Este trabajo fue financiado por becas de la Fundación Nacional de Ciencia de Suiza (Grant 31003A-149315-1 de MES y de Grant IZK0Z3-150809 a AZ), a la Fundación AZ Heidi Demetriades, al MES Consejo Europeo de Investigación (&#39;Nogorise&#39;) y el Christopher y Dana Reeve Fundación (CDRF).

Todos los experimentos se realizaron de acuerdo con las directrices de la Oficina Veterinaria del Cantón de Zurich, Suiza. 1. Animal Manipulación y habituación <ol><li> Manejo Animal Nota: 5 días antes del comienzo del experimento, realizar el paso 1.1.1 diaria. <ol><li> Para los experimentos de comportamiento, acostumbrar a los animales para el experimentador. Han manejo diario de sesiones que duran 10-15 minutos por animal. Limpie la caja después de la sesión de cada animal. <ol><li> Inicialmente, coloque la mano del experimentador en una jaula que permite al animal para explorar y oler a familiarizarse con el experimentador. </li><li> A continuación, levante suavemente el animal con la mano del experimentador de una manera segura sujetando el cuerpo de la rata entre las patas delanteros y traseros que permiten mayor familiarización. </li></ol></li><li> Pesar cada animal al día para obtener un peso corporal basal antes de la privación de alimentos. </li></ol&gt; </li><li> Aparato habituación y familiarización de Alimentos <ol><li> Pesar cada animal al día para obtener un peso corporal basal antes de la privación de alimentos. </li><li> Iniciar alimentos privando ratas 3 días anteriores al inicio del pre-entrenamiento con una dieta estándar de laboratorio. Dé ratas 0,05 g de alimento por 1 g de peso corporal por día (por ejemplo, una rata de pesaje 200 g, comenzar con 10 g de alimento). Asegúrese de peso corporal a no disminuir más de 10% por día mediante el control de peso corporal al día. <ol><li> Si varios animales se llevan a cabo en una jaula, ratas dominantes pueden comer más que las menos dominantes. En caso de que el peso del cuerpo de una disminución de los animales, alimentar a los animales por separado en lugar de alimentación de grupos. Danos agua ad libitum. </li></ol></li><li> Dar a conocer a la rata con el aparato de captación, coloque el animal en el cuadro de la formación (Figura 1). Tener gránulos de azúcar colocados en el cuadro de la formación en la proximidad de la abertura de ranura para familiarizar al animal con las bolitas de comida. Realice este step 10-15 minutos al día durante 3 días. </li></ol></li></ol> 2. Pre-entrenamiento y aprendizaje de habilidades motoras <ol><li> Pre-entrenamiento <ol><li> Un día después de la familiarización, coloque el animal en el cuadro de la formación y colocar la pastilla de cerca a la abertura de ranura por lo que se puede llegar por la lengua del animal. Excluir los animales que recuperan pellets con su extremidad anterior durante la pre-entrenamiento Nota: En esta etapa, la recuperación de pellets con la lengua es crucial y por lo general el método del animal de elección. Los pellets deben ser en ningún caso captado con la extremidad anterior hasta el primer día de aprendizaje de habilidades motoras para permitir un seguimiento adecuado de la tarea de llegar a aprender. La recuperación de pellets con la extremidad anterior durante la pre-formación es un criterio de exclusión y se encuentra en la mayoría de los casos no observados. </li><li> Enseñe a la rata ya sea correr hacia la parte trasera de la caja y volver a la abertura de ranura o un paso atrás y girar sobre su propio eje con el fin de recibir la siguiente bola de comida conla lengua. Dé tiempo para que el animal pueda explorar la jaula, correr hacia atrás y volver a la abertura de ranura. Si el animal no se ejecuta correctamente la tarea, utilice una pinza para golpear suavemente en la parte trasera final de la jaula y atraer la atención del animal. Una vez que el animal es en la parte trasera, golpee suavemente en la parte delantera jaula para guiar el animal a la abertura de ranura. Nota: Una vez que el animal alcanza un valor estándar definido (por ejemplo, 50 recuperaciones de pellets de éxito con la lengua en menos de 15 min), el animal califica para la etapa de aprendizaje de habilidades