Is irregular time estimation a common factor in smoking behavior and delay discounting?

INTRODUCTION: Smoking is known to be associated with steeper delay discounting which is a widely used measure of externalizing behavior. This study investigates individual aspects of time estimation and the extent to which these are associated with differences in delay discounting and smoking behavior. METHODS: The study was conducted as an online experiment in a sample of undergraduate students (N = 495), including 51 smokers. Participants completed a serial time estimation, delay discounting task (MCQ), BIS/BAS questionnaire, Fagerstrom test for nicotine dependence and an alcohol use assessment (QFV). RESULTS: Smoking, heavy drinking and delay discounting were associated with faster estimation of time. Furthermore, smoking and delay discounting were associated with differences in autocorrelation. Fun seeking was associated with smoking and alcohol use, but not with time estimation or delay discounting. CONCLUSIONS: This study provides evidence for the hypothesis that an acceleration of the internal clock might lead to time over-estimation which could lead towards delayed consequence sensitivity and addiction. The study also found further evidence for the hypothesis that distortions in time estimation (i.e., autocorrelation) may be related to delay discounting and smoking. Smoking and delay discounting were associated with faster estimations of time and differences in autocorrelation.

Prefrontal tDCS attenuates counterfactual thinking in female individuals prone to self-critical rumination.

The tendency to ruminate (i.e., repetitive negative self-referential thoughts that perpetuate depressive mood) is associated with (a) an elevated propensity to maladaptively experience counterfactual thinking (CFT) and regret, and (b) hypo-activity of the left dorsolateral prefrontal cortex (DLPFC). The goal of this study was to investigate whether anodal transcranial direct current stimulation (tDCS) over the left DLPFC, in function of self-critical rumination tendencies, momentarily reduces counterfactual thinking and regret (assessed via self-report and psychophysiological indices). Eighty healthy participants with different levels of self-critical rumination received either anodal or sham tDCS while performing a decision making task in which they were repeatedly confronted with optimal, suboptimal, and non-optimal choice outcomes. The results showed that among rumination-prone individuals, anodal (versus sham) tDCS was associated with decreased CFT and attenuated psychophysiological reactivity to the differential choice outcomes. Conversely, among low rumination-prone individuals, anodal (versus sham) tDCS was associated with increased CFT and regret, but in absence of any effects on psychophysiological reactivity. Potential working mechanisms for these differential tDCS effects are discussed. Taken together, these results provide initial converging evidence for the adaptive effects of left prefrontal tDCS on CFT and regret to personal choice outcomes among individuals prone to engage in self-critical rumination.

Acetaminophen does not affect cardiac and brain responses to social rejection but seems to attenuate behavioral adaptation in a social judgment task.

The present study examined the effect of Acetaminophen on the painful experience of social rejection by examining brain, cardiac and behavioral measures reflecting different aspects of social feedback processing. Healthy students (N = 72), after ingesting either Acetaminophen or a placebo, performed a social judgment paradigm (SJP), in which they could be expectedly or unexpectedly rejected or accepted. During the task, cardiac and brain responses to different types of feedback were measured, as well as expectancies relating to the given feedback. Enhanced cardiac deceleration was found after unexpected social rejection as compared to all other conditions. Larger mean P3 amplitude was found after expected positive and negative feedback stimuli as compared to unexpected stimuli. While cardiac deceleration and P3 were not affected by Acetaminophen, behavioral responses were. While in the control group the percentage of acceptance predictions decreased over the experiment (learning from negative feedback), the Acetaminophen group did not adjust their positive prediction bias over time. The unexpected effect of Acetaminophen on prediction behavior suggests that Acetaminophen might indeed play a role in social pain perception. The normally observed social pain-based learning effect seems to disappear when participants ingest Acetaminophen, which can be interpreted as a reduced pain perception after Acetaminophen.

Multi-session electrical neuromodulation effects on craving, relapse and cognitive functions in cocaine use disorder: A randomized, sham-controlled tDCS study.

