This work was supported by a Grant-in-Aid for JSPS Fellows to A.A.; by Grants-in-Aid for Scientific Research on Innovative Areas for JSPS Fellows (No. 4501 and No. 25132712) to T.K.; and by a research project grant awarded by Azabu University. Figure 2 is reprinted from Kihara, T., Harada, T., &#38; Koshida, N. Wafer-compatible fabrication and characteristics of nanocrystalline silicon thermally induced ultrasound emitters. In: Sensors and Actuators A: Physical, volume 125, Elsevier, p. 426, (2006), with permission from Elsevier.

All procedures were approved by the Ethics Committee of Azabu University. All experiments were carried out in a soundproof chamber.
1. Animal Preparation
<ol>
	<li>Males for Recording
	<ol>
		<li>Obtain sexually mature male&#160;mice experienced in mating.</li>
	</ol>
	</li>
	<li>Female Subjects
	<ol>
		<li>Obtain virgin female mice that have been housed with 2 to 5 littermates per cage (usually 8 - 12 weeks old).</li>
		<li>Obtain vaginal smears daily to determine the phase of the estrous cycle before the test, according to McLean21. Care should be taken to minimize the vaginal stimulation to avoid pseudopregnancy.</li>
		<li>Stain the smears with Giemsa, and determine phase of the estrous cycle based on the presence or absence of leukocytes, cornified epithelial cells, and nucleated epithelial cells, according to Nelson22.</li>
	</ol>
	</li>
</ol>
2. Devices (Figure 1)
<img alt="Figure 1" src="/files/ftp_upload/53074/53074fig1.jpg" /> 
Figure 1.&#160;Schematic of the Two-choice Test Box and Devices. Mice can access rooms A and B through the small gates located between them and the neutral zone. The two-choice box and two ultrasound emitters are placed on the floor of a soundproof chamber. The microphone is suspended inside the soundproof chamber. Abbreviation: PC, personal computer. <a href="https://www.jove.com/files/ftp_upload/53074/53074fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<ol>
	<li>For Recording
	<ol>
		<li>Connect an ultrasonic condenser microphone to a PC using a USB A/D converter.</li>
		<li>Set the gain level of the A/D converter to &#8220;7&#8221;.</li>
		<li>Record acoustic data in 16-bit format files with a sampling rate of 400 kHz using audio capture software.</li>
	</ol>
	</li>
	<li>For Playback
	<ol>
		<li>Connect a D/A converter to the PC using a USB interface.</li>
		<li>Connect two amplifiers to the D/A converter through an attenuator. (The latter device serves to prevent overload.)</li>
		<li>Connect an ultrasound emitter to each amplifier.</li>
	</ol>
	</li>
</ol>
3. USV Recording
<ol>
	<li>Place a male mouse in a small- (17 x 10 x 11 cm) or medium-sized (21 x 14 x 13 cm) cage with a 6 cm-diameter hole in the sidewall and the hole covered with a 0.5 cm wire mesh. When using a medium-sized cage, construct a partition across the center of the cage to reduce the area.</li>
	<li>Do not use bedding in the cage to avoid rustling noises that could contaminate the recordings.</li>
	<li>Place a microphone beside the mesh.</li>
	<li>Begin ultrasonic vocalization monitoring with the recording setup shown in step 2.1.</li>
	<li>Place a sexually mature female mouse in either metestrus or diestrus in the cage with the male mouse.</li>
	<li>Record USVs for 3 &#8211; 5 min.</li>
</ol>
4. Test Box
<ol>
	<li>Build the test box using acrylic board (Figure 1). 
	Note: The test box (35 x 20, and x 20 cm high) is divided in three compartments: a neutral zone (15 x 20 cm), and rooms A and B (20 x 10 cm, each). Rooms A and B each have a 4 cm-diameter hole that is covered with a 0.5cm wire mesh. The holes and mesh are located at each end of rooms A and B. Make gates (5 x 5 cm each) between the neutral zone and rooms A and B.</li>
	<li>To prevent sound leakage insulate each ultrasound emitter, except for the side facing the mesh, using rubber plates, sealing them to the box around the perimeter of each mesh.</li>
