The MazeEngineers Shuttle Box is a versatile tool designed for conducting both active and passive avoidance tests. It features dual independent grid floors that can be customized with various adverse stimuli. The top-loading door facilitates convenient access to the interior of the box. Inside, the cage is equipped with a sound generator and a visual stimulus (light), each controllable separately for different compartments.
Rodents are monitored using two distinct sensor arrays known for their high sensitivity and accuracy. The collected data can be analyzed using Noldus Ethovision software and seamlessly integrated with Neuralynx through Conductor Software.
Please note: An Isolation Chamber is not included with this system.
$6,900.00 – $7,900.00
Mouse Shuttle Box Features |
2 Dual control speakers |
2 Dual control lights |
2 Dual control shock grids |
Top lid |
Acrylic plating: allow for adjustable contexts; black/black plating for active avoidance; and white/black plating for passive avoidance. (Remove plates for clear context) |
Note: Sound Attenuation Chamber sold separately |
Rat Shuttle Box Features |
2 Dual control speakers |
2 Dual control lights |
2 Dual control shock grids |
Top lid |
Acrylic plating: allow for adjustable contexts; black/black plating for active avoidance; and white/black plating for passive avoidance. (Remove plates for clear context) |
Note: Sound Attenuation Chamber sold separately |
Take advantage of Neuralynx, Ethovision Integration, SMS and Email integration with the Conductor Science Software. No I/O Boxes Required
Passive avoidance experiments involve training animals to avoid an unpleasant event by inhibiting a specific behavior. For effective learning, the aversive stimulus must be clearly linked to the behavioral action that needs to be suppressed.
Typically, the passive avoidance test is conducted using a shuttle box that features a light chamber and a dark chamber divided by a doorway (known as the step-through method). Rodents generally prefer dark environments due to their natural aversion to light. Initially, they are allowed to move freely between the chambers during the habituation phase. However, during the conditioning phase, the animal receives a foot shock when it enters the dark chamber. As a result, the rodent’s natural inclination to seek darkness becomes associated with the unpleasant stimulus. Consequently, when placed back in the light chamber, the rodent will avoid entering the dark chamber to prevent the aversive experience (Bures et al., 1976).
Active avoidance involves performing a specific behavior to escape or prevent an aversive stimulus. This conditioning approach requires the animal to learn how to influence the occurrence of an unconditioned stimulus (US), such as a foot shock, by responding to a conditioned stimulus (CS) like a light cue that precedes the US. Initially, the animal learns to escape from the US. With repeated training, it begins to anticipate the aversive event and can avoid it entirely. In an active avoidance test, a rodent is placed in a shuttle box and trained to move to the opposite side of the box when it receives a cue signaling an impending foot shock. Moving to the other side of the chamber in response to the shock-predictive cue is classified as active avoidance, while moving only after the foot shock has been delivered is considered an escape response (Bures et al., 1976).
Memory of learned avoidance can be evaluated at various intervals post-conditioning, typically shown by an increased latency to enter the dark chamber. This increased latency indicates the animal’s capacity for learning.
Disruptions to the ability to avoid unpleasant stimuli can be caused by brain injuries, among other factors. Traditionally, passive avoidance tasks have been employed to assess learning deficits resulting from drug administration, brain lesions, and other behavioral manipulations (e.g., Martini et al., 2008; SaÅat et al., 2017).
The purpose of the passive and active avoidance tests is to evaluate learning in rodentsĀ in a control vs. disease model/intervention group, by assessing their fear-based conditioned avoidance behavior.
There are several versions of protocols to be used with the passive and active avoidance tests, varying in the apparatus used for the test, for example. Here, we describe a general protocol to be used with a shuttle box apparatus.
The apparatus should be placed in a soundproof or quiet room to minimize external noise during the tests; animals should also be housed in a different room. This prevents the animals that are not being subjected to a test from hearing any vocalizations from the animals being tested. Soundproof chambers can also be purchased from MazeEngineers.
Animals should be calm before the test, since too much fear or stress interferes with avoidance acquisition. Therefore, it is recommended that the animals have a long habituation period, so that they become familiarized with the room in which the test is carried out and with the apparatus.
The shock must have an intensity that prevents freezing or disoriented running and jumping, but that is sufficient to adequately motivate the animal to avoid it.Ā (between 0.05-1.5 mA, but the adequate intensity should be established in preliminary trials).
Passive avoidance test
In the passive avoidance test, one of the chambers of the shutter box is illuminated and the other is dark.
The mouse or rat is carefully placed into the illuminated chamber facing away from the dark chamber (start position); this should always be done in a standard way.
The animal will quickly turn around, find the entrance to the preferred dark chamber, and enter it. After 10 sec in the dark chamber, the animal must be taken from the dark chamber into the home cage. The procedure is repeated three times at 30 min intervals. Ā
A single trial is performed. The animal is carefully placed in the start position.
As soon as the dark chamber of the shutter box is reached with all four paws, a foot shock is applied for 1 sec.
The animal is then immediately returned to its home cage.
The time from releasing the animal in the starting position to its stepping into the dark compartment (step-through latency) is measured.