BACKGROUND: The use of transcranial Direct Current Stimulation (tDCS) has previously shown promising results for reducing craving in cocaine use disorder. In this study we further explored the potential of tDCS as add-on intervention in the treatment of cocaine use disorder. METHODS: In a randomized, placebo-controlled, between subject study, we applied tDCS bilaterally with the anodal electrode targeting the right dorsolateral prefrontal cortex (DLPFC; https://clinicaltrials.gov/ct2/show/NCT03025321). Patients with cocaine use disorder were allocated to ten sessions of either active tDCS (n = 29) or sham (n = 30) on five consecutive days. Inhibitory control and risky decision-making were measured via a Go-NoGo task and a two-choice gambling task, respectively, each at baseline, one day after all tDCS sessions and after three months. Relapse at follow-up and craving were also assessed. RESULTS: There was no significant effect of active tDCS on the number of cocaine use days and craving. Relapse was frequent among patients who had received either active or sham tDCS (48.0 % and 69.2 %, respectively), despite an overall decrease in craving during the first two weeks of treatment. No effects were found on cognitive functions. An exploratory analysis for crack cocaine use only revealed that relapse rates were significantly reduced after active tDCS (n = 17) as compared to sham (n = 19). CONCLUSIONS: No beneficial effects of tDCS on number of cocaine use days, craving and cognitive functions were found in the present study, but somewhat promising results were obtained regarding relapse rates among crack-cocaine users specifically. Further research is required to determine the efficacy of tDCS as a complementary treatment in cocaine use disorder.

Long-term tDCS effects on neurophysiological measures of cognitive control in tobacco smokers.

INTRODUCTION: In this study we assessed the effects of transcranial Direct Current Stimulation (tDCS) on inhibitory control and error processing as measures of cognitive control to better understand tDCS modulation of smoking behaviour. METHODS: Smokers were allocated to six sessions of either active tDCS (n = 34) or sham tDCS (n = 35) (https://clinicaltrials.gov/ct2/show/NCT03027687). Immediately before, one day after, and three months after all tDCS sessions, participants performed the Go-NoGo task while we measured behavioural and neurophysiological responses. RESULTS: One day after the intervention no significant effect was found of active tDCS on behavioural and neurophysiological measures of cognitive control in tobacco smokers. However, a significant improvement in reaction times, and a decrease in No-Go P3 amplitudes for smoking cues was found three months after active tDCS. CONCLUSION: Given the direction of the effect, we speculate that tDCS has a long-term modulatory learning effect on selective attention and motor inhibition.

No effect of repetitive tDCS on daily smoking behaviour in light smokers: A placebo controlled EMA study.

INTRODUCTION: The effectiveness of repetitive transcranial Direct Current Stimulation (tDCS) on reducing smoking behaviour has been studied with mixed results. Smoking behaviour is influenced by affect and context, therefore we choose to use mobile ecological momentary assessments (EMA) to measure changes in smoking behaviour after tDCS. METHODS: In a randomized, placebo-controlled, between subject study, we applied tDCS bilaterally with the anodal electrode targeting the right DLPFC (https://clinicaltrials.gov/ct2/show/NCT03027687). Smokers were allocated to six sessions of either active tDCS (n = 35) or sham tDCS (n = 36) and received two sessions on three different days in one week. They were asked to keep track of their daily cigarette consumption, craving and affect in an application on their mobile phones for three months starting one week before the first tDCS session. RESULTS: Number of smoked cigarettes a day progressively decreased up to one week after the last tDCS session in both conditions. Active treatment had no additional effect on cigarette consumption, craving and affect. CONCLUSIONS: In this exploratory study, repetitive bilateral tDCS over the DLPFC had no effect on daily smoking behaviour. Future research needs to investigate how motivation to quit smoking and the number of tDCS sessions affect the efficacy of repetitive tDCS.

Sensory processing deficiencies in patients with borderline personality disorder who experience auditory verbal hallucinations.

