PubMed Health⌕ Search

Biomedical subjects

P Verbanck

Publications and source records attributed to P Verbanck.

At least 19 recordsLinked to original sources
PubMed2007

Is the P300 deficit in alcoholism associated with early visual impairments (P100, N170)? An oddball paradigm.

OBJECTIVE: Studies exploring chronic alcoholism with event-related potentials (ERPs) have shown delayed latency and reduced amplitude of the P300, a long-lasting positive potential reflecting decisional processing. This P300 deficit in alcoholism is generally interpreted as a disturbance in central nervous system inhibition or in memory/attention. The present study aimed at identifying if this electrophysiological deficit is already present on earlier components, and advances a new hypothesis concerning the interpretation of the P300 alteration. METHODS: Patients suffering from alcoholism and matched healthy controls had to detect, in an oddball paradigm, emotional faces among a succession of neutral faces. Behavioral performance and ERP data (recorded from 32 electrodes) were analyzed. RESULTS: In line with previous studies, data showed that alcoholism led to a P300 deficit. Moreover, we observed for the first time that this deficit begins at earlier visual (P100) and face-processing (N170) stages, and we found high positive correlations between P100, N170 and P300 for amplitude and latency values, suggesting cumulative deficits on the cognitive continuum. CONCLUSIONS: We suggest that the P300 deficit observed in chronic alcoholism could be linked to earlier visuo-spatial deficits rather than being an impairment of the specific processes linked to the P300. SIGNIFICANCE: These results call for reconsidering the interpretation of P300 impairments at a fundamental and clinical level, and shows that earlier ERP components must be taken into account in future studies.

Alcoholism↗
PubMed2006

Early visual components (P100, N170) are disrupted in chronic schizophrenic patients: an event-related potentials study.

INTRODUCTION: On the basis of the Positive and Negative Syndrome Scale (PANSS), fourteen schizophrenic patients and 7 normal controls were confronted with pictures from the Ekman & Friesen series in an event-related potentials study. PROCEDURE: Participants were confronted with a visual face-detection task, in which they had to detect, as quickly as possible, deviant faces amongst a train of standard stimuli (neutral faces). Deviant faces changed either on identity (different identity, neutral expression), or on emotion (same identity, happy, fearful or sad expression). RESULTS: Schizophrenics exhibited a decrease in amplitude of the face N170, recorded around 170 ms at occipito-temporal sites; this was observed as well for emotional as for identity faces, which suggests a global involvement of face processing. Moreover, this decrease of the face-N170 was positively correlated to positive, but not negative, symptoms of schizophrenia. Finally, the amplitude of P100 was also decreased, which suggests that the N170 decrement would result from a more global deficit in visual processing deficit. DISCUSSION: It is suggested that, in schizophrenics, an involvement of early visual processing might underlie the decreased amplitudes and the higher onset latencies of later P300 and N400 components.

Adult↗
PubMed2006

[Experience of obesity's treatment by an interdisciplinary team].

Owing to the multifactorial origin of obesity, we have created an interdisciplinary team devoted to a limited-in-time treatment, following three axles : nutritional education, body self-perception and emotions expression. The philosophy of this approach and some results are presented.

Humans↗
PubMed2005

Effect of community nurse follow-up when treating alcohol dependence with acamprosate.

AIMS: To measure the effect of community nurse follow-up on abstinence and retention rates in the outpatient treatment of alcohol-dependent patients treated with acamprosate. METHODS: Recently detoxified alcohol-dependent patients were prescribed acamprosate for 26 weeks and randomized to either physician-only follow-up, or physician plus regular visits from a community nurse. Drinking behaviour in the next 26 weeks was assessed at monthly visits to non-blind clinicians. RESULTS: The cumulative abstinence duration proportion (CADP) was significantly longer in (P=0.03) the subjects who had received community nurse support (0.57) than in those who had not (0.39). This might, in part, be an artefact of the higher retention rate among those followed up by the nurse, in that, the method of calculating CADP allocates 100% days of drinking for the month before a failed attendance. Differences favouring nurse in the follow-up were seen for time to first drink, and clinical global impression. CONCLUSIONS: For recently detoxified alcohol-dependent patients treated with acamprosate, follow-up by a community nurse improves patient retention and probably also improves the 6-month drinking outcome.

