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Background: As for many psychotherapies, there is ongoing discussion about the role of specific versus unspecific mechanisms in the effectiveness of Eye-Movement and Desensitization Reprocessing (EMDR) therapy for post-traumatic stress disorder. However, research directly examining the potential role of non-specific mechanisms in EMDR is scarce. Objectives: Here, we address the role of one non-specific factor that is often put forward, namely treatment effectiveness expectations, in a laboratory model of EMDR therapy. Method: In a lab-based study (N = 96) and an online study (N = 173), we gave participants verbal instructions to manipulate their treatment expectations. Instructions emphasized EMDR’s effectiveness or infectiveness. Then, participants were asked to recollect an unpleasant autobiographical memory with or without making eye-movements. Results: In line with previous studies, we found significant reductions of reported vividness and emotionality of negative autobiographical memories. However, this effect was not modulated by manipulated treatment efficacy expectations. It must be noted that manipulation checks indicated that it was difficult to influence treatment effectiveness expectations using verbal suggestions. Conclusions: These findings corroborate the results of two earlier reports, suggesting that the role of treatment expectations in EMDR therapy may be limited.

Background and objectives Simultaneously making eye movements and recalling a memory leads to competition in working memory (WM), which reduces memory vividness and emotionality. The dose-response relationship between WM taxation and aversive memory degradation is predicted to be either linear (i.e., more cognitively demanding tasks exhibit stronger effects) or follow an inverted U-curve (i.e., there should not be too little, but also not too much taxation). Methods Participants (N = 44) recalled four aversive autobiographical memories under four conditions that differed in WM taxation: complex, intermediate, simple, or no counting. Before and after each intervention, and at 24 h follow-up, participants recalled the aversive memory and rated it on vividness and unpleasantness. Using a Bayesian approach the linear and inverted U-shape relationships were directly compared. Results Pretest to posttest drops in vividness and unpleasantness became larger with increased WM taxation of the counting conditions. There was no support for either hypotheses from pretest to follow-up for memory unpleasantness, whereas for memory vividness anecdotal evidence was found for a linear relationship. Limitations A reaction time (RT) task was used to select counting tasks of varying difficulties. However, the validity of this task appears to be compromised under very strenuous conditions. Higher levels of WM taxation might have been possible with more difficult counting tasks. Conclusions There is strong evidence for a linear dose-response relationship between WM taxation and memory degradation immediately after the intervention, and some unconvincing evidence for this pattern one day later. There was no evidence for an inverted U-curve.

Substance-dependent individuals have been shown to display increased P3 amplitudes in response to substance-related stimuli. The P3 component of the event-related potential (ERP) has been associated with ‘motivated attention’ for substance cues. Enhanced processing of substance cues has not been unequivocally demonstrated in alcohol-dependent patients. The main goal of the present study was to further investigate electrophysiological processing of alcohol and non-alcohol (soft drink) cues in alcohol-dependent patients and controls. In addition, it was examined whether groups differed in the processing of positive emotional cues. Results showed that alcohol-dependent patients did not respond with more enlarged P3 amplitudes to alcohol cues than soft drink cues. At fronto-central sites they even showed reduced alcohol cue-elicited P3 amplitudes as compared to controls. These results are in line with results from studies using behavioral measures of cognitive processing and might be explained by the use of avoidance strategies, i.e., patients' effort to remain abstinent or control their alcohol use. There were no differences between groups regarding the processing of positive cues. Interpretations and implications of the findings are discussed.

Excessive computer gaming has recently been proposed as a possible pathological illness. However, research on this topic is still in its infancy and underlying neurobiological mechanisms have not yet been identified. The determination of underlying mechanisms of excessive gaming might be useful for the identification of those at risk, a better understanding of the behavior and the development of interventions. Excessive gaming has been often compared with pathological gambling and substance use disorder. Both disorders are characterized by high levels of impulsivity, which incorporates deficits in error processing and response inhibition. The present study aimed to investigate error processing and response inhibition in excessive gamers and controls using a Go/NoGo paradigm combined with event-related potential recordings. Results indicated that excessive gamers show reduced error-related negativity amplitudes in response to incorrect trials relative to correct trials, implying poor error processing in this population. Furthermore, excessive gamers display higher levels of self-reported impulsivity as well as more impulsive responding as reflected by less behavioral inhibition on the Go/NoGo task. The present study indicates that excessive gaming partly parallels impulse control and substance use disorders regarding impulsivity measured on the self-reported, behavioral and electrophysiological level. Although the present study does not allow drawing firm conclusions on causality, it might be that trait impulsivity, poor error processing and diminished behavioral response inhibition underlie the excessive gaming patterns observed in certain individuals. They might be less sensitive to negative consequences of gaming and therefore continue their behavior despite adverse consequences.

