Drug Self-Administration and Reinstatement Tests
The drug self-administration test has perhaps the highest predictive validity, defined as the ability of a rodent behavioral test to predict the effect of a drug in humans. Sessions are performed in operant boxes with grid floors, houselight, two nose-poke ports with lights, and a tone generator. A pre-determined number of nose pokes into the active port will deliver reward, elicit the tone and active nose poke light to turn on, and initiate a time out. In experiments where specific brain regions will be manipulated, the control manipulation involves tethering the animal to a fiber optic commutator.
Conditioned Place Preference / Aversion
This test is used to measure the rewarding or aversive motivational effects of objects or experiences (e.g., abused drugs). It provides measurement of a trait in the same general domain as self-administration. This protocol involves three phases: 1) habituation (pretest), 2) conditioning of an association between the drug and a tactile or visual stimulus, and 3) a test that offers a choice between the drug-associated cue and a neutral cue. If the conditioning has motivational significance, animals spend significantly more time (preference) or less time (aversion) in proximity to the cue.
Real-Time Place Preference / Avoidance
In this test, the animal is placed in a rectangular open field with two distinct halves. One of these sides is usually paired with optogenetic stimulation (e.g. astrocyte depolarization). Depending on whether this stimulation is activating or deactivating, this can be a rewarding or aversive stimulus for the animal. If the rodent spends more time on the half of the open field where stimulation is activated, then the activation is considered rewarding. If the animal avoids this side, the stimulus is considered aversive.
This test is used to assess anxiety. The basic measure is the animal's preference for enclosed over exposed places. The animal is placed on the apparatus and observed for a set time. The innate conflict is between the tendency of mice and rats to explore a novel environment versus their preference to avoid the brightly lit open raised sections by staying in the dark enclosed sections. The elevated maze test also has high predictive validity as benzodiazepines, which are widely used to treat anxiety in patients, reduce the extent to which rodents display anxiety-like behavior.
Open Field Exploratory Locomotion
Several tests rely on spontaneous rodent behavior, such as the exploration of a novel environment in the open field. The open field is a simple apparatus that can be used to measure locomotor activity (horizontal and vertical), hyperactivity, exploratory activity, rearing, and stereotyped rotation. Automated and video equipment provides measures of total distance, horizontal and vertical activity, and center time.
The rotarod test is a motor function test. The mouse is placed on a slowly rotating, grooved rubber rod. The rod accelerates from 4 revolutions per minute to 40 revolutions per minute during a test session. Latency to fall is a measure of motor coordination and balance.
User Support Services
Our core provides the following services:
- Consultation to affiliate investigators using mouse models which includes information about relevant behavioral tests and experimental designs, as well as assistance with the IACUC review process, and data extraction and interpretation.
- Training in appropriate behavioral testing protocols and coordination of animal housing and behavioral testing in the facilities.
- Coordinated services across the Genetics, Imaging, Optoexcitability, and Data Analysis Cores to facilitate interdisciplinary research approaches.
- Behavioral validation of novel genetic constructs, to include determination of baseline activity in all behavioral tests needed.
- Identification of issues and development of best practices for future behavioral testing.
- Surgery services (stereotaxic injections, cannula placements, etc.).