This research was supported by the Israel Science Foundation (grant No. 738/11), by the National Institute for Psychobiology in Israel (NIPI-7-2011-12), and by the Open University Foundation

NOTE: All experimental protocols were approved by the International Committee for Animal Care and Use in Israel. All efforts were made to minimize the number of animals used and their suffering.
1. Preparation for the Forced Swim Test
<ol>
	<li>Use two adjacent rooms. Use one room as a &#8220;waiting room&#8221; for holding the animals prior to behavioral testing, and the other for carrying out the procedure.</li>
	<li>Prepare transparent cylindrical glass containers (the only restriction for the number of containers is the space available) measuring 50 cm in height and a diameter of 20 cm. 
	NOTE: It is possible to run several animals simultaneously in the same room. If so, separate the containers from one another using a dark screen so that the animals will not see each other during the procedure.</li>
	<li>Prepare video camera(s) in front of the containers so that every camera perceives one or more containers in a way that will allow the clear observation of the animals&#8217; behavior later on while viewing the footage.</li>
	<li>Prepare clean drying cages, heat lamps and heat pads for the animals that have finished the procedure to avoid hypothermia. Make sure the bottom of the cage has blotting paper and change it when it gets wet. Do not place the cages in the testing room. 
	NOTE: Make sure not to mix animals from different home cages while they are staying in the transient drying cages.</li>
</ol>
2. Animal Handling Prior to Testing
<ol>
	<li>House animals in a room with a 12 hr light/dark cycle.</li>
	<li>During the days of the experimental procedure give the animals free access to food and water, except for the specific time spent in the procedure room.</li>
	<li>When using rats, handle the animals for about 2 min daily, 5 days prior to the beginning of the experimental procedure.</li>
</ol>
3. Training Procedure
The procedure is carried out differently for rats and mice.
NOTE: For both mice and rats, watch the animals while they are in the water at all times. In case an animal appears in serious distress (e.g. very tired, cannot stay up float) remove the animal from the water and exclude it from the experiment.
<ol>
	<li>For mice &#8212; There is one session 6 min long, divided into pretest (the first 2 min) and test (the last 4 min).
	<ol>
		<li>In order for the mice to get acclimated to the testing environment, transport the animals in their home cages at least 30 min prior to behavioral testing to the waiting room.</li>
		<li>Fill the cylinders with tap water at 25 &#176;C and adjust the water depth according to the mouse&#8217; size, so that it cannot touch the bottom of the container with its hind legs.</li>
		<li>Mark the cylinder with the animal number for the purpose of the identification of the animal later on while viewing the footage.</li>
		<li>Turn on the video camera/s and then place each mouse in the water filled cylinder container for 6 min.</li>
		<li>After 6 min have elapsed, turn the camera/s off, remove the mouse from the container and place it in the transient drying cage with the heat lamp above it and the heat pad under it.&#160;The mice should be closely and continuously monitored while recovering in this cage. For this purpose it is possible to place a thermometer at the level of the mice to make sure the temperature in the cage does not exceed 37 &#176;C. Also, place the cage such that not all of it falls under the lamp or over the pad; this allows the mouse to move to a cooler area if desired.</li>
		<li>Change the water after every session to avoid any influence on the next mouse.</li>
	</ol>
	</li>
	<li>For rats &#8212; There are 2 sessions, 24 hr apart. The first session is the pre-test stage (15 min) and the second session is the test stage (5 min).
	<ol>
		<li>In order for the rats to get acclimated to the testing environment, transport the animals in their home cages at least 30 min prior to behavioral testing to the waiting room.</li>
		<li>Fill the cylinders with tap water at 23 &#177; 1 &#176;C and adjust the water depth according to the rat&#8217;s size, so that it cannot touch the bottom of the container with its hind legs.</li>
		<li>Mark the cylinder with the animal number for the purpose of the identification of the animal later on while viewing the footage.</li>
		<li>Place each rat in the water filled cylinder container for 15 min.</li>
		<li>After 15 min have elapsed remove the rat from the container and place it in the transient drying cage with the heat lamp above it and the heat pad under it.&#160;The rat should be closely and continuously monitored while recovering in this cage. For this purpose it is possible to place a thermometer at the level of the rat to make sure the temperature in the cage does not exceed 37 &#176;C. Also, place the cage such that not all of it falls under the lamp or over the pad; this allows the rat to move to a cooler area if desired.</li>
		<li>Change the water after every session to avoid any influence on the next rat. 
		NOTE: This is the end of the pretest stage.</li>
		<li>Twenty-four hours later, in order for the rats to get acclimated to the testing environment, transport the animals in their home cages at least 30 min prior to behavioral testing to the waiting room.</li>
		<li>Fill the cylinders with tap water at 23 &#177; 1 &#176;C and adjust the water depth according to the rat&#8217;s size, so that it cannot touch the bottom of the container with its hind legs.</li>
		<li>Mark the cylinder with the animal number for the purpose of the identification of the animal later on while viewing the footage.</li>
		<li>Turn on the video camera/s and then place the rat in the water filled cylinder container for 5 min. Make sure that each rat is tested in the same container and position in the room as the previous day.</li>
		<li>After 5 min have elapsed turn the camera/s off, remove the rat from the container and place it in the transient drying cage with the heat lamp above it and the heat pad under it.&#160;The rat should be closely and continuously monitored while recovering in this cage. For this purpose it is possible to place a thermometer at the level of the rat to make sure the temperature in the cage does not exceed 37 &#176;C. Also, place the cage such that not all of it falls under the lamp or over the pad; this allows the rat to move to a cooler area if desired.</li>
		<li>Change the water after every session to avoid any influence on the next rat. 
		NOTE: This is the end of the test stage.</li>
	</ol>
	</li>
</ol>
4. The Behavioral Coding
For mice, code the last 4 min defined as the test stage. For rats, code the 5 min of the test stage.
<ol>
	<li>Code the duration of time spent as &#8220;Immobile&#8221; if the mouse is floating with the absence of any movement except for those necessary for keeping the nose above water.</li>
	<li>Code the duration of time spent as &#8220;Struggling/climbing&#8221; if quick movements of the forelimbs are observed such that the front paws break the surface of the water.</li>
	<li>Code the duration of time spent as &#8220;Swimming&#8221; if movement of forelimbs or hind limbs in a paddling fashion is observed. 
	NOTE: It is possible to use an alternative way to code these behaviors, this includes a time-sampling method. Rate the swimming, struggling or immobility as the frequency of episodes at 5 sec intervals throughout the test session.</li>
</ol>

