This work was funded by grants of the Swiss National Science Foundation (Grant 31003A-149315-1 to M.E.S. and Grant IZK0Z3-150809 to A.Z.), to A.Z. the Heidi Demetriades Foundation, to M.E.S. the European Research Council (&#8216;Nogorise&#8217;) and the Christopher and Dana Reeve Foundation (CDRF).

All experiments were performed in accordance with the guidelines of the Veterinary Office of the Canton Zurich, Switzerland.
1. Animal Handling and Habituation
<ol>
	<li>Animal Handling 
	Note: 5 days prior to the start of the experiment, perform step 1.1.1 daily.
	<ol>
		<li>For behavioral experiments, accustom the animals to the experimenter. Have daily handling sessions lasting 10-15 min per animal. Clean the box after each animal&#8217;s session.
		<ol>
			<li>Initially, place the experimenter&#8217;s hand into a cage allowing the animal to explore and smell to become familiarized with the experimenter.</li>
			<li>Next, gently lift the animal with the experimenter&#8217;s hand in a safe manner by grasping the rat&#8217;s body between the front- and hind paws allowing further familiarization.</li>
		</ol>
		</li>
		<li>Weigh each animal daily to obtain a baseline bodyweight before food deprivation.</li>
	</ol>
	</li>
	<li>Apparatus Habituation and Food Familiarization
	<ol>
		<li>Weigh each animal daily to obtain a baseline bodyweight before food deprivation.</li>
		<li>Start food depriving rats 3 days prior to the beginning of pre-training on a standard laboratory diet. Give rats 0.05 g of food per 1 g bodyweight per day (e.g., a rat weighing 200 g, start with 10 g of food). Ensure bodyweight to not decrease more than 10% per day by monitoring bodyweight daily.
		<ol>
			<li>If several animals are held in one cage, dominant rats may eat more than less dominant ones. In case the bodyweight of an animal decreases, feed the animal separately instead of group feeding. Give water ad libitum.</li>
		</ol>
		</li>
		<li>To acquaint the rat with the grasping apparatus, place the animal into the training box (Figure 1). Have sugar pellets placed in the training box in proximity to the slit opening to familiarize the animal with the food pellets. Perform this step 10-15 min daily for 3 days.</li>
	</ol>
	</li>
</ol>
2. Pre-training and Motor Skill Learning
<ol>
	<li>Pre-training
	<ol>
		<li>One day after familiarization, place the animal into the training box and place the pellet closely to the slit opening so it can be reached by the animal&#8217;s tongue. Exclude animals that retrieve pellets with their forelimb during pre-training 
		Note: At this stage, pellet retrieval with the tongue is crucial and usually the animal&#8217;s method of choice. Pellets should be in no case grasped with the forelimb until the first day of motor skill learning to allow adequate monitoring of the learned reaching task. Pellet retrieval with the forelimb during pre-training is an exclusion criterion and is in most cases not observed.</li>
		<li>Teach the rat to either run to the rear of the cage and return to the slit opening or step back and turn around its own axis in order to receive the next food pellet with the tongue. Allow time for the animal to explore the cage, run to the rear and return to the slit opening. If the animal does not correctly execute the task, use a forceps to gently tap at the end rear of the cage and catch the animal&#8217;s attention. Once the animal is at the rear, gently tap at the cage front to guide the animal to the slit opening. 
		Note: Once the animal reaches a defined standard value (e.g., 50 successful pellet retrievals with the tongue in less than 15 min), the animal qualifies for the motor skill learning stage. On day 1 and 2 of pre-training, learners can already be distinguished from non-learners. Non-learners can be excluded from the study at this step. This decreases the probability of having a high number of non-learners during the motor learning step (2.2).</li>
		<li>During pre-training, food deprive rats on a standard laboratory diet. Give water ad libitum. Monitor body weight daily throughout the study. Do not use same room to train male and female rats. Ensure a calm and noise-free environment for the animal.</li>
	</ol>
	</li>
	<li>Determination of Paw Preference and Motor Skill Learning
	<ol>
		<li>During the first session of motor skill learning, replace the slide in front of the window with a post. Place the sugar pellet about 1.5 cm away from the window on the post so that the animal cannot reach the pellet with its tongue but only retrieve it by a precise forelimb reaching and grasping movement.
		<ol>
			<li>To enforce pellet retrieval by the forelimb, use a forceps to gently bring the pellet close to the animal&#8217;s mouth and retract the pellet while the animal attempts consumption with the tongue. Carry out this task repetitively until the animal stretches out the forelimb and grasps a pellet.</li>
		</ol>
		</li>
		<li>Place the post central to the window opening. To determine paw preference, carefully observe the first 10 trials on training day 1. More than 70% of the reaching attempts (i.e., 7 out of 10) have to be executed with the same forelimb. If this is not achieved, continue with another round of 10 trials until the 70% threshold is reached.</li>
		<li>After paw preference determination, shift the post towards the preferred forelimb and align central to the border of the window opening. Preferred paw alignment means the post is shifted contrary to the respective paw to allow an optimal angle for reaching (Figure 1B, C).</li>
		<li>Classify a trial, defined as a new pellet presented to the animal, as successful (reach, grasp, retrieve and eat the pellet), drop (reach, grasp and lose pellet during retrieval) or fail (knock pellet off the post). Note down every trial in your sheet and analyse the data after the experiment.</li>
		<li>Perform one daily session consisting of a defined number of trials (e.g., 150) or a maximum time (e.g., 1 hr) for each animal.</li>
		<li>Investigate precision and fine-tuning of the movement using first attempt analysis. A first attempt is defined by grasping of the pellet in a single monolithic movement without disruption, hesitation or repetition of individual movement components. Carefully observe each grasp by the rat.
		<ol>
			<li>If the rat hesitates or retracts during a reach or attempts several trials to correctly grasp the pellet, note the respective trial as success but not first attempt. If the animal successfully grasps the pellet in a single monolithic reach, note down the respective trial as successful first attempt in a separate column in your sheet.</li>
		</ol>
		</li>
		<li>During motor skill learning, food deprive rats on a standard laboratory diet. Give water ad libitum. Monitor body weight daily throughout the study.</li>
	</ol>
	</li>
</ol>

