Supplemental taurine during adolescence and early adulthood has sex-specific effects on cognition, behavior and neurotransmitter levels in C57BL/6J mice dependent on exposure window.

The mammalian brain goes through final maturation during late adolescence and early adulthood with sex differences in timing. The key cellular processes, including changes in neurotransmitter receptor density and synaptic pruning, make this age uniquely vulnerable to neurotoxic insults. Teenagers and young adults are the major consumers of energy drinks, which contain high levels of taurine and caffeine. Taurine is one of the most abundant amino acids in the central nervous system, but the effects of supplemental taurine consumption during adolescence has not been well studied. We conducted an initial short-term exposure study with 0.12% taurine in drinking water and a long-term exposure dose-response study using 0.06 and 0.12% taurine in male and female C57BL/6J mice. We examined a broad range of cognitive functions and behaviors and measured neurotransmitter levels. We found no significant differences in anxiety, open field locomotor activity, or sensorimotor gating. However, we found impairments in novel object recognition and sex differences in Morris water maze. When taurine treatment stopped before behavioral experiments began, male mice had significant impairments in spatial learning and memory. In the dose-response study when taurine treatment continued throughout behavioral experiments, females had significant impairments. We also found sex differences in neurotransmitter levels with females having higher levels of glutamate, DOPAC and 5-HIAA. We conclude that both females and males are at risk from excess taurine consumption during final brain maturation.

Automated assessment of alcohol-induced impairment of balance in male and female social drinkers.

The acute administration of alcohol reliably impairs the ability to balance when standing. The standardized field sobriety test uses alcohol-induced impairment of body stability to indicate probable alcohol intoxication. Given that body sway is used in the detection of alcohol impairment and intoxication, it is surprising that little research with humans has incorporated new technology that provides automated neuromuscular control assessment. Therefore, the purpose of this study was to examine the dose response to the acute effects of alcohol below and at the legal limit for driving in the United States on balance impairments, as measured by the Biosway Portable Balance System (Biodex Medical Systems, Inc.). Fourteen social drinkers attended 3 separate sessions during which they received alcohol (0.0, 0.3, and 0.6 g/kg alcohol). Body sway with eyes open and eyes closed was assessed at 45 min after dose administration when breath alcohol concentration was peaking for both active alcohol doses (.04g% and .08g%). The results indicated that body sway was significantly increased in the 0.6 g/kg alcohol conditions when compared with the placebo and 0.3 g/kg alcohol conditions. Body sway was not significantly elevated in the 0.3 g/kg alcohol condition compared with placebo. The results from this study suggest that this new technology may be of interest to alcohol researchers and the police as a more precise assessment of balance. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Is (poly-) substance use associated with impaired inhibitory control? A mega-analysis controlling for confounders.

Many studies have reported that heavy substance use is associated with impaired response inhibition. Studies typically focused on associations with a single substance, while polysubstance use is common. Further, most studies compared heavy users with light/non-users, though substance use occurs along a continuum. The current mega-analysis accounted for these issues by aggregating individual data from 43 studies (3610 adult participants) that used the Go/No-Go (GNG) or Stop-signal task (SST) to assess inhibition among mostly "recreational" substance users (i.e., the rate of substance use disorders was low). Main and interaction effects of substance use, demographics, and task-characteristics were entered in a linear mixed model. Contrary to many studies and reviews in the field, we found that only lifetime cannabis use was associated with impaired response inhibition in the SST. An interaction effect was also observed: the relationship between tobacco use and response inhibition (in the SST) differed between cannabis users and non-users, with a negative association between tobacco use and inhibition in the cannabis non-users. In addition, participants' age, education level, and some task characteristics influenced inhibition outcomes. Overall, we found limited support for impaired inhibition among substance users when controlling for demographics and task-characteristics.

Differential development of acute tolerance may explain heightened rates of impaired driving after consumption of alcohol mixed with energy drinks versus alcohol alone.