The authors have nothing to disclose.

The FST is used to monitor depressive-like behavior and is based on the assumption that immobility reflects a measure of behavioral despair 3. The main advantages of this procedure lie in its relatively easy operation and fast results. Moreover, its sensitivity to a broad range of antidepressant drugs that makes it a suitable screening test is one of the most important features leading to its high predictive validity 29. Importantly, this test can also differentiate between drugs that are not aimed ...

Depression is a life-threatening psychiatric disorder and a major public health concern worldwide with an incidence of 5% and a lifetime prevalence of 15-20%. Moreover, it is estimated that by 2020 depression will be in the top three contributors to the burden of disease1,2. Depression is associated with disability, decreased quality of life, increased health-related costs and is considered a main risk factor for many diseases, including cardiovascular, metabolic and neuropsychiatric disorders3,4.Current pharmaco-therapeutic treatments have limited efficacy and are associated with many deleterious side effects5,6. Therefore, a better understanding of the pathophysiology of this disorder alongside with the development of innovative and improved treatments remains crucial. Hence, animal models are essential for advancing research in this field.
There are many models used for the study of this disorder (e.g. sucrose preference test, tail suspension test) with the forced swimming test (FST, also known as Porsolt&#8217;s test after the developer of this model 7,8) being one of the most commonly used assays 7,9-12.
During the FST an animal is placed in a container filled with water from which it cannot escape. The animal will first try to escape but eventually will exhibit immobility (i.e. floating with the absence of any movement except for those necessary for keeping the nose above water). The FST is a very popular model in animal research for a number of reasons. First, it involves the exposure of the animals to stress, which was shown to have a role in the tendency for major depression 12-14. Moreover depression is often viewed as a lack of ability to handle with stress 15-17. Second, pharmacological treatment with antidepressants prior to the test has been shown to reduce immobility in the FST 18-23. Therefore, it is often used as a screening assay for novel compounds with potential antidepressant properties 15-17,24. Additionally, the FST has been shown to share some of the factors that are influenced or altered by depression in humans, such as changes in food consumption, sleep abnormalities and drug-withdrawal-induced anhedonia 15-17,24. This is also the reason why this test is sometimes used to evaluate depressive-like behavior in mutant mice, with increase or decrease in basal immobility (compared to &#8216;wild-type&#8217; mice) 25,26.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Name of Material/ Equipment</td>
			<td style="width:80px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:387px;">Comments/Description</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">Computer</td>
			<td>Dell</td>
			<td></td>
			<td>intel(r) core(tm) i3-2120 cpu @ 3.30ghz, 4GB ram</td>
			<td></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">Camera</td>
			<td>VIDO</td>
			<td>AU-CB422</td>
			<td>B/W CCD CAMERA&#160; 
			http://www.vido-europe.com/products_detail.asp?id=33&#38;pcategory=2</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">Coding software</td>
			<td>Biobserve</td>
			<td></td>
			<td>FST Analysis 
			http://www.biobserve.com/products/fst/index.html</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">Heating lamp</td>
			<td>Ikea</td>
			<td>AA-19025-3</td>
			<td>ESPRESSIVIO 400.504.46&#160;- 20W G4 Bulb&#160; 
			http://www.ikea.com/ms/en_US/customer_service/assembly/E/E00050467.pdf</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">Heating&#160;pillow</td>
			<td>Sachs</td>
			<td>EF-188B</td>
			<td>38*38cm Heating&#160;pillow 
			http://www.sachs.co.il/eng/lego_tree.php?instance_id=21&#38;actions=show&#38;id= 
			604</td>
		</tr>
	</tbody>
</table>