	<li>Place lead seals on both sides of the wall between rooms A and B for sound insulation.</li>
</ol>
5. Preparing for Sound Playback
<ol>
	<li>Creation of Playback Sounds
	<ol>
		<li>Capture a 20 sec segment of USV from the recorded file using digital audio editing software.</li>
		<li>Select and capture background noise (0.35 sec) from the 20 sec USV segment file. Create a 20 sec background noise file by repeating the noise segment.</li>
		<li>To play back the two sound files simultaneously, export them as a single stereo sound file, with one file for the &#8220;left ear&#8221; and the other file for the &#8220;right ear.&#8221;</li>
		<li>Filter the sound files using as high-pass filter with a cutoff of 40 kHz.</li>
		<li>Reduce noise using the noise-reduction tool in post-processing software. Select and capture a segment of the file that contains no USVs as the noise-reduction profile, and run noise reduction with level 40.</li>
	</ol>
	</li>
	<li>Calibration of Playback Sounds
	<ol>
		<li>Ensure that the space between ultrasound emitters and microphone is 10 cm.</li>
		<li>To calibrate sound pressure levels from the ultrasound emitters, perform ultrasonic monitoring using the configuration described in Step 2.1. Measure the sound pressure level by the microphone in decibels (dB).</li>
		<li>Using the attenuator and amplifiers, adjust the volume of the USVs generated by the ultrasound emitters to the same sound pressure level as the male USVs recorded in Step 3.</li>
		<li>When using the two ultrasound emitters and a sound file composed of USVs and background noise, confirm that the two ultrasound emitters exhibit the same sound pressure level using a calibration sound (e.g., a 75-kHz pure tone) before performing the behavioral test.</li>
		<li>When reproducing a sound file composed of two streams of USVs, adjust the two generated sound pressure levels to the same level, before testing.</li>
	</ol>
	</li>
</ol>
6. Two-choice Test
<ol>
	<li>Place the ultrasound emitters behind the meshes of the test box.</li>
	<li>Close the gates to rooms A and B with an acrylic board, and habituate the female subject to the neutral zone for 30 min. Cover the box with acrylic board to avoid that the mouse can escape.</li>
	<li>Start video recording using a CCD camera mounted above the box. The camera (not shown in Figure 1) covers the area of all three compartments.</li>
	<li>Remove the gate and cover-board and allow the female to explore freely the test box, including the sound zones.</li>
	<li>Once the female has investigated both meshes, and has returned to the neutral zone, start playing a 20 sec sound file repeatedly for 5 or 10 min.</li>
	<li>Conduct behavioral monitoring for 5 or 10 min.</li>
	<li>To reduce undesired olfactory cues deposited from the previous subject, clean the test cages between the tests with 70% ethanol.</li>
	<li>Switch the place of ultrasound emitters A and B randomly to avoid inherent side bias effect towards rooms A or B.</li>
</ol>
7. Statistical Analyses
<ol>
	<li>Using behavioral event-scoring software, analyze the following parameters: total number of entries in each room; total duration of stay in each middle zone; total duration of stay in each sound zone; and total duration of search of each mesh in front of ultrasound emitter. Figure 1 illustrates what is meant by &#8220;middle zone&#8221; and &#8220;sound zone.&#8221; 
	Note: In cases where the mouse stays on the dividing line between the two zones (Figure 1, dashed line) decide the location by the direction of the head. When the head faces the mesh side, it is scored as a stay in the sound zone.</li>
	<li>For each behavioral parameter, compare responses for rooms A and B using a Wilcoxon signed-rank test, or paired t-tests with a significance level of 0.05.</li>
</ol>

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The authors declare that they have no competing interests.