Consumers of alcohol mixed with energy drinks (AmED) are more likely to drive while impaired when compared to alcohol alone consumers. In addition, acute tolerance to the internal cues of feelings of intoxication is known to contribute to maladaptive decisions to drive while impaired. Therefore, the purpose of this study was to determine whether there is differential development of acute tolerance for AmED versus alcohol alone for ratings of willingness to drive after alcohol consumption. Social drinkers (n = 12) attended 4 separate sessions where they received alcohol and energy drinks, alone and in combination. The development of acute tolerance to alcohol was assessed for several objective (a computerized cued go/no-go reaction time task) and subjective measures at matched breath alcohol concentrations (BrACs) for the ascending and descending limbs of the BrAC curve. The results indicated that alcohol administration decreased willingness to drive ratings. Acute tolerance was observed in the AmED dose condition for only the willingness to drive ratings that were significantly higher on the descending versus ascending test. Alcohol-induced impairments of the computer task performance did not exhibit any acute tolerance. Therefore, the differential development of acute tolerance may explain why many studies observe higher rates of impaired driving for AmED consumers compared to alcohol alone consumers. Because drunk driving is a major public health concern, alcohol consumers should be warned that the use of energy drink mixers with alcohol could lead to a false sense of security in one's ability to drive after drinking. (PsycINFO Database Record

Alcohol-Induced Impairment of Balance is Antagonized by Energy Drinks.

BACKGROUND: The acute administration of alcohol reliably impairs balance and motor coordination. While it is common for consumers to ingest alcohol with other stimulant drugs (e.g., caffeine, nicotine), little is known whether prototypical alcohol-induced balance impairments are altered by stimulant drugs. The purpose of this study was to examine whether the coadministration of a high-caffeine energy drink with alcohol can antagonize expected alcohol-induced increases in body sway. METHODS: Sixteen social drinkers (of equal gender) participated in 4 separate double-blind dose administration sessions that involved consumption of alcohol and energy drinks, alone and in combination. Following dose administration, participants completed automated assessments of balance stability (both eyes open and eyes closed) measured using the Biosway Portable Balance System. Participants completed several subjective measures including self-reported ratings of sedation, stimulation, fatigue, and impairment. Blood pressure and pulse rate were recorded repeatedly. RESULTS: The acute administration of alcohol increased body sway, and the coadministration of energy drinks antagonized this impairment. When participants closed their eyes, alcohol-induced body sway was similar whether or not energy drinks were ingested. While alcohol administration increased ratings of sedation and fatigue, energy drink administration increased ratings of stimulation and reduced ratings of fatigue. Modest increases in systolic and diastolic blood pressure following energy drink administration were also observed. CONCLUSIONS: Visual assessment of balance impairment is frequently used to indicate that an individual has consumed too much alcohol (e.g., as part of police-standardized field sobriety testing or by a bartender assessing when someone should no longer be served more alcohol). The current findings suggest that energy drinks can antagonize alcohol-induced increases in body sway, indicating that future work is needed to determine whether this observation regarding neuromotor functioning applies to alcohol in combination with all types of stimulant drugs.

Taurine, caffeine, and energy drinks: Reviewing the risks to the adolescent brain.

Energy drinks are emerging as a major component of the beverage market with sales projected to top $60 billion globally in the next five years. Energy drinks contain a variety of ingredients, but many of the top-selling brands include high doses of caffeine and the amino acid taurine. Energy drink consumption by children has raised concerns, due to potential caffeine toxicity. An additional risk has been noted among college-aged consumers of energy drinks who appear at higher risk of over-consumption of alcohol when the two drinks are consumed together. The differential and combinatorial effects of caffeine and taurine on the developing brain are reviewed here with an emphasis on the adolescent brain, which is still maturing. Key data from animal studies are summarized to highlight both reported benefits and adverse effects reported following acute and chronic exposures. The data suggest that age is an important factor in both caffeine and taurine toxicity. Although the aged or diseased brain might benefit from taurine or caffeine supplementation, it appears that adolescents are not likely to benefit from supplementation and may, in fact, suffer ill effects from chronic ingestion of high doses. Additional work is needed though to address gaps in our understanding of how taurine affects females, since the majority of animal studies focused exclusively on male subjects.

How actions taken (or not) under alcohol influence inhibitory control and perceived impairment.