Auditory verbal hallucinations (AVH) are common in patients with borderline personality disorder (BPD). We examined two candidate mechanisms of AVH in patients with BPD, suggested to underlie sensory processing systems that contribute to psychotic symptoms in patients with schizophrenia; sensory gating (P50 ratio and P50 difference) and change detection (mismatch negativity; MMN). Via electroencephalographic recordings P50 amplitude, P50 ratio, P50 difference and MMN amplitude were compared between 23 borderline patients with and 25 without AVH, and 26 healthy controls. Borderline patients with AVH had a significantly lower P50 difference compared with healthy controls, whereas no difference was found between borderline patients without AVH and healthy controls. The groups did not differ on MMN amplitude. The impaired sensory gating in patients with borderline personality disorder who experience AVH implies that P50 sensory gating deficiencies may underlie psychotic vulnerability in this specific patient group. Patients with borderline personality disorder with or without AVH did not have problems with auditory change detection. This may explain why they are spared from the poor outcome associated with negative symptoms and symptoms of disorganization in patients with chronic schizophrenia.

The Relation Between Trait Anger and Impulse Control in Forensic Psychiatric Patients: An EEG Study.

Inhibitory control is considered to be one of the key factors in explaining individual differences in trait anger and reactive aggression. Yet, only a few studies have assessed electroencephalographic (EEG) activity with respect to response inhibition in high trait anger individuals. The main goal of this study was therefore to investigate whether individual differences in trait anger in forensic psychiatric patients are associated with individual differences in anger-primed inhibitory control using behavioral and electrophysiological measures of response inhibition. Thirty-eight forensic psychiatric patients who had a medium to high risk of recidivism of violent and/or non-violent behaviors performed an affective Go/NoGo task while EEG was recorded. On the behavioral level, we found higher scores on trait anger to be accompanied by lower accuracy on NoGo trials, especially when anger was primed. With respect to the physiological data we found, as expected, a significant inverse relation between trait anger and the error related negativity amplitudes. Contrary to expectation, trait anger was not related to the stimulus-locked event related potentials (i.e., N2/P3). The results of this study support the notion that in a forensic population trait anger is inversely related to impulse control, particularly in hostile contexts. Moreover, our data suggest that higher scores on trait anger are associated with deficits in automatic error-processing which may contribute the continuation of impulsive angry behaviors despite their negative consequences.

Food addiction is associated with impaired performance monitoring.

Currently, there is an ongoing debate about whether it is possible to be addicted to food. There are several indications pointing in this direction, but research is scarce. Up to this date it is not exactly known whether this "food addiction" shares common neurocognitive deficits observed in the more classical types of addictions such as substance use disorders (SUDs). One commonly observed finding in SUD patients is that there is an impaired cognitive control. One of the essential components of cognitive control is performance monitoring. In the present study it is studied whether persons with "food addiction" have impaired error monitoring. For this purpose the performance monitoring of persons meeting the criteria for "food addiction" (n=34) according to the Yale Food Addiction Scale (YFAS) were compared with a control group (n=34) while performing an Eriksen flanker task and EEG measurement. Both electrophysiological (ERN and Pe component) and behavioral measures were compared between the two groups. The present study indicates that the "food addicted" persons have reduced ERN and Pe waves. In addition, the "food addiction" group demonstrates a higher number of errors on the flanker task. In general, the results provide indications that persons with a "food addiction" display impaired performance monitoring. These findings provide an indication that food addiction, similar to other addictions, is characterized by impaired cognitive control.

Cognitive control in young heavy drinkers: An ERP study.

Substance use disorders have been frequently linked to an impaired cognitive control system. Whether this impaired control is also present in young adults who heavily drink alcohol is still subject to debate. The present study investigated possible impairments in cognitive control in heavy drinkers using behavioral and electrophysiological (EEG) measures. We studied behavioral performance on an inhibitory control and an error-processing task, using a GoNogo task and an Eriksen Flanker task respectively, while ERPs (Nogo-N2/P3 and ERN/Pe) were measured in a group of heavy alcohol drinkers (n=48) and a healthy control group of light drinkers (n=49). Results showed very few impairments in the heavy drinking group either at the behavioral or physiological level. One exception was the error-related Pe amplitude. This ERP component was reduced in heavy drinkers as compared to controls. Given that the Pe reflects a motivational component (i.e., the salience attributed to the making of errors) rather than a basic cognitive deficit, it can be concluded that heavy drinking in this population is not associated with major impaired cognitive control, but rather with impairments that are associated with aberrant attribution of salience to the making of errors. The present EEG findings are consistent with recent reviews and large scale epidemiological studies showing that heavy drinking, in contrast to substance use disorders, in young persons is not necessarily associated with major behavioral impairments in cognitive control.