Acamprosate↗
PubMed2004

Personality profile and drug of choice; a multivariate analysis using Cloninger's TCI on heroin addicts, alcoholics, and a random population group.

As personality may predispose, precipitate or perpetuate substance abuse and/or dependence, and as it is considered to remain stable across the years in a given subject, potential links with the drug of choice may help screen future patients before drug consumption. The present study compared three groups: 42 patients with heroin dependence (mean age: 31.2; standard deviation (SD): 5.5; 10 females), 37 patients with alcohol dependence (mean age 44.2; SD: 9.1; 9 females) and 83 subjects from a random population sample (mean age: 38.8; SD: 6.9; 20 females). Personality was measured by Cloninger's Temperament and Character Inventory (TCI). Pillai's MANCOVA with age as a covariate and gender as a cofactor was highly significant. Univariate ANOVA analyses using TCI dimensions as dependent variable showed most variables to vary in parallel for the two patient groups in comparison with controls. Post-hoc tests showed heroin patients to score higher in Novelty-Seeking and Self-Directedness than alcohol patients. Sub-dimensions Exploratory Excitability, Fear of the Uncertain, Responsibility, Congruent Second Nature and Transpersonal Identification were also significantly different in the two patient samples. Logistic regression showed Exploratory Excitability to segregate up to 76% of heroin patients from alcohol patients. In conclusion, personality profiles were linked to some preferential choice of drug and personality screening might be tested in preventive strategies.

Adult↗
PubMed2003

Alcohol and withdrawal: from animal research to clinical issues.

The withdrawal syndrome in alcohol-dependent patients appears to be a major stressful event whose intensity increases with repetition of detoxifications according to a kindling process. Disturbances in the balance between excitatory and inhibitory neural processes are reflected in a perturbed physical state while disturbances in the balance between positive and negative reinforcements are reflected in a perturbed mood state. Our purpose is to link the different behavioral outcomes occurring during withdrawal with specific biological brain mechanisms from the animal to the human being. Better understanding of the various biological mechanisms underlying withdrawal from alcohol will be the key to design and to apply appropriate pharmaceutical management, together with appropriate therapy aimed at inducing protracted abstinence.

Alcohol-Induced Disorders, Nervous System↗
PubMed2002

[Clinical and therapeutic aspects in the treatment of alcohol addiction].

The alcohol-withdrawal syndrome is a well-known clinical situation, so does its treatment. However, new researches have shown that the risk of severe withdrawal manifestations increases proportionally with the number of previous detoxifications, according to a sensitisation stress model. As a consequence, special attention should be paid to patients with a clinical history of multiple alcohol detoxifications, even if they never previously had delirium tremens and/or comitiality. Even in the absence of characteristic neurologic lesions, long-lasting heavy drinking is associated with brain dysfunction, concerning mostly the frontal cortex. This is clinically associated to neuropsychological deficits, specifically disorders of working memory and the so-called "executive functions". These deficits have a dramatic importance, because they impair drastically the outcome of alcoholic patients after detoxification. In Belgium like in other countries, an increasing prevalence of hepatitis C is present in alcoholic patients. This is due probably to the increase of a former illegal drugs consumption in those patients. This association between alcoholism and hepatitis C is of major importance, because alcohol consumption increases the viral load and the risk of cirrhosis and hepatocarcinoma. Furthermore, alcohol reduces the response to interferon therapy.

Alcohol Withdrawal Seizures↗
PubMed2001

Interference with withdrawal signs of naloxone-induced opiate withdrawal under anesthesia is anesthetic-specific in opiate-dependent rats.