Here, the results of a representative test showed that female mice can discriminate between artificial male USVs and background noise (Figure 3). The conclusion to be drawn from these results is that the discrimination signal is reflected in the duration of stay in the room and sound zone, and in the duration of searching the mesh in the first 5 min of testing, but not in the second 5 min (Figure 3C, E and F). These data indicate that mice become habituated to the playback sounds, possib...

Many animals use vocalizations for intraspecific communication. In the mouse Mus musculus, one important type of communication signal is ultrasonic vocalizations (USVs), which have frequencies higher than 20 kHz. USVs emitted by mice are considered a component of social recognition in male-female1-4, female-female1, 5, and male-male1, 6 interactions. USVs are also emitted by pups when they are isolated from their mother, which increases her pup-retrieving behavior, and therefore pup survival 7. Although many reports have analyzed and categorized mouse USVs8,9, the behavioral responses and neural mechanisms of the receiving animal have been less documented10, 11. The latter is necessary to clarify the biological significance of the various characteristics of USVs. To reveal these mechanisms, the playback experiment is an efficient method. Recent playback studies have revealed that female mice are attracted to USVs12, and that they prefer USVs from males that are different from their parents13, 14.
This article explains the playback test used to evaluate USV preference in mice. A two-choice test box was developed in which two different USVs can be played back simultaneously in two compartments of a test enclosure, as shown in Figure 1. This type of test box prevents sound contamination by dividing the test area in three sub-chambers, using lead walls. The ultrasound emitters are located outside each room. In the wall between the rooms and ultrasound emitters are holes covered with wire mesh. Mice can move freely in the three rooms, and show a &#8220;searching the mesh&#8221; behavior, as if to respond to USVs played back by the ultrasound emitters. In this test, mice stay for periods of different duration close to one sound emitter or the other. These parameters can be logged to obtain a sensitive measure of sound preference.
To play the USVs back, nanocrystalline silicon thermo-acoustic emitters (i.e., &#8220;nc-Si emitter&#8221;) were used as in previous studies15-17. These devices are composed of a thin-film heater electrode, a nano-porous silicon layer, and a single-crystalline silicon wafer. The digital sound file is converted to an analog signal and then passed through the heater electrode. The device converts the resulting voltage-dependent thermal signals into significant sound pressure with low distortion. This device is unique in that, unlike common sound generators that depend on mechanical vibrations, it can reproduce sound without the need of a diaphragm. The emitter exhibits a flat sound pressure level at frequencies from 20 to 160 kHz (Figure 2), and can reproduce digitally recorded murine USVs very accurately in terms of duration, frequency, and sound pressure level15, 18, 19.
In a representative experiment shown in Figure 3, C57BL/6 (B6) females were allowed to choose between BALB/c (BALB) male USVs and background noise. In addition, Figure 4 shows the choice of B6 and BALB females between simultaneous USV playbacks from a BALB and a B6 male, as reported in a previous study14. The characteristics of male USVs differ between B6 and BALB strains20. As shown by these results, the attractiveness of USVs can be assessed with the present protocol, in which sounds are recorded from a live individual, acoustically analyzed, and played back to other individuals.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>Soundproof chamber</td>
			<td>Muromachi Kikai</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Small cage</td>
			<td>CLEA Japan</td>
			<td>CL-0113-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Middle cage</td>
			<td>CLEA Japan</td>
			<td>CL-0103-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Ultrasound condenser microphones</td>
			<td>Avisoft Bioacoustics</td>
			<td>CM16/CMPA</td>
			<td></td>
		</tr>
		<tr>
			<td>A/D converter</td>
			<td>Avisoft Bioacoustics</td>
			<td>UltraSoundGate116H</td>
			<td></td>
		</tr>
		<tr>
			<td>Audio software</td>
			<td>Avisoft Bioacoustics</td>
			<td>RECORDER USGH</td>
			<td></td>
		</tr>
		<tr>
			<td>Adobe Audition 3.0 / Audio editing software</td>
			<td>Adobe Systems</td>
			<td>Adobe Audition 3.0</td>
			<td></td>
		</tr>
		<tr>
			<td>Nc-Si emitter</td>
			<td>Original</td>
			<td></td>
			<td>not commercially available but it is planned to be so in near future</td>
		</tr>
		<tr>
			<td>D/A converter</td>
			<td>National Instruments</td>
			<td>NI USB-6251 BNC</td>
			<td></td>
		</tr>
		<tr>
			<td>Attenuator</td>
			<td>Original</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Amplifier</td>
			<td>Yamatake</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>PC</td>
			<td>Windows 7 professional</td>
			<td></td>
			<td>Intel&#174; core i7-2600K CPU @ 3.4GHz, 8GB RAM, 64-bit operating system</td>
		</tr>
		<tr>
			<td>Event recorder Excel-macro / Event-scoring software</td>
			<td>original</td>
			<td></td>
			<td>Programmed by Naoto Akagawa &#38; Takeru Yamamoto</td>
		</tr>
		<tr>
			<td>CCD Camera</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Rubber plates (made of elastomer resin)</td>
			<td>Tokyo bouon</td>
			<td>TI-75BK B4</td>
			<td>Cut them to the proper size http://www.piano-bouon.jp/shopping/?pid=1329272401-447630&#38;ca=6&#38;p=3</td>
		</tr>
		<tr>
			<td>Giemsa&#39;s azur eosin methylene blue solution</td>
			<td>Merck Millipore</td>
			<td>1.09204.0500</td>
			<td></td>
		</tr>
	</tbody>
</table>

