Motivational and control mechanisms underlying adolescent versus adult alcohol use

Increased motivation towards alcohol use and suboptimal behavioral control are suggested to predispose adolescents to alcohol use disorders (AUDs). Paradoxically however, most adolescent AUDs resolve over time without any formal intervention, suggesting adolescent resilience to AUDs. Importantly, studies directly comparing adolescent and adult alcohol use are largely missing. We therefore aimed to unravel the moderating role of age in the relation between alcohol use and motivational and control-related cognitive processes in 45 adolescent drinkers compared to 45 adults. We found that enhancement drinking motives and impulsivity related positively to alcohol use. Although enhancement drinking motives and impulsivity were higher in adolescents, the strength of the relation between these measures and alcohol use did not differ between age groups. None of the alcohol use-related motivational measures (i.e., craving, attentional bias, and approach bias) and behavioral control measures (i.e., interference control, risky decision making, and working-memory) were associated with alcohol use or differed between age groups. These findings support the role of impulsivity and affective sensitivity in adolescent drinking but question the moderating role of age therein. The current study contributes towards understanding the role of age in the relation between alcohol use and cognition

Grasping preparation enhances orientation change detection

Contains fulltext : 130275.pdf (publisher's version ) (Open Access)Preparing a goal directed movement often requires detailed analysis of our environment. When picking up an object, its orientation, size and relative distance are relevant parameters when preparing a successful grasp. It would therefore be beneficial if the motor system is able to influence early perception such that information processing needs for action control are met at the earliest possible stage. However, only a few studies reported (indirect) evidence for action-induced visual perception improvements. We therefore aimed to provide direct evidence for a feature-specific perceptual modulation during the planning phase of a grasping action. Human subjects were instructed to either grasp or point to a bar while simultaneously performing an orientation discrimination task. The bar could slightly change its orientation during grasping preparation. By analyzing discrimination response probabilities, we found increased perceptual sensitivity to orientation changes when subjects were instructed to grasp the bar, rather than point to it. As a control experiment, the same experiment was repeated using bar luminance changes, a feature that is not relevant for either grasping or pointing. Here, no differences in visual sensitivity between grasping and pointing were found. The present results constitute first direct evidence for increased perceptual sensitivity to a visual feature that is relevant for a certain skeletomotor act during the movement preparation phase. We speculate that such action-induced perception improvements are controlled by neuronal feedback mechanisms from cortical motor planning areas to early visual cortex, similar to what was recently established for spatial perception improvements shortly before eye movements.8 p

Resting-state theta/beta EEG ratio is associated with reward- and punishment-related reversal learning

Contains fulltext : 175357.pdf (publisher's version ) (Open Access)Prior research has shown that the ratio between resting-state theta (4-7 Hz)-beta (13-30 Hz) oscillations in the electroencephalogram (EEG) is associated with reward- and punishment-related feedback learning and risky decision making. However, it remains unclear whether the theta/beta EEG ratio is also an electrophysiological index for poorer behavioral adaptation when reward and punishment contingencies change over time. The aim of the present study was to investigate whether resting-state theta (4-7 Hz)-beta (13-30 Hz) EEG ratio correlated with reversal learning. A 4-min resting-state EEG was recorded and a gambling task with changing reward-punishment contingencies was administered in 128 healthy volunteers. Results showed an inverse relationship between theta/beta EEG ratio and reversal learning. Our findings replicate and extend previous findings by showing that higher midfrontal theta/beta EEG ratios are associated with poorer reversal learning and behavioral adaptive responses under changing environmental demands.10 p

Stroop interference and the timing of selective response activation.

Contains fulltext : 70952.pdf (publisher's version ) (Closed access)OBJECTIVE: To examine the exact timing of selective response activation in a manual color-word Stroop task. METHODS: Healthy individuals performed two versions of a manual color-word Stroop task, varying in the probability of incongruent color-words, while EEG was recorded. RESULTS: Stroop interference effect was manifested as longer reaction times for incongruent relative to congruent color-words, and was larger in a task version where incongruent color-words were presented less frequently. Whereas the congruence between color display and word meaning did not affect average stimulus- and response-locked lateralized readiness potential (LRP) onset latencies nor response-locked LRP amplitudes, P3 peak latencies were longer and stimulus-locked LRPs were smaller for incongruent than congruent trials. CONCLUSIONS: These data are consistent with the idea that behavioral Stroop interference reflects delays in processing stages preceding color-based selective response activation in a subset of trials. They also do not exclude additional delays after color-based selective response activation, at least up until some 200ms before the overt response. SIGNIFICANCE: This chronometric analysis allows for a parcellation of the Stroop interference process that may be applied in psychopathology