Several studies indicate that individuals with substance use disorders (SUD) exhibit biases in the cognitive processing of substance-related stimuli. These biases facilitate the detection of substance cues and have been argued to play a causal or perpetuating role in addiction. Two electrophysiological indices of cognitive processing, the P300 and Slow Potential (SP) components of the event-related potential (ERP), are associated with the deployment of attentional resources to motivationally relevant stimuli. In the present meta-analysis P300 (300-800ms) and SP (>800ms) amplitudes are used to investigate whether SUD persons show enhanced cognitive processing of substance cues relative to neutral cues as opposed to control participants. Results indicated the P300 and SP amplitude effect sizes were significantly larger in SUD participants than controls. This result is explained by substance users' motivated attention. Additional stratified moderator analyses revealed that both P300 and SP amplitudes were not moderated by electrode site (Fz vs. Pz), type of substance used (stimulants vs. depressants), substance use status (abstinent vs. non-abstinent), age, gender and task requirements (active vs. passive paradigms).

textabstractIntroduction: The role of inhibitory control in addictive behaviors is highlighted in several models of addictive behaviors. Although reduced inhibitory control has been observed in addictive behaviors, it is inconclusive whether this is evident in smokers. Furthermore, it has been proposed that drug abuse individuals with poor response inhibition may experience greater difficulties not consuming substances in the presence of drug cues. The major aim of the current study was to provide electrophysiological evidence for reduced inhibitory control in smokers and to investigate whether this is more pronounced during smoking cue exposure. Methods: Participants (19 smokers and 20 non-smoking controls) performed a smoking Go/NoGo task. Behavioral accuracy and amplitudes of the N2 and P3 event-related potential (ERP), both reflecting aspects of response inhibition, were the main variables of interest. Results: Reduced NoGo N2 amplitudes in smokers relative to controls were accompanied by decreased task performance, whereas no differences between groups were found in P3 amplitudes. This was found to represent a general lack of inhibition in smokers, and not dependent on the presence of smoking cues. Conclusions: The current results suggest that smokers have difficulties with response inhibition, which is an important finding that eventually can be implemented in smoking cessation programs. More research is needed to clarify the exact role of cue exposure on response inhibition.

Substance use disorders are characterized by cognitive processing biases, such as automatically detecting and orienting attention towards drug-related stimuli. However, it is unclear how, when and what kind of attention (i.e. implicit, explicit) interacts with the processing of these stimuli. In addition, it is unclear whether smokers are hypersensitive to emotionally significant cues in general or to smoking-related cues in particular. The present event-related potential study aimed to enhance insight in drug-related processing biases by manipulating attention for smoking and other motivationally relevant (emotional) cues in smokers and non-smokers using a visual oddball task. Each of the stimulus categories served as a target (explicit attention; counting) or as a non-target (implicit attention; oddball) category. Compared with non-smokers, smokers’ P300 (350–600 ms) was enhanced to smoking pictures under both attentional conditions. P300 amplitude did not differ between groups in response to positive, negative, and neutral cues. It can be concluded from this study that attention manipulation affects the P300 differently in smokers and non-smokers. Smokers display a specific bias to smoking-related cues, and this bias is present during both explicit and implicit attentional processing. Overall, it can be concluded that both explicit and implicit attentional processes appear to play an important role in drug-related processing bias.

