|
Continuous free choice
|
Easy to implement Simple method for assessing pro-pensity to voluntarily drink Provides measures of general preference for and consumption of alcohol Extensively used for investigating genetic determinants of alcohol prefer-ence and consumption
|
Difficult to determine whether alcohol consumption results in intoxication (significant elevation in blood alcohol levels) Temporal pattern of alcohol intake is typically not ascertained Limited utility for studies probing mechanisms underlying motivational aspects of drinking
|
|
Scheduled limited access
|
Mimics “binge-like” pattern of intake when access is appropriately scheduled Engenders high levels of alcohol consumption Affords opportunity to more accurately correlate intake with resultant blood alcohol levels Enables examination of relation-ship between alcohol intake and mea-sures of intoxication
|
High levels of drinking during limited access conditions may not predict high drinking when access is not restricted Limited utility for studies probing mechanisms underlying motivational aspects of drinking
|
|
Scheduled deprivation
|
Models alcohol relapse and crav-ing Can be studied using home-cage drinking and operant self-administration procedures Translational value as repeated cycles of deprivation lead to more robust and durable effect
|
Lack of specificity: Exagger-ated intake following deprivation observed for other rewards (e.g., sucrose) High propensity for alcohol preference/intake may not predict robust expression of alcohol depri-vation effect Increased intake following deprivation periods may be transient
|
|
Intermittent access
|
|
Genetic models of high alco-hol preference/intake may limit escalation effect Observation of escalated alco-hol intake highly dependent on vari-ous biological and experimental factors (e.g., age, sex, housing conditions)
|
|
Schedule-induced polydipsia
|
|
Lack of specificity: same pro-cedure leads to excessive intake of any fluid (including water) Requires food deprivation, clouding interpretation of motivation Once schedule is relaxed, alcohol intake reverts to control levels (in rodent models)
|
|
Alcohol dependence and withdrawal
|
Leads to escalation of voluntary intake that results in significant elevated blood and brain alcohol levels Can be employed to study both physical signs of withdrawal and moti-vational factors that influence alcohol consumption Escalation of alcohol intake observed in home-cage drinking and operant self-administration procedures Increased intake is specific to alcohol (consumption of other palatable substances not altered)
|
Requires unique setup for delivery of alcohol vapor Induction of alcohol depen-dence involves experimenter-administered alcohol Some unique methodological issues need to be considered in studies involving rats vs. mice
|