the forced swim test as a model of depressive-like behavior

The goal of the present protocol is to describe the forced swim test (FST), which is one of the most commonly used assays for the study of depressive-like behavior in rodents. The FST is based on the assumption that when placing an animal in a container filled with water, it will first make efforts to escape but eventually will exhibit immobility that may be considered to reflect a measure of behavioral despair. This test has been extensively used because it involves the exposure of the animals to stress, which was shown to have a role in the tendency for major depression. Additionally, the FST has been shown to share some of the factors that are influenced or altered by depression in humans, including changes in food consumption, sleep abnormalities and drug-withdrawal-induced anhedonia. The main advantages of this procedure are that it is relatively easy to perform and that its results are easily and quickly analyzed. Moreover, its sensitivity to a broad range of antidepressant drugs that makes it a suitable screening test is one of the most important features leading to its high predictive validity. Despite its appeal, this model has a number of disadvantages. First, the issue of chronic augmentation is problematic in this test because in real life patients need to be treated for at least several weeks before they experience any relief from their symptoms. Last, due to the aversiveness of the FST, it is important to take into account possible influences it might have on brain structure/function if brain analyses are to be carried out following this procedure.

The following results are based on unpublished data from our lab. In this experiment, adult ICR female mice were tested after 3 weeks of treatment with the selective serotonin reuptake Inhibitor (SSRI) escitalopram or novel herbal anti-depressive and anti-anxiety treatment (NHT) (for additional information regarding the herbal treatment, see 12,27,28). One-way ANOVA revealed that the treatment reduced depressive-like behavior in the FST [F(2,58) = 4.88, p &#60;0.05]. One-sided Dunnet analysis revealed that tre...

Watch this Scientific Journal Video about The Forced Swim Test as a Model of Depressive-like Behavior at JoVE.com

The Forced Swim Test as a Model of Depressive-like Behavior

This protocol describes the forced swim test, which is used for the study of depressive-like behavior in rodents. This procedure involves placing an animal in a container filled with water that eventually will lead to the exhibition of immobility behavior, which is considered to reflect behavioral despair.

The goal of the present protocol is to describe the forced swim test (FST), which is one of the most commonly used assays for the study of depressive-like ...

the-forced-swim-test-as-a-model-of-depressive-like-behavior

Research

JoVE Journal

Behavior

36.7K vues.  Tel-Aviv University. This protocol describes the forced swim test, which is used for the study of depressive-like behavior in rodents. This procedure involves placing an animal in a container filled with water that eventually will lead to the exhibition of immobility behavior, which is considered to reflect behavioral despair.