Consumption of alcohol can lead to the impairment of the ability to suppress inappropriate responses. However, alcohol-induced disinhibition does not occur in all contexts in the real world. Therefore, the purpose of this study was to examine if actions taken (or not) under alcohol will impact observed inhibitory control and how behavioral control requirements under alcohol alter perceived levels of impairment. Participants (n = 40) of equal sex who were social drinkers participated in a 3 session laboratory study that involved the administration of placebo, 0.45g/kg, and 0.65g/kg doses of alcohol. Participants were randomly assigned to a modified cued go/no-go reaction time (RT) task that included more go trials (activational condition) or more no-go trials (inhibitory condition). On all sessions after dose administration, participants completed their assigned cued go/no-go computer task and gave subjective ratings of impairment. The results indicated that participants in the activational condition under all doses of alcohol, but particularly the highest dose of alcohol, displayed poorer behavioral control (i.e., greater inhibitory failures) but self-reported lower perceived impairment, when compared to participants in the inhibitory condition. Therefore, this study provides laboratory evidence that alcohol consumption in an active setting will lead to greater disinhibition and reduced perceptions of impairment of behavior. The findings highlight the importance of the drinking setting when examining the acute effects of alcohol and suggest potential avenues for harm reduction for individuals who have difficulty controlling their alcohol intake. (PsycINFO Database Record

Effects of Energy Drinks on Economy and Cardiovascular Measures.

Peveler, WW, Sanders, GJ, Marczinski, CA, and Holmer, B. Effects of energy drinks on economy and cardiovascular measures. J Strength Cond Res 31(4): 882-887, 2017-The use of energy drinks among athletes has risen greatly. Caffeine and taurine are the 2 primary performance enhancing ingredients found in energy drinks. The number of emergency department visits involving energy drinks doubled over the past 5 years. Reviews of the health complications have highlighted adverse cardiovascular events. The literature reveals that caffeine is known to moderately increase blood pressure (BP) and heart rate (HR). The purpose of this study was to determine the effect of 3 different energy drinks on cardiovascular and performance measures. Fifteen recreational runners completed 5 trials. The first trial consisted of a graded exercise protocol. The 4 remaining trials consisted of 15-minute economy trials at a treadmill speed consistent with 70% of subject's V[Combining Dot Above]O2max. An hour before subjects ingested 1 of the 3 energy drinks or a placebo. HR, BP, V[Combining Dot Above]O2, and rating of perceived exertion (RPE) were recorded during the 15-minute trial. Mean values for dependent measures were compared using repeated-measures analysis of variance. Fifteen-minute systolic BP readings were significantly lower in the placebo trials (156.93 ± 15.50) in relation to the 3 energy drink trials (163.87 ± 13.30, 166.47 ± 13.71, and 165.00 ± 15.23). There were no significant differences in diastolic BP and HR. There were no significant differences found in V[Combining Dot Above]O2 or RPE measures. Ingestion of energy drinks demonstrated no change in V[Combining Dot Above]O2 or RPE during the economy trials. The findings show no performance benefits under the conditions of this study. However, there does appear to be a significant increase in systolic BP.

Faster self-paced rate of drinking for alcohol mixed with energy drinks versus alcohol alone.

The consumption of alcohol mixed with energy drinks (AmED) has been associated with higher rates of binge drinking and impaired driving when compared with alcohol alone. However, it remains unclear why the risks of use of AmED are heightened compared with alcohol alone even when the doses of alcohol consumed are similar. Therefore, the purpose of this laboratory study was to investigate if the rate of self-paced beverage consumption was faster for a dose of AmED versus alcohol alone using a double-blind, within-subjects, placebo-controlled study design. Participants (n = 16) of equal gender who were social drinkers attended 4 separate test sessions that involved consumption of alcohol (1.97 ml/kg vodka) and energy drinks, alone and in combination. On each test day, the dose assigned was divided into 10 cups. Participants were informed that they would have a 2-h period to consume the 10 drinks. After the self-paced drinking period, participants completed a cued go/no-go reaction time (RT) task and subjective ratings of stimulation and sedation. The results indicated that participants consumed the AmED dose significantly faster (by ∼16 min) than the alcohol dose. For the performance task, participants' mean RTs were slower in the alcohol conditions and faster in the energy-drink conditions. In conclusion, alcohol consumers should be made aware that rapid drinking might occur for AmED beverages, thus heightening alcohol-related safety risks. The fast rate of drinking may be related to the generalized speeding of responses after energy-drink consumption. (PsycINFO Database Record

Desire to Drink Alcohol is Enhanced with High Caffeine Energy Drink Mixers.

