Information Processing Modification in PTSD (Oct. 18)

Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) in Afghanistan are the
largest sustained ground operations since the Vietnam War, and the psychological effects of
combat on military personnel can be devastating. Approximately thirty percent of returning
veterans present with mental health problems. Posttraumatic stress disorder (PTSD) is the
most common problem in this group (52% of overall diagnoses). This translates into PTSD
prevalence rates of 12% in Afghani veterans and 19% for Iraqi veterans, rates that are two
to three times higher than the overall lifetime prevalence rate in the general population
(8%). Of those veterans screened positive for mental health problems 70% have not received
any mental health services. Therefore, even for individuals identified as having
psychological problems the majority are not receiving any help. Prevention and treatment of
this disorder represents one of the greatest challenges facing government officials and
health care professionals working with combat veteran populations.

PTSD often manifests after the experience of a trauma in which individuals undergo threat of
injury or death to themselves or others. The experience includes intense feelings of fear,
helplessness, and/or horror. Symptoms of this disorder are often chronic lasting for years.
Those with PTSD are likely to experience problems across several life domains including
higher rates of divorce, problems raising children, and engaging in domestic violence. They
are also more likely to suffer from other mental health problems including depression,
substance abuse, and generalized anxiety disorder. Moreover, they tend to report less life
satisfaction, experience poorer physical health, earn less money, and change jobs
frequently.

Although effective treatments do exist for PTSD, as many as 44% of individuals do not
respond to psychosocial and pharmacological treatments. Thus, there is a clear need to
develop highly effective and efficient treatments for PTSD. Researchers have established a
relationship between PTSD and difficulty disengaging attention from threat relevant
inforamtion. This knowledge; however, has not been translated into more effective treatments
for this disorder. This three-year proposal aims to test a computerized treatment for PTSD
in a double-blind, placebo-controlled study that would bridge research on attention bias and
treatment development. Those in the active condition will receive a computer-delivered
attention modification program (AMP) designed to enhance attention disengagement from
threatening stimuli. The AMP protocol includes six weeks of biweekly sessions in which
participants see 240 trials consisting of the various combinations of probe type (E or F),
probe position (top or bottom), and word type (Neutral or Trauma). Of the 240 trials, 48
include only neutral words: 2 (probe type) X 2 (probe position) X 12 (word pairs). The
remaining 192 trials include one neutral word and one trauma word: 2 (probe type) X 2 (probe
position) X 2 (repetitions) X 24 (word pairs). On trials where participants see one neutral
word and one trauma word (i.e., 80% of the trials), the probe always follows the neutral
word. Thus, although there is no specific instruction to direct attention away from threat
word, on 80% of the trials the position of the threat word indicates the position of the
probe (i.e., in the location opposite the threat word). The placebo condition (PC) will be
identical to the AMP condition except that during the presentation of threat-neutral word
pairs, the probe will appear with equal frequency in the position of threat and neutral
words. Thus, neither threat nor neutral words have signal value. We have used a very similar
training procedure to successfully establish a pattern of enhanced attention disengagement
to threat words in our pilot studies.

We present the results from 2 clinical trials demonstrating the efficacy of attention
modification programs (AMP) in ameliorating symptoms of anxiety. Specifically, we report
results from studies of individuals with generalized social phobia (GSP; n=32) and
generalized anxiety disorder (GAD; n=24) demonstrating the effectiveness of the procedures
described in this proposal. In brief, our intervention was effective in: a) changing biased
attention, b) reducing clinical symptoms of anxiety, c) maintaining its effects in up to one
year follow-up. This efficient and efficacious technique for changing attention bias in
anxiety can provide a low-cost, easy to administer treatment that is grounded in basic
cognitive science that may help reduce suffering in individuals with anxiety. The goal of
the current proposal is to extend these findings to the highly related disorder of PTSD, and
to examine the generalizability of the results to individuals with comorbid conditions. In
the current proposal we will test two hypotheses: 1) Individuals with PTSD completing the
AMP will show a larger reduction in their attention bias to threat compared to the placebo
group, 2) Individuals with PTSD completing AMP will show a larger reduction in anxiety
symptoms compared to the placebo group.

Inclusion Criteria:

- Primary DSM-IV-TR Axis I diagnosis of post-traumatic stress disorder

- Combat veteran from Iraq and/or Afghanistan

Exclusion Criteria:

- No change in medication type or dose during the twelve weeks prior to treatment

- No current psychotherapy

- No evidence of suicidal intent

- No evidence of current substance dependence in the past 6 months

- No evidence of current or past schizophrenia, bipolar disorder, or organic mental
disorder