Increases in ethanol ingestion by young rats following interaction with intoxicated siblings: A review

Although there are a variety of animal models used in alcoholism research, there has been very little experimental investigation into possible environmental/experiential factors leading to an initial bout of alcohol ingestion. Adolescent alcohol abuse is a major problem in today's society and research is beginning to focus on the predisposing conditions toward alcohol consumption, particularly in this vulnerable age group. The results of recent research from our laboratory are reviewed in which voluntary ingestion of ethanol by preweanling and adolescent rats is increased following exposure to an intoxicated sibling. This paradigm centers on the notion that rodents, and perhaps other mammalian species as well, acquire information about foods to ingest based in part on interaction with a conspecific that has recently ingested a novel diet (e.g. Galef, 1981). Smelling food-derived cues on the breath of another animal is known to affect later food choice. The procedures described in this paper represent a potential new model for examining the effects of early exposure to ethanol through social interactions on the initiation of voluntary alcohol ingestion.     

The Effects of Prenatal Alcohol Exposure on Behavior: Rodent and Primate Studies

The use of alcohol by women during pregnancy is a continuing problem. In this review the behavioral effects of prenatal alcohol from animal models are described and related to studies of children and adults with FASD. Studies with monkeys and rodents show that prenatal alcohol exposure adversely affects neonatal orienting, attention and motor maturity, as well as activity level, executive function, response inhibition, and sensory processing later in life. The primate moderate dose behavioral findings fill an important gap between human correlational data and rodent mechanistic research. These animal findings are directly translatable to human findings. Moreover, primate studies that manipulated prenatal alcohol exposure and prenatal stress independently show that prenatal stress exacerbates prenatal alcohol-induced behavioral impairments, underscoring the need to consider stress-induced effects in fetal alcohol research. Studies in rodents and primates show long-term effects of prenatal and developmental alcohol exposure on dopamine system functioning, which could underpin the behavioral effects.     

Positive correlation between measures of habitual responding and motivated responding in mice

Habit and motivation are thought to be separate processes, with motivated behavior often considered to be goal directed, whereas habits are defined by the absence of goal-directed control over behavior. However, there has been increasing interrogation of the binary nature of habitual versus goal-directed behavior. Furthermore, although drug and alcohol exposure can promote the formation of habits, drug seeking itself can also be highly flexible, pointing toward the need for complex consideration of the parallel processes that drive behavior. The goal of the current study was to determine whether there was a relation between motivation—as measured by progressive ratio—and habit—as measured by contingency degradation—and whether this relation was affected by ethanol exposure history and sex. The results showed that these measures were positively correlated such that greater contingency insensitivity was associated with achieving higher break points on the progressive-ratio task. However, this relation depended on reinforcement schedule history, ethanol exposure history, and sex. These point to potential relations between measures of habit and motivation and stress the importance of carefully parsing behavioral findings and assays. These findings are also expected to inform future substance use research, as drug history may affect these relations.     

Early (preweanling) recognition of alcohol's orosensory cues resulting from acute ethanol intoxication

Three experiments were conducted in order to analyze the possibility that during acute alcohol intoxication, preweanling rats process ethanol's orosensory cues. Intragastric administration of an ethanol dose equivalent to 3.0 g/kg resulted in peak blood alcohol levels greater than 250 mg% (Experiment 1). Twenty-four hours after receiving this dose, 11-day-old pups expressed an ethanol odor aversion in a locational test. This aversion response was not observed when pups were previously administered an ethanol dose resulting in blood alcohol levels lower than 150 mg% (Experiment 2). Nevertheless when subjects received such a lower dose and 30 to 60 min after administration suffered nociceptive stimulation, alcohol aversions were also detected in terms of alcohol ingestion patterns and ethanol odor aversions (Experiment 3). These results appear to indicate that orosensory ethanol processing takes place during acute ethanol intoxication probably due to ethanol elimination via respiration, salivation, and/or hematogenic olfaction processes.     

