Visuospatial information processing in intoxicated, recently detoxified, and long-term abstinent alcoholics

Repeated diazepam administration reversed working memory impairments and glucocorticoid alterations in the prefrontal cortex after short but not long alcohol-withdrawal periods

The study was designed to assess whether repeated administration of diazepam (Valium®, Roche)-a benzodiazepine exerting an agonist action on GABA_A receptors-may alleviate both the short (1 week, 1W) and long-term (6 weeks, 6W) deleterious effects of alcohol withdrawal occurring after chronic alcohol consumption (6 months; 12% v/v) in C57/BL6 male mice. More pointedly, we first evidenced that 1W and 6W alcohol-withdrawn mice exhibited working memory deficits in a sequential alternation task, associated with sustained exaggerated corticosterone rise and decreased pCREB levels in the prefrontal cortex (PFC). In a subsequent experiment, diazepam was administered i.p. for 9 consecutive days (1 injection/day) during the alcohol withdrawal period at decreasing doses ranging from 1.0 mg/kg to 0.25 mg/kg. Diazepam was not detected in the blood of withdrawn mice at the time of memory testing, occurring 24 hours after the last diazepam injection. Repeated diazepam administration significantly improved alternation rates and normalized levels of glucocorticoids and pCREB activity in the PFC in 1W but not in 6W withdrawn mice. Thus, repeated diazepam administration during the alcohol-withdrawal period only transitorily canceled out the working memory impairments and glucocorticoid alterations in the PFC of alcohol-withdrawn animals.

Baclofen but Not Diazepam Alleviates Alcohol-Seeking Behavior and Hypothalamic-Pituitary-Adrenal Axis Dysfunction in Stressed Withdrawn Mice

This study compares the impact of repeated injections of baclofen (an agonist of GABA_B receptors) or diazepam (a benzodiazepine having an agonist action on GABA_A receptors) given during the alcohol-withdrawal period on the stress-induced restoration of alcohol-seeking behavior and hypothalamic-pituitary-adrenal (HPA) axis dysfunction after a long (4 weeks) abstinence. Thus, C57BL/6 mice were submitted to a 6-month alcohol consumption [12% volume/volume (v/v)] and were progressively withdrawn to water before testing. Diazepam (Valium^®, Roche) and baclofen (Baclofen^®, Mylan) were administered intraperitoneally for 15 consecutive days (1 injection/day) during the withdrawal period at decreasing doses ranging from 1.0 mg/kg (Day 15) to 0.25 mg/kg (Day 1) for diazepam and from 1.5 mg/kg (Day 15) to 0.37 mg/kg (Day 1) for baclofen. Alcohol-seeking behavior was evaluated by alcohol-place preference in an odor recognition task. In the stress condition, mice received three electric footshocks 45 min before behavioral testing. Blood was sampled immediately after behavioral testing, and plasma corticosterone concentrations were measured by commercial enzyme immunoassay kits. Results showed that non-stressed withdrawn mice did not exhibit alcohol-place preference or alteration of plasma corticosterone concentrations relative to water controls. After stress, however, withdrawn mice exhibited a significant alcohol-place preference and higher circulating corticosterone concentrations as compared to stressed water controls. Interestingly, repeated administration during the withdrawal phase of baclofen but not diazepam suppressed both the alcohol-place preference and normalized corticosterone levels in stressed withdrawn animals. In conclusion, this study evidences that a pre-treatment with baclofen but not with diazepam during the withdrawal phase normalized, even after a long period of abstinence, the HPA axis response to stress, which contributes to the long-term preventing effects of this compound on alcohol-seeking behavior.

Alcohol withdrawal induces long-lasting spatial working memory impairments: relationship with changes in corticosterone response in the prefrontal cortex

This study intends to determine whether long-lasting glucocorticoids (GCs) dysregulation in the prefrontal cortex (PFC) or the dorsal hippocampus (dHPC) play a causal role in the maintenance of working memory (WM) deficits observed after alcohol withdrawal. Here, we report that C57/BL6 male mice submitted to 6 months alcohol consumption (12 percent v/v) followed by 1 (1W) or 6 weeks (6W) withdrawal periods exhibit WM deficits in a spatial alternation task and an exaggerated corticosterone rise during and after memory testing in the PFC but not the dHPC. In contrast, emotional reactivity evaluated in a plus-maze is altered only in the 1W group. No behavioral alterations are observed in mice still drinking alcohol. To determine the causal role of corticosterone in the withdrawal-associated long-lasting WM deficits, we further show that a single intraperitoneal injection injection of metyrapone (an inhibitor of corticosterone synthesis) 30 minutes before testing, prevents withdrawal-associated WM deficits and reestablishes PFC activity, as assessed by increased phosphorylated C-AMP Response Element-binding protein (CREB) immunoreactivity in withdrawn mice. Finally, we show that intra-PFC blockade of mineralocorticoid receptors by infusion of spironolactone and, to a lesser extent, of GCs receptors by injection of mifepristone reverses the WM deficits induced by withdrawal whereas the same injections into the dHPC do not. Overall, our study evidences that long-lasting GCs dysfunction selectively in the PFC is responsible for the emergence and maintenance of WM impairments after withdrawal and that blocking prefrontal mineralocorticoid receptors receptors restores WM in withdrawn animals.