motoras. El día 1 y 2 de la pre-formación, los alumnos ya pueden distinguirse de los no estudiantes. Los no principiantes pueden ser excluidos del estudio en este paso. Esto disminuye la probabilidad de tener un alto número de no estudiantes durante la etapa de aprendizaje motor (2.2). </li><li> Durante la pre-entrenamiento, comida privar ratas con una dieta estándar de laboratorio. Danos agua ad libitum. Vigilar el peso corporal al día durante todo el estudio. HacerNo utilice misma habitación para entrenar ratas machos y hembras. Asegurar un ambiente tranquilo y libre de ruidos para el animal. </li></ol></li><li> Determinación de Preferencia de la pata y el aprendizaje de habilidades motoras <ol><li> Durante el primer período de sesiones de aprendizaje de habilidades motoras, reemplace la diapositiva en frente de la ventana con un mensaje. Coloque la pastilla de azúcar alrededor de 1,5 cm de distancia de la ventana en el post para que el animal no puede llegar a la pastilla con la lengua, pero sólo recuperarlo por un miembro anterior preciso alcanzar y agarrar el movimiento. <ol><li> Para hacer cumplir la recuperación de pellet por la extremidad anterior, utilizar un fórceps para llevar suavemente el sedimento cerca de la boca del animal y retraiga el sedimento mientras el animal intenta consumo con la lengua. Llevar a cabo esta tarea de forma repetitiva hasta que el animal se extiende la extremidad anterior y agarra un pellet. </li></ol></li><li> Coloque el poste central de la abertura de la ventana. Para determinar la preferencia de la pata, observar cuidadosamente los primeros 10 ensayos en la jornada de formación 1. Más del 70% de la reacintentos hing (es decir, 7 de cada 10) tienen que ser ejecutados con la misma extremidad anterior. Si esto no se logra, continúe con otra ronda de 10 ensayos hasta que se alcanza el umbral del 70%. </li><li> Después de la determinación de preferencias de la pata, cambiar el mensaje hacia la extremidad anterior preferido y alinear central en el borde de la abertura de la ventana. La alineación de la pata preferido significa el poste se desplaza en contra de la respectiva pata para permitir un ángulo óptimo para llegar a (Figura 1B, C). </li><li> Clasifique un juicio, que se define como una nueva pastilla presentado al animal, el mismo éxito (alcanzar, agarrar, recuperar y comer la pastilla), gota (alcanzar, agarrar y perder pellet durante la recuperación) o no (knock pellet en el poste). Tome nota de cada prueba en su hoja y analizar los datos después del experimento. </li><li> Realice una sesión diaria que consiste en un número definido de ensayos (por ejemplo, 150) o un tiempo máximo (por ejemplo, 1 hr) para cada animal. </li><li> Investigar la precisión y la puesta a puntodel movimiento usando primer análisis intento. Un primer intento se define por el agarre del pellet en un solo movimiento monolítico sin interrupción, vacilación o repetición de componentes de movimiento individuales. Observe cuidadosamente cada uno agarre por la rata. <ol><li> Si la rata vacila o se retrae durante un alcance o intente varios ensayos para comprender correctamente la pastilla, tenga en cuenta el juicio respectivo como el éxito, pero no el primer intento. Si el animal capta con éxito el precipitado en un solo alcance monolítico, anotar el juicio respectivo tan exitoso primer intento en una columna separada en su hoja. </li></ol></li><li> Durante el aprendizaje de habilidades motoras, comida privar ratas con una dieta estándar de laboratorio. Danos agua ad libitum. Vigilar el peso corporal al día durante todo el estudio. </li></ol></li></ol>

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The authors have nothing to disclose

El paradigma se muestra en este estudio es una adaptación de Buitrago et al 18 y difiere de la pastilla única clásica alcanzar paradigma 17 principalmente en dos aspectos.: En primer lugar, el estudio de mejora dentro de la sesión permite el análisis de la tarea aprendida dentro de un solo día, que puede proporcionar un nivel diferente de la información, tales como la investigación del componente de aprendizaje rápido en comparación con el componente ...