The impact of emotional stress early in life on adult voluntary ethanol intake-results of maternal separation in rats

The combination of genetic and environmental factors determines the individual vulnerability for excessive ethanol intake, possibly leading to dependence. The environmental influences early in life represent examples of determinant factors for adult behaviour and can be protective as well as risk factors. Maternal separation is one model to examine the long-term consequences of early environmental experiences on neurochemistry and behaviour, including drug-taking behaviour in experimental animals. In the present review, findings from studies using repeated short and prolonged periods of maternal separation, with emphasis on effects on voluntary ethanol intake in rats with or without a genetic predisposition for high voluntary ethanol intake, are summarized. Despite some contradictory results, the general picture emerging shows that short periods of maternal separation during the postnatal period result in a lower adult voluntary ethanol intake in male rats. Prolonged periods of maternal separation were found to induce a high voluntary ethanol intake in male rats, including rats with a genetic predisposition for high ethanol intake. Results from the literature also show that changes were not just related to time of separation but were also related to the degree of handling. Interestingly, in terms of voluntary ethanol intake, female rats were generally not affected by postnatal maternal separation. The reasons for these sex differences need further investigation. In terms of neurobiological consequences of maternal separation, conclusive data are sparse and one of the future challenges will, therefore, be to identify and characterize underlying neurobiological mechanisms, especially in the individual animal.     

Weanlings' transfer of conditioned ethanol aversion from olfaction to ingestion depends on the unconditioned stimulus

Weanling (21-day-old) rats were exposed to an alcohol odor paired with either an interoceptive (apomorphine-induced illness) or exteroceptive (footshock-induced distress) reinforcer. Twenty-four hours later, ethanol preferences were measured in a locational olfactory test (ethanol vs lemon odor) or an ingestion test (5.6% v/v ethanol vs 0.25% v/v citric acid solution). Weanling rats expressed substantial olfactory aversions, independent of the reinforcer employed in conditioning. During the drinking test, however, only rats that had experienced the ethanol odor paired with internal malaise showed a significant reduction in the intake of the ethanol solution when compared to unpaired controls. Furthermore, rats that had experienced the ethanol odor paired with external distress drank significantly more of the ethanol solution than their controls. These results provide further evidence that olfactory experiences with ethanol can lead to changes in ethanol ingestion, and indicate that the nature of the unconditioned stimulus is critical in establishing the ingestive effect.     

A behavioural-pharmacological treatment of dually addicted patients

maintenance appears to be an effective means of treating narcotic addiction both because it blocks the effects of heroin and because patients are willing to accept methadone treatment. However, alcoholism has been found commonly to complicate methadone maintenance and to result in treatment failure. The regular ingestion of disulfiram, a drug which blocks ethanol metabolism, could provide a solution to this problem, but alcoholics tend not to persist in taking this drug, because unlike methadone it possesses no reinforcing properties. This paper describes a novel technique whereby the reinforcing action of methadone has been employed to maintain disulfiram-taking, and thus to arrest alcohol abuse and consequent treatment failure.     

Fetal Alcohol Spectrum Disorders: Neuropsychological and Behavioral Features

Heavy prenatal alcohol exposure can cause alterations to the developing brain. The resulting neurobehavioral deficits seen following this exposure are wide-ranging and potentially devastating and, therefore, are of significant concern to individuals, families, communities, and society. These effects occur on a continuum, and qualitatively similar neuropsychological and behavioral features are seen across the spectrum of effect. The term fetal alcohol spectrum disorders (FASD) has been used to emphasize the continuous nature of the outcomes of prenatal alcohol exposure, with fetal alcohol syndrome (FAS) representing one point on the spectrum. This paper will provide a comprehensive review of the neuropsychological and behavioral effects of heavy prenatal alcohol exposure, including a discussion of the emerging neurobehavioral profile. Supporting studies of lower levels of exposure, brain-behavior associations, and animal model systems will be included when appropriate.     

THE RELATIONSHIP BETWEEN OPINION LEADERSHIP AND INFORMATION ACQUISITION

Previous research has demonstrated that opinion leaders consistently have more information on the topic of their leadership than do non-opinion leaders. This study tested two theoretical explanations for this phenomenon: selectivity in exposure to information, and differential attention to information. The results provide support for both explanations. Opinion leaders were found to acquire more information than non-opinion leaders under conditions of both voluntary and forced exposure to a mediated message. Both opinion leaders and non-opinion leaders acquired more information under forced exposure than under voluntary exposure.     

