Brain Function and Structure in Cocaine Dependence

The Specific Aims of this project are:

Aim 1: To determine whether pretreatment brain activation on fMRI while performing a Go-Nogo
task predicts response to pharmacotherapy in cocaine dependent subjects.

Hypothesis related to Aim 1:

Pretreatment fMRI BOLD activation in cocaine dependent subjects during impulsive responding
on the Go-Nogo task predicts 8-week outcome from medication known to enhance serotonin
function (citalopram). The regression coefficient of TES on pretreatment mean BOLD activation
on the Go-Nogo task will be significantly greater for the citalopram group than the placebo
group.

Aim 2: To determine whether pretreatment brain activation on fMRI while performing an
attentional bias (cocaine Stroop) task predicts response to pharmacotherapy in cocaine
dependent subjects.

Hypothesis related to Aim 2:

Pretreatment fMRI BOLD activation in cocaine dependent subjects during cocaine related words
on the cocaine Stroop task predicts 8-week outcome from medication known to enhance serotonin
function (citalopram). The regression coefficient of TES on pretreatment mean BOLD activation
from the cocaine Stroop task will be significantly greater for the citalopram group than the
placebo group.

Inclusion Criteria:

- Male and female subjects age 18 to 50 who meet current DSM-IV criteria for cocaine
dependence who are seeking treatment.

Exclusion Criteria:

1. Current DSM-IV diagnosis of any psychoactive substance dependence other than cocaine,
marijuana, nicotine, or alcohol

2. Have a DSM-IV axis I psychiatric disorder or neurological disease or disorder
requiring ongoing treatment and/or making study participation unsafe

3. Significant current suicidal or homicidal ideation

4. Medical conditions contraindicating citalopram pharmacotherapy (liver disease, seizure
disorder, bleeding disorder, or prolonged QT interval on EKG)

5. Taking CNS active concomitant medications

6. Taking medications known to have significant drug interactions with the study
medication

7. Having conditions of probation or parole requiring reports of drug use to officers of
the court

8. Impending incarceration

9. Pregnant or breast feeding for female patients

10. Inability to read, write, or speak English

11. Having plans to leave the immediate geographical area within 3 months

12. Unwillingness or not competent to sign a written informed consent form

13. Individuals who have pacemakers, metal or electromechanical implants or metallic
foreign bodies

14. Patients who are known to be HIV positive will not be included due to possible CNS
effects of HIV.

15. Alcohol withdrawal symptoms or history of significant previous alcohol withdrawal
symptoms.