Patent Application
20090205581
1. Field of the Invention
The present disclosure relates to apparatus and methods for use in animal sensory discrimination.
2. Background of the Invention
Current designs of operant chambers used in animal sensory tests are often based on fluid delivery systems that utilize a limited number of reservoirs connected through tubing to a manifold that is in turn connected to a spout. Sample flow is often controlled by gravity. Clogging of the tubing often complicates sample delivery. Although this type of apparatus does provide some insight into what the animal senses, such designs are generally limited by (i) the number of solutions that can be sampled by an animal, (ii) the rate at which they can be tested, and (iii) the interpretation of data. In such systems, data is often confounded by the innate thirst response of the animal, where drinking is a result of the animal being thirsty, not necessarily as a result of sensory preference.
An improved alternative approach to taste measurement uses an apparatus usually referred to as a “lickometer”. However, this apparatus only provides a general indication of whether a solution is avoided or preferred, and does not provide a direct quantitative indication of either innate or trained taste preferences.
What is needed is a high throughput sensory discrimination apparatus capable of measuring innate and/or trained sensory perception (e.g. taste) in a quantifiable manner.
This disclosure provides apparatus and methods for use in animal sensory discrimination. A high-throughput, multiple sample apparatus is provided that allows for rapid sampling of any number of test samples by a subject, all within a self-contained, low contamination environment. Exemplary embodiments allow for sampling of a plurality of separate sensory samples that require minimal amounts of sample and allow for a direct, quantitative measure of the desirability of a sample.
Further embodiments, features, and advantages, as well as the structure and operation of the various embodiments are described in detail below with reference to accompanying drawings.
The disclosure is described with reference to the accompanying drawings. In the drawings, like reference numbers indicate identical or functionally similar elements.
a shows a cross-section of the sensory discrimination apparatus of
b shows a cross-section of the sensory discrimination apparatus of
It should be appreciated that the particular implementations shown and described herein are examples and are not intended to otherwise limit the scope of the disclosure in any way.
An apparatus for use in animal sensory discrimination is provided, comprising: a support platform, means for supporting one or more samples, means for signaling an animal to sample the contents of the one or more samples, and means for determining when an animal samples the one or more samples.
As used herein, the term animal refers to animals of any species, including, but not limited to, mice, rats, rabbits, hamsters, guinea pigs and non-human primates (e.g., baboons, monkeys, and chimpanzees).
As shown in
As shown in
Apparatus 100 also comprises means for obtaining the animal's response to the sampled one or more samples. Exemplary means for obtaining the animals' response include one or more levers 112 and/or one or more nose poke wells 114, as part of operant panel 108. Means for obtaining the animal's response to the sampled one or more samples can be used in various combinations. For example, a lever can be used for obtaining a response to one type of sample and a nose poke well can be used for obtaining a response to another type of sample. While
Animals can be trained to sample and recognize any number of different kinds of sensory stimuli, and then respond accordingly. For example, one lever (the left lever 112 for example) is contacted when the animal samples a sample that it has been trained to recognize. In such a scenario, an additional lever (the right lever 112 for example) is contacted when the animal samples a sample that it has not been trained to recognize. For example, if the animal has been trained to recognize bitter-tasting samples, and it samples something that it determines is not bitter (e.g., sweet, spicy, salty, or control—i.e. no real discernable flavor), it would contact the right lever. However, upon sampling something bitter, it would contact the left lever indicating that the sample has a taste similar or identical to what it has been trained to recognize. Such a scenario can be carried out using the nose poke wells 114, or nose poke wells in combination with levers 112, in a similar manner. The animal can also be trained to recognize several different types of samples, and thus three or more levers (or nose poke wells) can be used during such an analysis (e.g. one lever for sweet, one lever for salty, one lever for not-trained to recognize).
As shown in
Apparatus 100, as shown in
For example, sample support means can be accessible to the animal at all times (e.g., positioned on the support platform with the animal), but the individual samples (e.g., wells 106) on the sample support means (e.g., support plate 104) can either be collectively or individually concealed from the animal. In such embodiments, each individual sample can be concealed from the animal, for example by placing a door or panel over each separate sample, or all of the samples can be collectively concealed from the animal, for example by using a door, panel or curtain to conceal the sample. When the partition is removed, the animal is then able to sample the individual sample, or collectively all of the samples, or any combination thereof.