determining ultrasonic vocalization preferences in mice using a two-choice playback test

Mice emit ultrasonic vocalizations (USVs) during a variety of conditions, such as pup isolation and adult social interactions. These USVs differ with age, sex, condition, and genetic background of the emitting animal. Although many studies have characterized these differences, whether receiver mice can discriminate among objectively different USVs and show preferences for particular sound traits remains to be elucidated. To determine whether mice can discriminate between different characteristics of USVs, a playback experiment was developed recently, in which preference responses of mice to two different USVs could be evaluated in the form of a place preference.
First, USVs from mice were recorded. Then, the recorded USVs were edited, trimmed accordingly, and exported as stereophonic sound files. Next, the USV amplitudes generated by the two ultrasound emitters used in the experiment were adjusted to the same sound pressure level. Nanocrystalline silicon thermo-acoustic emitters were used to play the USVs back. Finally, to investigate the preference of subject mice to selected USVs, pairs of two differing USV signals were played back simultaneously in a two-choice test box. By repeatedly entering a defined zone near an ultrasound emitter and searching the wire mesh in front of the emitter, the mouse reveals its preference for one sound over another. This model allows comparing the attractiveness of the various features of mouse USVs, in various contexts.

The USVs recorded from one BALB-male (161 syllables per 20 sec), as well as background noise were used as playback sounds in the representative experiment shown in Figure 3. In this experiment, 7 female B6 mice were used at 9 weeks of age. To determine the best duration of testing of female response to playback sounds, the behavioral parameters were analyzed separately for the first and last five min of the total 10 min test time.
First, there was no significant difference in ...

Watch this Scientific Journal Video about Determining Ultrasonic Vocalization Preferences in Mice using a Two-choice Playback Test at JoVE.com

Determining Ultrasonic Vocalization Preferences in Mice using a Two-choice Playback Test

Ultrasonic vocalizations (USVs) in mice differ depending on age, sex, condition, and genetic background. Using two ultrasound emitters broadcasting simultaneously in different locations, this two-choice test can evaluate murine recognition and preference responses to different characteristics of USVs.

Mice emit ultrasonic vocalizations (USVs) during a variety of conditions, such as pup isolation and adult social interactions. These USVs differ with age, ...

determining-ultrasonic-vocalization-preferences-mice-using-two-choice

Research

JoVE Journal

Behavior

11.0K Views.  Azabu University. Ultrasonic vocalizations (USVs) in mice differ depending on age, sex, condition, and genetic background. Using two ultrasound emitters broadcasting simultaneously in different locations, this two-choice test can evaluate murine recognition and preference responses to different characteristics of USVs.