Influence of rearing conditions on voluntary ethanol intake and response to stress in rats

The effects of exposure to four environmental rearing conditions on subsequent voluntary ethanol intake and response to immobilization stress were examined. Male weanling rats were reared in an enriched environment, with a female partner, with a male partner, or individually, for 90 days. At 111 days of age, voluntary consumption of ethanol in increasing concentrations (3 to 9%, v/v) was assessed. Following the ethanol-exposure period, rats were randomly divided into stressed and nonstressed groups and exposed to 3 h of immobilization. Results indicated that the enriched animals consumed greater amounts of ethanol as compared to all other groups, suggesting that the enriched environment and not handling, housing conditions, or the presence of another male or female is responsible for the observed increase in ethanol drinking behavior. Ulcer data indicated that among environmentally enriched rats, ethanol attenuated stress ulcer development relative to their non-ethanol-exposed but stressed controls. In nonstressed enriched rats, ethanol alone exacerbated stomach damage. We suggest that environmental rearing conditions markedly influence the complex interaction between ethanol intake and the response to stress.     

Formula: see text]Substance exposure in utero and developmental consequences in adolescence: A systematic review

Background: The impacts of maternal substance use have been observed in both research and clinical experience. Several studies have shown that preschool children are at heightened risk of developing various cognitive, behavioral, and socioemotional difficulties. Most knowledge has been generated concerning alcohol consumption during pregnancy and the postnatal effects thereof. Less is known about substance use other than alcohol (for instance, opiates, marijuana, and cocaine) during pregnancy and the long-term developmental consequences. Objective: The aims of this review are to identify relevant published data on adolescents who have been exposed in utero to alcohol and/or other substances and to examine developmental consequences across functions and mental health at this point in life. Methods: PubMed, Embase, and PsychInfo were searched for publications during the period of 1980-2011 and titles and abstracts selected according to prespecified broad criteria. Results: Twenty-five studies fulfilled all of the specific requirements and were included in this review. Most research covered prenatal alcohol exposure. Other substances, however, included cocaine, marijuana, opiates, and poly-substances. Results showed that prenatal exposure to alcohol has long-term cognitive, behavioral, social, and emotional developmental consequences depending on amount and timing of exposure in utero. Less evidence exists for long-term consequences of exposure in utero to other substances than alcohol. However, recent brain-imaging studies have provided important evidence of serious effects of other substance exposure on the developing brain and recent follow-up studies have found an association with deficits in language, attention, areas of cognitive performance and delinquent behavior in adolescence.     

An appraisal of chemical aversion (emetic therapy) approaches to alcoholism treatment.

More than 35,000 alcoholics have received chemical aversion (emetic therapy) in at least 75 settings worldwide since the 1930s. This consummatory aversion (CA) treatment, which pairs ethanol ingestion with emetically induced nausea, incorporates the highly efficient variety of learning known as taste aversion (TA) conditioning. The CA literature indicates that emetic therapy should induce conditioned alcohol aversions in many alcoholics. Such aversions have been widely reported by clinicians and have been confirmed by recent psychophysiological evidence. Long standing evidence of treatment effectiveness is found in the results of private hospitals which have consistently produced 1-yr abstinence rates approximating 60%. Diminished alcohol craving is a frequently reported benefit. Few experimental evaluations have been completed, as is generally the case for all alcoholism treatments, but those which used methodologically sound temporal parameters during conditioning have supported the clinical efficacy of emetic therapy. The clear need for more definitive research notwithstanding, there are compelling indications that emetic therapy is a useful component of multimodal treatment within certain alcoholic populations. However, its availability is severely limited. Many alcoholics could probably benefit from expanded treatment availability. The time is ripe for a reevaluation of resistances to the clinical use of emetic therapy alcoholism treatment.     

Acute Alcohol Co‐Ingestion and Hospital‐Treated Deliberate Self‐Poisoning: Is There an Effect on Subsequent Self‐Harm?

The aim of this study was to determine the relationship between alcohol co‐ingestion in an index deliberate self‐poisoning (DSP) episode with repeated DSP and subsequent suicide. A retrospective cohort study was conducted involving 5,669 consecutive index presentations to a toxicology service following DSP between January 1, 1996, and October 31, 2010. Records were probabilistically matched to National Coronial Information System data to identify subsequent suicide. Index DSPs were categorized on co‐ingestion of alcohol, and primary outcomes analyzed were repetition of any DSP, rates of repeated DSP, time to first repeat DSP, and subsequent suicide. Co‐ingestion of alcohol occurred in 35.9% of index admissions. There was no difference between those who co‐ingested alcohol (ALC+) and those who did not co‐ingest alcohol (ALC?) in terms of proportion of repeat DSP, number of DSP events, or time to first repeat DSP event. Forty‐one (1.0%) cases were probabilistically matched to a suicide death; there was no difference in the proportion of suicide between ALC+ and ALC? at 1 or 3 years. There was no significant relationship between the co‐ingestion of alcohol in an index DSP and subsequent repeated DSP or suicide. Clinically, this highlights the importance of mental health assessment of patients that present after DSP, irrespective of alcohol co‐ingestion at the time of event.     