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The authors have nothing to disclose

The paradigm shown in this study is adapted from Buitrago et al.18 and differs from the classical single pellet reaching paradigm17 mainly in two aspects:
First, studying within-session improvement allows analysis of the learned task within a single day, which can provide a different level of information such as investigation of the fast learning component compared to the slow learning component represented by the average daily values (see Figures 3</stro...

Movement control is a core function of the central nervous system (CNS). Motricity is the main measurable output of CNS function and the main possibility for individuals to interact with the external world. Understanding the principles of motor function and the mechanisms that underlie the learning of a motor task is currently one of the big challenges in neuroscience. Morphological, physiological and molecular changes were found upon acquisition of a new motor task. For example, the shape and number of synapses change in response to skilled motor training1-5, and functional changes of the synaptic machinery were observed after motor learning. Synaptic responses were higher in the connections of the forelimb-representing region of the trained motor cortex compared to the untrained hemisphere of the same animal or to responses from untrained animals6,7. Electrophysiological observations also suggest that long-term potentiation (LTP) and long-term depression (LTD) like mechanisms take place during the learning of a new motor skill, and that the range of synaptic operation, which is defined between the limiting borders of LTP and LTD saturation, is modified8. Furthermore, it has been shown that activity markers and plasticity promoting molecules such as c-fos, GAP-43, or BDNF but also plasticity inhibiting molecules such as Nogo-A display regulatory roles for learning-related neuronal plasticity9-16.
These advances towards a better understanding of the mechanisms underlying motor learning could only be achieved with the use of behavioral paradigms that allow precise control of the acquisition of a new motor skill, e.g., skilled forelimb-reaching. Only a well-structured behavioral task allows to monitor and capture correlative changes that occur upon learning and execution of the respective task. Here we visually demonstrate a modified version of the skilled forelimb single-pellet reaching task in rats adapted from Buitrago et al.17 The presented paradigm allows the analysis of movement acquisition within a daily training session (within-session) representing the fast learning component and primary acquisition as well as skilled motor learning over several sessions (between-session) representing the slow learning component and maintenance of the learned task18. Importantly, this behavioral paradigm increases the degree of difficulty and complexity of the motor skill task due to two features: First, the rats are trained to turn around their axis after each grasp and thus to realign their body prior to the next pellet reach and renew the body orientation, preventing constant movement execution from the same angle. Second, pellets are retrieved from a vertical post placed in front of the cage. Due to the small diameter of the post, pellets can easily be kicked off requiring a precise grasp for successful retrieval and preventing simple pulling of the pellet towards the animal.
Such complex behavioral testing allows deeper insights into the mechanisms underlying motor learning. Compared to mice, rats are superior in their performance of complex behavioral tasks and thus better suited for complex paradigms as presented in this study. Considering the increasing genetic possibilities available for rats19,20, the combination of precise and well controlled behavioral testing methods with genetic manipulations, imaging and physiological techniques represents a powerful toolbox to better understand the neurobiological basis of motor learning and memory.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>1</td>
			<td>Training Box</td>
			<td>Self Made</td>
			<td></td>
		</tr>
		<tr>
			<td>2</td>
			<td>Pedestal</td>
			<td>Self Made</td>
			<td></td>
		</tr>
		<tr>
			<td>3</td>
			<td>Sugar Pellets</td>
			<td colspan="2">45-mg dustless precision pellets, TSE Systems Intl. Group</td>
		</tr>
		<tr>
			<td>4</td>
			<td>Animals</td>
			<td>5-6 week old Sprague Dawley Male Rats</td>
			<td></td>
		</tr>
		<tr>
			<td>5</td>
			<td>Laptop</td>
			<td>Hewlett Packard</td>
			<td></td>
		</tr>
		<tr>
			<td>6</td>
			<td>Stop Watch</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>7</td>
			<td>Forceps</td>
			<td>Fine Science Tools (FST)</td>
			<td></td>
		</tr>
		<tr>
			<td>8</td>
			<td>Software</td>
			<td>Excel (Microsoft), GraphPad Prism (GraphPad)</td>
			<td></td>
		</tr>
		<tr>
			<td>9</td>
			<td>Weighing scale</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>10</td>
			<td>Counter</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

