Attentional bias, inhibitory control and acute stress in current and former opiate addicts

Longitudinal behavioral and fMRI‑based assessment of inhibitory control in heroin addicts on methadone maintenance treatment

“…This is inconsistent with findings of previous studies (3,(8)(9)(10). This apparent discrepancy may reflect the fact that these previous studies were cross-sectional, whereas the present study was longitudinal, which provided a potentially more reliable assessment of the effects of MMT.…”

“…After localizer and conventional anatomical scans, GO/NO-GO blood oxygenation level-dependent (BOLD) responses were measured as a function of time using a T2*-weighted, single-shot, echo-planar imaging sequence to acquire T2*-weighted image volumes with approximate AC-PC alignment [repetition time (TR), 2,000 msec; echo time (TE), 30 msec, flip angle, 90˚]. Each brain volume consisted of 32 transverse slices with the following characteristics: Matrix, 64 tri; field of view (FOV), 256x256 mm 2 ; thickness, 4 mm; no gap; spatial resolution, 4x4x4 mm 3 . Each patient performed two GO/NO-GO task run, 168 echoplanar volumes were collected in each run, therefore a total of 336 volumes were collected for each patient.…”

“…A 6-parameter rigid-body transformation involving three rotations and three translations was used to register images and correct for head motion. Re-aligned datasets were spatially normalized to the standard stereotactic space of the Montreal Neurological Institute (MNI) using a 12-parameter affine transformation and a voxel size of 3x3x3 mm 3 . Subjects that had >1.5 mm of head translation or >1.5˚ head rotation were excluded from the analysis.…”

Attentional bias and treatment adherence in substitute-prescribed opiate users

“…Participants not using illicit opiates showed an attentional bias away from substance-related stimuli and towards neutral stimuli, relative to both participants using on top and control participants. This resonates with Constantinou et al's (2010) finding that exopiate users in rehabilitation showed a bias away from substance-related stimuli that correlated positively with their length of abstinence. It is also in keeping with a recent finding reported by Peuker and Bizarro (2014) who found attentional avoidance of smoking-related stimuli in former smokers, and with Schoenmakers et al's (2010) findings where AB away from alcohol-related stimuli induced by ABM was associated with earlier discharge from treatment for alcohol dependent inpatients.…”

“…No study to date has investigated ABM in this population. The secondary aim was based on our previous finding in a similar patient population that AB away from substance-related stimuli was positively correlated with length of abstinence in ex-opiate users (Constantinou et al, 2010). This suggestion of a link between AB and treatment progress therefore led us to also explore in the present study the relationship between AB and a key aspect of treatment adherence: whether participants were using illicit opiates on top of their prescribed opiates.…”