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><tbody><tr><td>Training box</td><td></td><td></td><td>Self Made</td></tr><tr><td>Pedestal</td><td></td><td></td><td>Self Made</td></tr><tr><td>Sugar pellets</td><td>TSE Systems Intl. Group</td><td></td><td>45 mg dustless precision pellets</td></tr><tr><td>Sprague Dawley rats</td><td></td><td></td><td>5-6 week old males</td></tr><tr><td>Laptop computer</td><td>Hewlett Packard</td><td></td><td></td></tr><tr><td>Stop Watch</td><td></td><td></td><td></td></tr><tr><td>Forceps</td><td>Fine Science Tools (FST)</td><td></td><td></td></tr><tr><td>Excel</td><td>Microsoft</td><td></td><td></td></tr><tr><td>Prism</td><td>GraphPad</td><td></td><td></td></tr><tr><td>Weighing scale</td><td></td><td></td><td></td></tr><tr><td>Counter</td><td></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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Behavior

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

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

Assessing Forelimb Function after Unilateral Cervical SCI using Novel Tasks: Limb Step-alternation, Postural Instability and Pasta Handling

Cervical spinal cord injury (cSCI) can cause devastating neurological deficits, including impairment or loss of upper limb and hand function. A majority of the spinal cord injuries in humans occur at the cervical levels. Therefore, developing cervical injury models and developing relevant and sensitive behavioral tests is of great importance. Here we describe the use of a newly developed forelimb step-alternation test after cervical spinal cord injury in rats. In addition, we describe two behavioral tests that have not been used after spinal cord injury: a postural instability test (PIT), and a pasta-handling test. All three behavioral tests are highly sensitive to injury and are easy to use. Therefore, we feel that these behavioral tests can be instrumental in investigating therapeutic strategies after cSCI.

Three new behavioral tests (forelimb step-alternation, postural instability test, pasta handling test) for evaluating forelimb function after cervical spinal cord injury in rodents are described.

Cervical spinal cord injury (cSCI) can cause devastating neurological deficits, including impairment or loss of upper limb and hand function. A majority ...

The Vermicelli and Capellini Handling Tests: Simple quantitative measures of dexterous forepaw function in rats and mice

Previous characterizations of rodent eating behavior have revealed that they use coordinated forepaw movements to manipulate food pieces. We have extended upon this work to develop a simple quantitative measure of forepaw dexterity that is sensitive to lateralized impairments and age-dependent changes. Rodents learn skillful forepaw and digit movements to manage thin pasta pieces, which they eagerly consume. We have previously described methods for quantifying vermicelli handling in rats and showed that the measures are very sensitive to forelimb impairments resulting from unilateral ischemic lesions, middle cerebral artery occlusions and unilateral striatal dopamine depletion [Allred, R.P., Adkins, D.L., Woodlee, M.T., Husbands, L.C., Maldonado M.A., Kane, J.R., Schallert, T. &amp; Jones, T.A. The Vermicelli Handling Test: a simple quantitative measure of dexterous forepaw function in rats. J. Neurosci. Methods 170, 229-244 (2008)]. Here we present a more detailed protocol for this test in rats and compare it with a newly developed version for mice, the Capellini Handling Test. Rats and mice are videotaped while handling short lengths of uncooked vermicelli or capellini pasta, respectively, with a camera positioned to optimize the view of paw movements. Slow motion video playback allows for the identification of forepaw adjustments, defined as any distinct removal and replacement of the paw, or of any number of digits, on the pasta piece after eating commences. Forepaw adjustments per piece are averaged over trials per each testing session. Repeated testing permits sensitive quantitative analysis of changes in forepaw dexterity over time. Protocols for pre-testing habituation and handling practice, as well as procedures for characterizing atypical handling patterns, are described. Because rats and mice perform the pasta handling tests slightly differently, species-specific differences in administration and scoring of these tests are highlighted. All animal use was in accordance with protocols approved by the University of Texas at Austin Animal Care and Use Committee.

The Vermicelli and Capellini Handling Tests of forepaw dexterity take advantage of the natural inclination of rodents to manipulate food items using skillful forepaw and digit movements. Animals are videotaped while handling short strands of uncooked dry pasta. Slow motion video playback allows for the quantification of forepaw adjustments.

Previous characterizations of rodent eating behavior have revealed that they use coordinated forepaw movements to manipulate food pieces. We have extended ...