In exemplary apparatus 100 shown in
In addition to one or more apertures 126, support platform 102 can also comprise means for concealing the sample support means, such as one or more partitions 128 covering one or more apertures 126. For example, if the sample support means (e.g., sample plate 104) is oriented below support platform 102, such that sample plate 104 can be accessed by an animal on support platform 102 through one or more apertures 126, one or more partitions 128 can be used to conceal sample plate 104 from the animal by covering over apertures 126 until such time that the operator wishes to reveal the sample(s) to the animal. As discussed throughout, partition 128 can comprise a sliding door or panel or other suitable concealing device that can then be moved to reveal a well 106 on sample plate 104 below the support platform 102.
As shown in
In step 202, an animal is signaled that a test sample is available for sampling. In step 204, the animal's response to the test sample is received. The animal can be signaled that a sample is available for sampling using any suitable means described herein or known in the art. For example, a signal light, bell, whistle, alarm or other signaling means can be used to signal the animal that a test sample on the sample support means is available for sampling.
After the animal has sampled the contents of the sample, the animal's response to the sample is received through the use of means for obtaining the animal's response. (The terms “received” and “obtained” are used interchangeably herein as they pertain to the animal's response). For example, the animal may contact a lever, or trigger a nose-poke well, to indicate that it has sampled the contents of the sample and determined that it is something it has been trained to recognize, or, alternatively, that it is not something it has been trained to recognize.
Following obtaining the animal's response to the first sample, at step 206, the animal is signaled that a second test sample is available for sampling. In step 208, the animal's response to the second test sample is then received. As shown in step 210, steps 206 and 208 can be repeated until all of the samples have been sampled by the animal (i.e. the animal is signaled that a third, fourth, etc., sample are available for sampling and then the animal's response to each additional sample is received).
In step 302, an animal is signaled that a test sample is available for sampling. The animal can be signaled that a sample is available for sampling using any suitable means disclosed herein or known in the art. In step 304, a test sample is revealed to the animal. Any means suitable for concealing a test sample, and then revealing the test sample to the animal, can be used. For example, a movable door, panel or other partition can be used to conceal the sample from the animal, and then moved to reveal the sample to the animal. Additional means for revealing the sample to the animal include those described herein or known in the art. The steps of signaling the animal that a sample is available for sampling 302 and revealing the sample to the animal 304 can be performed in any order. In step 306, the animal's response to the test sample is received. Suitable means for receiving/obtaining the animal's response to the test sample include those described herein as well as additional means known to those skilled in the art.
At step 308, the animal is signaled that a second test sample is available for sampling. In step 310, this second test sample is revealed to the animal, and in step 312, the animal's response to the second sample is received/obtained. Suitable means for performing these various steps include those described herein as well as additional means known to those skilled in the art. In step 314, steps 308 through 312 can then be repeated until all of the samples have been sampled by the animal (i.e. the animal is signaled that a third, fourth, etc., sample are available for sampling, the additional sample(s) are revealed to the animal, and then the animal's response to each additional sample is received).
In step 402, an animal is signaled that a first test sample in a sample well is available for sampling through an aperture in the sample platform. For example, as shown in
In step 406, the sample plate and the support platform are moved relative to each other to reveal a second test sample in a second sample well through the aperture in the sample platform. For example, as shown in
In step 410, the animal's response to the second test sample is received/obtained (e.g., by the animal contacting one or more levers, 112, or activating one or more nose-poke wells, 114). In step 412, steps 406 through 410 are then repeated until all of the samples have been sampled by the animal (i.e. the sample plate 104 and the support platform 102 are moved relative to each other to reveal a third, fourth, etc., sample; the animal is signaled that third, fourth, etc., samples are available for sampling; and the animal's response to each additional sample is received).
In step 414, the animal is rewarded for completing the sampling task(s). In additional embodiments, flowchart 400 can optionally comprise rewarding the animal in step 416 after it has provided a response to the first sample in step 404. Suitable means for rewarding the animal include those described herein, as well as additional means known to the skilled artisan. For example, the animal can be rewarded by being allowed to eat from food hopper 130.
In step 502, (with reference to
In step 508, the movable partition 128 is then moved so as to conceal the aperture 126 in support platform 102. In step 510, sample plate 104 and support platform 102 are moved relative to each other, thereby positioning a second test sample in a second sample well 106 below aperture 126 in support platform 102, for example by using motion table 118.
