Biomedical subjects

Ingmar H A Franken

Publications and source records attributed to Ingmar H A Franken.

At least 19 recordsLinked to original sources

PubMed2007

Cue exposure therapy for the treatment of opiate addiction: results of a randomized controlled clinical trial.

BACKGROUND: Persistent cue reactivity to drug-related stimuli is a well-known phenomenon among abstinent drug users and has been found to be a predictor of relapse. Cue exposure therapy (CET) aims to reduce this cue reactivity by exposing abstinent drug users to conditioned drug-related stimuli while preventing their habitual response, i.e. drug use. METHODS: 127 abstinent heroin-dependent Dutch inpatients were randomized to CET (n = 65; 55 completers) and placebo psychotherapy treatment (PPT) (n = 62; 59 completers). It was examined whether CET would lead to a decrease in drug-related cue reactivity (using mixed-design ANOVA) and subsequently to lower dropout and relapse rates (using logistic regression) compared to PPT. RESULTS: Both groups responded with a similar decrease in self-reported cue reactivity (craving, mood). The CET group did show a significant decrease in physiological reactivity (skin conductance) compared to PPT. However, dropout and relapse rates were, contrary to our expectations, significantly higher in the CET group. CONCLUSIONS: This is the first randomized controlled trial showing that CET, compared to a non-specific psychotherapy, might increase dropout and relapse rates among abstinent heroin-dependent clients in a drug-free setting. Caution is warranted when applying CET in this specific context.

Adult↗

PubMed2006

Error-processing deficits in patients with cocaine dependence.

Cocaine abuse and addiction can be characterized by a persisting use of cocaine in the face of adverse consequences. In the present study we focus on one specific element of adverse consequences: the making of errors. The aim of this study was to determine whether cocaine-dependent persons have error-processing deficits as measured using error-related negativity (ERN) and error positivity (Pe). Event-related potentials (ERPs) during an Eriksen flanker task were recorded from cocaine-dependent patients and a control group. Cocaine-addicted patients showed reduced ERN and Pe components as compared to a control group. On the behavioral level, patients showed reduced post-error accuracy improvement. The present findings reveal that cocaine addiction is associated with reduced error processing and impaired behavioral correction of errors after an error is made. These deficits may be associated with a compromised dopamine system. It is argued that these cognitive deficits may contribute to the maintenance of the cocaine addiction.

Adult↗

PubMed2006

The modified Trait and State Food-Cravings Questionnaires: development and validation of a general index of food craving.

In the present study, the multidimensional Trait and State Food Cravings Questionnaires (FCQ-T and FCQ-S), as developed by Cepeda-Benito, Gleaves, Williams, and Erath, [2000. The development and validation of the State and Trait Food Cravings Questionnaires. Behavior Therapy, 31, 151-173], were modified in order to construct an index of general food craving instead of specific food craving. The factor structure, validity and reliability of the modified questionnaires, renamed as the Trait and State General Food Cravings Questionnaires (G-FCQ-T and G-FCQ-S), were investigated in three separate studies. Firstly, exploratory factor analyses were conducted, which yielded a G-FCQ-T with a four-factor structure, that was considerably shorter as compared to the original (nine-factor) FCQ-T, and a G-FCQ-S of which the factor structure was highly comparable to the original FCQ-S. Secondly, in an attempt to replicate the factor structures of the G-FCQ-T and the G-FCQ-S as found in Study 1, confirmative factor analyses were performed. Results indicated adequate fits for both questionnaires. In addition, the test-retest reliability of both versions was satisfactory and an analysis of the construct validity generally revealed the expected results. In Study 3, the validity of the state version of the G-FCQ was further investigated by relating scores on this questionnaire to indices of food deprivation and satiation. Results indicated that the G-FCQ-S indeed measures food craving as a variable state, which is influenced by situational and temporal variables. Altogether, it can be concluded that the G-FCQ-T and G-FCQ-S are both reliable and valid measures of general trait-like and state-dependent food craving.

