Este trabalho foi financiado por doações do National Science Foundation suíço (Grant 31003A-149.315-1 para MES e Grant IZK0Z3-150809 a AZ), a AZ Fundação Heidi Demetriades, para MES, o Conselho Europeu de Investigação (&#39;Nogorise&#39;) eo Christopher e Dana Reeve Foundation (CDRF).

Todos os experimentos foram realizados de acordo com as orientações do Serviço Veterinário do cantão Zurique, Suíça. 1. Handling Animal e Habituação <ol><li> Manejo dos animais Nota: 5 dias antes do início da experiência, efectuar o passo 1.1.1 diária. <ol><li> Para experimentos comportamentais, acostumar os animais para o experimentador. Já diária manipulação sessões com duração de 10-15 minutos por animal. Limpe a caixa após a sessão de cada animal. <ol><li> Inicialmente, coloque a mão do experimentador em uma gaiola permitindo que o animal para explorar e cheirar a tornar-se familiarizado com o experimentador. </li><li> Em seguida, levante com cuidado o animal com a mão do experimentador de forma segura, segurando o corpo do rato entre as patas traseiras front e que permitam uma maior familiarização. </li></ol></li><li> Pesar cada animal diariamente para obter um peso corporal de base antes de privação de alimento. </li></ol&gt; </li><li> Aparelho de Habituação e Familiarização Food <ol><li> Pesar cada animal diariamente para obter um peso corporal de base antes de privação de alimento. </li><li> Iniciar a comida privando ratos 3 dias antes do início da pré-formação com uma dieta padrão de laboratório. Submeter ratos 0,05 g de alimento por 1 g de peso corporal por dia (por exemplo, um rato pesando 200 g, começar com 10 g de alimento). Certifique-se de peso corporal a não diminuir mais de 10% por dia de peso corporal por dia através da monitorização. <ol><li> Se vários animais são mantidos em uma gaiola, ratos dominantes podem comer mais do que as menos dominantes. No caso de o peso corporal de um animal diminui, alimentar o animal em separado, em vez de alimentação em grupo. Dê ad libitum água. </li></ol></li><li> Para familiarizar o rato com o aparelho de agarrar, coloque o animal na caixa de treinamento (Figura 1). Já pelotas de açúcar colocados na caixa de formação na proximidade da abertura de fenda para familiarizar o animal com os peletes de alimento. Execute esta stEP 10-15 min por dia durante 3 dias. </li></ol></li></ol> 2. Pré-treinamento e habilidade Aprendizagem Motora <ol><li> Pré-treinamento <ol><li> Um dia depois de familiarização, coloque o animal na caixa de treino e coloque a pastilha de perto para a abertura de fenda para que ele possa ser alcançado pela língua do animal. Excluir animais que recuperam pellets com sua pata dianteira durante a pré-formação Nota: Nesta fase, a recuperação da pelota com a língua é crucial e geralmente o método de escolha do animal. Pelotas deve ser em nenhum caso apreendido com o membro anterior até o primeiro dia de aprendizado de habilidades motoras para permitir um acompanhamento adequado da tarefa atingindo aprendido. Recuperação Pellet com o membro anterior durante a pré-formação é um critério de exclusão e é na maioria dos casos não observados. </li><li> Ensina o rato ou a correr para a parte de trás da jaula e voltar para a abertura de fenda ou voltar e virar em torno do seu próprio eixo, a fim de receber a próxima pelete com comidaa lingua. Permitir que o tempo para o animal para explorar a gaiola, executar a parte de trás e voltar para a abertura de fenda. Se o animal não executar corretamente a tarefa, use uma pinça para tocar suavemente na parte de trás final da gaiola e chamar a atenção do animal. Uma vez que o animal é na parte traseira, bater suavemente em frente da