Binge Drinking and Memory in Adolescents and Young Adults

The binge drinking (BD) pattern of alcohol consumption, characterized by intermittent consumption of large quantities of alcohol in short periods, is currently prevalent during adolescence and early youth. This period is characterized by critical changes to the structural and functional development of brain areas related with memory, as well as other executive functions. As a result, BD has been associated with undermined learning and memory ability in adolescents and youths of both sexes. One distinctive contribution of this chapter is to evaluate, together, the impact of an acute BD episode, the sample’s history of consumption, and its effect on learning and memory performance and as potential gender differences. The main findings of the published research show that BD has differential effects on several types of memory and confirm that women are more vulnerable to these detrimental effects of alcohol than are men. These cognitive differences between men and women seem to be overridden as the blood alcohol concentration progressively increases. As BD pattern of consumption has been associated with inhibitory control deficits, future research also should investigate long-term implementation of inhibitory control training, emphasizing the importance of this training as part of the intervention strategies focused on this at-risk group

Physiological and Psychological Effects of a High Dose of Alcohol in Young Men and Women

The objective of this study was to evaluate the effects of a high dose of alcohol on physiological and psychological parameters in young men and women with a previous history of alcohol consumption. Systolic and diastolic blood pressure, heart rate, state anxiety, attention, time estimation and manual dexterity were registered before (phase 1) and after (phase 2) intake of alcohol (38.4 g) or a non-alcoholic beverage. Trait anxiety was registered in phase 2 only. The results showed that acute consumption of a high dose of alcohol: i) improves attention in men (although the performance of alcohol consumers was not better than that of non-consumers); ii) blocks the systolic blood pressure habituation phenomenon (observed in controls) in women; and iii) blocks the improvement in manual dexterity (associated with experience in non-consumers) in both sexes. On the other hand, male consumers had a lower heart rate than non-consumers, independently of the phase, while female consumers had a higher state anxiety and performed worse in attention than controls, also independently of the phase. These results help to understand the extent of performance impairment of different tasks produced by risk alcohol consumption in young men and women

Psicothema

Resumen tomado de la publicaciónEl antibiótico anisomicina inhibe la síntesis de proteínas, la cual muchos estudios indican que es necesaria para la formación de la memoria a largo plazo. En el presente trabajo se estudiaron los efectos de la administración aguda subcutánea de anisomicina sobre la consolidación de la memoria en una tarea de evitación inhibitoria en ratones CD1 de ambos sexos. Los animales fueron separados por sexo y distribuidos al azar en tres grupos: dos grupos fueron inyectados con 150 mg/kg de anisomicina, uno inmediatamente después de la fase de entrenamiento y el otro 24 h después, mientras que el grupo control recibió suero salino. El intervalo entre el entrenamiento y el test fue de cuatro días. La anisomicina administrada inmediatamente después del entrenamiento produjo un deterioro de memoria estadísticamente significativo, deterioro que no fue observado cuando el fármaco fue administrado 24 h después del entrenamiento. No se observaron diferencias de sexo en los efectos de la anisomicina. Estos resultados extienden a las hembras los efectos deteriorantes de la anisomicina sobre la memoria previamente observados en machos y respaldan la hipótesis de que el establecimiento de la memoria a largo plazo depende de la síntesis de proteínas poco después del entrenamiento.AsturiasColegio Oficial de Psicólogos de Asturias; Calle Ildefonso Sánchez del Rio, 4-1õB; 33001 Oviedo; Tel. +34985285778; Fax +34985281374;ES

Hippocampus and two way active avoidance conditioning: contrasting effects of cytotoxic lesion and temporary inactivation

Hippocampal lesions tend to facilitate two way active avoidance (2WAA) conditioning, where rats learn to cross to the opposite side of a conditioning chamber to avoid a tone-signaled footshock. This classical finding has been suggested to reflect that hippocampus-dependent place/context memory inhibits 2WAA (a crossing response to the opposite side is inhibited by the memory that this is the place where a shock was received on the previous trial). However, more recent research suggests other aspects of hippocampal function that may support 2WAA learning. More specifically, the ventral hippocampus has been shown to contribute to behavioral responses to aversive stimuli and to positively modulate the meso-accumbens dopamine system, whose activation has been implicated in 2WAA learning. Permanent hippocampal lesions may not reveal these contributions because, following complete and permanent loss of hippocampal output, other brain regions may mediate these processes or because deficits could be masked by lesion-induced extra-hippocampal changes, including an upregulation of accumbal dopamine transmission. Here, we re-examined the hippocampal role in 2WAA learning in Wistar rats, using permanent NMDA-induced neurotoxic lesions and temporary functional inhibition by muscimol or tetrodotoxin (TTX) infusion. Complete hippocampal lesions tended to facilitate 2WAA learning, whereas ventral or dorsal hippocampal lesions had no effect. In contrast, ventral or dorsal hippocampal muscimol or TTX infusions impaired 2WAA learning. Ventral infusions caused an immediate impairment, whereas after dorsal infusions rats showed intact 2WAA learning for 40-50 min, before a marked deficit emerged. These data show that functional inhibition of ventral hippocampus disrupts 2WAA learning, while the delayed impairment following dorsal infusions may reflect the time required for drug diffusion to ventral hippocampus. Overall, using temporary functional inhibition, our study shows that the ventral hippocampus contributes to 2WAA learning. Permanent lesions may not reveal these contributions due to functional compensation and extra-hippocampal lesion effects