Neuroscience

Study Motor Skill Learning by Single-pellet Reaching Tasks in Mice

Reaching for and retrieving objects require precise and coordinated motor movements in the forelimb. When mice are repeatedly trained to grasp and retrieve food rewards positioned at a specific location, their motor performance (defined as accuracy and speed) improves progressively over time, and plateaus after persistent training. Once such reaching skill is mastered, its further maintenance does not require constant practice. Here we introduce a single-pellet reaching task to study the acquisition and maintenance of skilled forelimb movements in mice. In this video, we first describe the behaviors of mice that are commonly encountered in this learning and memory paradigm, and then discuss how to categorize these behaviors and quantify the observed results. Combined with mouse genetics, this paradigm can be utilized as a behavioral platform to explore the anatomical underpinnings, physiological properties, and molecular mechanisms of learning and memory.

Persistent practice improves the precision of coordinated movements.&#160;Here we introduce a single-pellet reaching task, which is designed to assess the learning and memory of forelimb skill in mice.&#160;

Reaching for and retrieving objects require precise and coordinated motor movements in the forelimb. When mice are repeatedly trained to grasp and ...

Investigating Motor Skill Learning Processes with a Robotic Manipulandum

Skilled reaching tasks are commonly used in studies of motor skill learning and motor function under healthy and pathological conditions, but can be time-intensive and ambiguous to quantify beyond simple success rates. Here, we describe the training procedure for reach-and-pull tasks with ETH Pattus, a robotic platform for automated forelimb reaching training that records pulling and hand rotation movements in rats. Kinematic quantification of the performed pulling attempts reveals the presence of distinct temporal profiles of movement parameters such as pulling velocity, spatial variability of the pulling trajectory, deviation from midline, as well as pulling success. We show how minor adjustments in the training paradigm result in alterations in these parameters, revealing their relation to task difficulty, general motor function or skilled task execution. Combined with electrophysiological, pharmacological and optogenetic techniques, this paradigm can be used to explore the mechanisms underlying motor learning and memory formation, as well as loss and recovery of function (e.g. after stroke).

A paradigm is presented for training and analysis of an automated skilled reaching task in rats. Analysis of pulling attempts reveals distinct subprocesses of motor learning.

Skilled reaching tasks are commonly used in studies of motor skill learning and motor function under healthy and pathological conditions, but can be ...

The Structure of Skilled Forelimb Reaching in the Rat: A Movement Rating Scale

Skilled reaching for food is an evolutionary ancient act and is displayed by many animal species, including those in the sister clades of rodents and primates. The video describes a test situation that allows filming of repeated acts of reaching for food by the rat that has been mildly food deprived. A rat is trained to reach through a slot in a holding box for food pellet that it grasps and then places in its mouth for eating. Reaching is accomplished in the main by proximally driven movements of the limb but distal limb movements are used for pronating the paw, grasping the food, and releasing the food into the mouth. Each reach is divided into at least 10 movements of the forelimb and the reaching act is facilitated by postural adjustments. Each of the movements is described and examples of the movements are given from a number of viewing perspectives. By rating each movement element on a 3-point scale, the reach can be quantified. A number of studies have demonstrated that the movement elements are altered by motor system damage, including damage to the motor cortex, basal ganglia, brainstem, and spinal cord. The movements are also altered in neurological conditions that can be modeled in the rat, including Parkinson's disease and Huntington's disease. Thus, the rating scale is useful for quantifying motor impairments and the effectiveness of neural restoration and rehabilitation. Because the reaching act for the rat is very similar to that displayed by humans and nonhuman primates, the scale can be used for comparative purposes. from a number of viewing perspectives. By rating each movement element on a 3-point scale, the reach can be quantified. A number of studies have demonstrated that the movement elements are altered by motor system damage, including damage to the motor cortex, basal ganglia, brainstem, and spinal cord. The movements are also altered in neurological conditions that can be modeled in the rat, including Parkinson's disease and Huntington's disease. Thus, the rating scale is useful for quantifying motor impairments and the effectiveness of neural restoration and rehabilitation.

Experiments on animals were performed in accordance with the guidelines and regulations set forth by the University of Lethbridge Animal Care Committee in accordance with the regulations of the Canadian Council on Animal Care.

The skilled reaching scale divides the movement by a forelimb in a reach for food act into composite elements each of which are evaluated with a three-point scale. The rating scale is described for a normal rat and can be applied toward evaluating neurological motor disorders.