Control de movimiento es una función básica del sistema nervioso central (SNC). Motricity es la principal salida mensurable de la función del SNC y la posibilidad principal para que las personas interactúan con el mundo externo. La comprensión de los principios de la función motora y los mecanismos que subyacen en el aprendizaje de una tarea motora es actualmente uno de los grandes retos de la neurociencia. No se encontraron cambios morfológicos, fisiológicos y moleculares en la adquisición de una nueva tarea motora. Por ejemplo, la forma y el número de sinapsis cambian en respuesta al entrenamiento motor experto 1-5, y no se observaron cambios funcionales de la maquinaria sináptica después de aprendizaje motor. Las respuestas sinápticas fueron mayores en las conexiones de la región de la extremidad anterior-representación de de la corteza motora entrenado en comparación con el hemisferio no entrenado del mismo animal o a las respuestas procedentes de animales no entrenados 6,7. Observaciones electrofisiológicas también sugieren que la potenciación a largo plazo (LTP) y largo-término depresión (LTD) como mecanismos tienen lugar durante el aprendizaje de una nueva habilidad motora, y que el rango de operación sináptica, que se define entre las fronteras limitantes de LTP y la saturación LTD, se modifica 8. Además, se ha demostrado que los marcadores de actividad y plasticidad que promueven moléculas tales como c-fos, GAP-43, o BDNF, sino también de plasticidad moléculas inhibidoras tales como Nogo-A de visualización de funciones de regulación para el aprendizaje relacionadas con la plasticidad neuronal-9-16. Estos avances hacia una mejor comprensión de los mecanismos subyacentes de aprendizaje motor sólo podrían lograrse con el uso de paradigmas de comportamiento que permiten un control preciso de la adquisición de una nueva habilidad motora, por ejemplo, llegar a la extremidad anterior cualificados. Sólo una tarea conductual bien estructurada permite monitorizar y capturar los cambios correlativos que se producen en el aprendizaje y la ejecución de la tarea en cuestión. Aquí se demuestra visualmente una versión modificada de la extremidad anterior expertouna sola pastilla llegar tarea en ratas adaptados de Buitrago et al. 17 El paradigma presentado permite el análisis de la adquisición de movimiento dentro de una sesión de entrenamiento al día (dentro del período de sesiones), que representa el componente de rápido aprendizaje y adquisición de primaria, así como el aprendizaje motor calificado en varias sesiones (entre sesiones) que representa el componente de aprendizaje lento y mantenimiento de la tarea aprendida 18. Es importante destacar que este paradigma de comportamiento aumenta el grado de dificultad y complejidad de la tarea de habilidades motoras debido a dos características: en primer lugar, las ratas están capacitados para dar vuelta alrededor de su eje después de cada agarre y por lo tanto para realinear su cuerpo antes de la siguiente alcance de pellets y renovar la orientación del cuerpo, impidiendo la ejecución movimiento constante desde el mismo ángulo. En segundo lugar, los gránulos se recuperan de un poste vertical colocado delante de la jaula. Debido al pequeño diámetro del puesto, los pellets pueden ser fácilmente iniciaron requiere un conocimiento preciso para la recuperación y la p exitosareventing sencilla tirando de la pastilla hacia el animal. Estas pruebas de comportamiento complejo permite una visión más profunda de los mecanismos subyacentes aprendizaje motor. En comparación con los ratones, las ratas son superiores en su desempeño de las tareas de comportamiento complejas y por lo tanto más adecuado para paradigmas complejos tal como se presenta en este estudio. Teniendo en cuenta las crecientes posibilidades genéticas disponibles para ratas 19,20, la combinación de los métodos de prueba de comportamiento precisas y bien controlados con manipulaciones genéticas, imágenes y técnicas fisiológicas representa una potente caja de herramientas para comprender mejor las bases neurobiológicas de aprendizaje motor y la memoria.

<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.