The effect of hippocampal function, volume and connectivity on posterior cingulate cortex functioning during episodic memory fMRI in mild cognitive impairment.

OBJECTIVES: Diminished function of the posterior cingulate cortex (PCC) is a typical finding in early Alzheimer's disease (AD). It is hypothesized that in early stage AD, PCC functioning relates to or reflects hippocampal dysfunction or atrophy. The aim of this study was to examine the relationship between hippocampus function, volume and structural connectivity, and PCC activation during an episodic memory task-related fMRI study in mild cognitive impairment (MCI). METHOD: MCI patients (n = 27) underwent episodic memory task-related fMRI, 3D-T1w MRI, 2D T2-FLAIR MRI and diffusion tensor imaging. Stepwise linear regression analysis was performed to examine the relationship between PCC activation and hippocampal activation, hippocampal volume and diffusion measures within the cingulum along the hippocampus. RESULTS: We found a significant relationship between PCC and hippocampus activation during successful episodic memory encoding and correct recognition in MCI patients. We found no relationship between the PCC and structural hippocampal predictors. CONCLUSIONS: Our results indicate a relationship between PCC and hippocampus activation during episodic memory engagement in MCI. This may suggest that during episodic memory, functional network deterioration is the most important predictor of PCC functioning in MCI. KEY POINTS: • PCC functioning during episodic memory relates to hippocampal functioning in MCI. • PCC functioning during episodic memory does not relate to hippocampal structure in MCI. • Functional network changes are an important predictor of PCC functioning in MCI.

The impact of angry rumination on anger-primed cognitive control.

BACKGROUND AND OBJECTIVES: Recent research suggests that angry rumination augments aggressive behavior by depleting self-control resources. Yet, few studies have been conducted to empirically support this proposal. In the present study, we therefore sought to investigate the effects of angry rumination, relative to distraction, on self-reported anger and a behavioral indicator of self-control. METHODS: Seventy-two participants recalled and imagined an anger-inducing autobiographical memory and were instructed to engage in either angry rumination (n = 37) or distraction (n = 35). Following these emotion regulation instructions, participants performed an affective Go/NoGo task in order to assess behavioral self-control along with several questionnaires to assess anger related constructs. RESULTS: As expected, results revealed that angry rumination augmented anger, whereas anger decreased in the distraction condition. Contrary to predictions, we found no differences between both groups in performance on the affective Go/NoGo task. LIMITATIONS: A potential limitation is we instructed our participants on how to regulate their emotions rather than letting angry rumination occur spontaneously. CONCLUSIONS: The findings indicate that whereas angry rumination results in heightened anger, it does not seem to result in lower self-control as measured with a behavioral task that requires cognitive control. More research is needed to test the boundary conditions regarding the role of self-control in understanding rumination-induced aggression.

Trait anger in relation to neural and behavioral correlates of response inhibition and error-processing.

Effortful control is considered to be an important factor in explaining individual differences in trait anger. In the current study, we sought to investigate the relation between anger-primed effortful control (i.e., inhibitory control and error-processing) and trait anger using an affective Go/NoGo task. Individuals low (LTA; n=45) and high (HTA; n=49) on trait anger were selected for this study. Behavioral performance (accuracy) and Event-Related Potentials (ERPs; i.e., N2, P3, ERN, Pe) were compared between both groups. Contrary to our predictions, we found no group differences regarding inhibitory control. That is, HTA and LTA individuals made comparable numbers of commission errors on NoGo trials and no significant differences were found on the N2 and P3 amplitudes. With respect to error-processing, we found reduced Pe amplitudes following errors in HTA individuals as compared to LTA individuals, whereas the ERN amplitudes were comparable for both groups. These results indicate that high trait anger individuals show deficits in later stages of error-processing, which may explain the continuation of impulsive behaviors in HTA individuals despite their negative consequences.