Cognitive Impairment and Tramadol Dependence

BACKGROUND AND OBJECTIVE

Cognitive impairment is one of the consequences of substance abuse. Tramadol abuse is a public health problem in Egypt. The objective of this study was to estimate the prevalence and correlates of cognitive impairment among tramadol-abuse patients and control subjects.

METHODS

This study included 100 patients with tramadol abuse and 100 control subjects (matched for age, sex, and education) who were recruited from Zagazig University Hospital, Egypt. Patients were divided into 2 groups: patients who used tramadol only (tramadol-alone group) and patients who used tramadol and other substances (polysubstance group). The participants were interviewed using Montreal Cognitive Assessment test and had urine screening for drugs.

RESULTS

Twenty-four percent of the cases used tramadol alone, whereas the remaining used tramadol and other substances, mainly cannabis (66%) and benzodiazepines (27%). Tramadol-abuse patients were about 3 times more likely to have cognitive impairment than control subjects (81% vs 28%). Tramadol-alone patients were more than 2 times more likely to have cognitive impairment than control subjects (67% vs 28%). Cognitive impairment was significantly associated with polysubstance abuse. There was no association between cognitive impairment and sociodemographic or clinical factors.

CONCLUSIONS

Cognitive impairment occurs commonly among tramadol-abuse patients. Memory impairment is the most common cognitive domain to be affected. There is a significant association between cognitive impairment and polysubstance abuse.

Volume of hippocampal subfields in patients with alcohol dependence

Alcohol-induced hippocampal atrophy has been well documented in many studies and is known to affect various subfields. Given the functional heterogeneity of these subfields, we investigated the precise effects of alcohol-induced damage in these areas. Twenty-six male patients with alcohol dependence (alcohol group) and twenty-six age-matched male healthy social drinkers were recruited from a mental health hospital and the community respectively, with the aim of comparing the hippocampal subfields between groups. Each participant underwent a 3T MRI scan. Hippocampal subfield volumes were estimated using an automated procedure and drinking history recorded using Lifetime Drinking History, Alcohol Use Disorder Identification Test, and the Brief Michigan Alcoholism Screening Test. The alcohol group showed a lower total hippocampus volume, specifically in the left presubiculum, fimbria, and bilateral subiculum. Regression analysis assessing the influence of age and group showed that group was a more significant factor than age in most subfields. Our findings suggest that alcohol dependence alters hippocampal subfield volumes. Further longitudinal studies on the interaction of structural and neurocognitive changes would improve our understanding of brain structural changes resulting from long-term alcohol consumption.

Learning and Memory Performance After Withdrawal of Agent Abuse: A Review

Context

Agent abuse is a dire predicament worldwide. Learning and memory deficits stemming from the withdrawal of such agents is an increasingly burning issue for researchers.

Evidence Acquisition

The present review revisits the literature generated by far pertaining to the research on memory and cognition deficiencies after withdrawal of agent abuse and corresponding mechanisms.

Results

Deficiency on spatial memory, episodic memory and working memory are common after withdrawal of agent abuse.

Conclusions

The present review suggests that memory dysfunction may result from withdrawal of agent abuse.

Double-blind, 12 month follow-up, placebo-controlled trial of mifepristone on cognition in alcoholics: the MIFCOG trial protocol

BACKGROUND

Increased levels of cortisol during acute alcohol withdrawal have been linked to cognitive deficits and depression. Preclinical research found that the glucocorticoid Type II receptor antagonist, mifepristone, prevented some of the neurotoxic effects of withdrawal and memory loss. Clinical trials have shown mifepristone effective in the treatment of depression. This study aims to examine the extent to which the glucocorticoid Type II receptor antagonist, mifepristone, when given to alcohol dependent males during the acute phase of alcohol withdrawal, will protect against the subsequent memory loss and depressive symptoms during abstinence from alcohol.

