JMIR Publications

ABSTRACT

Background:

Incentive salience processes are important for the development and maintenance of addiction. Eye-characteristics such as gaze fixation time, pupil diameter, and spontaneous blink rate (EBR) are theoretically associated with incentive salience and may serve as useful biomarkers. Yet, traditional cue-exposure paradigms used to elicit incentive salience are often constrained, potentially hindering our ability to accurately assess these markers.

Objective:

This report sought to investigate the validity of these eye-characteristics as markers of incentive salience acquired during a translatable virtual reality (VR) nicotine and tobacco product (NTP) cue-exposure paradigm.

Methods:

Non-Daily (n=33) and Daily (n=75) NTP users underwent the NTP Cue VR paradigm and completed measures of nicotine craving, NTP use history, and VR-related assessments. Eye-gaze fixation time (“attentional bias”) and pupillometry in response to NTP vs. control cues, as well as EBR during the Active and Neutral scenes, were recorded.

Results:

Greater subjective craving following Active vs. Neutral scenes was observed (F(1,106)=47.95, p<.001). Greater mean eye-gaze fixation time (F(1,106)=48.34, p<.001) and pupil diameter (F(1,102)=5.99, p=.02) in response to NTP vs. control cues were also detected. Evidence of NTP use group effects were observed in fixation time and pupillometry analyses, as well as correlations between these metrics, NTP use history, and nicotine craving. No significant associations were observed with EBR.

Conclusions:

This study provides additional evidence for attentional bias, as measured via eye-gaze fixation time, and pupillometry as useful biomarkers of incentive salience and partially supports theories suggesting the role of incentive salience diminishes as nicotine dependence severity increases.