BACKGROUND: Consumption of alcohol mixed with energy drinks (AmED) has been associated with a variety of risks beyond that observed with alcohol alone. Consumers of AmED beverages are more likely to engage in heavy episodic (binge) drinking. This study was to investigate whether the consumption of high caffeine energy drink mixers with alcohol would increase the desire to drink alcohol compared to the same amount of alcohol alone using a double-blind, within-subjects, placebo-controlled study design. METHODS: Participants (n = 26) of equal gender who were social drinkers attended 6 double-blind dose administration sessions that involved consumption of alcohol and energy drinks, alone and in combination. On each test day, participants received 1 of 6 possible doses: (i) 1.21 ml/kg vodka + 3.63 ml/kg decaffeinated soft drink, (ii) 1.21 ml/kg vodka + 3.63 ml/kg energy drink, (iii) 1.21 ml/kg vodka + 6.05 ml/kg energy drink, (iv) 3.63 ml/kg decaffeinated soft drink, (v) 3.63 ml/kg energy drink, and (vi) 6.05 ml/kg energy drink. Following dose administration, participants repeatedly completed self-reported ratings on the Desire-for-Drug questionnaire and provided breath alcohol readings. RESULTS: Alcohol alone increased the subjective ratings of "desire for more alcohol" compared to placebo doses. Energy drink mixers with the alcohol increased desire for more alcohol ratings beyond that observed with alcohol alone. CONCLUSIONS: This study provides laboratory evidence that AmED beverages lead to greater desire to drink alcohol versus the same amount of alcohol consumed alone. The findings are consistent with results from animal studies indicating that caffeine increases the rewarding and reinforcing properties of alcohol.

Alcohol-Related Facebook Activity Predicts Alcohol Use Patterns in College Students.

The purpose of this study was to determine if a brief 10-item alcohol-related Facebook® activity (ARFA) questionnaire would predict alcohol use patterns in college students (N = 146). During a single laboratory session, participants first privately logged on to their Facebook® profiles while they completed the ARFA measure, which queries past 30 day postings related to alcohol use and intoxication. Participants were then asked to complete five additional questionnaires: three measures of alcohol use (the Alcohol Use Disorders Identification Test [AUDIT], the Timeline Follow-Back [TLFB], and the Personal Drinking Habits Questionnaire [PDHQ]), the Barratt Impulsiveness Scale (BIS-11), and the Marlowe-Crowne Social Desirability Scale (MC-SDS). Regression analyses revealed that total ARFA scores were significant predictors of recent drinking behaviors, as assessed by the AUDIT, TLFB, and PDHQ measures. Moreover, impulsivity (BIS-11) and social desirability (MC-SDS) did not predict recent drinking behaviors when ARFA total scores were included in the regressions. The findings suggest that social media activity measured via the ARFA scale may be useful as a research tool for identifying risky alcohol use.

Effects of artificial sweeteners on breath alcohol concentrations in male and female social drinkers.

BACKGROUND: Alcohol is often mixed with various nonalcoholic beverages. While consumption of food with alcohol will decrease peak breath alcohol concentrations (BrAC), recent evidence has suggested that mixing alcohol with diet beverages can result in higher BrAC when compared with mixing the same amount of alcohol with sweetened beverages. The purpose of this study was to examine this phenomenon using two different moderate alcohol doses. METHODS: Twenty participants (10 males) attended five sessions where they received 1 of 5 doses (0.91 ml/kg vodka+3.64 ml/kg of diet soda, 0.91 ml/kg vodka+3.64 of regular soda, 1.82 ml/kg vodka+7.28 ml/kg diet soda, 1.82 ml/kg vodka+7.28 ml/kg regular soda, and a placebo beverage). BrAC was recorded repeatedly up to 180 min after dose administration. RESULTS: Participants had significantly higher BrAC when the mixer was diet as compared to regular for both alcohol dose conditions. No gender differences were observed. CONCLUSIONS: Mixing alcohol with diet beverages can result in higher BrAC when compared to the same amount of alcohol administered with a similar sweetened beverage. Individuals who consume diet mixers with alcohol may reduce caloric intake but increase the harms associated with higher BrACs.