METHODS/DESIGN

The study is a Phase 4 therapeutic use, "Proof of Concept" trial. The trial is a double-blind randomised controlled clinical trial of mifepristone versus inactive placebo. The trial aims to recruit 120 participants referred for an inpatient alcohol detoxification from community alcohol teams, who meet the inclusion criteria; 1) Male, 2) Aged 18-60 inclusive, 3) alcohol dependent for 5 or more years. A screening appointment will take place prior to admission to inpatient alcohol treatment units to ensure that the individual is suitable for inclusion in the trial in accordance with the inclusion and exclusion criteria. On admission participants are randomised to receive 600 mg a day of mifepristone (200 mg morning, afternoon and evening) for 7 days and 400 mg for the subsequent 7 days (200 mg morning and evening) or the equivalent number of placebo tablets for 14 days. Participants will remain in the trial for 4 weeks (at least 2 weeks as an inpatient) and will be followed up at 3, 6 and 12 months post randomisation. Primary outcome measures are cognitive function at week 3 and 4 after cessation of drinking and symptoms of depression over the 4 weeks after cession of drinking, measured using the Cambridge Neuropsychological Test Automated battery and Beck Depression Inventory, respectively. Secondary outcome measures are severity of the acute phase of alcohol withdrawal, alcohol craving, symptoms of protracted withdrawal and maintenance of abstinence and levels of relapse drinking at follow-up.

DISCUSSION

The current trial will provide evidence concerning the role of glucocorticoid Type II receptor activation in cognitive function and depression during acute alcohol withdrawal and the efficacy of treatment with mifepristone.

ISRCTN

ISRCTN54001953, Registered 29th September 2011.

Visual and verbal learning deficits in Veterans with alcohol and substance use disorders

BACKGROUND

This study examined visual and verbal learning in the early phase of recovery for 48 Veterans with alcohol use (AUD) and substance use disorders (SUD, primarily cocaine and opiate abusers). Previous studies have demonstrated visual and verbal learning deficits in AUD, however little is known about the differences between AUD and SUD on these domains. Since the DSM-5 specifically identifies problems with learning in AUD and not in SUD, and problems with visual and verbal learning have been more prevalent in the literature for AUD than SUD, we predicted that people with AUD would be more impaired on measures of visual and verbal learning than people with SUD.

METHODS

Participants were enrolled in a comprehensive rehabilitation program and were assessed within the first 5 weeks of abstinence. Verbal learning was measured using the Hopkins Verbal Learning Test (HVLT) and visual learning was assessed using the Brief Visuospatial Memory Test (BVMT).

RESULTS

Results indicated significantly greater decline in verbal learning on the HVLT across the three learning trials for AUD participants but not for SUD participants (F=4.653, df=48, p=0.036). Visual learning was less impaired than verbal learning across learning trials for both diagnostic groups (F=0.197, df=48, p=0.674); there was no significant difference between groups on visual learning (F=0.401, df=14, p=0.538).

DISCUSSION

Older Veterans in the early phase of recovery from AUD may have difficulty learning new verbal information. Deficits in verbal learning may reduce the effectiveness of verbally-based interventions such as psycho-education.

Contribution of Regional White Matter Integrity to Visuospatial Construction Accuracy, Organizational Strategy, and Memory for a Complex Figure in Abstinent Alcoholics

Visuospatial construction ability as used in drawing complex figures is commonly impaired in chronic alcoholics, but memory for such information can be enhanced by use of a holistic drawing strategy during encoding. We administered the Rey-Osterrieth Complex Figure Test (ROCFT) to 41 alcoholic and 38 control men and women and assessed the contribution of diffusion tensor imaging (DTI) measures of integrity of selected white matter tracts to ROCFT copy accuracy, copy strategy, and recall accuracy. Although alcoholics copied the figure less accurately than controls, a more holistic strategy at copy was associated with better recall in both groups. Greater radial diffusivity, reflecting compromised myelin integrity, in occipital forceps and external capsule was associated with poorer copy accuracy in both groups. Lower FA, reflecting compromised fiber microstructure in the inferior cingulate bundle, which links frontal and medial temporal episodic memory systems, was associated with piecemeal copy strategy and poorer immediate recall in the alcoholics. The correlations were generally modest and should be considered exploratory. To the extent that the inferior cingulate was relatively spared in alcoholics, it may have provided an alternative pathway to the compromised frontal system for successful copy strategy and, by extension, aided recall.