Vidéo: The Forced Swim Test as a Model of Depressive-like Behavior

The Resident-intruder Paradigm: A Standardized Test for Aggression, Violence and Social Stress

This video publication explains in detail the experimental protocol of the resident-intruder paradigm in rats. This test is a standardized method to measure offensive aggression and defensive behavior in a semi natural setting. The most important behavioral elements performed by the resident and the intruder are demonstrated in the video and illustrated using artistic drawings. The use of the resident intruder paradigm for acute and chronic social stress experiments is explained as well. Finally, some brief tests and criteria are presented to distinguish aggression from its more violent and pathological forms.

This video shows the resident-intruder paradigm in rats. This test is a standardized method to measure offensive aggression, defensive behavior and violence in a semi-natural setting. The use of the paradigm for social stress experiments is explained as well.

This video publication explains in detail the experimental protocol of the resident-intruder paradigm in rats. This test is a standardized method to ...

Assessment of Murine Exercise Endurance Without the Use of a Shock Grid: An Alternative to Forced Exercise

Using laboratory mouse models, the molecular pathways responsible for the metabolic benefits of endurance exercise are beginning to be defined. The most common method for assessing exercise endurance in mice utilizes forced running on a motorized treadmill equipped with a shock grid. Animals who quit running are pushed by the moving treadmill belt onto a grid that delivers an electric foot shock; to escape the negative stimulus, the mice return to running on the belt. However, avoidance behavior and psychological stress due to use of a shock apparatus can interfere with quantitation of running endurance, as well as confound measurements of postexercise serum hormone and cytokine levels. Here, we demonstrate and validate a refined method to measure running endurance in na&#239;ve C57BL/6 laboratory mice on a motorized treadmill without utilizing a shock grid. When mice are preacclimated to the treadmill, they run voluntarily with gait speeds specific to each mouse. Use of the shock grid is replaced by gentle encouragement by a human operator using a tongue depressor, coupled with sensitivity to the voluntary willingness to run on the part of the mouse. Clear endpoints for quantifying running time-to-exhaustion for each mouse are defined and reflected in behavioral signs of exhaustion such as splayed posture and labored breathing. This method is a humane refinement which also decreases the confounding effects of stress on experimental parameters.

A method to assess exercise endurance in laboratory mice without the use of a shock grid is demonstrated. This method is a humane refinement that can decrease the confounding effects of stress on experimental parameters.

Using laboratory mouse models, the molecular pathways responsible for the metabolic benefits of endurance exercise are beginning to be defined. The most ...

The Use of the Puzzle Box as a Means of Assessing the Efficacy of Environmental Enrichment

Environmental enrichment can dramatically influence the development and function of neural circuits. Further, enrichment has been shown to successfully delay the onset of symptoms in models of Huntington&#8217;s disease 1-4, suggesting environmental factors can evoke a neuroprotective effect against the progressive, cellular level damage observed in neurodegenerative disorders. The ways in which an animal can be environmentally enriched, however, can vary considerably. Further, there is no straightforward manner in which the effects of environmental enrichment can be assessed: most methods require either fairly complicated behavioral paradigms and/or postmortem anatomical/physiological analyses. This protocol describes the use of a simple and inexpensive behavioral assay, the Puzzle Box 5-7 as a robust means of determining the efficacy of increased social, sensory and motor stimulation on mice compared to cohorts raised in standard laboratory conditions. This simple problem solving task takes advantage of a rodent&#8217;s innate desire to avoid open enclosures by seeking shelter. Cognitive ability is assessed by adding increasingly complex impediments to the shelter&#8217;s entrance. The time a given subject takes to successfully remove the obstructions and enter the shelter serves as the primary metric for task performance. This method could provide a reliable means of rapidly assessing the efficacy of different enrichment protocols on cognitive function, thus paving the way for systematically determining the role specific environmental factors play in delaying the onset of neurodevelopmental and neurodegenerative disease.

Environmental enrichment provides a potential protective effect against neurodegenerative disorders. Currently, however, there is no easy way of determining the efficacy of enrichment procedures. This protocol describes a simple &#8220;Puzzle Box&#8221; method for assessing an animal&#8217;s cognitive function, in order to reveal the effectiveness of environmental enrichment.

Environmental enrichment can dramatically influence the development and function of neural circuits.  Further, enrichment has been shown to successfully ...