Video: Determining Ultrasonic Vocalization Preferences in Mice using a Two-choice Playback Test

The Successive Alleys Test of Anxiety in Mice and Rats

The plus-maze was derived from the early work of Montgomery. He observed that rats tended to avoid the open arms of a maze, preferring the enclosed ones. Handley, Mithani and File et al. performed the first studies on the plus-maze design we use today, and in 1987 Lister published a design for use with mice. 
Time spent on, and entries into, the open arms are an index of anxiety; the lower these indices, the more anxious the mouse is. Alternatively, a mouse that spends most of its time in the closed arms is classed as anxious. 
One of the problems of the plus-maze is that, while time spent on, and entries into, the open arms is a fairly unambiguous measure of anxiety, time in the central area is more difficult to interpret, although time spent here has been classified as &#x201C;decision making&#x201D;. In many tests central area time is a considerable part of the total test time.
Shepherd et al. produced an ingenious design to eliminate the central area, which they called the &#x201C;zero maze&#x201D;. However, although used by several groups, it has never been as widely adopted as the plus-maze. 
In the present article I describe a modification of the plus-maze design that not only eliminates the central area but also incorporates elements from other anxiety tests, such as the light-dark box and emergence tests. It is a linear series of four alleys, each having increasing anxiogenic properties. It has given similar results to the plus-maze in general. Although it may not be more sensitive than the plus-maze (more data is needed before a firm conclusion can be reached on this point), it provides a useful confirmation of plus-maze results which would be useful when, for example, only a single example of a mutant mouse was available, as, for example, in ENU-based mutagenesis programs.

The plus-maze measures anxiety-like behaviour in rodents. There are two opposite closed and two opposite open arms; anxious rodents avoid the open arms. The central area is neither completely open nor closed, so time spent here is ambiguous and difficult to interpret. Here a modification of the plus-maze protocol eliminating this area is described.

The plus-maze was derived from the early work of Montgomery. He observed that rats tended to avoid the open arms of a maze, preferring the enclosed ones.  ...

Contextual and Cued Fear Conditioning Test Using a Video Analyzing System in Mice

The contextual and cued fear conditioning test is one of the behavioral tests that assesses the ability of mice to learn and remember an association between environmental cues and aversive experiences. In this test, mice are placed into a conditioning chamber and are given parings of a conditioned stimulus (an auditory cue) and an aversive unconditioned stimulus (an electric footshock). After a delay time, the mice are exposed to the same conditioning chamber and a differently shaped chamber with presentation of the auditory cue. Freezing behavior during the test is measured as an index of fear memory. To analyze the behavior automatically, we have developed a video analyzing system using the ImageFZ application software program, which is available as a free download at http://www.mouse-phenotype.org/. Here, to show the details of our protocol, we demonstrate our procedure for the contextual and cued fear conditioning test in C57BL/6J mice using the ImageFZ system. In addition, we validated our protocol and the video analyzing system performance by comparing freezing time measured by the ImageFZ system or a photobeam-based computer measurement system with that scored by a human observer. As shown in our representative results, the data obtained by ImageFZ were similar to those analyzed by a human observer, indicating that the behavioral analysis using the ImageFZ system is highly reliable. The present movie article provides detailed information regarding the test procedures and will promote understanding of the experimental situation.

This article presents a protocol for a contextual and cued fear conditioning test using a video analyzing system to assess fear learning and memory in mice.

The contextual and cued fear conditioning test is one of the behavioral tests that assesses the ability of mice to learn and remember an association ...