Rapid cognitive screening of patients with substance use disorders

To date, there has not been a time-efficient and resource-conscious way to identify cognitive impairment in patients with substance use disorders (SUDs). In this study, we assessed the validity, accuracy, and clinical utility of a brief (10-min) screening instrument, the Montreal Cognitive Assessment (MoCA), in identifying cognitive impairment among patients with SUDs. The Neuropsychological Assessment Battery-Screening Module, a 45-min battery with known sensitivity to the mild to moderate deficits observed in patients with SUDs, was used as the reference criterion for determining agreement, rates of correct and incorrect decision classifications, and criterion-related validity for the MoCA. Classification accuracy of the MoCA, based on receiver operating characteristic (ROC) analysis, was strong, with an area under the ROC curve of 0.86, 95% confidence interval [0.75, 0.97]. The MoCA also showed acceptable sensitivity (83.3%) and specificity (72.9%) for the identification of cognitive impairment. Using a cutoff of 25 on the MoCA, the overall agreement was 75.0%; chance-corrected agreement (kappa) was 41.9%. These findings indicate that the MoCA provides a time-efficient and resource-conscious way to identify patients with SUDs and neuropsychological impairment, thus addressing a critical need in the addiction treatment research community.

Effects of the glucocorticoid antagonist, mifepristone, on the consequences of withdrawal from long term alcohol consumption

BACKGROUND

Studies were carried out to test the hypothesis that administration of a glucocorticoid Type II receptor antagonist, mifepristone (RU38486), just prior to withdrawal from chronic alcohol treatment, would prevent the consequences of the alcohol consumption and withdrawal in mice.

MATERIALS AND METHODS

The effects of administration of a single intraperitoneal dose of mifepristone were examined on alcohol withdrawal hyperexcitability. Memory deficits during the abstinence phase were measured using repeat exposure to the elevated plus maze, the object recognition test, and the odor habituation/discrimination test. Neurotoxicity in the hippocampus and prefrontal cortex was examined using NeuN staining.

RESULTS

Mifepristone reduced, though did not prevent, the behavioral hyperexcitability seen in TO strain mice during the acute phase of alcohol withdrawal (4 hours to 8 hours after cessation of alcohol consumption) following chronic alcohol treatment via liquid diet. There were no alterations in anxiety-related behavior in these mice at 1 week into withdrawal, as measured using the elevated plus maze. However, changes in behavior during a second exposure to the elevated plus maze 1 week later were significantly reduced by the administration of mifepristone prior to withdrawal, indicating a reduction in the memory deficits caused by the chronic alcohol treatment and withdrawal. The object recognition test and the odor habituation and discrimination test were then used to measure memory deficits in more detail, at between 1 and 2 weeks after alcohol withdrawal in C57/BL10 strain mice given alcohol chronically via the drinking fluid. A single dose of mifepristone given at the time of alcohol withdrawal significantly reduced the memory deficits in both tests. NeuN staining showed no evidence of neuronal loss in either prefrontal cortex or hippocampus after withdrawal from chronic alcohol treatment.

CONCLUSIONS

The results suggest mifepristone may be of value in the treatment of alcoholics to reduce their cognitive deficits.

Neurocognitive function in monozygotic twins discordant for combat exposure: relationship to posttraumatic stress disorder

Neuropsychological deficits have been reported among trauma survivors with posttraumatic stress disorder (PTSD). It is often assumed that these cognitive difficulties are toxic consequences of trauma exposure. Alternatively, they may reflect preexisting characteristics that contribute to the likelihood of developing PTSD. To address this possibility, the authors evaluated cognitive performance in monozygotic twin pairs who were discordant for combat exposure. Pairs were grouped according to whether the combat-exposed brother developed PTSD. The combat-unexposed cotwins of combat veterans with PTSD largely displayed the same performance as their brothers, which was significantly lower than that of non-PTSD combat veterans and their brothers. The results support the notion that specific domains of cognitive function may serve as premorbid risk or protective factors in PTSD.

The effect of relapse on cognition in abstinent methamphetamine abusers

Data from 75 participants in a longitudinal study of methamphetamine (MA) abuse were used to differentiate the cognitive performance of those who remained abstinent, relapsed, or continued to use during treatment. Participants were divided into three groups: continuous abstinence, initial abstinence but relapse, and continuous use. Groups did not differ on age, education, gender or ethnicity. Participants in the longitudinal study completed a battery of cognitive tests within 7 days of their last use of MA, then were re-tested monthly for up to 6 months (average time for this analysis was 92 days). For episodic memory, the relapse groups performance was worse than the abstinent and significantly worse than that of the continued use group who had the best performance on all measures. Relapse to methamphetamine use may affect episodic memory differently than it affects the other cognitive functions measured.