Signal Attenuation as a Rat Model of Obsessive Compulsive Disorder

In the signal attenuation rat model of obsessive-compulsive disorder (OCD), lever-pressing for food is followed by the presentation of a compound stimulus which serves as a feedback cue. This feedback is later attenuated by repeated presentations of the stimulus without food (without the rat emitting the lever-press response). In the next stage, lever-pressing is assessed under extinction conditions (i.e., no food is delivered). At this stage rats display two types of lever-presses, those that are followed by an attempt to collect a reward, and those that are not. The latter are the measure of compulsive-like behavior in the model. A control procedure in which rats do not experience the attenuation of the feedback cue serves to distinguish between the effects of signal attenuation and of extinction. The signal attenuation model is a highly validated model of OCD and differentiates between compulsive-like behaviors and behaviors that are repetitive but not compulsive. In addition the measures collected during the procedure eliminate alternative explanations for differences between the groups being tested, and are quantitative, unbiased and unaffected by inter-experimenter variability. The major disadvantages of this model are the costly equipment, the fact that it requires some technical know-how and the fact that it is time-consuming compared to other models of OCD (11 days). The model may be used for detecting the anti- or pro-compulsive effects of pharmacological and non-pharmacological manipulations and for studying the neural substrate of compulsive behavior.

The goal of the protocol described in this paper is to induce compulsive-like behavior in rats for the study of obsessive-compulsive disorder (OCD). This behavior is precipitated by attenuating a signal indicating that a lever-press response was effective in producing food.

In the signal attenuation rat model of obsessive-compulsive disorder (OCD), lever-pressing for food is followed by the presentation of a compound stimulus ...

Paw-Dragging: a Novel, Sensitive Analysis of the Mouse Cylinder Test

The cylinder test is routinely used to predict focal ischemic damage to the forelimb motor cortex in rodents. When placed in the cylinder, rodents explore by rearing and touching the walls of the cylinder with their forelimb paws for postural support. Following ischemic injury to the forelimb sensorimotor cortex, rats rely more heavily on their unaffected forelimb paw for postural support resulting in fewer touches with their affected paw which is termed forelimb asymmetry. In contrast, focal ischemic damage in the mouse brain fails to result in comparable consistent deficits in forelimb asymmetry. While forelimb asymmetry deficits are infrequently observed, mice do demonstrate a novel behaviour post stroke termed &#8220;paw-dragging&#8221;. Paw-dragging is the tendency for a mouse to drag its affected paw along the cylinder wall rather than directly push off from the wall when dismounting from a rear to a four-legged stance. We have previously demonstrated that paw-dragging behaviour is highly sensitive to small cortical ischemic injuries to the forelimb motor cortex. Here we provide a detailed protocol for paw-dragging analysis. We define what a paw-drag is and demonstrate how to quantify paw-dragging behaviour. The cylinder test is a simple and inexpensive test to administer and does not require pre-training or food deprivation strategies. In using paw-dragging analysis with the cylinder test, it fills a niche for predicting cortical ischemic injuries such as photothrombosis and Endothelin-1 (ET-1)-induced ischemia &#8211; two models that are ever-increasing in popularity and produce smaller focal injuries than middle cerebral artery occlusion. Finally, measuring paw-dragging behaviour in the cylinder test will allow studies of functional recovery after cortical injury using a wide cohort of transgenic mouse strains where previous forelimb asymmetry analysis has failed to detect consistent deficits.

Classical forelimb asymmetry analysis of the cylinder test is routinely used to assess behavioural deficits in rats following brain injury or stroke; however, it fails to detect consistent deficits in mice. This study demonstrates that quantifying paw-dragging behaviour is a more sensitive analysis of brain injury in mice.

The cylinder test is routinely used to predict focal ischemic damage to the forelimb motor cortex in rodents. When placed in the cylinder, rodents explore ...

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 ...

The 4 Mountains Test: A Short Test of Spatial Memory with High Sensitivity for the Diagnosis of Pre-dementia Alzheimer's Disease