Adolescent↗

PubMed2006

The assessment of anhedonia in clinical and non-clinical populations: further validation of the Snaith-Hamilton Pleasure Scale (SHAPS).

BACKGROUND: Anhedonia, the inability to experience pleasure, is a major endophenotype of depression. In addition to this, it is an important clinical feature of schizophrenia and substance abuse disorders. Valid instruments to measure anhedonia are sparse. METHODS: In the present study, a short, 14-item instrument, the Snaith-Hamilton Pleasure Scale (SHAPS) to measure anhedonia in normal and clinical samples was further validated. Various aspects of the reliability and validity of the SHAPS that have not been addressed before, were examined in three separate studies. First, we assessed the internal consistency, convergent and discriminative validity of the SHAPS in a non-clinical sample. Second, the test-retest reliability of the SHAPS was investigated in another sample. In the third study, the internal consistency, convergent and discriminative validity of the SHAPS was tested by administering the scale in three clinical samples of psychiatric inpatients. RESULTS: The SHAPS was found to be highly reliable in terms of internal consistency and test-retest stability. Further, the SHAPS correlated in a theoretically meaningful way with other measures of affect and personality. Patients with a depression, psychosis or substance dependence scored significantly higher on the SHAPS than non-patient controls. Patients with a depression displayed the highest SHAPS-score. LIMITATIONS: The absence of structured assessment data to validate the clinical diagnoses. CONCLUSIONS: The current study shows that the SHAPS is a reliable and valid questionnaire to assess hedonic tone in patient and non-patient populations. Because it is a brief scale it seems to be a very useful instrument for measuring anhedonia in clinical and research settings.

Adolescent↗

PubMed2006

Effect of hedonic tone on event-related potential measures of cognitive processing.

Anhedonia, the inability to experience pleasure, is a core feature of several psychiatric disorders such as schizophrenia, depression, and substance dependence. Furthermore, it has been suggested that anhedonia is an important predictor of schizophrenia. Anhedonia has been associated with information-processing deficits, especially attentional deficits, which may predispose for schizophrenia. In the present study, event-related potentials (ERPs) were used to examine the influence of hedonic tone on information-processing characteristics in a sample of healthy individuals. Thirty-five healthy subjects were divided into two groups based on their scores on the Snaith-Hamilton Pleasure Scale (SHAPS). Cognitive functions were measured during an active visual oddball paradigm. It was found that both early, middle and late ERP components of subjects with low levels of hedonic tone were attenuated compared with ERPs of subjects with high levels of hedonic tone. These findings suggest that decreased hedonic tone is associated with reductions in both automatic and effortful cognitive processing of relevant stimuli. Consequences of these findings for the vulnerability to psychopathology are discussed.

Adolescent↗

PubMed2006

Attentional bias predicts heroin relapse following treatment.

AIMS: Previous studies have shown that abstinent heroin addicts exhibit an attentional bias to heroin-related stimuli. It has been suggested that attentional bias may represent a vulnerability to relapse into drug use. In the present study, the predictive value of pre-treatment attentional bias on relapse was examined in a population of abstinent heroin addicts. Further, the effect of cue exposure therapy (CET) on attentional bias was studied. DESIGN: Participants were assigned randomly to receive nine sessions of CET or placebo psychotherapy. SETTING: An in-patient drug abuse treatment setting. PARTICIPANTS: Abstinent heroin-dependent patients. MEASUREMENTS: Participants completed the emotional Stroop task both before and after completing treatment. FINDINGS: Pre-treatment attentional bias predicted relapse at 3-month follow-up, even when controlling for self-reported cravings at the test session. Further, attentional bias was reduced in both groups after therapy, independent of treatment condition. CONCLUSIONS: Attentional bias may tap an important component of drug dependence as it is a predictor of opiate relapse. However, CET does not specifically reduce attentional bias.

Attention↗

PubMed2005

Are nonpharmacological induced rewards related to anhedonia? A study among skydivers.