acquisition of a high-precision skilled forelimb reaching task in rats

Movements are the main measurable output of central nervous system function. Developing behavioral paradigms that allow detailed analysis of motor learning and execution is of critical importance in order to understand the principles and processes that underlie motor function. Here we present a paradigm to study movement acquisition within a daily session of training (within-session) representing the fast learning component and primary acquisition as well as skilled motor learning over several training sessions (between-session) representing the slow learning component and consolidation of the learned task. This behavioral paradigm increases the degree of difficulty and complexity of the motor skill task due to two features: First, the animal realigns its body prior to each pellet retrieval forcing renewed orientation and preventing movement execution from the same angle. Second, pellets are grasped from a vertical post that matches the diameter of the pellet and is placed in front of the cage. This requires a precise grasp for successful pellet retrieval and thus prevents simple pulling of the pellet towards the animal. In combination with novel genetics, imaging and electrophysiological technologies, this behavioral method will aid to understand the morphological, anatomical and molecular underpinnings of motor learning and memory.

Successful motor skill acquisition is only achieved through consistent practice. Despite careful consideration of all aspects, some rats fail to learn the task (Figure 2). These &#39;non-learners&#39; either lack motivation resulting in few or absent attempts of pellet retrieval from the start of the experiment or generally lose interest in reaching for the pellets leading to continuously failed attempts. By contrast, some animals show aggressive and over-motivated behavior resulting in overhasty and rus...

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Acquisition of a High-precision Skilled Forelimb Reaching Task in Rats

A paradigm is presented to analyze the acquisition of a high-precision skilled forelimb reaching task in rats.

Movements are the main measurable output of central nervous system function. Developing behavioral paradigms that allow detailed analysis of motor ...

acquisition-of-a-high-precision-skilled-forelimb-reaching-task-in-rats

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10.2K 조회수.  University of Zurich. A paradigm is presented to analyze the acquisition of a high-precision skilled forelimb reaching task in rats.

비디오: Acquisition of a High-precision Skilled Forelimb Reaching Task in Rats

The Crossmodal Congruency Task as a Means to Obtain an Objective Behavioral Measure in the Rubber Hand Illusion Paradigm