This protocol describes the administration of the 4 Mountains Test (4MT), a short test of spatial memory, in which memory for the topographical layout of four mountains within a computer-generated landscape is tested using a delayed match-to-sample paradigm. Allocentric spatial memory is assessed by altering the viewpoint, colors and textures between the initially presented and target images.
Allocentric spatial memory is a key function of the hippocampus, one of the earliest brain regions to be affected in Alzheimer&#39;s disease (AD) and impairment of hippocampal function predates the onset of dementia. It was hypothesized that performance on the 4MT would aid the diagnosis of predementia AD, which manifests clinically as Mild Cognitive Impairment (MCI).
The 4MT was applied to patients with MCI, stratified further based on cerebrospinal fluid (CSF) AD biomarker status (10 MCI biomarker positive, 9 MCI biomarker negative), and with mild AD dementia, as well as healthy controls. Comparator tests included tests of episodic memory and attention widely accepted as sensitive measures of early AD. Behavioral data were correlated with quantitative MRI measures of the hippocampus, precuneus and posterior cingulate gyrus.
4MT scores were significantly different between the two MCI groups (p = 0.001), with a test score of &#8804;8/15 associated with 100% sensitivity and 78% specificity for the classification of MCI with positive AD biomarkers, i.e., predementia AD. 4MT test scores correlated with hippocampal volume (r = 0.42) and cortical thickness of the precuneus (r = 0.55).
In conclusion, the 4MT is effective in identifying the early stages of AD. The short duration, easy application and scoring, and favorable psychometric properties of the 4MT fulfil the need for a simple but accurate diagnostic test for predementia AD.

The 4 Mountains Test: A Short Test of Spatial Memory with High Sensitivity for the Diagnosis of Pre-dementia Alzheimer&#039;s Disease

This article describes the 4 Mountains Test (4MT), a hippocampus-dependent test of working allocentric spatial memory. The hippocampus is affected early in Alzheimer's disease (AD) and this article outlines the 4MT methodology and results of patient testing, which demonstrates the value of the 4MT in the diagnosis of pre-dementia AD.

This protocol describes the administration of the 4 Mountains Test (4MT), a short test of spatial memory, in which memory for the topographical layout of ...

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 ...

A Method to Test the Effect of Environmental Cues on Mating Behavior in Drosophila melanogaster

An individual's sexual drive is influenced by genotype, experience and environmental conditions. How these factors interact to modulate sexual behaviors remains poorly understood. In Drosophila melanogaster, environmental cues, such as food availability, affect mating activity offering a tractable system to investigate the mechanisms modulating sexual behavior. In D. melanogaster, environmental cues are often sensed via the chemosensory gustatory and olfactory systems. Here, we present a method to test the effect of environmental chemical cues on mating behavior. The assay consists of a small mating arena containing food medium and a mating couple. The mating frequency for each couple is continuously monitored for 24 h. Here we present the applicability of this assay to test environmental compounds from an external source through a pressurized air system as well as manipulation of the environmental components directly in the mating arena. The use of a pressurized air system is especially useful to test the effect of very volatile compounds, while manipulating components directly in the mating arena can be of value to ascertain a compound's presence. This assay can be adapted to answer questions about the influence of genetic and environmental cues on mating behavior and fecundity as well as other male and female reproductive behaviors.

A Method to Test the Effect of Environmental Cues on Mating Behavior in Drosophila melanogaster

We demonstrate an assay to analyze the environmental and genetic cues that influence mating behavior in the fruit fly Drosophila melanogaster.

An individual's sexual drive is influenced by genotype, experience and environmental conditions. How these factors interact to modulate sexual behaviors ...

A Two-interval Forced-choice Task for Multisensory Comparisons

We provide a procedure for a psychophysics experiment in humans based on a previously described paradigm aimed to characterize the perceptual duration of intervals within the range of milliseconds of visual, acoustic, and audiovisual aperiodic trains of six pulses. In this task, each of the trials consists of two consecutive intramodal intervals where the participants press the upward arrow key to report that the second stimulus lasted longer than the reference, or the downward arrow key to indicate otherwise. The analysis of the behavior results in psychometric functions of the probability of estimating the comparison stimulus to be longer than the reference, as a function of the comparison intervals. In conclusion, we advance a way of implementing standard programming software to create visual, acoustic, and audiovisual stimuli, and to generate a two-interval forced-choice (2IFC) task by delivering stimuli through noise-blocking headphones and a computer&#39;s monitor.

Psychophysics is essential for studying perception phenomena through sensory information. Here we present a protocol to perform a two-interval forced-choice task as implemented in a previous report on human psychophysics where participants estimated the duration of visual, auditory, or audiovisual intervals of aperiodic trains of pulses.

We provide a procedure for a psychophysics experiment in humans based on a previously described paradigm aimed to characterize the perceptual duration of ...