ABSTRACT
Alcohol consumption in adolescents causes negative effects on familiar, social, academic life, as well as neurocognitive alterations. The binge drinking (BD) pattern of alcohol is characterized by the alternation of episodes of heavy drinking in a short interval of time, and periods of abstinence, a practice that can result in important brain alterations; even more than regular alcohol consumption. The prefrontal cortex, which acts as neural support for the executive processes, is particularly affected by alcohol; however, not all studies are in agreement about how BD alcohol consumption affects executive functioning. Some research has found that alcohol consumption in adolescence does not significantly affect executive functioning while others found it does. It is possible that these discrepancies could be due to the history of alcohol consumption, that is, at what age the subjects started drinking. The aim of our study is to assess the performance on executive functioning tasks of 13-19-year-old adolescents according to their pattern of alcohol consumption. We hypothesize that BD adolescents will perform worse than non-BD subjects in tasks that evaluate executive functions, and these differences will increase depending on how long they have been consuming alcohol. Three hundred and twenty-two students (48.14% females; age range 13-22 years; mean aged 16.7 ± 2.59) participated in the study; all of them had begun drinking at the age of 13 years. Participant were divided into three groups, according to their age range (13-15, 16-18, and 19-22 years) and divided according to their pattern of alcohol consumption (BD and control groups). Then, the subjects were evaluated with neuropsychological tasks that assess executive functions like working memory, inhibition, cognitive flexibility, or self-control among others. The entire sample showed a normal improvement in their executive performance, but this improvement was more stable and robust in the control group. Regarding the executive performance among age groups, control subjects only obtained better results than BDs in the 19-22-year-old range, whereas the performance was quite similar at younger ages. Considering that all the BD subjects started drinking at the same age (13 years old), it is possible that a kind of compensation mechanism exists in the adolescent brain which allows them to reach a normal performance in executive tasks. This theoretical mechanism would depend upon neuronal labor, which could lose efficacy over time with further alcohol ingestion. This process would account for the differences in neuropsychological performance, which were only observed in older students with a longer history of alcohol consumption.
ABSTRACT
Alcohol is probably the most common legal drug of abuse in Western countries. The prevalence of binge drinking (BD) pattern of alcohol consumption among adolescents is a worrisome phenomenon. Adolescents and university students who practice a BD pattern have difficulty performing tasks involving prefrontal cortex functions, such as working memory, planning, attention, and decision making. The aim of the present study was to investigate the association between BD and executive functioning in adolescents. Two hundred twenty-three high-school students between 12 and 18 years old (15.19 ± 2.13) participated in our study. They were assigned to one of three groups according to their pattern of alcohol consumption: BD (subjects who consumed alcohol intensively, n = 48), MAC (subjects who consumed alcohol moderately, n = 53), and CTR (non-drinking subjects, n = 122). The students were evaluated with two groups of testing tools: a set of performance neuropsychological tests and two questionnaires of executive functioning. The results showed that the students who drank alcohol exhibited a more pronounced dysexecutive symptomatology (disinhibition, executive dysfunction, intentionality, executive memory), but they obtained better results than controls on some of the neuropsychological tests such as Spatial Location, Five Digit Tests, or Stroop Test. According to the results, we can deduce that heavy alcohol drinking in adolescents brings a certain dysfunction of prefrontal circuits. This prefrontal dysfunction is not so clearly demonstrated in the neuropsychological tests used, but it was observed in the performance of daily activities. In the Discussion section we raise issues about sociodemographic features of the sample and ecological validity of the traditional neuropsychological tests. The neurotoxic effects of BD on prefrontal cortex can be less evident throughout adolescence, but if alcohol consumption persists, the executive dysfunction would be exacerbated.
