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Rats were given two weeks of home cage access to either "near-beer" (a beverage that tastes like beer but contains <0.5% ethanol v/v) or near-beer with added ethanol (4.5% v/v), which is simply referred to as "beer". The two groups of rats (near-beer and beer) were then trained on a "lick-based progressive ratio paradigm" in operant chambers in which an ever increasing number of licks had to be emitted for each successive fixed unit of near-beer or beer delivered. Break points (the ratio at which responding ceased) for near-beer and beer were approximately equal under baseline conditions. Rats were then tested for the effects of the 5HT2A/2C receptor antagonist ritanserin (0.625, 2.5 or 10 mg/kg), the opioid receptor antagonist naloxone (0.625, 2.5 or 10 mg/kg) or the cannabinoid CB1 receptor antagonist SR 141716 (0.3, 1 or 3 mg/kg). All three drugs caused a dose-dependent reduction of break-points and locomotor activity in both the beer and near-beer groups. However, the effects of SR 141716 and naloxone, but not ritanserin, on breakpoints were significantly more pronounced on rats drinking beer compared to those drinking near-beer. There were no such differential effects of any of the drugs on locomotor activity across the two groups. These results suggest that both SR 141716 and naloxone differentially affect the motivation to consume alcoholic beverages and may thus have potential as drugs for the treatment of alcohol craving.

A recent study found that false memories were reduced by 36% when low frequency repetitive transcranial magnetic stimulation (rTMS) was applied to the left anterior temporal lobe after the encoding (study) phase. Here we were interested in the consequences on a false memory task of brain stimulation throughout the encoding and retrieval task phases. We used transcranial direct current stimulation (tDCS) because it has been shown to be a useful tool to enhance cognition. Specifically, we examined whether tDCS can induce changes in a task assessing false memories. Based on our preliminary results, three conditions of stimulation were chosen: anodal left/cathodal right anterior temporal lobe (ATL) stimulation (“bilateral stimulation”); anodal left ATL stimulation (with a large contralateral cathodal electrode – referred as “unilateral stimulation”) and sham stimulation. Our results showed that false memories were reduced significantly after the two active conditions (unilateral and bilateral stimulation) as compared with sham stimulation. There were no significant changes in veridical memories. Our findings show that false memories are reduced by 73% when anodal tDCS is applied to the anterior temporal lobes throughout the encoding and retrieval stages, suggesting a possible strategy for improving certain aspects of learning.

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Objective: Inhibiting the anterior temporal lobe (ATL) via repetitive transcranial magnetic stimulation (rTMS) appears to have deleterious effects on people's semantic conceptualization, and left ATL damage is associated with semantic dementia. However, little research has investigated whether rTMS can inhibit conceptual schemata that have potentially negative consequences. Our aim was to investigate whether rTMS to the ATLs could reduce scores on a standard measure of prejudice (implicit association test, IAT). Method: Forty (17 female; mean age 20.6) neurologically normal, right-handed undergraduates participated. Participants were randomly allocated into one of four rTMS stimulation conditions-left ATL, right ATL, control site (motor cortex, Cz), and sham stimulation. All participants completed a modified IAT, where "good" and "bad" words were replaced with "terrorist" and "law-abider" words, and, "Black" and "White" were replaced with "Arab" and "Non-Arab" words. Participants were then given 15 min of rTMS stimulation. Afterward, participants completed a parallel form of the IAT. Results: To investigate the effects of rTMS on IAT scores, a one-way ANOVA on the difference between pre-and postscores was carried out revealing that there were significant between group differences (F3,36 ϭ 3.57; p ϭ .02). Planned contrasts revealed that both left and right ATL stimulation significantly reduced IAT scores poststimulation, indicating lower prejudice. Conclusion: We show that prejudice scores can be significantly reduced by inhibitory rTMS delivered to the bilateral ATLs. This may implicate this area in conceptual associations that lead to overgeneralization and stereotyping of social groups.