gaiola para guiar o animal para a abertura de fenda. Nota: Uma vez que o animal atinge um valor padrão definido (por exemplo, 50 recuperações de pelotização de sucesso com a língua em menos de 15 min), o animal se qualifica para o estágio de aprendizagem de habilidades motoras. No dia 1 e 2 de pré-treinamento, os alunos já pode ser distinguido do não-aprendentes. Não-aprendentes podem ser excluídos do estudo nesta etapa. Isto diminui a probabilidade de ter um elevado número de não-formandos durante o passo de aprendizagem motora (2.2). </li><li> Durante a pré-treinamento, comida privar ratos em uma dieta padrão de laboratório. Dê ad libitum água. Monitor de peso corporal por dia durante todo o estudo. FazNão use o mesmo espaço para treinar ratos machos e fêmeas. Garantir um ambiente calmo e livre de ruído para o animal. </li></ol></li><li> Determinação de Preferência da pata e habilidade Aprendizagem Motora <ol><li> Durante a primeira sessão de aprendizagem de habilidades motoras, substitua a lâmina na frente da janela com um post. Coloque o açúcar pellet cerca de 1,5 cm de distância da janela sobre o post para que o animal não pode alcançar a pelota com a língua, mas apenas recuperá-lo por um membro anterior preciso alcançar e agarrar movimento. <ol><li> Para impor a recuperação pellet pelo membro anterior, use uma pinça para trazer suavemente o sedimento perto da boca do animal e retirar o sedimento enquanto o animal tenta consumo com a língua. Realizar esta tarefa repetidamente até que o animal se estende a pata dianteira e agarra uma pelota. </li></ol></li><li> Coloque o posto central para a abertura da janela. Para determinar a preferência pata, observar cuidadosamente as 10 primeiros ensaios no dia formação 1. Mais de 70% da reaching tentativas (ou seja, 7 out of 10) tem que ser executado com o mesmo membro anterior. Se isso não for alcançado, continue com outra rodada de 10 tentativas até que o limite de 70% seja alcançado. </li><li> Após a determinação preferência pata, mudar o posto para o membro anterior preferida e alinhar central para a borda da abertura da janela. Alinhamento da pata preferidos significa o contrário de pós é deslocado para o respectivo pata para permitir um ângulo óptimo para alcançar (Figura 1B, C). </li><li> Classificar um julgamento, definido como um novo pellet apresentado ao animal, tão bem sucedido (alcançar, agarrar, recuperar e comer o sedimento), queda (chegar, segure e perder sedimento durante a recuperação) ou não (pellet bater no poste). Anote todas as provas em sua folha e analisar os dados após o experimento. </li><li> Realizar uma sessão diária que consiste de um número definido de ensaios (por exemplo, 150) ou um tempo máximo (por exemplo, 1 hora) para cada animal. </li><li> Investigar precisão e ajuste finodo movimento por meio de análise primeira tentativa. A primeira tentativa é definida por agarrando do sedimento em um único movimento monolítico sem interrupção, hesitação ou repetição de componentes de movimento individuais. Observar cuidadosamente cada aperto pelo rato. <ol><li> Se o rato hesita ou se retrai durante um alcance ou tentativas de várias tentativas de compreender corretamente o pellet, observe o respectivo julgamento como sucesso, mas não primeira tentativa. Se o animal agarra com sucesso o sedimento em um único alcance monolítico, anote o respectivo julgamento como primeira tentativa bem sucedida em uma coluna separada em sua folha. </li></ol></li><li> Durante o aprendizado de habilidades motoras, comida privar ratos em uma dieta padrão de laboratório. Dê ad libitum água. Monitor de peso corporal por dia durante todo o estudo. </li></ol></li></ol>