Blood Alcohol Concentration-Related Lower Performance in Immediate Visual Memory and Working Memory in Adolescent Binge Drinkers

The binge drinking (BD) pattern of alcohol consumption is prevalent during adolescence, a period characterized by critical changes to the structural and functional development of brain areas related with memory and cognition. There is considerable evidence of the cognitive dysfunctions caused by the neurotoxic effects of BD in the not-yet-adult brain. Thus, the aim of the present study was to evaluate the effects of different blood alcohol concentrations (BAC) on memory during late adolescence (18–19 years old) in males and females with a history of BD. The sample consisted of 154 adolescents (67 males and 87 females) that were classified as refrainers if they had never previously drunk alcoholic drinks and as binge drinkers if they had drunk six or more standard drink units in a row for men or five or more for women at a minimum frequency of three occasions in a month, throughout the previous 12 months. After intake of a high acute dose of alcohol by binge drinkers or a control refreshment by refrainers and binge drinkers, subjects were distributed into four groups for each gender according to their BAC: BAC0-R (0 g/L, in refrainers), BAC0-BD (0 g/L, in binge drinkers), BAC1 (0.3 – 0.5 g/L, in binge drinkers) or BAC2 (0.54 – 1.1 g/L, in binge drinkers). The subjects’ immediate visual memory and working memory were then measured according to the Wechsler Memory Scale (WMS-III). The BAC1 group showed lower scores of immediate visual memory but not of working memory, while lower performance in both memories were found in the BAC2 group. Therefore, the brain of binge drinkers with moderate BAC could be employing compensatory mechanisms from additional brain areas to perform a working memory task adequately, but these resources would be undermined when BAC is higher (>0.5 g/L). No gender differences were found in BAC-related lower performance in immediate visual memory and working memory. In conclusion, immediate visual memory is more sensitive than working memory to the neurotoxic effects of alcohol in adolescent binge drinkers of both genders, being a BAC-related lower performance, and without obvious differences between males and females

Indomethacin counteracts the effects of chronic social defeat stress on emotional but not recognition memory in mice

<div><p>We have previously observed the impairing effects of chronic social defeat stress (CSDS) on emotional memory in mice. Given the relation between stress and inflammatory processes, we sought to study the effectiveness of the anti-inflammatory indomethacin in reversing the detrimental effects of CSDS on emotional memory in mice. The effects of CSDS and indomethacin on recognition memory were also evaluated. Male CD1 mice were randomly divided into four groups: non-stressed + saline (NS+SAL); non-stressed + indomethacin (NS+IND); stressed + saline (S+SAL); and stressed + indomethacin (S+IND). Stressed animals were exposed to a daily 10 min agonistic confrontation (CSDS) for 20 days. All subjects were treated daily with saline or indomethacin (10 mg/kg, i.p.). 24 h after the CSDS period, all the mice were evaluated in a social interaction test to distinguish between those that were resilient or susceptible to social stress. All subjects (n = 10–12 per group) were then evaluated in inhibitory avoidance (IA), novel object recognition (NOR), elevated plus maze and hot plate tests. As in control animals (NS+SAL group), IA learning was observed in the resilient groups, as well as in the susceptible mice treated with indomethacin (S+IND group). Recognition memory was observed in the non-stressed and the resilient mice, but not in the susceptible animals. Also, stressed mice exhibited higher anxiety levels. No significant differences were observed in locomotor activity or analgesia. In conclusion, CSDS induces anxiety in post-pubertal mice and impairs emotional and recognition memory in the susceptible subjects. The effects of CSDS on emotional memory, but not on recognition memory and anxiety, are reversed by indomethacin. Moreover, memory impairment is not secondary to the effects of CSDS on locomotor activity, emotionality or pain sensitivity.</p></div

Schedule of CSDS procedure and behavioral tasks performed.

<p>SI: social interaction; EPM: elevated plus maze; IA (Tr.): inhibitory avoidance training; IA (Test): inhibitory avoidance test; NOR: novel object recognition; HP: hot plate.</p