Learning can be tested at different times after acquisition by presenting the animal to the same paradigm.
The animal is placed in the starting position in the light chamber and the step-through latency is measured again. The step-through latency is counted from the moment of the animalās release. The test is concluded when the animal enters the dark compartment or when it fails to do so in less than 3 min.
During retention testing, most animals remain motionless in the light chamber. Only some explore the entrance to the dark compartment. Almost all animals reach the 3 min cut-off limit.
Active avoidance test
In the active avoidance test, chambers of the shutter box are similarly illuminated. Multiple conditioning trials are required for the animal to acquire active avoidance behavior. It usually takes 10ā20 trials before the first avoidance reaction appears.
The animal is allowed to explore the apparatus for 5 min with the connecting door open and the compartment lights switched off.
The guillotine door is closed. After 20 sec the light is switched on in the compartment containing the animal, and the door is raised (CS).
Five seconds later, the foot shock (US) is applied and left on until the animal escapes to the dark side of the box.
Immediately after the rat enters the dark compartment, the connecting door is closed and both the US and CS are discontinued.
After a variable inter-trial interval (30ā90 sec), the light is switched on in the previously dark compartment, the door is raised and the animal is required to cross to the other side to avoid the foot shock.
The training is continued until the animal reaches a criterion run of 9 avoidances in 10 consecutive trials (for example).
For each trial, the escape or avoidance latency is measured.
Retention can be tested at different times after acquisition by presenting the animal to the same paradigm.
The escape or avoidance latency is measured in consecutive trials separated by a variable inter-trial (30ā90 sec) interval, until the criterion run is reached (similar to the learning phase). In this case, results may be presented as escape/avoidance latencies throughout trials.
Alternatively, the same number of trials (in blocks of ten) can be performed in acquisition and learning. In this case, results may be presented as the number of avoidances in 10-block trials.
Avoidance behavior can also emerge without any external conditioned stimulus (CS) if unconditioned stimuli are administered at consistent intervals (Sidman avoidance; Sidman, 1953). In this setup, the passage of time or time-related signals act as the CS. The door between the chambers remains open, and both chambers are kept dark. Every time the animal moves from one side to the other, the fixed inter-trial interval (for instance, 60 seconds) is reset. The unconditioned stimulus (US) is delivered only if the animal does not respond within this interval.
In more advanced paradigms, the animal may be required to perform a specific action, such as pressing a lever, standing, vocalizing, or covering a certain distance, to avoid the onset of the US and turn off the CS.
The data obtained from the passive and active avoidance tests is generally visualized by graphing the latency to avoid the aversive stimulus.
For the passive avoidance test, results can be presented by graphing the average avoidance latency for each experimental group.
For the active avoidance test, results can be presented in different ways depending on the chosen protocol. If the escape or avoidance latency is measured in consecutive trials until the criterion run is reached (e.g. 9 avoidances in 10 consecutive trials), results may be graphed as escape/avoidance latencies throughout trials (the time between the CS and the US defines the cutoff time between avoidance and escape behavior).
If the same number of trials is performed in acquisition and in the retention test, results can be graphed as the number of avoidances in 10-block trials.
Using graphs similar to these allows to compare the avoidance behavior between different disease or treatment groups and their effect on learning.
A key limitation of passive and active avoidance tests is their sensitivity to environmental stress and handling. This issue can be mitigated by reducing stressors as much as possible. For instance, minimize disruptions when transferring animals to and from the testing environment. The apparatus should be situated in a quiet or soundproof room to limit external noise during testing. Additionally, animals should be housed separately to avoid exposure to any vocalizations from the test subjects. Consistency in sensory stimuli is crucial, so variations should be avoided, and testing should be conducted at the same times each day.
Bures J, et al (1976). Techniques and Basic Experiments for the Study of Brain and Behavior.Ā Chapter 3 ā Learning and memory. Pages 91ā169.
Herrnstein, R.J. (1969).Ā Method and theory in the study of avoidance. Psychol. Rev., 76, 49-69.
Martini E, et al (2008).Ā Design, synthesis and preliminary pharmacological evaluation of new analogues of DM232 (unifiram) and DM235 (sunifiram) as cognition modulators. Bioorg Med Chem, 16(23):10034-42.
SaÅat K, et al (2017).Ā Novel, highly potent and in vivo active inhibitor of GABA transporter subtype 1 with anticonvulsant, anxiolytic, antidepressant and antinociceptive properties. Neuropharmacology, 113(Pt A):331-342.
Sidman, M. (1953)Ā Avoidance conditioning with brief shock and no exteroceptive warning signal.Ā Science, 118, 157ā158.
| Species | Mouse, Rat |
|---|
There are no questions yet. Be the first to ask a question about this product.
Monday – Friday
9 AM – 5 PM EST
DISCLAIMER: ConductScience and affiliate products are NOT designed for human consumption, testing, or clinical utilization. They are designed for pre-clinical utilization only. Customers purchasing apparatus for the purposes of scientific research or veterinary care affirm adherence to applicable regulatory bodies for the country in which their research or care is conducted.