In step 512, movable partition 128 is moved to reveal the second test sample in the second sample well 106. In step 514, the animal is signaled that the second test sample in the sample well is available for sampling. It should be understood that steps 512 and 514 of respectively moving the movable partition to reveal the second test sample, and signaling the animal that the second test sample is available for sampling, can occur in any order. In step 516, the animal's response to the first test sample is then received/obtained. For example, the animal's response can be received by the animal contacting one or more levers 112 or activating one or more nose-poke wells 114. In step 518, steps 508 through 516 are repeated until all test samples have been sampled by the animal. After all test samples have been sampled by the animal (i.e., constituting a completed analysis session), the animal is rewarded in step 520, for example, by allowing the animal to eat from food hopper 130. In additional embodiments, flowchart 500 can optionally comprise rewarding the animal in step 522 after it has provided a response to the first sample in step 506. In still further embodiments, the animal can be rewarded following the completion of each and every sample, or a select number of samples, as desired, during the analysis session.
Flowchart 600 in
In step 602, a house light (e.g., general light in the animal's housing, not shown in
In a second possible scenario, as shown in step 608, the animal actually responds to the first sample. That is, the animal samples the sample and then “records” its response to the sample by, for example, contacting one or more levers 112 or activating one or more nose-poke wells 114, or other means for obtaining the animal's response, such as those described herein. Once the animal's response to the first sample has been obtained, the first signal light 110, A, is turned off, movable partition 128 is moved so as to close aperture 126 and support platform 102 and sample support means (e.g., sample plate 104) are moved relative to each other such that a second test sample (for example in a second sample well 106) is positioned beneath aperture 126. A second signal light 110, B, is also turned on at this time. This second signal light indicates to the animal that analysis of the first sample has been successfully completed.
In most analysis sessions, a specified criterion number of samples/responses will be required prior to rewarding the animal, or stopping the analysis session. In step 612, if it is determined that the response criteria have not been reached (i.e. not enough samples sampled/recorded by the animal, for example, only the first sample out of 5 required), the house and stimulus lights are turned off, and the analysis session is re-set back to step 602 to allow the animal to sample the second test sample (i.e. the second test sample that was moved under aperture 126 in step 608). Steps 604 and 608 are then repeated as described above, recording the animal's response to the second test sample (or the system is re-set in step 606 if the second sample is not sampled/recorded). In step 608, a third test sample is then positioned below aperture 126. If it is determined that the specified criterion number of responses has still not been reached, step 612 will re-set the analysis session back to step 602, and the sequence will continue. This loop (time sequence 1, time sequence 2, time sequence 2A and time sequence 3 as designated in flowchart 600) will continue until the specified criterion number of responses are recorded (i.e. sampled/recorded by the animal).
In step 610, once the specified number of operant responses are recorded, (i.e. the last requisite sample is sampled and recorded in step 608) the house lights are turned off, the signal light 110, B, is turned off, and the animal is rewarded, for example through the use of food hopper 130, water dipper, and/or other means for rewarding the animal. For example, 5 test samples may be required to be sampled and recorded by the animal in order to reach the specified number of criterion responses. Any number of responses though can be used as the criterion for determining when the animal is rewarded or the analysis is complete (e.g, 1, 2, 3, 4, 5, 10, 15, 20, 30, 40, 50, etc. samples/responses).
Once the animal has been rewarded, the analysis session then enters time sequence 2B as shown in flowchart 600. In step 614, the animal reward means is closed, and a counter is advanced by 1, indicating the successful completion of one test session (i.e. sampling and recording of the requisite number of samples). In steps 616 and 618, it is determined whether or not the criteria of the complete analysis session have been reached. For example, if the analysis session is designed to test a total of 50 samples, and the specified criterion number of responses required for the animal to be rewarded (step 610) is set at 5, then 10 total test sessions are required to complete the full analysis session (i.e. 10 sets of 5 animal sampling/responses). In the case where the entire analysis session has not been completed (i.e. all 50 samples), step 616 then resets the analysis session back to step 602 (time sequence 3) and the sampling/response analysis discussed above is repeated. If it is determined that the entire analysis session has been completed, step 618 then signals that the session is to be ended, in step 620.
The apparatus and methods described herein therefore allow for an animal to sample and analyze a large number of samples in a very rapid manner. For example, if a 96 well plate is used as sample support means, 96 total samples can be analyzed by a single animal (or multiple animals if desired) in a single analysis session. For example, the specified criterion number of responses required for the animal to be rewarded can be set at 4 (or any number). Thus, the animal will be rewarded after the completion of every 4 samples sampled/recorded. The system is then reset in steps 614-616 until 24 iterations are completed (i.e. 4×24=96 total samples). The analysis system and apparatus can be used to sample any number of samples, e.g., 2, 3, 4, 5, 10, 20, 30, 40, 50, 100, 200, 300, etc., using the iterative methods and apparatus described herein.