Alcohol-related amnesia and dementia: animal models have revealed the contributions of different etiological factors on neuropathology, neurochemical dysfunction and cognitive impairment

Chronic alcoholism is associated with impaired cognitive functioning. Over 75% of autopsied chronic alcoholics have significant brain damage and over 50% of detoxified alcoholics display some degree of learning and memory impairment. However, the relative contributions of different etiological factors to the development of alcohol-related neuropathology and cognitive impairment are questioned. One reason for this quandary is that both alcohol toxicity and thiamine deficiency result in brain damage and cognitive problems. Two alcohol-related neurological disorders, alcohol-associated dementia and Wernicke-Korsakoff syndrome have been modeled in rodents. These pre-clinical models have elucidated the relative contributions of ethanol toxicity and thiamine deficiency to the development of dementia and amnesia. What is observed in these models--from repeated and chronic ethanol exposure to thiamine deficiency--is a progression of both neural and cognitive dysregulation. Repeated binge exposure to ethanol leads to changes in neural plasticity by reducing GABAergic inhibition and facilitating glutamatergic excitation, long-term chronic ethanol exposure results in hippocampal and cortical cell loss as well as reduced hippocampal neurotrophin protein content critical for neural survival, and thiamine deficiency results in gross pathological lesions in the diencephalon, reduced neurotrophic protein levels, and neurotransmitters levels in the hippocampus and cortex. Behaviorally, after recovery from repeated or chronic ethanol exposure there is impairment in working or episodic memory that can recover with prolonged abstinence. In contrast, after thiamine deficiency there is severe and persistent spatial memory impairments and increased perseverative behavior. The interaction between ethanol and thiamine deficiency does not produce more behavioral or neural pathology, with the exception of reduction of white matter, than long-term thiamine deficiency alone.     

The effects of ethanol intoxication on phobic anxiety

Behavioral conceptions of alcohol abuse often include the hypothesis that drinking behavior is a negatively reinforced operant, with ethanol intoxication viewed as alleviating aversive environmental and internal states. This hypothesis has not been confirmed or refuted by previous studies which employed mild stressors and limited assessment methodology. In the present experiment, 22 patients with severe phobias approached their phobic animal under two consecutive conditions—first while sober and second after drinking either a placebo or an intoxicating dose of ethanol. The severe anxiety induced was assessed behaviorally, physiologically and by the patient's self-report of fear. The intoxicated patients did not experience decreased anxiety, tachycardia or avoidance, compared to the placebo group. These results have clinical implications and suggest the need to reconsider tension-reduction theories of alcohol abuse.     

Acute alcohol intoxication paired with aversive reinforcement: ethanol odor as a conditioned reinforcer in rat pups

Previous research has suggested that infant rats process ethanol sensory properties during acute alcohol intoxication. The present study was designed in order to examine if alcohol odor could act as an aversive conditioned stimulus after the organism experiences the state of intoxication paired with nociceptive stimulation (footshock). In a first experiment 11-day-old pups received intragastric alcohol administration (1.5 g/kg). At different postabsorptive intervals footshock was presented (0-30, 30-60, 60-90, or 90-120 min). An explicitly unpaired control group which experienced footshock prior to the state of intoxication was also employed. All animals were subsequently tested in terms of alcohol intake and ethanol locational odor preferences. Both assessments indicated that pups which were exposed to the unconditioned peripheral stimulus 30-60 min after receiving ethanol expressed strong alcohol aversions. In a second experiment pups were exposed to footshock during this postabsorptive interval. Twenty four hours later, pups experienced ambient ethanol odor paired with soft or rough texture surfaces. Differential texture aversions were registered in experimental animals when compared with controls which suffered the state of intoxication explicitly unpaired with footshock, or unpaired presentations of ethanol odor and the tactile stimuli under consideration. These results appear to support the hypothesis concerning orosensory processing during an acute state of intoxication. Additionally it seems that the hedonic value of sensory attributes of this drug varies as a function of associative processes occurring during such a state.     