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The authors have nothing to disclose

O paradigma mostrado neste estudo é adaptado de Buitrago et al 18 e difere do sedimento clássica único atingindo paradigma 17 principalmente em dois aspectos.: Em primeiro lugar, estudar melhoria dentro de sessões permite a análise da tarefa aprendida dentro de um único dia, o que pode fornecer um nível diferente de informação, tais como investigação da componente de aprendizagem rápido em comparação com a componente de aprendizagem lento represen...

Controle de movimento é uma função essencial do sistema nervoso central (SNC). Motricity é a principal saída mensurável da função do SNC ea principal possibilidade para que os indivíduos interagem com o mundo externo. Compreender os princípios da função motora e os mecanismos que estão na base da aprendizagem de uma tarefa motora é atualmente um dos grandes desafios da neurociência. As alterações morfológicas, fisiológicas e moleculares foram encontrados na aquisição de uma tarefa motora nova. Por exemplo, a forma eo número de sinapses mudar em resposta ao treinamento motor hábil 1-5, e foram observadas alterações funcionais da maquinaria sináptica após aprendizagem motora. As respostas sinápticas foram maiores nas ligações da região-representando membro anterior do córtex motor treinados em comparação com o hemisfério não treinado do mesmo animal ou para respostas dos animais não treinados 6,7. Observações electrofisiológicas também sugerem que a potenciação de longo prazo (LTP) e longodepressão -termo (LTD) como mecanismos de ter lugar durante o aprendizado de uma nova habilidade motora, e que a faixa de operação sináptica, que é definida entre as fronteiras limitantes de LTP e saturação LTD, é modificado 8. Além disso, demonstrou-se que os marcadores de actividade e da plasticidade que promovem a moléculas tais como c-fos, GAP-43, ou BDNF, mas também moléculas que inibem a plasticidade, tais como papéis reguladores Nogo-A exibição de plasticidade neuronal relacionada com a aprendizagem 9-16. Estes avanços no sentido de uma melhor compreensão dos mecanismos subjacentes à aprendizagem motora só poderia ser alcançado com o uso de paradigmas comportamentais que permitem o controle preciso da aquisição de uma nova habilidade motora, por exemplo, hábil membro anterior de longo alcance. Apenas uma tarefa comportamental bem estruturado permite monitorar e capturar as alterações correlativas que ocorrem ao tomar conhecimento e execução da respectiva tarefa. Aqui nós demonstrar visualmente uma versão modificada do membro anterior qualificadossingle-pellet atingindo tarefa em ratos adaptados de Buitrago et al. 17 O paradigma apresentado permite a análise da aquisição movimento dentro de uma sessão diária de treinamento (dentro de sessões), representando o componente de aprendizagem rápida e aquisição primária, bem como a aprendizagem motora hábil ao longo de várias sessões (entre as sessões) que representa a componente de aprendizagem lenta e manutenção da tarefa aprendida 18. É importante ressaltar que este paradigma comportamental aumenta o grau de dificuldade e complexidade da tarefa de habilidade motora devido a duas características: primeiro, os ratos são treinados para virar seu eixo após cada alcance e, portanto, para realinhar seu corpo antes da próxima alcance pellet e renovar a orientação do corpo, impedindo execução do movimento constante a partir do mesmo ângulo. Em segundo lugar, os sedimentos são recuperados a partir de um poste vertical colocado em frente da gaiola. Devido ao pequeno diâmetro do post, pelotas pode facilmente ser expulso exigindo um aperto preciso para a recuperação bem sucedida e pREVENÇÃO simples puxar da pelota para o animal. Tal teste comportamental complexo permite uma percepção mais profunda sobre os mecanismos subjacentes à aprendizagem motora. Comparado com os ratinhos, os ratos são superiores no desempenho de tarefas comportamentais complexas e portanto mais adequado para paradigmas complexos, tal como apresentado no presente estudo. Considerando as crescentes possibilidades genéticas disponível para ratos 19,20, a combinação de métodos de ensaio comportamental precisos e bem controlados com manipulações genéticas, imagiologia e técnicas fisiológicas representa uma caixa de ferramentas poderosas para compreender melhor a base neurobiológica da aprendizagem motora e memória.

<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.

Aquisição de habilidades motoras sucesso só é alcançado através da prática consistente. Apesar cuidadosa consideração de todos os aspectos, alguns ratos não saiba a tarefa (Figura 2). Estes &quot;não-aprendentes ou falta de motivação, resultando em poucas ou inexistentes as tentativas de recuperação de pellet a partir do início da experiência ou geralmente perdem o interesse em alcançar para as pelotas que levam à continuamente tentativas fracassadas. Por outro lado, alguns animais ap...

Watch this Scientific Journal Video about Acquisition of a High-precision Skilled Forelimb Reaching Task in Rats at JoVE.com

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.

Aquisição de um de alta precisão Skilled Membro Anterior Alcançar Task em Ratos

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

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Universidad de Cartagena UDEC

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

Vídeo: 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.

Avaliação da Função Membro Anterior após Unilateral Cervical SCI usando tarefas Novel: Membro Passo alternância, instabilidade postural e Pasta Manipulação

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

Comportamento

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.

O Vermicelli e Testes Handling Capellini: Simple medidas quantitativas da função forepaw dexterous em ratos e camundongos

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

Neurociência

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;

Estudo Motor Habilidade Aprendizagem por Single-pelota Tarefas atingindo em Ratos

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.

Investigação dos processos de aprendizagem motora habilidade com uma 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 ...

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.

A Estrutura do Membro Anterior Skilled Chegar no Rato: A Escala de Avaliação Movimento

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 ...

Biologia

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.

A tarefa de supinação de botão: Um método semi-automático para avaliar a função do Forelimb em ratos

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.

Avaliando a Prehension qualificada em camundongos usando um instrutor automático

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.

Automatizado Rat single-pellet atingindo com 3-dimensional reconstrução de pata e dígitos trajetórias

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.

In vivo Controle Optogenético Sem Fio do Comportamento Motor Qualificado

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

Avaliando a destreza com tarefas de alcance

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