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

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

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

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

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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

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

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

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

El Grupo de Congruencia crossmodal como medio para obtener una medida del comportamiento objetivo de la Guía Caucho mano Illusion Paradigm

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

Investigación

Comportamiento

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

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

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

Un procedimiento para estudiar el efecto de la prolongada restricción de alimentos en heroína Buscando en ratas abstinentes

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

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

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

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

Medición de Fronto-límbico Actividad Usando una Emocional bicho raro de tareas en niños con alto riesgo familiar para la esquizofrenia

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

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

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

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

El 5-Choice Reacción Serial Tiempo de tareas: una tarea de atención y control de los impulsos para Roedores

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

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

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

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

Un procedimiento para observar inducida Contexto-Renovación-pavloviano acondicionado Alcohol comportamiento de búsqueda en ratas

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

The Modified Hole Board - Measuring Behavior, Cognition and Social Interaction in Mice and Rats

This protocol describes the modified hole board (mHB), which combines features from a traditional hole board and open field and is designed to measure multiple dimensions of unconditioned behavior in small laboratory mammals (e.g., mice, rats, tree shrews and small primates). This paradigm is a valuable alternative for the use of a behavioral test battery, since a broad behavioral spectrum of an animal&#8217;s behavioral profile can be investigated in one single test.
The apparatus consists of a box, representing the &#8216;protected&#8217; area, separated from a group compartment. A board, on which small cylinders are staggered in three lines, is placed in the center of the box, representing the &#8216;unprotected&#8217; area of the set-up. The cognitive abilities of the animals can be measured by baiting some cylinders on the board and measuring the working and reference memory. Other unconditioned behavior, such as activity-related-, anxiety-related- and social behavior, can be observed using this paradigm. Behavioral flexibility and the ability to habituate to a novel environment can additionally be observed by subjecting the animals to multiple trials in the mHB, revealing insight into the animals&#8217; adaptive capacities.
Due to testing order effects in a behavioral test battery, na&#239;ve animals should be used for each individual experiment. By testing multiple behavioral dimensions in a single paradigm and thereby circumventing this issue, the number of experimental animals used is reduced. Furthermore, by avoiding social isolation during testing and without the need to food deprive the animals, the mHB represents a behavioral test system, inducing if any, very low amount of stress.

This protocol describes the modified hole board, which is a behavioral test set-up that comprises the characteristics of an open field and a traditional hole board. This set-up enables the differential analysis of unconditioned behavior of small laboratory mammals as well as the analysis of cognitive abilities.

La Junta Agujero Modificado - Medición de Comportamiento, Cognición e interacción social en ratones y ratas

This protocol describes the modified hole board (mHB), which combines features from a traditional hole board and open field and is designed to measure ...

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

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

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

Bola que despide con una velocidad uniformemente variable en una tarea de sincronización de metrónomo

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

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

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

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

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 ...

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

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

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

Una tarea para evaluar el impacto de un socio en la velocidad y precisión del rendimiento del motor en ratas

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