We hypothesized that interference of opiate antagonist-precipitated withdrawal signs under anesthesia is anesthetic-specific. Three groups of morphine-dependent rats were compared in different experimental conditions using a protocol of rapid withdrawal induction by an antagonist under anesthesia. We observed that ketamine and midazolam have different effects on the expression of withdrawal. This brings specific insights into the pharmacological basis of therapy with induction of opiate antagonist.

Anesthesia, General↗
PubMed2001

Impaired emotional facial expression recognition in alcoholism compared with obsessive-compulsive disorder and normal controls.

Emotional facial expression (EFE) decoding skills have been shown to be impaired in recovering alcoholics (RA). The aim of the present study is to replicate these results and to explore whether these abnormalities are specific to alcoholism using two control groups: non-patient controls (NC) and patients with obsessive-compulsive disorder (OC). Twenty-two alcoholic patients at the end of their detoxification process (RA) were compared to 22 OC and 22 NC matched for age, sex and education level. They were presented with 12 photographs of facial expressions portraying different emotions: happiness; anger; and fear. Each emotion was displayed with mild (30%) and moderate (70%) intensity levels. Each EFE was judged on 8 scales labeled happiness, sadness, fear, anger, disgust, surprise, shame and contempt. For each scale, subjects rated the estimated intensity level. RA were less accurate in EFE decoding than OC and NC, particularly for anger and happiness expressions. RA overestimated the emotional intensity for mild intensity level expressions compared with both OC and NC while no significant differences emerged for moderate intensity level expressions. Deficits in EFE decoding skills seem to be specific to RA when compared with OC. Comparison with other psychopathological groups is still needed. Possible consequences of EFE decoding deficits in RA include distorted interpersonal relationships.

Adult↗
PubMed2001

Supervisory attentional system in nonamnesic alcoholic men.

BACKGROUND: Many studies have shown that recently detoxified alcoholic persons perform poorly on tasks thought to be sensitive to frontal lobe damage, supporting the hypothesis that the frontal lobes are highly vulnerable to chronic alcohol consumption. However, it appeared that most of the executive tasks used in these studies also involved nonexecutive components, and these tasks had been shown to be impaired as a result of nonfrontal lobe lesions. In this study, we examined further the "frontal lobe vulnerability" hypothesis using executive tasks, proved to be associated with frontal lobe functioning, that allowed us to distinguish the relative importance of executive and nonexecutive processes. METHOD: Thirty recently detoxified asymptomatic male alcoholic inpatients and 30 control subjects were tested for planning, inhibition, rule detection, and coordination of dual task, as well as the speed of processing and nonexecutive functions (such as short-term memory storage). RESULTS: Alcoholics performed worse than controls in almost all tasks assessing executive functions. However, they were not slower than the controls and showed normal results for nonexecutive functions. CONCLUSIONS: Chronic alcohol consumption seems to be associated with severe executive function deficits, which are still present after a protracted period of alcohol abstinence. These data support the idea that the cognitive deficits in recently detoxified sober alcoholic subjects are due, at least partly, to frontal lobe dysfunctioning.

Adult↗
PubMed2001

An atypical neuropsychological profile of a Korsakoff syndrome patient throughout the follow-up.

The basis of amnesia in alcoholic Wernicke-Korsakoff syndrome (WKS) has been generally associated with diencephalic lesions and more specifically with lesions of the anterior thalamic nuclei. These brain structures are considered to be involved in encoding/consolidation processes of episodic memory. However, frontal lobe damage responsible for executive function deficits has also been documented. The present report details the nature and extent of amnesia in an alcoholic patients with WKS and which appears to be mainly due to frontal lobe (executive) deficits.

Alcohol Amnestic Disorder↗
PubMed2001

Deficits in recognition of emotional facial expression are still present in alcoholics after mid- to long-term abstinence.

