Questo lavoro è stato finanziato da sovvenzioni del Fondo nazionale svizzero (Grant 31003A-149315-1 per MES e di Grant IZK0Z3-150809 di AZ), per AZ il Demetriades Fondazione Heidi, al MES il Consiglio europeo della ricerca (&#39;Nogorise&#39;) e la Christopher e Dana Reeve Foundation (CDRF).

Tutti gli esperimenti sono stati eseguiti in conformità con le linee guida del veterinario del Cantone di Zurigo, Svizzera. 1. Manipolazione di animali e assuefazione <ol><li> Manipolazione di animali Nota: 5 giorni prima dell&#39;inizio dell&#39;esperimento, eseguire il passaggio 1.1.1 giornaliera. <ol><li> Per gli esperimenti comportamentali, abituare gli animali allo sperimentatore. Hanno quotidiana gestione sessioni della durata di 10-15 minuti per ogni animale. Pulire la scatola dopo la sessione di ogni animale. <ol><li> Inizialmente, mettere la mano dello sperimentatore in una gabbia che permette all&#39;animale di esplorare e sentire l&#39;odore di diventare familiarizzato con lo sperimentatore. </li><li> Successivamente, sollevare delicatamente l&#39;animale con la mano dello sperimentatore in modo sicuro afferrando il corpo del topo tra le zampe anteriori e posteriori che consentano una ulteriore familiarizzazione. </li></ol></li><li> Pesare ogni animale al giorno per ottenere un peso corporeo di base prima di privazione di cibo. </li></ol&gt; </li><li> Apparato assuefazione e familiarizzazione alimentare <ol><li> Pesare ogni animale al giorno per ottenere un peso corporeo di base prima di privazione di cibo. </li><li> Inizia cibo privando ratti 3 giorni prima l&#39;inizio del pre-allenamento su una dieta standard di laboratorio. Dare ratti 0,05 g di alimento per 1 g di peso corporeo al giorno (per esempio, un ratto peso 200 g, iniziare con 10 g di cibo). Assicurarsi peso corporeo di non diminuire di più del 10% al giorno monitorando peso corporeo al giorno. <ol><li> Se più animali vengono tenuti in una gabbia, i ratti dominanti possono mangiare più di quelli meno dominanti. Nel caso in cui il peso di un animale diminuisce, nutrire l&#39;animale separatamente invece di gruppo di alimentazione. Dare acqua ad libitum. </li></ol></li><li> Per conoscere il topo con l&#39;apparato di presa, collocare l&#39;animale nella scatola di formazione (Figura 1). Avere pellets zucchero immessi nella casella di formazione in prossimità dell&#39;apertura della fessura per conoscere l&#39;animale con i pellet cibo. Eseguire questo step 10-15 minuti al giorno per 3 giorni. </li></ol></li></ol> 2. Pre-allenamento e abilità di apprendimento Motor <ol><li> Pre-training <ol><li> Un giorno dopo familiarizzazione, posizionare l&#39;animale nella scatola formazione e posizionare il pellet strettamente per l&#39;apertura a fessura in modo che possa essere raggiunto dalla linguetta dell&#39;animale. Escludere gli animali che recuperano pellet con loro arti anteriori durante la pre-formazione Nota: In questa fase, il recupero pellet con la lingua è cruciale e solito metodo dell&#39;animale di scelta. Pellet devono essere in nessun caso colto con la zampa anteriore fino al primo giorno di apprendimento delle capacità motorie per consentire un adeguato monitoraggio del compito di raggiungere imparato. Recupero pellet con la zampa anteriore durante la pre-formazione è un criterio di esclusione e in molti casi non osservate. </li><li> Insegna il ratto o correre sul retro della gabbia e tornare alla apertura a fessura o passo indietro e girare attorno al proprio asse per ricevere il cibo successiva pellet conla lingua. Attendere che l&#39;animale per esplorare la gabbia, eseguire verso la parte posteriore e tornare alla apertura a fessura. Se l&#39;animale non esegue correttamente il compito, utilizzare una pinza a picchiettare delicatamente sul retro fine della gabbia e catturare l&#39;attenzione dell&#39;animale. Una volta che l&#39;animale è sul retro, toccare delicatamente