The rubber hand illusion (RHI) is a popular experimental paradigm. Participants view touch on an artificial rubber hand while the participants' own hidden hand is touched. If the viewed and felt touches are given at the same time then this is sufficient to induce the compelling experience that the rubber hand is one's own hand. The RHI can be used to investigate exactly how the brain constructs distinct body representations for one's own body. Such representations are crucial for successful interactions with the external world. To obtain a subjective measure of the RHI, researchers typically ask participants to rate statements such as "I felt as if the rubber hand were my hand". Here we demonstrate how the crossmodal congruency task can be used to obtain an objective behavioral measure within this paradigm.
The variant of the crossmodal congruency task we employ involves the presentation of tactile targets and visual distractors. Targets and distractors are spatially congruent (i.e. same finger) on some trials and incongruent (i.e. different finger) on others. The difference in performance between incongruent and congruent trials - the crossmodal congruency effect (CCE) - indexes multisensory interactions. Importantly, the CCE is modulated both by viewing a hand as well as the synchrony of viewed and felt touch which are both crucial factors for the RHI.
The use of the crossmodal congruency task within the RHI paradigm has several advantages. It is a simple behavioral measure which can be repeated many times and which can be obtained during the illusion while participants view the artificial hand. Furthermore, this measure is not susceptible to observer and experimenter biases. The combination of the RHI paradigm with the crossmodal congruency task allows in particular for the investigation of multisensory processes which are critical for modulations of body representations as in the RHI.

We demonstrate how an objective measure can be employed in the widely employed rubber hand illusion paradigm. This measure is obtained by modifying the well-established crossmodal congruency task. This task allows the investigation of multisensory processes which are critical for modulations of body representations as in the rubber hand illusion.

The rubber hand illusion (RHI) is a popular experimental paradigm. Participants view touch on an artificial rubber hand while the participants' own hidden ...

A Procedure to Study the Effect of Prolonged Food Restriction on Heroin Seeking in Abstinent Rats

In human drug addicts, exposure to drug-associated cues or environments that were previously associated with drug taking can trigger relapse during abstinence. Moreover, various environmental challenges can exacerbate this effect, as well as increase ongoing drug intake.
The procedure we describe here highlights the impact of a common environmental challenge, food restriction, on drug craving that is expressed as an augmentation of drug seeking in abstinent rats.
Rats are implanted with chronic intravenous i.v. catheters, and then trained to press a lever for i.v. heroin over a period of 10-12 days. Following the heroin self-administration phase the rats are removed from the operant conditioning chambers and housed in the animal care facility for a period of at least 14 days. While one group is maintained under unrestricted access to food (sated group), a second group (FDR group) is exposed to a mild food restriction regimen that results in their body weights maintained at 90% of their nonrestricted body weight. On day 14 of food restriction the rats are transferred back to the drug-training environment, and a drug-seeking test is run under extinction conditions (i.e.&#160;lever presses do not result in heroin delivery).
The procedure presented here results in a highly robust augmentation of heroin seeking on test day in the food restricted rats. In addition, compared to the acute food deprivation manipulations we have used before, the current procedure is a more clinically relevant model for the impact of caloric restriction on drug seeking. Moreover, it might be closer to the human condition as the rats are not required to go through an extinction-training phase before the drug-seeking test, which is an integral component of the popular reinstatement procedure.

A procedure that allows a demonstration of robust augmentation of drug seeking in food-restricted rats is described. Following heroin self-administration training, rats go through an abstinence period, in a drug-free environment, during which they are mildly food restricted. Drug seeking is then tested in the drug-associated environment.

In human drug addicts, exposure to drug-associated cues or environments that were previously associated with drug taking can trigger relapse during ...

Measurement of Fronto-limbic Activity Using an Emotional Oddball Task in Children with Familial High Risk for Schizophrenia

Adolescence is a critical developmental period where the early symptoms of schizophrenia frequently emerge. First-degree relatives of people with schizophrenia who are at familial high risk (FHR) may show similar cognitive and emotional changes. However, the neurological changes underlying the emergence of these symptoms remain unclear. This study sought to identify differences in frontal, striatal, and limbic regions in children and adolescents with FHR using functional magnetic resonance imaging. Groups of 21 children and adolescents at FHR and 21 healthy controls completed an emotional oddball task that relied on selective attention and the suppression of task-irrelevant emotional information. The standard oddball task was modified to include aversive and neutral distractors in order to examine potential group differences in both emotional and executive processing. This task was designed specifically to allow for children and adolescents to complete by keeping the difficulty and emotional image content age-appropriate. Furthermore, we demonstrate a technique for suitable fMRI registration for children and adolescent participants. This paradigm may also be applied in future studies to measure changes in neural activity in other populations with hypothesized developmental changes in executive and emotional processing.

This paper describes how to use the emotional oddball task and fMRI to measure brain activation in children and adolescents at familial high risk for schizophrenia (FHR).&#160;FMRI was used to measure differences in fronto-striato-limbic regions during an emotional oddball task. Children with FHR exhibited abnormal functional activation during adolescence.

Adolescence is a critical developmental period where the early symptoms of schizophrenia frequently emerge. First-degree relatives of people with ...