The Modified Hole Board - Measuring Behavior, Cognition and Social Interaction in Mice and Rats

This protocol describes the modified hole board (mHB), which combines features from a traditional hole board and open field and is designed to measure multiple dimensions of unconditioned behavior in small laboratory mammals (e.g., mice, rats, tree shrews and small primates). This paradigm is a valuable alternative for the use of a behavioral test battery, since a broad behavioral spectrum of an animal&#8217;s behavioral profile can be investigated in one single test.
The apparatus consists of a box, representing the &#8216;protected&#8217; area, separated from a group compartment. A board, on which small cylinders are staggered in three lines, is placed in the center of the box, representing the &#8216;unprotected&#8217; area of the set-up. The cognitive abilities of the animals can be measured by baiting some cylinders on the board and measuring the working and reference memory. Other unconditioned behavior, such as activity-related-, anxiety-related- and social behavior, can be observed using this paradigm. Behavioral flexibility and the ability to habituate to a novel environment can additionally be observed by subjecting the animals to multiple trials in the mHB, revealing insight into the animals&#8217; adaptive capacities.
Due to testing order effects in a behavioral test battery, na&#239;ve animals should be used for each individual experiment. By testing multiple behavioral dimensions in a single paradigm and thereby circumventing this issue, the number of experimental animals used is reduced. Furthermore, by avoiding social isolation during testing and without the need to food deprive the animals, the mHB represents a behavioral test system, inducing if any, very low amount of stress.

This protocol describes the modified hole board, which is a behavioral test set-up that comprises the characteristics of an open field and a traditional hole board. This set-up enables the differential analysis of unconditioned behavior of small laboratory mammals as well as the analysis of cognitive abilities.

This protocol describes the modified hole board (mHB), which combines features from a traditional hole board and open field and is designed to measure ...

The Social Dimension of Stress: Experimental Manipulations of Social Support and Social Identity in the Trier Social Stress Test

In many situations humans are influenced by the behavior of other people and their relationships with them. For example, in stressful situations supportive behavior of other people as well as positive social relationships can act as powerful resources to cope with stress. In order to study the interplay between these variables, this protocol describes two effective experimental manipulations of social relationships and supportive behavior in the laboratory. In the present article, these two manipulations are implemented in the Trier Social Stress Test (TSST)&#8212;a standard stress induction paradigm in which participants are subjected to a simulated job interview. More precisely, we propose (a) a manipulation of the relationship between different protagonists in the TSST by making a shared social identity salient and (b) a manipulation of the behavior of the TSST-selection committee, which acts either supportively or unsupportively. These two experimental manipulations are designed in a modular fashion and can be applied independently of each other but can also be combined. Moreover, these two manipulations can also be integrated into other stress protocols and into other standardized social interactions such as trust games, negotiation tasks, or other group tasks.

Previous research on the social dimension of stress has focused on two important variables: social identity and social support. This protocol introduces an effective experimental manipulation of these two social variables and describes their implementation in a standard stress induction paradigm (Trier Social Stress Test).

In many situations humans are influenced by the behavior of other people and their relationships with them. For example, in stressful situations ...

Eliciting and Analyzing Male Mouse Ultrasonic Vocalization (USV) Songs

Mice produce ultrasonic vocalizations (USVs) in a variety of social contexts throughout development and adulthood. These USVs are used for mother-pup retrieval1, juvenile interactions2, opposite and same sex interactions3,4,5, and territorial interactions6. For decades, the USVs have been used by investigators as proxies to study neuropsychiatric and developmental or behavioral disorders7,8,9, and more recently to understand mechanisms and evolution of vocal communication among vertebrates10. Within the sexual interactions, adult male mice produce USV songs, which have some features similar to courtship songs of songbirds11. The use of such multisyllabic repertoires can increase potential flexibility and information they carry, as they can be varied in how elements are organized and recombined, namely syntax. In this protocol a reliable method to elicit USV songs from male mice in various social contexts, such as exposure to fresh female urine, anesthetized animals, and estrus females is described. This includes conditions to induce a large amount of syllables from the mice. We reduce recording of ambient noises with inexpensive sound chambers, and present a quantification method to automatically detect, classify and analyze the USVs. The latter includes evaluation of call-rate, vocal repertoire, acoustic parameters, and syntax. Various approaches and insight on using playbacks to study an animal&#39;s preference for specific song types are described. These methods were used to describe acoustic and syntax changes across different contexts in male mice, and song preferences in female mice.