Brain activity elicited by reward and reward omission in individuals with psychopathic traits: An ERP study.

Psychopathy has been associated with behavioral adaptation deficits, which might be associated with problems in feedback and reward processing. In the present study, we examined the relation between psychopathic traits and reward processing in a passive gambling task. A total of 39 male participants who scored high (HP) and 39 male participants who scored low (LP) on the Triarchic Psychopathy Measure (TriPM), total score were tested. Feedback-related Event-Related Potentials (ERPs; i.e., P2, FRN, and P3) on predicted and unpredicted rewards and reward omissions were compared between both groups. It was found that in HP individuals, the P2 was enhanced for predicted rewards and reward omissions, but not for unpredicted stimuli. Moreover, HP individuals as compared to the LP individuals demonstrated a generally reduced P3 amplitude. The FRN amplitude, however, did not differ between the two groups. In addition, HP individuals showed enhanced reward sensitivity on the self-report level. Taken together, these findings suggest that HP individuals show enhanced sensitivity to early and reduced sensitivity to later markers of processing reinforcement learning signals, which points in the direction of compromised behavioral adaptation.

Validation of the cocaine versions of the Obsessive Compulsive Drug Use Scale and the Desires for Drug Questionnaire.

BACKGROUND: The Obsessive Compulsive Drug Use Scale (OCDUS) and the Desires for Drug Questionnaire (DDQ) are two frequently used drug craving questionnaires. Although both heroin and cocaine versions of the questionnaires exist, only the heroin versions have been psychometrically evaluated. The present study was conducted to evaluate the psychometric qualities of the cocaine versions of the OCDUS (OCDUS-C) and DDQ (DDQ-C). METHODS: Cocaine-dependent inpatients (n = 101) completed both scales as well as a Visual Analogue Craving Scale (VACS), an alternative, one-item index for assessing momentary craving. We examined the reliability (internal consistency), construct validity (factor structure), and concurrent validity (correlations among both questionnaires, the VACS, and indicators of severity of dependence). A subsample also completed the OCDUS-C and DDQ-C for a second time, one week after the initial administration to obtain a preliminary investigation of the test-retest reliability. RESULTS: In general, both questionnaires displayed good internal consistency, test-retest reliability, and concurrent validity. Further, the construct validity of both the DDQ and OCDUS was demonstrated by means of confirmatory factor analyses showing the expected three-factor models. CONCLUSION: Our results indicate that the OCDUS and DDQ for cocaine are both easy to administer and reliable instruments to assist the clinical practitioner or researcher to measure craving in cocaine dependent subjects. Moreover, the factor structure for the cocaine versions were similar to the heroin versions, indicating the OCDUS and the DDQ can be reliably used to measure craving for both substances, enabling a direct comparison between heroin and cocaine craving.

Cardiac and electro-cortical concomitants of social feedback processing in women.

This study provides a joint analysis of the cardiac and electro-cortical-early and late P3 and feedback-related negativity (FRN)-responses to social acceptance and rejection feedback. Twenty-five female participants performed on a social- and age-judgment control task, in which they received feedback with respect to their liking and age judgments, respectively. Consistent with previous reports, results revealed transient cardiac slowing to be selectively prolonged to unexpected social rejection feedback. Late P3 amplitude was more pronounced to unexpected relative to expected feedback. Both early and late P3 amplitudes were shown to be context dependent, in that they were more pronounced to social as compared with non-social feedback. FRN amplitudes were more pronounced to unexpected relative to expected feedback, irrespective of context and feedback valence. This pattern of findings indicates that social acceptance and rejection feedback have widespread effects on bodily state and brain function, which are modulated by prior expectancies.

Preserved emotional memory modulation in first episode psychosis.