The 5-Choice Serial Reaction Time Task: A Task of Attention and Impulse Control for Rodents

This protocol describes the 5-choice serial reaction time task, which is an operant based task used to study attention and impulse control in rodents. Test day challenges, modifications to the standard task, can be used to systematically tax the neural systems controlling either attention or impulse control. Importantly, these challenges have consistent effects on behavior across laboratories in intact animals and can reveal either enhancements or deficits in cognitive function that are not apparent when rats are only tested on the standard task. The variety of behavioral measures that are collected can be used to determine if other factors (i.e., sedation, motivation deficits, locomotor impairments) are contributing to changes in performance. The versatility of the 5CSRTT is further enhanced because it is amenable to combination with pharmacological, molecular, and genetic techniques.

This protocol describes the 5-choice serial reaction time task, which is an operant based task used to study attention and impulse control in rodents. Test day challenges, which are modifications of the standard task, increase flexibility of the task and can be combined with other manipulations to more fully characterize behavior.

This protocol describes the 5-choice serial reaction time task, which is an operant based task used to study attention and impulse control in rodents. ...

A Procedure to Observe Context-induced Renewal of Pavlovian-conditioned Alcohol-seeking Behavior in Rats

Environmental contexts in which drugs of abuse are consumed can trigger craving, a subjective Pavlovian-conditioned response that can facilitate drug-seeking behavior and prompt relapse in abstinent drug users. We have developed a procedure to study the behavioral and neural processes that mediate the impact of context on alcohol-seeking behavior in rats. Following acclimation to the taste and pharmacological effects of 15% ethanol in the home cage, male Long-Evans rats receive Pavlovian discrimination training (PDT) in conditioning chambers. In each daily (Mon-Fri) PDT session, 16 trials each of two different 10 sec auditory conditioned stimuli occur. During one stimulus, the CS+, 0.2 ml of 15% ethanol is delivered into a fluid port for oral consumption. The second stimulus, the CS-, is not paired with ethanol. Across sessions, entries into the fluid port during the CS+ increase, whereas entries during the CS- stabilize at a lower level, indicating that a predictive association between the CS+ and ethanol is acquired. During PDT each chamber is equipped with a specific configuration of visual, olfactory and tactile contextual stimuli. Following PDT, extinction training is conducted in the same chamber that is now equipped with a different configuration of contextual stimuli. The CS+ and CS- are presented as before, but ethanol is withheld, which causes a gradual decline in port entries during the CS+. At test, rats are placed back into the PDT context and presented with the CS+ and CS- as before, but without ethanol. This manipulation triggers a robust and selective increase in the number of port entries made during the alcohol predictive CS+, with no change in responding during the CS-. This effect, referred to as context-induced renewal, illustrates the powerful capacity of contexts associated with alcohol consumption to stimulate alcohol-seeking behavior in response to Pavlovian alcohol cues.

A procedure to study the capacity of an alcohol associated environmental context to trigger the renewal of alcohol-seeking behavior in rats is described.

Environmental contexts in which drugs of abuse are consumed can trigger craving, a subjective Pavlovian-conditioned response that can facilitate ...

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 ...

Bouncing Ball with a Uniformly Varying Velocity in a Metronome Synchronization Task

Sensorimotor synchronization (SMS), a fundamental human ability to coordinate movements with external rhythms, has long been thought to be modality specific. In the canonical metronome synchronization task that requires tapping a finger along with an isochronous sequence, a well-established finding is that synchronization is much more stable to an auditory sequence consisting of auditory tones than to a visual sequence consisting of visual flashes. However, recent studies have shown that periodically moving visual stimuli can substantially improve synchronization compared with visual flashes. In particular, synchronization of a visual bouncing ball that has a uniformly varying velocity was found to be not less stable than synchronization of auditory tones. Here, the current protocol describes the application of the bouncing ball with a uniformly varying velocity in a metronome synchronization task. The usage of the bouncing ball in sequences with different inter-onset intervals (IOI) is included. The representative results illustrate synchronization performance of the bouncing ball, as compared with the performances of auditory tones and visual flashes. Given its comparable synchronization performance to that of auditory tones, the bouncing ball is of particular importance for addressing the current research topic of whether modality-specific mechanisms underlay SMS.

The purpose of this protocol is to introduce the application of a bouncing ball with a uniformly varying velocity in a metronome synchronization task.