Aims: To investigate the changes in the electroencephalographic (EEG) spectrum in smokers during exposure to a neutral and a smoking-related cue to determine whether these EEG changes are still present in ex-smokers after prolonged abstinence and to examine the relationship between the power in each spectral bandwidth and subjective craving. Methods: EEG frequencies in response to a smoking-related and a neutral cue were examined in 23 smokers and 21 ex-smokers, who quit smoking for 1.4 years on average. Additionally, self-report measures of cigarette craving and nicotine dependence were obtained. The spectral power of each bandwidth was computed, log-transformed, and analyzed using a within-subject design. Differences between EEG activity under neutral and smoking conditions were correlated with differences between pre- and postexperimental subjective craving. Results: Increases in reward craving (desire and intention to smoke) were associated with reduced theta activity, whereas increases in withdrawal craving (reduction of negative affect and withdrawal symptoms) were correlated with increases in both delta and higher alpha power. Furthermore, in smokers, but not in ex-smokers, a significant beta power increase was observed between the neutral condition and the smoking condition. Conclusion: Since the beta band is associated with arousal, attention, and alertness, it is suggested that the beta increase in response to the smoking cue might reflect an enhanced allocation of resources to smoking-related stimuli, i.e. a processing bias, which is an important feature of substance abuse. Since ex-smokers do not respond to the smoking cue with beta activity enhancement, we preliminarily conclude that smoking cues do not arouse ex-smokers or capture their attention as much as they do in smokers.

Processing bias is an important feature of substance abuse. The issue whether processing bias is a more or less permanent feature of nicotine addiction remains to be resolved. The present study addresses the role of smoking status on smoking-related processing bias. We employed Event-Related Brain Potentials (ERPs) as measure of processing bias to investigate this issue. Further, self-report measures of nicotine craving and pleasantness ratings of smoking stimuli were obtained. Three groups, smokers, ex-smokers and never-smokers, were compared on their electrophysiological brain response to smoking-related and neutral pictures. The present study shows that both the P300 and SPW amplitudes in response to smoking-related pictures are significantly more enhanced for smokers than for ex-smokers and never-smokers at frontal and central sites, whereas the magnitude of the P300 and SPW amplitudes in response to neutral pictures does not differ between the three groups. Accordingly, it can be concluded that smokers show more bias for smoking-related pictures than ex-smokers and smokers. Because there is no significant difference between the P300 and SPW amplitudes of ex-smokers and never-smokers, it can also be concluded that ex-smokers display the same (low) level of processing bias as never-smokers. In addition, nicotine-craving ratings and pleasantness ratings of smoking stimuli were higher in smokers compared to ex-smokers. It can be concluded that the smoking-related craving, pleasantness rating, and processing bias decreases after a period of prolonged abstinence.

This study examined relations between memories for childhood teasing and symptoms of social anxiety, depression, and eating disorders in 130 Dutch adolescents. Participants completed the Teasing Questionnaire-Revised which measures how much people recall having been teased during childhood, as well as the Social Anxiety Scale for Children, the Child Depression Inventory, and the Children's Eating Attitude Test. Analysis yielded significant positive correlations between self-reported recollections of childhood teasing and various symptoms. Furthermore, some evidence indicated specific domains of teasing were associated with specific types of psychopathological symptoms.

Background Classical conditioning has been suggested to play an important role in the development, maintenance, and relapse of tobacco smoking. Several studies have shown that initially neutral stimuli that are directly paired with smoking are able to elicit conditioned responses. However, there have been few human studies that demonstrate the contribution of higher-order conditioning to smoking addiction, although it is assumed that higher-order conditioning predominates learning in the outside world. In the present study a higher-order conditioning task was designed in which brain responses of smokers and non-smokers were conditioned by pairing smoking-related and neutral stimuli (CS1smoke and CS1neutral) with two geometrical figures (CS2smoke and CS2neutral). ERPs were recorded to all CSs. Results Data showed that the geometrical figure that was paired with smoking stimuli elicited significantly larger P2 and P3 waves than the geometrical figure that was paired with neutral stimuli. During the first half of the experiment this effect was only present in smokers whereas non-smokers displayed no significant differences between both stimuli, indicating that neutral cues paired with motivationally relevant smoking-related stimuli gain more motivational significance even though they were never paired directly with smoking. These conclusions are underscored by self-reported evidence of enhanced second-order conditioning in smokers. Conclusions It can be concluded that smokers show associative learning for higher-order smoking-related stimuli. The present study directly shows the contribution of higher-order conditioning to smoking addiction and is the first to reveal its electrophysiological correlates. Although results are preliminary, they may help in understanding the etiology of smoking addiction and its persistence.