It is well-known that persons with a drug addiction experience feelings of anhedonia during "normal" daily activities. It has been proposed that these symptoms of anhedonia are the result of direct pharmacological influences of drugs on the dopamine system. To test the assumption that nonpharmacological processes are also involved in anhedonia, we studied anhedonic symptoms in skydivers who regularly expose themselves to thrillful extreme sport activity and then experience intense hedonic feelings. A group of skydivers completed anhedonia scales and their scores were compared to a control group (a group of rowers). The main finding of the present study was that subjects who engage in the high-risk activity of skydiving, experienced more anhedonic symptoms than subjects who do not engage in such an extreme sport, but rather prefer a low-risk activity like rowing. This finding supports the notion that skydiving has similarities with addictive behaviors and that frequent exposure to "natural high" experiences is related to anhedonia. This suggests that the negative emotional state as observed in drug users may not be exclusively the results of exogenous psychopharmacological effects, but might also result from psychological mechanisms that are partly responsible for these anhedonic feelings.

Adult↗

PubMed2005

The role of dopamine in human addiction: from reward to motivated attention.

There is general consensus among preclinical researchers that dopamine plays an important role in the development and persistence of addiction. However, the precise role of dopamine in addictive behaviors is far from clear and only a few clinical studies on the role of dopamine in human addiction have been conducted so far. The present paper reviews studies addressing the role of dopamine in humans. There is substantial and consistent evidence that dopamine is involved in the experience of drug reward in humans. Dopamine may also be involved in motivational processes such as drug craving. However, given the inconsistent findings of studies using dopamine receptor (ant)agonists, the role of dopamine in the experience of craving is far from resolved. Recent theories claiming that dopamine signals salience and makes the brain paying attention to biological relevant stimuli may provide an interesting framework for explaining addictive behaviors. There is accumulating evidence that patients with drug and alcohol addiction have an aberrant focus on drug-related stimuli. Although there is some preliminary support for the role of dopamine in these attention processes, more studies have to be carried out in order to test the validity of these theories in human subjects.

Attention↗

PubMed2005

Gray's model of personality and addiction.

It has been suggested that high levels of behavioral approach system (BAS) sensitivity predispose psychopathological conditions that are characterized by a pathological engagement in approach behaviors, such as alcohol and drug abuse. The present study examined differences in scores on the BIS/BAS scales between clinically referred drug addicts and alcoholics and healthy control subjects. Results showed that drug addicts had higher BAS scores than controls and this was particularly true for BAS drive and BAS fun seeking. No differences were observed between the alcoholics and the other two groups. This is the first time that a relation between heightened BAS and drug addicts is observed in a clinical sample. These findings provide partial support for Gray's personality theory, which predicts a relation between BAS and substance abuse.

Adult↗

PubMed2005

Impulsivity affects mismatch negativity (MMN) measures of preattentive auditory processing.

The current study addresses the relation between impulsive personality and mismatch negativity (MMN) as measure of auditory processing. In a sample of 33 normals, MMN was measured and related to self-reported measures of impulsive behavior. Participants were tested using a passive auditory oddball paradigm while EEG recordings were obtained. It was found that the negative MMN amplitude at the left lateral cluster was negatively correlated with self-reported impulsivity, with high impulsive individuals showing larger MMN amplitudes than low impulsive individuals. This indicates that impulsivity is related to preattentive auditory processing, a process that is not dependent on response execution. In addition to the well-known involvement of top-down control in impulsivity, these findings implicate that the cognitive bottom-up processing of incoming stimuli is associated with individual differences in impulsivity. Since the source of the MMN is thought to be located in the auditory cortex, this suggests involvement of "lower order" temporal lobe processes in impulsive behaviors.

Adolescent↗

PubMed2005

Individual differences in reward sensitivity are related to food craving and relative body weight in healthy women.