Eliciting and Analyzing Male Mouse Ultrasonic Vocalization USV Songs

Mice produce a complex multisyllabic repertoire of ultrasonic vocalizations (USVs). These USVs are widely used as readouts for neuropsychiatric disorders. This protocol describes some of the practices we learned and developed to consistently induce, collect, and analyze the acoustic features and syntax of mouse songs.

Mice produce ultrasonic vocalizations (USVs) in a variety of social contexts throughout development and adulthood. These USVs are used for mother-pup ...

Psychophysical Tracking Method to Measure Taste Preferences in Children and Adults

The Monell two-series, forced-choice, paired-comparison tracking method provides a reliable measure of sweet taste preferences from childhood to adulthood. The method, which is identical for children, adolescents, and adults, is of short duration (&#60; 15 min), does not rely on sustained attention or place demands on memory (which would yield spurious age differences), and minimizes the impact of language development, making this method amenable to the cognitive limitations of pediatric populations. In this whole-mouth tasting method, subjects are asked to taste (without swallowing) pairs of solutions of different sucrose concentrations and to point to the solution they prefer. Each subsequent pair contains the participant&#39;s preceding preferred concentration and an adjacent stimulus concentration. The procedure continues until the subject chooses either a given concentration of sucrose when paired with both a higher and a lower concentration, or the highest or lowest concentration two consecutive times. Subjects are prevented from reaching response criteria on the basis of first or second position bias by the two-series design of the method, which counterbalances the order of solution presentation within each pair between the series (the weaker concentration is presented first in Series 1, second in Series 2). The geometric mean of the two sucrose concentrations chosen in Series 1 and 2 is an estimate of the participant&#39;s most preferred level of sucrose. Sucrose preference as determined with this laboratory-based measure has been shown to be associated with preference for sugars in foods and beverages and with taste receptor genotype, family history of alcoholism, and race/ethnicity, as well as depressive symptomatology among pediatric populations. The method has real-world relevance and has been applied to determine most preferred level of other tastes (e.g., salt), making it a valuable psychophysical tool.

Sweet taste has powerful hedonic appeal among people of all ages, particularly children. Described herein is a reliable and valid method that can be used to determine the level of sweetness most preferred, making it a valuable psychophysical tool for scientists.

The Monell two-series, forced-choice, paired-comparison tracking method provides a reliable measure of sweet taste preferences from childhood to ...

The Rodent Psychomotor Vigilance Test (rPVT): A Method for Assessing Neurobehavioral Performance in Rats and Mice

The human Psychomotor Vigilance Test (PVT) is a widely used procedure for measuring changes in fatigue and sustained attention. The present article describes a rodent version of the PVT&#8212;termed the &#34;rPVT&#34;&#8212;that measures similar aspects of attention (i.e., performance accuracy, motor speed, premature responding, and lapses in attention). Data are presented that demonstrate both the short- and long-term usefulness of the rPVT when employed with laboratory rats. Rats easily learn the rPVT, and learning to perform the basic procedure takes less than two weeks of training. Once acquired, rat performances in the rPVT show a high degree of similarity to these same performance measures in the human PVT, including similarities in, lapses in attention, reaction times, vigilance decrements across session time (i.e., the human &#34;time-on-task&#34; effects), and the response-stimulus interval (RSI) effect described for humans. Thus the rPVT can be an extremely valuable tool for assessing the effects of a wide range of variables on sustained attention quite similar to human PVT performances, and thus can be useful for developing novel treatments for neurobehavioral dysfunctions.

The Rodent Psychomotor Vigilance Test rPVT: A Method for Assessing Neurobehavioral Performance in Rats and Mice

A rat version of the human Psychomotor Vigilance Test (PVT) is described that measures aspects of attention similar to those measured with the human PVT, including aspects of human vigilance such as performance accuracy, motor speed, premature responding, and lapses in attention.

The human Psychomotor Vigilance Test (PVT) is a widely used procedure for measuring changes in fatigue and sustained attention. The present article ...