Skilled reaching for food is an evolutionary ancient act and is displayed by many animal species, including those in the sister clades of rodents and ...

Biology

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 ...

Automated Rat Single-Pellet Reaching with 3-Dimensional Reconstruction of Paw and Digit Trajectories

Rodent skilled reaching is commonly used to study dexterous skills, but requires significant time and effort to implement the task and analyze the behavior. Several automated versions of skilled reaching have been developed recently. Here, we describe a version that automatically presents pellets to rats while recording high-definition video from multiple angles at high frame rates (300 fps). The paw and individual digits are tracked with DeepLabCut, a machine learning algorithm for markerless pose estimation. This system can also be synchronized with physiological recordings, or be used to trigger physiologic interventions (e.g., electrical or optical stimulation).

Rodent skilled reaching is commonly used to study dexterous skills, but requires significant time and effort to implement the task and analyze the behavior. We describe an automated version of skilled reaching with motion tracking and three-dimensional reconstruction of reach trajectories.

Rodent skilled reaching is commonly used to study dexterous skills, but requires significant time and effort to implement the task and analyze the ...

In Vivo Wireless Optogenetic Control of Skilled Motor Behavior

Fine motor skills are essential in everyday life and can be compromised in several nervous system disorders. The acquisition and performance of these tasks require sensory-motor integration and involve precise control of bilateral brain circuits. Implementing unimanual behavioral paradigms in animal models will improve the understanding of the contribution of brain structures, like the striatum, to complex motor behavior as it allows manipulation and recording of neural activity of specific nuclei in control conditions and disease during the performance of the task. 
Since its creation, optogenetics has been a dominant tool for interrogating the brain by enabling selective and targeted activation or inhibition of neuronal populations. The combination of optogenetics with behavioral assays sheds light on the underlying mechanisms of specific brain functions. Wireless head-mounted systems with miniaturized light-emitting diodes (LEDs) allow remote optogenetic control in an entirely free-moving animal. This avoids the limitations of a wired system being less restrictive for animals' behavior without compromising light emission efficiency. The current protocol combines a wireless optogenetics approach with high-speed videography in a unimanual dexterity task to dissect the contribution of specific neuronal populations to fine motor behavior.

In Vivo Wireless Optogenetic Control of Skilled Motor Behavior

The present protocol describes how to use wireless optogenetics combined with high-speed videography in a single pellet reach-to-grasp task to characterize the neural circuits involved in the performance of skilled motor behavior in freely moving mice.

Fine motor skills are essential in everyday life and can be compromised in several nervous system disorders. The acquisition and performance of these ...

Assessing Dexterity with Reaching Tasks

Reaching tasks are employed in behavioral neuroscience to investigate motor learning and forelimb dexterity. Much like human hands, rodents have dexterous forepaws, which are necessary for executing coordinated and precise motor movements. Experimenters may utilize food rewards to train rodents to reach and for testing their reaching abilities. These tasks help behavioral neuroscientist in understanding how CNS injuries, such as a stroke, may impair reaching ability and dexterity in humans.
This video begins by discussing the principles and neurobiology of forelimb use in rodents, and then explains a protocol on how to conduct reaching experiments using different types of food rewards. Applications section reviews studies that involve reaching and food handling in animal models of CNS injury.

Reaching Tasks: Accessing Motor Learning and Dexterity

Reaching tasks are employed in behavioral neuroscience to investigate motor learning and forelimb dexterity. Much like human hands, rodents have dexterous ...

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

Summary

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Chapters in this video

Assessing Forelimb Function after Unilateral Cervical SCI using Novel Tasks: Limb Step-alternation, Postural Instability and Pasta Handling

The Vermicelli and Capellini Handling Tests: Simple quantitative measures of dexterous forepaw function in rats and mice

Study Motor Skill Learning by Single-pellet Reaching Tasks in Mice

Investigating Motor Skill Learning Processes with a Robotic Manipulandum

The Structure of Skilled Forelimb Reaching in the Rat: A Movement Rating Scale

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

Evaluating Skilled Prehension in Mice Using an Auto-Trainer

Automated Rat Single-Pellet Reaching with 3-Dimensional Reconstruction of Paw and Digit Trajectories

In Vivo Wireless Optogenetic Control of Skilled Motor Behavior

Assessing Dexterity with Reaching Tasks