nella parte anteriore della gabbia per guidare l&#39;animale per l&#39;apertura a fessura. Nota: Una volta che l&#39;animale raggiunge un valore standard (ad esempio, 50 recuperi pellet di successo con la lingua in meno di 15 minuti), l&#39;animale si qualifica per la fase di apprendimento delle capacità motorie. Il giorno 1 e 2 di pre-formazione, gli studenti possono già essere distinti da non discenti. Non gli studenti possono essere esclusi dallo studio in questa fase. Questo diminuisce la probabilità di avere un alto numero di non studenti durante la fase di apprendimento del motore (2.2). </li><li> Durante la pre-formazione, cibo privare i ratti su una dieta standard di laboratorio. Dare acqua ad libitum. Monitorare peso corporeo al giorno nel corso dello studio. FareNon usare lo stesso spazio per allenarsi ratti maschi e femmine. Garantire un ambiente tranquillo e privo di rumore per l&#39;animale. </li></ol></li><li> Determinazione del Preference Paw e Skill Learning Motor <ol><li> Durante la prima sessione di apprendimento delle capacità motorie, sostituire la diapositiva davanti alla finestra con un post. Posizionare il pellet zucchero circa 1,5 cm di distanza dalla finestra sul montante in modo che l&#39;animale non può raggiungere il pellet con la lingua ma solo recuperare da un forelimb preciso di raggiungere e afferrare il movimento. <ol><li> Per applicare il recupero pellet dalla zampa anteriore, utilizzare una pinza per portare delicatamente il pellet vicino alla bocca dell&#39;animale e ritirare il pellet mentre l&#39;animale tenta consumo con la lingua. Effettuare questa operazione ripetutamente fino a quando l&#39;animale si allunga la zampa anteriore e afferra un pellet. </li></ol></li><li> Posizionare il montante centrale per l&#39;apertura della finestra. Per determinare la zampa preferenza, osservare con attenzione le prime 10 prove in giornata di formazione 1. Più del 70% del REACtentativi hing (cioè 7 su 10) devono essere eseguiti con la stessa arti anteriori. Se ciò non viene raggiunto, proseguire con un altro ciclo di 10 prove fino al raggiungimento della soglia del 70%. </li><li> Dopo la determinazione della zampa preferenza, spostare la posta verso la zampa anteriore preferito e allineare centrale al confine con l&#39;apertura della finestra. Allineamento paw preferita significa il post viene spostato contrario alla rispettiva zampa per consentire un angolo ottimale per raggiungere (Figura 1B, C). </li><li> Classificare un processo, definito come un nuovo pellet presentato all&#39;animale, come successo (raggiungere, afferrare, recuperare e mangiare il pellet), goccia (raggiungere, afferrare e perdere pellet durante il recupero) o non (battere pellet il palo). Annota ogni prova nel foglio e analizzare i dati dopo l&#39;esperimento. </li><li> Effettuare una sessione giornaliera costituito da un numero definito di prove (ad esempio, 150) o un tempo massimo (ad esempio, 1 ora) per ciascun animale. </li><li> Indagare precisione e messa a puntodel movimento utilizzando prima analisi tentativo. Un primo tentativo è definita afferrando il precipitato in un unico movimento monolitico senza interruzioni, esitazione o ripetizione di singoli componenti del movimento. Osservare attentamente ogni presa dal topo. <ol><li> Se il ratto esita o si ritrae durante una portata o tenta diverse prove di cogliere correttamente la pallina, annotare il relativo processo come il successo, ma non è il primo tentativo. Se l&#39;animale afferra con successo il pellet in un&#39;unica portata monolitico, annotare il relativo processo come successo il primo tentativo in una colonna separata nel foglio. </li></ol></li><li> Durante l&#39;apprendimento delle capacità motorie, cibo privare i ratti su una dieta standard di laboratorio. Dare acqua ad libitum. Monitorare peso corporeo al giorno nel corso dello studio. </li></ol></li></ol>