Adquisición de habilidades motoras éxito se logra sólo a través de la práctica constante. A pesar de una cuidadosa consideración de todos los aspectos, algunas ratas no aprenden la tarea (Figura 2). Estos &quot;no educandos ya sea carecen de motivación que resulta en pocas o ausentes los intentos de recuperación de pellets desde el inicio del experimento o generalmente pierden interés en llegar a las pastillas que llevan a fallado continuamente intentos. Por el contrario, algunos animales muest...

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.

Adquisición de una alta precisión Skilled Miembro Anterior Alcanzar Tarea en Ratas

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

Research

JoVE Journal

Behavior

10.2K vistas.  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.

La evaluación de la función Miembro Anterior tras unilateral cervical SCI usando Tareas Novela: Limb Paso alternancia, inestabilidad postural y manipulación Pasta

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

Investigación

Comportamiento

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;

Estudio Motor Habilidad Aprendizaje por Casa de pellets Tareas Llegar en ratones

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

A Novel Method for Assessing Proximal and Distal Forelimb Function in the Rat: the Irvine, Beatties and Bresnahan (IBB) Forelimb Scale

Several experimental models of cervical spinal cord injury (SCI) have been developed recently to assess the consequences of damage to this level of the spinal cord (Pearse et al., 2005, Gensel et al., 2006, Anderson et al., 2009), as the majority of human SCI occur here (Young, 2010; www.sci-info-pages.com). Behavioral deficits include loss of forelimb function due to damage to the white matter affecting both descending motor and ascending sensory systems, and to the gray matter containing the segmental circuitry for processing sensory input and motor output for the forelimb. Additionally, a key priority for human patients with cervical SCI is restoration of hand/arm function (Anderson, 2004). Thus, outcome measures that assess both proximal and distal forelimb function are needed. Although there are several behavioral assays that are sensitive to different aspects of forelimb recovery in experimental models of cervical SCI (Girgis et al., 2007, Gensel et al., 2006, Ballerman et al., 2001, Metz and Whishaw, 2000, Bertelli and Mira, 1993, Montoya et al., 1991, Whishaw and Pellis, 1990), few techniques provide detailed information on the recovery of fine motor control and digit movement.
The current measurement technique, the Irvine, Beatties and Bresnahan forelimb scale (IBB), can detect recovery of both proximal and distal forelimb function including digit movements during a naturally occurring behavior that does not require extensive training or deprivation to enhance motivation. The IBB was generated by observing recovery after a unilateral C6 SCI, and involves video recording of animals eating two differently shaped cereals (spherical and doughnut) of a consistent size. These videos were then used to assess features of forelimb use, such as joint position, object support, digit movement and grasping technique.
The IBB, like other forelimb behavioral tasks, shows a consistent pattern of recovery that is sensitive to injury severity. Furthermore, the IBB scale could be used to assess recovery following other types of injury that impact normal forelimb function.

A Novel Method for Assessing Proximal and Distal Forelimb Function in the Rat: the Irvine, Beatties and Bresnahan IBB Forelimb Scale

Here we will describe a rodent behavioral assay that can detect recovery of both proximal and distal forelimb function including digit movements during a naturally occurring behavior that does not require extensive training or deprivation to enhance motivation.

Un nuevo método para evaluar la función Miembro Anterior proximal y distal de la rata: el Irvine, Beatties y Bresnahan (IBB) Escala Miembro Anterior

Several experimental models of cervical spinal cord injury (SCI) have been developed recently to assess the consequences of damage to this level of the ...

Neurociencias

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.

La investigación de los procesos de aprendizaje de habilidades motoras con una robótica 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.

La estructura del Miembro Anterior especializada en llegar a la Rata: una escala de calificación del Movimiento

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 ...

Biología

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.

La tarea de supinación de mando: Un método semiautomático para evaluar la función de Forelimb en ratas

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.

Evaluación de la prehensión habilidosa en ratones mediante un auto-entrenador

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.

Rata automatizada de un solo pellet alcanzando la reconstrucción tridimensional de trayectorias de patas y dígitos

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 Control optogenético inalámbrico del comportamiento motor calificado

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

Evaluación de las destrezas al realizar tareas

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