According to the theory of J.A. Gray, a strongly reactive approach system is highly sensitive to reward or to cues that signal reward. This implies that intake driven by the rewarding properties of food should be affected by individual differences in reactivity of the approach system. The present study examined whether reward sensitivity is associated with food craving and relative body weight in a sample of female college students. Participants completed the Sensitivity to Punishment and Sensitivity to Reward Questionnaire and the trait version of the Food Craving Questionnaire and also reported their weight and height in order to compute Body Mass Index (BMI). Sensitivity to reward was significantly related to food craving and BMI. Furthermore, the correlation between reward sensitivity and BMI was not attenuated when the influence of food craving was partialled out, indicating that the relation between sensitivity to reward and BMI was not mediated by food craving. This is the first study demonstrating a relation between the personality trait of sensitivity to reward and BMI. These findings are discussed in the context of the involvement of dopaminergic reward circuitry in overeating.

Adolescent↗

PubMed2005

Generalizability of carry-over effects in the emotional Stroop task.

The emotional Stroop task has been the most widely used task to examine attentional bias to emotionally salient stimuli. In one format of this task, words are presented to participants in a mixed randomized or quasi-randomized sequence. Using a mixed smoking Stroop task, we have previously demonstrated that smokers are slower to respond to words which follow smoking-related words than words which follow neutral words. Here we show that this carry-over effect is present in heroin addicts-but not control subjects-in a heroin Stroop task, and in normal subjects in a stress Stroop task. Thus, the effect generalizes to other populations. In addition, an examination of the studies that have collected data from both mixed and blocked formats provides converging evidence for the presence of carry-over effects. We discuss the implications of the carry-over effect for research using the emotional Stroop task.

Adult↗

PubMed2005

The relation between social desirability and different measures of heroin craving.

A low association between self-reported craving and physiological measures of craving is often found. Social desirability might influence this relation between subjective and physiological reactivity. Subjects were seventy-six in-patient abstinent heroin abusers. Social desirability, general craving scores and difference scores of physiological and subjective heroin craving, measured after exposure to a neutral and heroin cue were assessed. Cue reactivity, both subjective and physiological was found to be enhanced after exposure to a heroin-related cue. In line with earlier studies, a modest relation was found between subjective and physiological cue reactivity. Contrary to earlier research, however, high social desirability scores were associated with lower craving scores, but not with physiological scores. It can be concluded that, among other subject-related variables, social desirability influences self-reported craving but does not influence physiological reactivity in a clinical population. No significant moderation effect of social desirability on the relation between subjective and physiological reactivity was found.

Adult↗

PubMed2004

Event-related potentials indicate motivational relevance of cocaine cues in abstinent cocaine addicts.

RATIONALE: Motivational drive and its underlying affect-related states are the core mechanisms that precede the seeking and taking of drugs in substance dependence. OBJECTIVE: The present study aimed to investigate the motivational relevance of cocaine cues and whether or not an appetitive emotional system is involved employing event-related potential (ERP) measurements. METHODS: Cocaine-addicted subjects and healthy controls were exposed to neutral and cocaine-related pictures whilst ERPs were recorded simultaneously over frontal, parietal and midline sites. RESULTS: Patients exhibited ERP amplitude discrepancies between neutral and cocaine-related pictures for N300, late slow positive wave (LSPW) and sustained slow positive wave (SSPW), whilst this effect was absent in control subjects. Differences in neutral and cocaine cue-evoked ERP waves were also found at left frontal sites for LSPW and SSPW in the patient group only. No group-specific cue-evoked ERP amplitudes were observed at parietal and midline sites. CONCLUSION: The findings confirm the assumption that cocaine cues induce motivational relevance in cocaine-dependent individuals. It is possible that exposure to cocaine cues triggers an appetitive emotional system since left frontal sites are assumed to be involved in processing positive emotional-laden stimuli. The present study provides evidence that the sensitivity of ERP correlates for cocaine cues may be an indicator of motivational and emotional processes in drug-dependent individuals.

Adult↗

PubMed2004

A role for dopamine in the processing of drug cues in heroin dependent patients.