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The authors have nothing to disclose

Il paradigma mostrato in questo studio è adattato da Buitrago et al 18 e differisce dal classico singolo pellet raggiungendo paradigma 17 principalmente in due aspetti.: In primo luogo, lo studio miglioramento entro sessione permette l&#39;analisi del compito imparato in un solo giorno, che può fornire un diverso livello di informazioni, come ricerca del componente di apprendimento veloce rispetto al componente di apprendimento lenta rappresentati dai valori ...

Controllo del movimento è una funzione fondamentale del sistema nervoso centrale (CNS). Motricità è il principale uscita misurabile della funzione CNS e la principale possibilità per gli individui di interagire con il mondo esterno. Comprendere i principi di funzionamento del motore e dei meccanismi che sono alla base l&#39;apprendimento di un compito motorio è attualmente una delle grandi sfide nel campo delle neuroscienze. Cambiamenti morfologici, fisiologici e molecolari sono stati trovati al momento dell&#39;acquisto di un nuovo compito motorio. Ad esempio, la forma e il numero di sinapsi cambiano in risposta alla formazione qualificata motore 1-5, e cambiamenti funzionali della macchina sinaptica sono stati osservati dopo apprendimento motorio. Risposte sinaptiche erano più elevati nei collegamenti della regione forelimb rappresenta della corteccia motoria addestrato rispetto all&#39;emisfero inesperto dello stesso animale o risposte da animali non allenati 6,7. Osservazioni elettrofisiologiche suggeriscono anche che il potenziamento a lungo termine (LTP) e lungadepressione-termine (LTD) come meccanismi si svolgono durante l&#39;apprendimento di una nuova abilità motoria, e che il raggio d&#39;azione sinaptica, che è definito tra i confini limitanti di LTP e LTD saturazione, viene modificato 8. Inoltre, è stato dimostrato che i marker di attività e plasticità che promuovono molecole come c-fos, GAP-43, o BDNF ma anche plasticità molecole inibitrici, come Nogo-A di visualizzazione ruoli normativi per l&#39;apprendimento correlati neuronali plasticità 9-16. Questi progressi verso una migliore comprensione dei meccanismi alla base dell&#39;apprendimento motorio potrebbe essere raggiunto solo con l&#39;uso di paradigmi comportamentali che permettono un controllo preciso della acquisizione di una nuova capacità motorie, ad esempio, abile zampa anteriore portata. Solo un compito comportamentale ben strutturata permette di monitorare e catturare i cambiamenti che si verificano correlative su apprendimento e l&#39;esecuzione dei rispettivi compiti. Qui mostriamo visivamente una versione modificata del forelimb qualificatisingolo-pellet compito di raggiungere nei ratti adattati da Buitrago et al. 17 Il paradigma presentato consente l&#39;analisi dell&#39;acquisizione movimento all&#39;interno di una sessione di allenamento al giorno (entro sessione) che rappresenta la componente di apprendimento veloce e acquisizione primaria così come l&#39;apprendimento motorio qualificato in diverse sessioni (tra-session) che rappresenta la componente di apprendimento lenta e manutenzione del compito imparato 18. È importante sottolineare che questo paradigma comportamentale aumenta il grado di difficoltà e la complessità del compito abilità motoria a causa di due caratteristiche: in primo luogo, i ratti sono addestrati a girare intorno al proprio asse dopo ogni comprensione e quindi di riallineare il proprio corpo prima del prossimo pellet portata e rinnovare l&#39;orientamento del corpo, impedendo l&#39;esecuzione costante movimento dalla stessa angolazione. In secondo luogo, pellets vengono recuperati da un palo verticale posto davanti alla gabbia. A causa del piccolo diametro del palo, pellet possono essere facilmente dato il via richiede una comprensione precisa per il recupero di successo e preventing semplice trazione del pellet verso l&#39;animale. Tale test comportamentali complesso permette una maggiore comprensione dei meccanismi alla base dell&#39;apprendimento motorio. Rispetto ai topi, ratti sono superiori nella loro esecuzione dei compiti comportamentali complessi e quindi più adatto per paradigmi complessi come presentato in questo studio. Considerando le crescenti possibilità genetici disponibili per i ratti 19,20, la combinazione di metodi di analisi comportamentale precisi e ben controllati con manipolazioni genetiche, l&#39;imaging e tecniche fisiologiche rappresenta una potente cassetta degli attrezzi per capire meglio le basi neurobiologiche di apprendimento motorio e della 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.

Acquisizione di abilità motoria di successo si ottiene solo attraverso la pratica costante. Nonostante un attento esame di tutti gli aspetti, alcuni ratti riescono a imparare il compito (Figura 2). Questi &quot;non discenti o mancanza di motivazione conseguente pochi o assenti tentativi di recupero pellet dall&#39;inizio dell&#39;esperimento o in generale perdono interesse nel raggiungere per il pellet che portano alla riuscita continuamente tentativi. Al contrario, alcuni animali mostrano un comportam...

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.

Acquisizione di un alta precisione specializzata arti anteriori Raggiungere Task in Rats

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

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

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Behavior

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

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

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

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

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

Valutare forelimb Funzione dopo unilaterale cervicale SCI utilizzando Compiti Novel: Arto Step-alternanza, instabilità posturale e Pasta Handling

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

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Comportamento

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;

Studio Skill Motor Learning by Single-pellet attività Raggiungere in topi

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 nuovo metodo per la valutazione delle funzioni zampa anteriore prossimale e distale del Ratto: la (IBB) Irvine, Beatties e Bresnahan Scala arti anteriori

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

Neuroscienze

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.

Indagare abilità motorie processi di apprendimento con un robot 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 struttura della zampa anteriore Skilled Raggiungere nel Ratto: una scala di valutazione 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.

L'attività di supinazione manopola: Un metodo semi-automatico per la valutazione della funzione degli arti anteriori in ratti

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.

Valutazione della prensione qualificata nei topi utilizzando un auto-allenatore

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.

Acquisto automatico di ratti a pellet con ricostruzione tridimensionale delle traiettorie di paw e cifre

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 Controllo optogenetico wireless del comportamento motorio qualificato

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

Valutazione della destrezza con esercizi di abilità

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