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

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

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The authors have nothing to disclose

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

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

<table 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.

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

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

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

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

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

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

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

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

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.

A Task Congruência Crossmodal como um meio para se obter uma medida comportamental Objetivo no Rubber Mão 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 ...

Comportamento

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.

Um procedimento para estudar o efeito da restrição alimentar prolongada em heroína Buscando em ratos 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.

Medição de fronto-límbico Atividade Usando um emocional Oddball Task em Crianças com Familial alto risco para 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.

A reação de série 5-Choice Tempo Tarefa: A tarefa de atenção e controle de impulso 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.

Um procedimento para Observar Renovação induzida por Contexto de pavloviano condicionado Comportamento Álcool-seeking em Ratos

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

fMRI Validation of fNIRS Measurements During a Naturalistic Task

We present a method to compare brain activity recorded with near-infrared spectroscopy (fNIRS) in a dance video game task to that recorded in a reduced version of the task using fMRI (functional magnetic resonance imaging). Recently, it has been shown that fNIRS can accurately record functional brain activities equivalent to those concurrently recorded with functional magnetic resonance imaging for classic psychophysical tasks and simple finger tapping paradigms. However, an often quoted benefit of fNIRS is that the technique allows for studying neural mechanisms of complex, naturalistic behaviors that are not possible using the constrained environment of fMRI. Our goal was to extend the findings of previous studies that have shown high correlation between concurrently recorded fNIRS and fMRI signals to compare neural recordings obtained in fMRI procedures to those separately obtained in naturalistic fNIRS experiments. Specifically, we developed a modified version of the dance video game Dance Dance Revolution (DDR) to be compatible with both fMRI and fNIRS imaging procedures. In this methodology we explain the modifications to the software and hardware for compatibility with each technique as well as the scanning and calibration procedures used to obtain representative results. The results of the study show a task-related increase in oxyhemoglobin in both modalities and demonstrate that it is possible to replicate the findings of fMRI using fNIRS in a naturalistic task. This technique represents a methodology to compare fMRI imaging paradigms which utilize a reduced-world environment to fNIRS in closer approximation to naturalistic, full-body activities and behaviors. Further development of this technique may apply to neurodegenerative diseases, such as Parkinson&#8217;s disease, late states of dementia, or those with magnetic susceptibility which are contraindicated for fMRI scanning.

We present a method to compare functional brain activity recorded during a naturalistic task using fNIRS with activity recorded during fMRI.

fMRI Validação de fNIRS Medidas durante uma tarefa Naturalistic

We present a method to compare brain activity recorded with near-infrared spectroscopy (fNIRS) in a dance video game task to that recorded in a reduced ...

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.

The Hole Board Modificado - Medir Comportamento, Cognição e Interação Social em camundongos e ratos

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.

Quicar a bola com velocidade uniformemente variada em uma tarefa de sincronização do metrônomo

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.

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

Tasks that accurately measure dexterity in animal models are critical to understand hand function. Current rat behavioral tasks that measure dexterity ...

Evaluating Skilled Prehension in Mice Using an Auto-Trainer

We describe a method to introduce na&#239;ve mice to a novel prehension (reach-to-grasp) task. Mice are housed singly in cages with a frontal slot that permits the mouse to reach out of its cage and retrieve food pellets. Minimal food restriction is employed to encourage the mice to perform the food retrieval from the slot. As the mice begin to associate coming to the slot for food, the pellets are manually pulled away to stimulate extension and pronation of their paw to grasp and retrieve the pellet through the frontal slot. When the mice begin to reach for the pellets as they arrive at the slot, the behavioral assay can be performed by measuring the rate at which they successfully grasp and retrieve the desired pellet. They are then introduced to an auto-trainer that automates both the process of providing food pellets for the mouse to grasp, and the recording of successful and failed reaching and grasping attempts. This allows for the collection of reaching data for multiple mice with minimal effort, to be used in experimental analysis as appropriate.

Method to assess the impact of training on motor skills is a useful tool. Unfortunately, most behavioral assessments can be labor intensive and/or expensive.We describe here a robotic method of assessing prehension (reach-to-grasp) skill in mice.

Avaliando a Prehension qualificada em camundongos usando um instrutor automático

We describe a method to introduce na&#239;ve mice to a novel prehension (reach-to-grasp) task. Mice are housed singly in cages with a frontal slot that ...

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

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