Early-life risperidone administration alters maternal-offspring interactions and juvenile play fighting.

Risperidone is an antipsychotic drug that is approved for use in childhood psychiatric disorders such as autism. One concern regarding the use of this drug in pediatric populations is that it may interfere with social interactions that serve to nurture brain development. This study used rats to assess the impact of risperidone administration on maternal-offspring interactions and juvenile play fighting between cage mates. Mixed-sex litters received daily subcutaneous injections of vehicle or 1.0 or 3.0mg/kg of risperidone between postnatal days (PNDs) 14-42. Rats were weaned and housed three per cage on PND 21. In observations made between PNDs 14-17, risperidone significantly suppressed several aspects of maternal-offspring interactions at 1-hour post-injection. At 23 h post-injection, pups administered risperidone had lower activity scores and made fewer non-nursing contacts with their moms. In observations of play-fighting behavior made once a week between PNDs 22-42, risperidone profoundly decreased many forms of social interaction at 1h post-injection. At 23h post-injection, rats administered risperidone made more non-social contacts with their cage mates, but engaged in less social grooming. Risperidone administration to rats at ages analogous to early childhood through adolescence in humans produces a pattern of abnormal social interactions across the day that could impact how such interactions influence brain development.

Can energy drinks increase the desire for more alcohol?

Energy drinks, the fastest growing segment in the beverage market, have become popular mixers with alcohol. The emerging research examining the use of alcohol mixed with energy drinks (AmEDs) indicates that the combination of caffeine-containing energy drinks with alcohol may be riskier than the use of alcohol alone. The public health concerns arising from AmED use are documented in different research domains. Epidemiologic studies reveal that the consumption of AmEDs is frequent among young and underage drinkers, demographic groups that are more likely to experience the harms and hazards associated with alcohol use. In addition, for all consumers, elevated rates of binge drinking and risk of alcohol dependence have been associated with AmED use when compared to alcohol alone. Results from laboratory studies help explain why AmED use is associated with excessive intake of alcohol. When an energy drink (or caffeine) is combined with alcohol, the desire (or urge) to drink more alcohol is more pronounced in both humans and animals than with the same dose of alcohol alone. The experience of drinking alcohol appears to be more rewarding when combined with energy drinks. Given that caffeine in other foods and beverages increases preference for those products, further research on AmEDs may elucidate the underlying mechanisms that contribute to alcohol dependence.

Energy drinks mixed with alcohol: what are the risks?

Energy drinks are popular beverages that typically include high levels of caffeine and other ingredients such as taurine, or caffeine-containing herbs, such as guarana. While energy drinks are often consumed alone, they are also frequently used as mixers for alcoholic beverages. This review summarizes what is known about the scope of use of alcohol mixed with energy drinks, the risks associated with such mixtures, and the objective laboratory data examining how the effects of their consumption differ from consuming alcohol alone. The weight of the evidence reveals that consuming alcohol mixed with energy drinks is riskier than consuming alcohol alone and constitutes a public health concern. Consumption of these mixed beverages is frequent, especially in young and underage drinkers, and compared with alcohol alone, their use is associated with elevated rates of binge drinking, impaired driving, risky sexual behavior, and risk of alcohol dependence. Laboratory research (human and animal) has demonstrated that consuming alcohol mixed with energy drinks leads to altered subjective states including decreased perceived intoxication, enhanced stimulation, and increased desire to drink/increased drinking compared to consuming alcohol alone. Possible underlying mechanisms explaining these observations are highlighted in this review.

