), among both those receiving forensic health care and
addiction treatment. Secondary objectives are testing whether the training
reduces sexual preoccupation and sexual behaviors and testing whether these
reductions are related to a reduction in approach bias.

The study consists of two parts: A. and observational study, and B. an
experimental, double-blind, placebo-controlled study.

The intervention is a computerized training, the so-called *avoidance
training*. In the training, approach bias for sexual stimulus is trained away.
The training consists of six sessions spread over a period of three weeks.
During each session the participants complete a training of approximately 20
minutes. The training is a computer task in which the participants see sexual
images and control images (nature photographs; landscapes, seas, flowers,
etc.). The images are tilted either 5 degrees to the left or to the right. The
one half of the participants (from the intervention condition and from the
control condition) receives the instructions to push images that are tilting to
the left away from themselves by pressing a button on the keyboard (by doing so
the image gets smaller, creating the illusion that it is moving away from the
participant), and to pull images that are tilted to the right towards
themselves (the image gets larger in this case). For the other half of the
participants the instructions are reversed. The images that the participants in
the intervention condition push away from themselves are the sexual images
while the images they pull towards themselves are the nature images. In the
control condition, half of the sexual images and the half of the nature images
are to be pulled towards the participant, the other half are to be pushed away.

It is expected that the consistent pushing away of the sexual stimuli will lead
to a reduction in approach bias and thus faster avoidance of the images. In the
control group no changes is expected in the approach bias.

There are no safety risks associated with carrying out the computer tasks. In
the case of a participant experiencing the procedure as too much of a burden,
he or she is permitted to prematurely end his or her participation. The
training consists of 9 sessions, 2 of which are in the clinic and 7 of which
are done at home. The first and last sessions both take 45 minutes to complete
and the other 7 sessions last about 20 minutes. Comparable interventions for
substance abuse showed diverse effects among patients and healthy groups;
behavioral effects were stronger among patients than among healthier groups. It
is for that reason that the intervention is specifically being tested among
patients.