Alcohol, estrogen replacement therapy, and visuospatial processes in postmenopausal women

BACKGROUND

Studies suggest that moderate drinking may benefit cognition and the effect may favor women. This study investigated effects of moderate drinking on visuospatial functioning in postmenopausal women. Visuospatial processes are sensitive to alcohol abuse and are thought to be sensitive to hormonal fluctuations. Three questions were posed in order to: explore visuospatial processes in moderate-drinking and abstaining postmenopausal women, assess visuospatial differences in women using no estrogen replacement therapy (No-ERT), ERT alone (ERT-only), and ERT with progestin (ERT+Pro), and identify alcohol/ERT interactions associated with visuospatial performance.

METHODS

Two hundred fourteen postmenopausal women participated (75 No-ERT; 63 ERT-only; 76 ERT+Pro. All were moderate drinkers or teetotalers and all received the Block Design test from the Wechsler Adult Intelligence Scale-Revised. A raw score was calculated and progress at 30-sec intervals was assessed.

RESULTS

ANOVA revealed an alcohol main effect [F(3,202) = 4.74; p < 0.004] on 60- to 120-sec change scores. Teetotalers had significantly smaller change scores (less improvement) compared with all levels of drinkers. ANOVA on design 9 (the most difficult trial) revealed an ERT main effect [F(3,202) = 4.37; p < 0.02]. ERT nonusers scored significantly lower than ERT-only and ERT+Pro groups. A design 9 trend toward an alcohol x ERT interaction was noted [F(6,202) = 1.93; p < 0.08], and a design 9 time x alcohol interaction was revealed [F(6,404) = 2.65; p < 0.02].

CONCLUSIONS

These data suggest that moderate drinking may be positively associated with visuospatial processes in postmenopausal women. They also suggest that ERT, alone and with progestin, is positively associated with visuospatial processes, but only when the task is difficult. These findings support Kaplan's assertion that subtle performance deficits may not be detectible with traditional endpoint measures. A provocative alcohol x ERT trend suggests that alcohol consumption should be considered in studies of ERT effects on cognitive ability.

Facial affect perception in alcoholics

Satisfactory interpersonal interaction involves understanding others' facial expressions. Alcoholic individuals often have severe interpersonal difficulties that may relate to poor and distorted perception of facial expressions. The importance of attention direction has been highlighted by the finding, in recent primate studies, of neurons responsible for the detection of attention direction. Studies on humans suggest that expression perception is modulated by attention direction (whether the expression is directed towards or away from the observer). Here, for the first time, the relationship between attention direction and perception of expression (anger, sadness, happiness and disgust) in alcoholic and control subjects is investigated. We used animated facial stimuli depicting different emotions to give measures of recognition accuracy and of perceptual sensitivity. Our study demonstrated that alcoholics made more errors than control subjects in recognising expressions generally and had a tendency to mis-label sad expressions directed towards them as being hostile (angry/disgusted). When asked to select the point when they started to see the expression, alcoholics, especially female alcoholics, chose higher expression intensities. This study highlights the importance of investigating the modulating effects of attention direction when studying the perception of expressions and provides an indication of how alcoholics' inappropriate social reactions may be triggered.

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.

Reduction in BOLD fMRI response to primary visual stimulation following alcohol ingestion

The physiology of alcohol's effects on brain function is poorly understood. Emission tomographic imaging has revealed both acute and chronic alterations in resting cerebral hemodynamics and metabolism following alcohol ingestion. However, cerebral functional integrity under these conditions has received less attention. Functional magnetic resonance imaging (fMRI) offers a non-invasive method for assessing brain functional activation. In order to assess its utility for studying the effect of alcohol on brain function, we performed fMRI with photic stimulation before and after administration of either 0.7 mg/kg alcohol (N = 12) or placebo (N = 5), resulting in peak breath alcohol levels averaging 0.069 g/dl. We found that the amplitude of visual cortical activation in response to photic stimulation was significantly reduced by approximately 33% following alcohol administration (4.0 +/- 1.7% vs. 2.7 +/- 1.3%, P = 0.02), but not following placebo (4.2 +/- 1.5% vs. 4.1 +/- 1.4%, P = 0.7). The results also suggest that the baseline right hemispheric predominance of activation in response to photic stimulation may be reduced following alcohol, suggesting a greater effect on the right hemisphere, consistent with previous studies and alcohol's known effects on visuospatial processing. In addition, through the course of each activation session, there was a progressive reduction in response following alcohol. These data demonstrate that the cerebral effects of alcohol intoxication can be studied with fMRI, and that the effects on brain function of even moderate alcohol intoxication may be widespread, may be lateralized, and may include the visual system.