The genetics of alcohol reinforcement has been discussed in depth (see Cunningham and Phillips, 2003). Other tests of reinforcement (e.g., oral operant self-administration procedures), show that animals will work to obtain access to or avoid ethanol, but there are no QTL data available for these models. Another way to assess alcohol's reward value is to use classical conditioning. Conditioning can be used to associate the effects of an ethanol injection with the environment in which it was administered (place conditioning), or to associate alcohol's effects with ingestion of a novel flavor (taste conditioning). However, there are very limited QTL data available for these models. The reinforcing effect of ethanol has also been modeled in mice based upon the locomotor stimulant response, and with its tendency to sensitize, or grow more pronounced with repeated administrations of the drug. The putative link to reinforcement obtains from the participation of brain dopaminergic systems, particular corticolimbic pathways, in both reward and motor stimulation. For a discussion of genetic contributions to the stimulant effects, see Phillips (1997). There are numerous QTL reported for ethanol-stimulated activity,