The use of sample support means such as sample plate 104 (e.g., a 6, 12, 24, 48, 96, 192 or 384 well sample plate) allows a user to utilize very small sample sizes in various sensory discrimination analyses. For example, in the case of liquid samples, sample sizes on the order of 10's to 100's of microliters can be used (or larger volumes can be used as well). This is highly advantageous for samples that may be expensive or difficult to produce in large quantities. This volume (e.g., 10 μL) in the well of a 96 well sample plate though, is more than adequate for an animal to sample and record a sensory response. In addition to liquid samples, solid samples can also be used in the various apparatus and methods described herein.
While taste discrimination is one example of a sensory analysis that can be performed using the methods and apparatus described herein, additional sensory discrimination tests can also be performed. For example, olfactory sensory discrimination can be tested by using a sample support means that comprises large/deep wells 106, thereby allowing larger amounts of volatile samples to be used to facilitate analysis by the animal. Additionally, tactile and/or visual sensory discrimination is amenable to this apparatus.
The apparatus and methods described herein can also be used for selective delivery of food or medicine to an animal. For example, the apparatus and methods can be used to selectively move the sample support means and support platform relative to one another and/or move the movable partition to reveal a specific type of food or medicine to an animal at a predetermined time, or predetermined amounts at various times. The apparatus and methods described herein can also be used in various other discrimination settings beyond sensory discrimination. For example, the effects of one or more pharmaceuticals, toxins, or other agents can be assessed using the various systems and methods described herein.
As shown in
For example, as shown in
The actions of an animal sampling a test substance in well 106 are detected by detector 703 as a result of changes in determining means 702. For example, while sampling the one or more samples, an animal may disrupt determining means 702 with its tongue, snout, or paw. Such disruptions are subsequently detected by detector 703 and then quantified by a quantifier 706. Examples of quantifiers include computers, calculators, counters, and the like. The temporary disruption of determining means 702 can occur once, or more than once (e.g., 2, 5, 10, 20, 50, 100, etc., times), and can be detected and quantified by various quantifiers 706 known to those skilled in the art, such as counters, computers, calculators, etc.
As shown in
In step 1102, (with reference to
In step 1106, it is then determined when an animal samples the first test sample. Any suitable means for determining when an animal samples the samples may be used, such as those described herein, as well as additional means known to those skilled in the art. As shown in
Animal induced light disruptions are then detected by detector 703 and subsequently optionally quantified in step 1107 by a quantifier 706. Any suitable means for determining and quantifying when the animal samples the samples may be used, such as those described herein, as well as additional means known to those skilled in the art.
In step 1108, movable partition 128 is then moved so as to conceal aperture 126 in support platform 102. In step 1110, sample plate 104 and support platform 102 are moved relative to each other, thereby positioning a subsequent test sample in subsequent sample well 106 below aperture 126 in support platform 102, for example by using motion table 118.
In step 1112, movable partition 128 is moved to reveal the subsequent test sample in subsequent sample well 106. In step 1114, the animal is signaled that the subsequent test sample in the sample well is available for sampling. It should be understood that steps 1112 and 1114 of respectively moving the movable partition to reveal the subsequent test sample, and signaling the animal that the subsequent test sample is available for sampling, can occur in any order. In step 1116, it is determined when an animal samples the subsequent sample as set forth above. In step 1117, the number of times the animal samples the subsequent sample can be quantified.
In step 1118, steps 1108 through 1116 are repeated until all test samples have been sampled by the animal. After all test samples have been sampled by the animal (i.e., constituting a completed analysis session), the animal is optionally rewarded in step 1120, for example, by allowing the animal to eat from food hopper 130. In additional embodiments, flowchart 1100 can optionally comprise rewarding the animal in step 1122 after it has provided a response to the first sample in step 1106. In still further embodiments, the animal can be optionally rewarded following the completion of each and every sample, or a select number of samples, as desired, during the analysis session.
It is to be noted that the disclosed apparatus can operate according to a variety of disclosed methodologies alone or in combination with other disclosed methodologies. For example, while animals can be rewarded from the food hopper 130 for performing trained sensory discrimination actions as described in
It will be readily apparent to one skilled in the relevant arts that other suitable modifications and adaptations to the methods and applications described herein can be made without departing from the scope of the disclosure or any embodiment thereof. The examples presented herein are for purposes of illustration, and not limitation. Alternatives (including equivalents, extensions, variations, deviations, etc., of those described herein) will be apparent to persons skilled in the relevant art(s) based on the teachings contained herein. Such alternatives fall within the scope and spirit of the disclosure.