Rhythmic entrainment: Why humans want to,fireflies can’t help it,pet birds try,and sea lions have to be bribed

Until recently, the literature on rhythmic ability took for granted that only humans are able to synchronize body movements to an external beat—to entrain. This assumption has been undercut by findings of beat-matching in various species of parrots and, more recently, in a sea lion, several species of primates, and possibly horses. This throws open the question of how widespread beat-matching ability is in the animal kingdom. Here we reassess the arguments and evidence for an absence of beat-matching in animals, and conclude that in fact no convincing case against beat-matching in animals has been made. Instead, such evidence as there is suggests that this capacity could be quite widespread. Furthermore, mutual entrainment of oscillations is a general principle of physical systems, both biological and nonbiological, suggesting that entrainment of motor systems by sensory systems may be a default rather than an oddity. The question then becomes, not why a few privileged species are able to beat-match, but why species do not always do so—why they vary in both spontaneous and learned beat-matching. We propose that when entrainment is not driven by fixed, mandatory connections between input and output (as in the case of, e.g., fireflies entraining to each others’ flashes), it depends on voluntary control over, and voluntary or learned coupling of, sensory and motor systems, which can paradoxically lead to apparent failures of entrainment. Among the factors that affect whether an animal will entrain are sufficient control over the motor behavior to be entrained, sufficient perceptual sophistication to extract the entraining beat from the overall sensory environment, and the current cognitive state of the animal, including attention and motivation. The extent of entrainment in the animal kingdom potentially has widespread implications, not only for understanding the roots of human dance, but also for understanding the neural and cognitive architectures of animals.     

Job Embeddedness in a Culturally Diverse Environment

The demographic composition of the workforce is changing, with an increase in the participation of minorities. Numerous studies center their attention on the inclusion of minorities, but variation in turnover of a culturally diverse workforce has not received much attention. Forecasts indicate that by 2020 Hispanic presence will increase 60% nationwide. Given these trends, it is critical that management scholars examine the impact of Hispanic cultural factors on important organizational outcomes such as voluntary turnover. This paper assesses whether there are significant differences between Hispanics and Caucasians with respect to job embeddedness and voluntary turnover. The findings suggest that job embeddedness is a robust predictor of employee retention across diverse populations. Portions of this research were submitted by Carlos M. Mallol in partial fulfillment of requirements for his doctoral degree. A preliminary version of this article was presented at the 2003 Academy of International Business Conference.     

Effects of exposure to alcohol‐related cues on racial discrimination

Prior research has shown that exposure to alcohol‐related images exacerbates expression of implicit racial biases, and that brief exposure to alcohol‐related words increases aggressive responses. However, the potential for alcohol cue exposure to elicit differential aggression against a Black (outgroup) relative to a White (ingroup) target—that is, racial discrimination—has never been investigated. Here, we found that White participants (N = 92) exposed to alcohol‐related words made harsher judgments of a Black experimenter who had frustrated them than participants who were exposed to nonalcohol words. These findings suggest that exposure to alcohol cues increases discriminatory behaviors toward Blacks.     

Forgetting, preconditioning CS familiarization and taste aversion learning: An animal experiment with implications for alcoholism treatment

The rapid taste aversion acquisition, which typically occurs in many species when ingestion of a novel flavor precedes gastrointestinal distress, is retarded by preconditioning familiarity with the CS flavor. This CS familiarity effect (CSFE) might contraindicate taste aversion approaches to alcoholism treatment since alcoholics are quite accustomed to the tastes of alcoholic beverages. However, many alcoholics do develop strong nausea—induced alcohol aversions under appropriate conditioning parameters. Additionally, the CSFE is attenuated in rats by repeated conditioning trials including discrimination training. The present animal experiment was conducted to determine if the CSFE could additionally be weakened by process of forgetting, i.e. by preconditioning withdrawal of a familiar flavor analogous to an alcoholic's ‘drying out’ before psychotherapeutic intervention. Using saccharin as the CS flavor and cyclophosphamide as the conditioning agent, Sprague-Dawley derived rats acquired no aversions when conditioning was attempted immediately after flavor familiarization. However, significant and equivalent saccharin aversions were observed when conditioning was delayed for either 20 or 100 days after familiarization. These findings imply that the efficiency and cost effectiveness of taste aversion approaches to alcoholism treatment might be enhanced by a pretreatment period of abstinence from alcohol ingestion.