Background and Aims Attentional bias has been demonstrated to a variety of substances. Evidence suggests that fixation time is a more direct measure of attentional bias than response time. The aims of this experiment were to demonstrate that fixation time during the visual probe task is a sensitive and stable measure of cocaine cue attentional bias in cocaine using adults compared to controls. Design A between-subject, repeated-measures experiment. Setting An outpatient research unit. Participants Fifteen cocaine using and fifteen non-cocaine-using adults recruited from the community. Measurements Participants completed a visual probe task with eye tracking and a modified Stroop during two experimental sessions. Findings A significant interaction between cue type and group (F = 13.5; P = 0.001) indicated that cocaine users, but not controls, displayed an attentional bias to cocaine-related images as measured by fixation time. There were no changes in the magnitude of attentional bias across sessions (F = 3.4; P = 0.08) and attentional bias correlated with self-reported lifetime cocaine use (r = 0.64, P = 0.01). Response time on the visual probe (F = 1.1; P = 0.3) as well as on the modified Stroop (F = 0.1; P = 0.72) failed to detect an attentional bias. Conclusions Fixation time on cocaine-related stimuli (propensity to remain focused on the stimulus) is a sensitive and stable measure of cocaine cue attentional bias in cocaine-using adults.

Background Stimuli associated with cocaine use capture attention. Evidence suggests that fixation time measured on the visual probe task is a valid measure of cocaine cue attentional bias. The aim of this experiment was to demonstrate the test-retest reliability of cocaine cue attentional bias as measured by fixation time during the visual probe task. Methods In a within-subject, repeated-measures design, thirty-six non-treatment seeking cocaine-using adults completed a visual probe task with eye tracking. Results Participants displayed an attentional bias to cocaine-related images as measured by fixation time across two occasions (F (1, 35) = 56.5, p < 0.0001). A Pearson correlation indicated significant test-retest reliability for this effect (r = 0.51, p = 0.001). Response time failed to detect an attentional bias and test-retest reliability was low (r = 0.24, p = 0.16). Conclusion Fixation time during the visual probe task is a reliable measure of cocaine cue attentional bias in cocaine-using adults across time.

Background Cocaine users show impaired inhibitory control on cued go/no-go tasks and attention bias to drug-related images in eye-tracking tasks. The results of a previous study suggested that there is a relationship between inhibitory control and attention bias in alcohol drinkers such that the presentation of alcohol-related images as a go cue in a cued go/no-go task significantly impaired inhibitory control compared to neutral images as a go cue. The present study determined the generality of these previous findings by assessing inhibitory control in cocaine users utilizing a modified cued go/no-go task with cocaine or neutral images as the cues. Methods Non-treatment seeking cocaine users (N=30) completed the modified task after completing detailed measures of demographics and drug use. Participants were matched on basic demographic factors and were assigned to groups in which they saw either a cocaine or neutral image as the go cue. Results Participants assigned to the cocaine image go cue condition had a significantly higher proportion of inhibitory failures to the no-go target than their counterparts assigned to the neutral cue condition, but there were no group differences on reaction time (i.e., accuracy was not traded for speed). Conclusions Cocaine users were less able to inhibit pre-potent responses when a cocaine-related image served as the go cue than when a neutral image served as the go cue, consistent with previous research in alcohol users. The outcomes suggest that cocaine-related cues produce disinhibition, perhaps contributing to the high incidence of relapse or continued cocaine use.

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The visual probe task with eye tracking is a sensitive measure of cocaine and alcohol cue attentional bias. Despite the high comorbidity between cocaine and alcohol dependence, attentional bias studies have examined the influence of cocaine and alcohol-related cues separately. The aim of this experiment was to directly compare the magnitude of cocaine and alcohol cue attentional bias in individuals dependent on cocaine or cocaine and alcohol. Individuals who met criteria for cocaine dependence (n=20) or both cocaine and alcohol dependence (n=20) completed a visual probe task with eye tracking. Cocaine-dependent participants displayed an attentional bias towards cocaine, but not alcohol. In contrast, cocaine-alcohol dependent participants displayed an attentional bias to both cocaine and alcohol, and the magnitude of these biases did not differ. The magnitude of cocaine cue attentional bias, however, was significantly smaller in the cocaine-alcohol dependent group compared to the cocaine-dependent group. These results suggest that fixation time during the visual probe task is sensitive to clinically relevant differences in substance use disorders. The incentive value of cocaine-related cues, however, may differ for individuals who are also dependent on alcohol.