Sensorimotor synchronization (SMS), a fundamental human ability to coordinate movements with external rhythms, has long been thought to be modality ...

The Knob Supination Task: A Semi-automated Method for Assessing Forelimb Function in Rats

Tasks that accurately measure dexterity in animal models are critical to understand hand function. Current rat behavioral tasks that measure dexterity largely use video analysis of reaching or food manipulation. While these tasks are easy to implement and are robust across disease models, they are subjective and laborious for the experimenter. Automating traditional tasks or creating new automated tasks can make the tasks more efficient, objective, and quantitative. Since rats are less dexterous than primates, central nervous system (CNS) injury produces more subtle deficits in dexterity, however, supination is highly affected in rodents and crucial to hand function in primates. Therefore, we designed a semi-automated task that measures forelimb supination in rats. Rats are trained to reach and grasp a knob-shaped manipulandum and turn the manipulandum in supination to receive a reward. Rats can acquire the skill within 20 &plusmn; 5 days. While the early part of training is highly supervised, much of the training is done without direct supervision. The task reliably and reproducibly captures subtle deficits after injury and shows functional recovery that accurately reflects clinical recovery curves. Analysis of data is performed by specialized software through a graphical user interface that is designed to be intuitive. We also give solutions to common problems encountered during training, and show that minor corrections to behavior early in training produce reliable acquisition of supination. Thus, the knob supination task provides efficient and quantitative evaluation of a critical movement for dexterity in rats.

This manuscript describes a semi-automated task that quantifies supination in rats. Rats reach, grasp, and supinate a spherical manipulandum. The rat is rewarded with a pellet if the turn angle exceeds a criterion set by the user. This task increases throughput, sensitivity to injury, and objectivity compared to traditional tasks.

Tasks that accurately measure dexterity in animal models are critical to understand hand function. Current rat behavioral tasks that measure dexterity ...

Evaluating Skilled Prehension in Mice Using an Auto-Trainer

We describe a method to introduce na&#239;ve mice to a novel prehension (reach-to-grasp) task. Mice are housed singly in cages with a frontal slot that permits the mouse to reach out of its cage and retrieve food pellets. Minimal food restriction is employed to encourage the mice to perform the food retrieval from the slot. As the mice begin to associate coming to the slot for food, the pellets are manually pulled away to stimulate extension and pronation of their paw to grasp and retrieve the pellet through the frontal slot. When the mice begin to reach for the pellets as they arrive at the slot, the behavioral assay can be performed by measuring the rate at which they successfully grasp and retrieve the desired pellet. They are then introduced to an auto-trainer that automates both the process of providing food pellets for the mouse to grasp, and the recording of successful and failed reaching and grasping attempts. This allows for the collection of reaching data for multiple mice with minimal effort, to be used in experimental analysis as appropriate.

Method to assess the impact of training on motor skills is a useful tool. Unfortunately, most behavioral assessments can be labor intensive and/or expensive.We describe here a robotic method of assessing prehension (reach-to-grasp) skill in mice.

We describe a method to introduce na&#239;ve mice to a novel prehension (reach-to-grasp) task. Mice are housed singly in cages with a frontal slot that ...

A Task for Assessing the Impact of a Partner on the Speed and Accuracy of Motor Performance in Rats

To our knowledge, no study has examined the effect of mere presence on accuracy of performance in animals. Therefore, we developed an experimental task to measure rats&#8217; motor performance (speed and accuracy) in a social condition. Rats were trained to run on a runway and pull down a lever at the end of the runway. In testing, rats performed the task solitarily (single) or in the presence of a confederate rat beyond the lever (pair or a social condition). As indices of the performance speed, we measured the time needed to start running, run through the runway, and pull down the lever. As the index of performance accuracy, we counted the number of trials in which rats could pull down the lever during their first attempt. One-way and two-way repeated-measure analyses of variance were used to analyze the data. This run-and-pull task enabled us to examine the effect of the presence of another conspecific on both speed and accuracy of motor performance in one experiment. The results showed that rats performed the task faster but less accurately in pair sessions than in single sessions. This protocol would be a valid animal model to examine the effect of mere presence on speed and accuracy of motor performance in rats.

A procedure to measure the speed and accuracy of rats&rsquo; motor performance in a social condition is described. The protocol enables us to investigate the effect of the mere presence of others on speed and accuracy of motor performance in one experiment.

To our knowledge, no study has examined the effect of mere presence on accuracy of performance in animals. Therefore, we developed an experimental task to ...