Subjective State, Blood Pressure, and Behavioral Control Changes Produced by an "Energy Shot"

Background: Energy drinks and energy shots are popular consumer beverages that are advertised to increase feelings of alertness. Typically, these products include high levels of caffeine, a mild psychostimulant drug. The scientific evidence demonstrating the specific benefits of energy products to users in terms of subjective state and objective performance is surprisingly lacking. Moreover, there are rising health concerns associated with the use of these products. Therefore, the purpose of this study was to investigate the acute effects of a popular energy shot (5-Hour Energy®) on subjective and objective measures that were assessed hourly for 6 hours following consumption. Methods: Participants (n=14) completed a three-session study where they received the energy shot, a placebo control, and no drink. Following dose administration, participants completed subjective Profile of Mood States ratings hourly for 6 hours. Participants also repeatedly completed a behavioral control task (the cued go/no-go task) and provided blood pressure and pulse rate readings at each hour. Results: Consumption of the energy shot did improve subjective state, as measured by increased ratings of vigor and decreased ratings of fatigue. However, the energy shot did not alter objective performance, which worsened over time. Importantly, the energy shot elevated both systolic and diastolic blood pressure. Conclusions: Consumption of one energy shot may only result in modest benefits to subjective state. Individuals with preexisting hypertension or other medical conditions should be cautious about using these new consumer products.

Combined alcohol and energy drink use: hedonistic motives, adenosine, and alcohol dependence.

Consumption of alcohol mixed with energy drinks (AmED) has been associated with both short- and long-term risks beyond those observed with alcohol alone. AmED use has been associated with heavy episodic (binge) drinking, risky behaviors, and risk of alcohol dependence. Laboratory research has demonstrated that AmED beverages lead to greater motivation to drink versus the same amount of alcohol consumed alone. However, the reason consumers find AmED beverages particularly appealing has been unclear. A recent report by Droste and colleagues (Alcohol Clin Exp Res 2014; 38:2087-2095) is the first study to investigate motivations related to AmED consumption and to determine which motives predict AmED consumption patterns, experience of drinking-related harms, and risk of alcohol dependence. The findings of this study significantly enhance our understanding of why AmED consumption is related to the risk of alcohol dependence and change our understanding of why consumers choose AmED beverages. The authors report that hedonistic motives strongly predicted AmED use and the harms associated with use. While intoxication-reduction motives predicted self-reported accidents and injuries, these motives did not predict AmED consumption patterns and risk of dependence. The risk of alcohol dependence may arise from repeated experiences when drinking alcohol is more pleasurable when energy drinks are consumed with the alcohol. This commentary will focus on why energy drinks might increase the rewarding properties of alcohol in social drinkers. In addition, discussion is provided explaining why more research on the neurotransmitter, adenosine, may actually inform us about the mechanisms contributing to the development of alcohol dependence.

Adult rats treated with risperidone during development are hyperactive.

Risperidone is an antipsychotic drug approved for use in children, but little is known about the long-term effects of early-life risperidone treatment. In animals, prolonged risperidone administration during development increases forebrain dopamine receptor expression immediately upon the cessation of treatment. A series of experiments was performed to ascertain whether early-life risperidone administration altered locomotor activity, a behavior sensitive to dopamine receptor function, in adult rats. One additional behavior modulated by forebrain dopamine function, spatial reversal learning, was also measured during adulthood. In each study, Long-Evans rats received daily subcutaneous injections of vehicle or 1 of 2 doses of risperidone (1.0 and 3.0 mg/kg per day) from postnatal Days 14 to 42. Weight gain during development was slightly yet significantly reduced in risperidone-treated rats. In the first 2 experiments, early-life risperidone administration was associated with increased locomotor activity at 1 week postadministration through approximately 9 months of age, independent of changes in weight gain. In a separate experiment, it was found that the enhancing effect of early-life risperidone on locomotor activity occurred in males and female rats. A final experiment indicated that spatial reversal learning was unaffected in adult rats administered risperidone early in life. These results indicate that locomotor activity during adulthood is permanently modified by early-life risperidone treatment. The findings suggest that chronic antipsychotic drug use in pediatric populations (e.g., treatment for the symptoms of autism) could modify brain development and alter neural set points for specific behaviors during adulthood.