Attentional capture by signals of reward persists following outcome devaluation

Changes of attentional bias in patients with alcohol use disorder during abstinence: A longitudinal study

BACKGROUND

Alcohol Use Disorder (AUD) is linked to an attentional bias towards alcohol-related cues (e.g. images, smells), which acquire incentive properties and promote continued consumption.

METHOD

We investigated how the general and alcohol attentional bias evolved longitudinally in AUD patients along two periods of abstinence: t = 0 (baseline, 1-3 months of abstinence) and t = 1 (follow-up; 6 months of abstinence), as well as their relationship with alcohol-related variables. General and alcohol-specific attentional bias were evaluated by the Classic and the Alcohol Stroop tests (neutral and alcohol conditions) in abstinent AUD patients and controls.

RESULTS

At t = 0, the AUD group exhibited both general and alcohol-specific attentional biases, with greater effect in the general bias. At t = 1, alcohol-specific attentional bias decreased specifically in the AUD group and reached control levels (with interference index levels increasing from 1-3 months to 6 months). However, general attentional bias showed a trend toward improvement but it did not significantly change through abstinence process (linear mixed models, controlling for age, BMI, sex and education).

CONCLUSIONS

In AUD patients, general and alcohol attentional biases exhibit different trajectories during abstinence, with the attentional bias toward alcohol improving significantly throughout this process whereas general attentional bias is maintained.

The nature of training in flavor preference learning determines the underlying associative structure

Pairing a palatable flavor (US) with an initially neutral flavor cue (CS) results in an acquired conditioned preference for the latter. Two main associations have been proposed to explain the acquisition of flavor preferences: Flavor-Flavor and Flavor-Nutrient learning. Although the hedonic reaction triggered by US consumption has also been suggested as a possible additional component underlying acquired flavor preference, this issue has received little attention. Here we explored whether the amount of training to the CS-US compound can favor the formation of a Flavor-Hedonic reaction association using rats as subjects and sucrose as the US. We expected that the more exposure to the CS-US compound, the stronger the S-R type association. Since S-R associations are not sensitive to devaluation procedures, we used a Sensory-Specific Satiety procedure to devalue the US after conditioning and then measured preferences for the CS. On Experiment 1 with a short restrictive training (classic procedure), preference for the CS was decreased after devaluation of the US compared to the control condition. On Experiment 2, with short unrestrictive training, preference for the CS was again weakened. Experiment 3 with a long unrestrictive training, rats expressed preference for the CS regardless of the devaluation procedure. These results suggest that, as with an instrumental paradigm, extensive training in flavor preference learning undermines the US devaluation effect.

Prospective Distractor Information Reduces Reward-Related Attentional Capture

Motivationally salient stimuli, such as those associated with reward, can automatically gain attentional prioritisation - even when individuals are motivated to ignore such stimuli. This 'attentional bias for reward' has often been interpreted as evidence for involuntary Pavlovian 'sign tracking' behaviour. The prioritisation of reward-signalling distractors may additionally reflect a drive to gain information about the state of the world, irrespective of the particular reward that is being signalled. In the current study we assessed whether forewarning participants on each trial as to the upcoming features of a distractor would reduce reward-related attentional capture. This manipulation reduces the information provided by the distractor, without affecting the magnitude of the signalled reward. Using eye tracking in Experiment 1, we found that reward-related attentional capture was virtually eliminated when participants were informed of the upcoming distractor colour (relative to the baseline condition when no information was provided). In Experiment 2, using a response-time version of the task, we again found a significant reduction in reward-related attentional capture when participants received information about the colour of an upcoming distractor, or information about the value of the upcoming reward. Finally, in Experiment 3 we assessed whether participants were using the pre-trial information to strategically inhibit attention to the upcoming distractor colour. The results of these experiments are discussed within the context of information-seeking accounts of reward-related attentional capture effects.

Effects of outcome revaluation on attentional prioritisation of reward-related stimuli

Stimuli associated with rewards can acquire the ability to capture our attention independently of our goals and intentions. Here, we examined whether attentional prioritisation of reward-related cues is sensitive to changes in the value of the reward itself. To this end, we incorporated an instructed outcome devaluation (Experiment 1a), "super-valuation" (Experiment 1b), or value switch (Experiment 2) into a visual search task, using eye-tracking to examine attentional prioritisation of stimuli signalling high- and low-value rewards. In Experiments 1a and 1b, we found that prioritisation of high- and low-value stimuli was insensitive to devaluation of a previously high-value outcome, and super-valuation of a previously low-value outcome, even when participants were provided with further experience of receiving that outcome. In Experiment 2, following a value-switch manipulation, we found that prioritisation of a high-value stimulus could not be overcome with knowledge of the new values of outcomes alone. Only when provided with further experience of receiving the outcomes did patterns of attentional prioritisation of high- and low-value stimuli switch, in line with the updated values of the outcomes they signalled. To reconcile these findings, we suggest that participants were motivated to engage in effortful updating of attentional control settings when there was a relative difference between reward values at test (Experiment 2) but that previous settings were allowed to persist when both outcomes had the same value at test (Experiments 1a and 1b). These findings provide a novel framework to further understand the role of cognitive control in driving reward-modulated attention and behaviour.

Cortical and subcortical substrates of minutes and days-long object value memory in humans

Obtaining valuable objects motivates many of our daily decisions. However, the neural underpinnings of object processing based on human value memory are not yet fully understood. Here, we used whole-brain functional magnetic resonance imaging (fMRI) to examine activations due to value memory as participants passively viewed objects before, minutes after, and 1-70 days following value training. Significant value memory for objects was evident in the behavioral performance, which nevertheless faded over the days following training. Minutes after training, the occipital, ventral temporal, interparietal, and frontal areas showed strong value discrimination. Days after training, activation in the frontal, temporal, and occipital regions decreased, whereas the parietal areas showed sustained activation. In addition, days-long value responses emerged in certain subcortical regions, including the caudate, ventral striatum, and thalamus. Resting-state analysis revealed that these subcortical areas were functionally connected. Furthermore, the activation in the striatal cluster was positively correlated with participants' performance in days-long value memory. These findings shed light on the neural basis of value memory in humans with implications for object habit formation and cross-species comparisons.