Although patients with schizophrenia have severe memory impairments and emotional deficits, studies investigating emotional memory modulation (EMM) in schizophrenia show contradictory results, possibly due to methodological differences and small group size. We investigated whether impaired EMM is already present in First Episode Psychosis (FEP) and whether impairments in EMM are task or stimulus dependent. Forty-five FEP and thirty-seven Healthy Control (HC) male participants matched for age performed visual and verbal short-term (immediate recall) and long-term (after 24h recognition) memory tasks with neutral, negative and positive stimuli. On all tasks overall memory performance for FEP was significantly below that of HC. Although EMM varied by task and type of stimulus, none of the tasks showed a difference in EMM between FEP and HC. There were no differences between FEP and HC in the way emotion modulates different memory domains. This could mean that EMM is spared in the early course of schizophrenia.

Attention modulates the dorsal striatum response to love stimuli.

In previous functional magnetic resonance imaging (fMRI) studies concerning romantic love, several brain regions including the caudate and putamen have consistently been found to be more responsive to beloved-related than control stimuli. In those studies, infatuated individuals were typically instructed to passively view the stimuli or to think of the viewed person. In the current study, we examined how the instruction to attend to, or ignore the beloved modulates the response of these brain areas. Infatuated individuals performed an oddball task in which pictures of their beloved and friend served as targets and distractors. The dorsal striatum showed greater activation for the beloved than friend, but only when they were targets. The dorsal striatum actually tended to show less activation for the beloved than the friend when they were distractors. The longer the love and relationship duration, the smaller the response of the dorsal striatum to beloved-distractor stimuli was. We interpret our findings in terms of reinforcement learning. By virtue of using a cognitive task with a full factorial design, we show that the dorsal striatum is not activated by beloved-related information per se, but only by beloved-related information that is attended.

The heart-break of social rejection versus the brain wave of social acceptance.

The effect of social rejection on cardiac and brain responses was examined in a study in which participants had to decide on the basis of pictures of virtual peers whether these peers would like them or not. Physiological and behavioral responses to expected and unexpected acceptance and rejection were compared. It was found that participants expected that about 50% of the virtual judges gave them a positive judgment. Cardiac deceleration was strongest for unexpected social rejection. In contrast, the brain response was strongest to expected acceptance and was characterized by a positive deflection peaking around 325 ms following stimulus onset and the observed difference was maximal at fronto-central positions. The cardiac and electro-cortical responses were not related. It is hypothesized that these differential response patterns might be related to earlier described differential involvement of the dorsal and ventral portion of the anterior cingulate cortex.

Cytokine removal on extracorporeal life support for treatment of acute endotoxemia: a randomized controlled animal study.

BACKGROUND: We prospectively evaluated the effectiveness of resin adsorption incorporated in an extracorporeal life support (ELS) circuit in an animal model of sepsis for removal of cytokines and prevention of hemodynamic deterioration during the treatment of septic shock. METHODS: Twelve female landrace pigs were randomly assigned to two groups, a study group(n=6), treated with high-flow resin adsorption (300 mL/min) and ELS, and a control group (n=6), treated only with ELS. Septic shock was induced by intravenous 0.02 µg/kg/min infusion was of Escherichia coli lipopolysaccharide (LPS). Measurements were carried out in the study group at baseline, at the end of LPS injection(t0) at 30(t1), 60(t2), 90(t3) and 120 min (t4) and 60 min after stopping resin-adsorption (t5). In the control group measurements were performed at baseline (t0), t1 and only t2, as no control animal survived beyond this latter experimental timepoint. RESULTS: The final population consisted of 9 animals, five in the study group and 4 in the control group. Plasma values of both tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) were reduced during resin-adsorption (t1-t4) while these mediators increased in controls undergoing ELS only. With a clearance of TNF-α of 15,233 pg/min and IL-6 of 10,233 pg/min, 79.2% of TNF-α and 95.3% of IL-6 produced were adsorbed. Systemic vascular resistance decreased significantly in both groups at t0. While it further was reduced during the control experiments at t1 and t2, it returned to normal in the study animals. Cardiac output increased at t0, t1 and t2 in the control experiments. In contrast, in study animals after a peak at t0, it returned to the baseline value and did not vary thereafter. CONCLUSIONS: Combined resin-adsorption and ELS improved hemodynamics resulting from effective removal of inflammatory mediators in a pig model of septic shock.