OBJECTIVE: Emotional facial expression (EFE) decoding skills play a key role in interpersonal relationships. Decoding errors have been described in several pathological conditions, including alcoholism. The aim of this study was to investigate whether EFE decoding skill deficits persist after abstention from alcohol of at least 2 months. METHOD: Alcoholic patients abstinent for at least 2 months (n = 25) were compared with 25 recently detoxified patients and with 25 normal controls matched for age, gender and educational level. Subjects were presented with 40 photographs of facial expressions portraying happiness, anger, sadness, disgust and fear. Each emotion was displayed with neutral, mild, moderate and strong emotional intensity. Each facial expression was judged successively on eight scales labeled happiness, sadness, fear, anger, disgust, surprise, shame and contempt. For each scale, subjects rated the estimated intensity level. A complementary scale assessed the self-estimated difficulty in performing the task. RESULTS: Recently detoxified alcoholics were significantly less accurate than controls, making more EFE labeling errors and overestimating the intensity of the portrayed emotions. Deficits in decoding accuracy for anger and disgust were present in mid- to long-term abstinent patients; intensity overestimation was present in the former and absent in the latter. CONCLUSIONS: Deficits in decoding accuracy for anger and disgust, and to a lesser degree sadness, persist with an abstinence of 2 months and beyond. Right frontotemporal regions and cingulate could be implicated. These deficits may contribute to the social skills deficits frequently encountered in alcoholic patients.

Adult↗
PubMed2000

Previous anesthesia can temporarily overshadow the expression of a withdrawal syndrome in opiate dependent rats.

We hypothesized that induction of opiate antagonist-precipitated withdrawal under anesthesia can decrease the expression of later withdrawal signs. Three groups of morphine-dependent rats were compared in different experimental conditions of withdrawal precipitation using naloxone. We showed that anesthesia can temporarily overshadow the expression of withdrawal signs, but that some signs can be delayed and increased in intensity. This can be explained by a parallel and temporary effect of anesthesia on arousal and pain threshold. This carries important implications on the use of anesthesia in detoxification procedures.

Analysis of Variance↗
PubMed1999

Alcoholics' deficits in the decoding of emotional facial expression.

The present study investigated emotional facial expression decoding in alcoholics. Twenty-five alcoholic patients at the end of the detoxification process were compared with 25 volunteers matched for age, sex, and education. They were presented with facial expressions of neutral, mild, moderate, or strong emotional intensity. Results indicate that alcoholics overestimate the intensity of emotional expressions and make more errors in their decoding with a special bias for anger and contempt. Moreover, this decoding deficit is not perceived by the alcoholic patients. A general model is proposed that links visuospatial deficits, abnormal processing of social information, interpersonal stress, and alcohol abuse.

Adult↗
PubMed1998

Divergent responses to fluoxetine from two compulsive, food-related conditions: bulimia nervosa and compulsive water drinking.

BACKGROUND: The association of compulsive water drinking with bulimia nervosa is rarely encountered. Nevertheless similar behavior patterns could involve a common pathophysiological mechanism. METHODS: A case report with the association of those two disorders is described. Treatment with fluoxetine was introduced to alleviate the compulsive aspects of those disorders. RESULTS: Fluoxetine had a positive effect on bulimia nervosa but none on compulsive water drinking. CONCLUSIONS: The different response to pharmacologic treatment could mean that bulimia nervosa and compulsive water drinking are based on different physiological mechanisms.

Adult↗
PubMed1998

Does sleep EEG data distinguish between UP, BPI or BPII major depressions? An age and gender controlled study.

Clinical characteristics and sleep EEG data of 14 unipolar (UPR), 14 bipolar I (BPI) and 14 bipolar II (BPII) patients, matched for age and gender, were investigated during a major depressive episode. We observed a remarkable similarity in the clinical characteristics of the three samples and, concerning sleep EEG data, a trend to a higher percentage of awakening among BPI patients. Pairwise comparisons of the three subgroups showed that only the Newcastle rating scale score reached significant difference between BPI and UPR groups. We observed trends regarding the difference of awakening both between BPI and BPII groups and between BPI and UPR groups, difference of percentage of REM sleep between BPI and BPII groups and difference of Sleep Period Time between BPII and UPR groups. We also observed that the distribution of REM latencies in the BPI subgroup was different from the two others.

Adult↗