Drug and alcohol dependence are associated with enhanced attention for drug-related stimuli. This cognitive processing bias has been suggested to be related to craving and to represent one of the core mechanisms of addition. The present study tests the hypothesis that enhanced attention for heroin cues is mediated by the dopaminergic system using haloperidol as dopamine antagonist. In a double blind, randomized crossover design, 17 detoxified heroin dependent patients received a single oral dose of haloperidol 2 mg and placebo. Patients performed an Emotional Stroop Task to assess the cognitive processing of drug cues under both conditions. In addition, self-reported craving was assessed. In the haloperidol condition, patients performed better on the Emotional Stroop Task than in the placebo condition. However, no effect of haloperidol on subjective craving was found. These findings provide preliminary indications that attentional bias in heroin dependent humans is mediated by dopaminergic mechanisms.

Adult↗

PubMed2004

Electroencephalographic power and coherence analyses suggest altered brain function in abstinent male heroin-dependent patients.

Previous studies have shown that drug abuse is associated with altered brain function. However, studies of heroin abuse-related brain dysfunctions are scarce. Electroencephalographic (EEG) power and coherence analyses are two important tools for examining the effects of drugs on brain function. In the present study, we compared EEG power and coherence measures of 18 abstinent heroin-dependent subjects with those of 12 healthy control subjects. Furthermore, within the heroin group, associations between heroin use in the past, heroin craving and these EEG measures were studied. The results show that heroin-dependent subjects have increased relative beta-2 power and increased left intrahemispheric gamma coherence compared with control subjects. Furthermore, coherence measures showed correlations with clinical variables. These EEG abnormalities may reflect underlying changes in brain function due to long-term drug abuse and premorbid characteristics.

Adult↗

PubMed2004

Two new neurophysiological indices of cocaine craving: evoked brain potentials and cue modulated startle reflex.

Craving for cocaine is one of the hallmarks of cocaine dependence. One of the problems with craving is its measurement. Traditional psychophysiological indices such as skin conductance and heart rate have yielded contradictory results. These measures of craving were found to correlate only moderately with self-reported craving. In the present study, event-related brain potentials (ERPs) and the cue modulated startle response (CMSR) are evaluated as indices for cocaine craving. Twenty-one abstinent cocaine-dependent subjects were divided into high and low cravers group based on the median split of self-reported craving scores. ERPs and CMSR were measured when subjects watched neutral, pleasant, unpleasant and cocaine-related pictures. Overall, it was found that cocaine-dependent subjects showed augmented slow-positive waves (SPWs) of the ERP on the cocaine pictures compared to neutral pictures. Only high cravers showed larger SPWs on the cocaine cues, suggesting an association between cue-elicited SPWs and self-reported cocaine craving. By contrast to the ERP measures, CMSR did not differentiate between cocaine pictures and neutral pictures. In addition, no differences between the low- and high cravers on the CMSR measure were found. The present results show that the evoked-potentials paradigm provides promising results to index cue-elicited craving. The use of startle modulation deserves further investigation.

Adult↗

PubMed2003

Neurophysiological evidence for abnormal cognitive processing of drug cues in heroin dependence.

RATIONALE: Recent studies provide evidence for specific aspects of cue processing in addictive disorders. OBJECTIVE: The present study employs event related potentials (ERPs) to investigate heroin related visual information processing. METHODS: Neutral and heroin related pictures were presented to 19 male abstinent heroin dependent patients and 14 male healthy controls. RESULTS: Patients exhibited larger slow positive wave (SPW) components of the ERP on heroin related pictures than on neutral pictures. Within healthy control subjects there was no difference on the SPW between neutral and heroin pictures. Within heroin dependent patients, mean SPW response to heroin pictures was correlated with post-experiment craving. CONCLUSION: This study provides neurophysiological evidence that information processing of drug-related information is abnormal in heroin dependent patients. The results provide further evidence for the cognitive and neurobiological accounts of substance dependence such as the incentive-sensitization theory.

Behavior, Addictive↗