Effects of valence and arousal on implicit approach/ avoidance tendencies: A fMRI study.

To date, it is still a matter of debate, whether valence or valence and arousal interactively foster implicit approach and avoidance tendencies, and which neural circuitries underlie these effects. To address these questions, we investigated the effects of valence and arousal on implicit approach/avoidance tendencies during fMRI in healthy volunteers (N=46). The implicit approach of positive social scenes was associated with shorter response preparation times and increased activation of the lingual, parahippocampal and fusiform gyri.

Selective breeding for ethanol-related traits alters circadian phenotype.

Previous studies in mice and rats have shown that selective breeding for high and low ethanol preference results in divergence of circadian phenotype in the selected lines. These results indicate that some alleles influencing ethanol preference also contribute to circadian rhythm regulation. Selective breeding has also been used to produce lines of mice differing in a number of other ethanol-related traits, while studies of phenotypic and genetic correlation indicate that diverse ethanol-related traits are influenced by both shared and unshared genetics.

Escalation of intake under intermittent ethanol access in diverse mouse genotypes.

Experimental animals offered continuous 24-hour free choice access to ethanol rarely display voluntary ethanol consumption at levels sufficient to induce intoxication or to engender dependence. One of the simplest ways to increase voluntary ethanol intake is to impose temporal limitations on ethanol availability. Escalation of ethanol intake has been observed in both rats and mice under a variety of different schedules of alternating ethanol access and deprivation.