Bridging the bench to bedside gap: validation of a reverse-translated rodent continuous performance test using functional magnetic resonance imaging.

Vigilance, which requires attending to relevant while ignoring irrelevant stimuli, is a cognitive domain impacted by schizophrenia and bipolar disorder. Various continuous performance tests (CPT) have been used to examine neural correlates of vigilance within people with and without severe mental illness, though there are limited cross-species paradigms available. The 5-choice CPT (5C-CPT) was designed for use in rodents as a cross-species translational paradigm. Here, we evaluate construct validity of a reverse-translated human analog of the 5C-CPT in assessing the neural correlates of vigilance. Functional magnetic resonance imaging during the 5C-CPT was used to examine activation of healthy individuals during target and non-target trials separately. We found activation in brain regions implicated in sustained attention processes including premotor cortex, inferior parietal lobe, basal ganglia, and thalamus during target trials. For non-target trials, we found expected activation in inferior frontal cortex, premotor cortex, presupplementary motor area, and inferior parietal lobe. Results support the construct validity of the 5C-CPT in measuring attentional and inhibitory systems within a single task paradigm enabling the assessment of vigilance across species. This task can be used for powerful parallel human and animal investigations of the biological basis of vigilance deficits in populations with severe mental illness.

Nicotine primes attention to competing affective stimuli in the context of salient alternatives.

Despite the importance of the subject, the effects of nicotine on the interplay between affect and attentional bias are not clear. This interplay was assessed with a novel design of the Primed Attentional Competition Task (PACT). It included a 200-ms duration emotional priming picture (negative, positive, or neutral) followed by a dual-target picture of two emotional faces side-by-side. A second task included an emotional priming picture followed by a single emotional target picture in a classic affective priming (CAP) task, assessing reaction time to identify the valence. Smokers completed the tasks in a double-blind repeated measures design wearing a nicotine patch on one day and a placebo patch on the other day. Consistent with hypotheses, nicotine enhanced the effectiveness of positive primes to bias first gaze-fixations (FGFs) toward neutral pictures relative to negative pictures and attenuated the effectiveness of negative primes on FGFs toward negative pictures, but did not bias performance in the CAP task where competing target stimuli were not present. These effects of nicotine on affective priming and attentional bias toward competing reinforcers may contribute to smoking motivation.