Novel Object Recognition Test for the Investigation of Learning and Memory in Mice

The object recognition test (ORT) is a commonly used behavioral assay for the investigation of various aspects of learning and memory in mice. The ORT is fairly simple and can be completed over 3 days: habituation day, training day, and testing day. During training, the mouse is allowed to explore 2 identical objects. On test day, one of the training objects is replaced with a novel object. Because mice have an innate preference for novelty, if the mouse recognizes the familiar object, it will spend most of its time at the novel object. Due to this innate preference, there is no need for positive or negative reinforcement or long training schedules. Additionally, the ORT can also be modified for numerous applications. The retention interval can be shortened to examine short-term memory, or lengthened to probe long-term memory. Pharmacological intervention can be used at various times prior to training, after training, or prior to recall to investigate different phases of learning (i.e., acquisition, early or late consolidation, or recall). Overall, the ORT is a relatively low-stress, efficient test for memory in mice, and is appropriate for the detection of neuropsychological changes following pharmacological, biological, or genetic manipulations.

The object recognition test (ORT) is a simple and efficient assay for evaluating learning and memory in mice. The methodology is described below.

The object recognition test (ORT) is a commonly used behavioral assay for the investigation of various aspects of learning and memory in mice. The ORT is ...

Reinstatement of Drug-seeking in Mice Using the Conditioned Place Preference Paradigm

The present protocol describes the Conditioned Place Preference (CPP) as a model of relapse in drug addiction. In this model, animals are first trained to acquire a conditioned place preference in a drug-paired compartment, and after the post-conditioning test, they perform several sessions to extinguish the established preference. The CPP permits the evaluation of the conditioned rewarding effects of drugs related to environmental cues. Then, the extinguished CPP can be robustly reinstated by the non-contingent administration of a priming dose of the drug, and by exposure to stressful stimuli. Both methods will be explained here. When the animal reinitiates the behavioral response, a reinstatement of the conditioned reward is considered to have taken place.
The main advantages of this protocol are that it is non-invasive, inexpensive, and simple with good validity criteria. In addition, it allows the study of different environmental manipulations, such as stress or diet, which can modulate relapse into drug seeking behaviors. However, one limitation is that if the researcher aims to explore the motivation and primary reinforcing effects of the drug, it should be complemented with self-administration procedures, as they involve operant responses of animals.

This protocol describes the Conditioned Place Preference (CPP) as a model of relapse. This procedure permits the measurement of relapse in laboratory animals, considering the impact of drug-associated environmental cues as craving and relapse in abstaining addicts is currently the focus of drug-abuse treatment programs.

The present protocol describes the Conditioned Place Preference (CPP) as a model of relapse in drug addiction. In this model, animals are first trained to ...

Assessment of Social Transmission of Food Preferences Behaviors

Olfactory recognition deficits are suggested to be able to serve as clinical marker to differentiate Alzheimer&#39;s disease (AD) subjects from healthy aging groups. For example, olfactory dysfunction in AD can present as impairment in olfactory recognition, emerging during early stages of the disease and worsening while the disease progresses. The social transmission of food preferences (STFP) task is based on a rudimentary form of communication between rodents concerning distant foods dependent on the transmission of olfactory cues. Healthy wild-type mice would prefer to eat a novel, flavored food that was previously cued by a conspecific, and this food preference would be hampered in transgenic AD mice, such as the APP/PS1 model. Indeed, a strong preference for the cued food in C57Bl6/J mice of 3 months of age was found, and this was reduced in 3 months old transgenic APP/PS1 mice. In summary, STFP task could be a powerful measure to be integrated in present subclinical detection assays of AD.

This paper presents a protocol for the investigation of social transmission of food preference in mice. The advantages and possible applications for this procedure, for instance, in detecting early changes in AD mouse models, are highlighted. To conclude, interpretation of the results in light of critical details are discussed.

Olfactory recognition deficits are suggested to be able to serve as clinical marker to differentiate Alzheimer&#39;s disease (AD) subjects from healthy ...