LRH fue apoyada por la Ciencias e Ingeniería de Investigación Natural (NSERC), de Canadá. SD fue apoyado en parte por el programa de NSERC CREATE.

Todos los experimentos fueron aprobados por el comité de ética York y todos los participantes firmaron formularios de consentimiento informado. Los experimentos se realizaron de acuerdo con el Tratado de Helsinki. 1. Los estímulos <ol><li> Estímulo de detección táctiles <ol><li> Use un contactor (1.17 &quot;de diámetro y 0.30&quot; de espesor) para entregar estímulos táctiles de la vibración 250 Hz durante 100 ms. El uso de un contactor especialmente diseñada ofrece una relación lineal entre la cantidad de viajes y el voltaje aplicado. </li><li> Controlar el suministro de estímulo táctil con una tarjeta de sonido de 64 bits. <ol><li> Para conducir el contactor, lo tratan como un altavoz. Conectar un amplificador de audio estéreo a una tarjeta de sonido estéreo equipo de 64 bits. Conectar el contactor a una de las salidas del amplificador (por ejemplo, la &quot;izquierda altavoz hacia fuera &#39;). Conectar el segundo canal (por ejemplo, el &quot;altavoz derecho a cabo &#39;) del amplificador a un altavoz regular para proporcionar señales auditivas a la parpante. </li><li> En el código de ordenador que controla el experimento, generar la forma de onda que se utilizará para hacer vibrar el contactor (por ejemplo, una onda sinusoidal de 250 Hz de la duración de 100 ms), y otra forma de onda para la señal de sonido (por ejemplo, una onda sinusoidal 3000 Hz con una duración de 100 ms). Véase el ejemplo de código 1 en el archivo de código suplementario. </li><li> Ponga cada una de estas dos formas de onda en una matriz de dos dimensiones. Para la matriz contactor poner la señal en la primera dimensión y establecer la segunda dimensión a todos los ceros. Para la matriz de sonido poner la señal en la segunda dimensión y establecer el primero en todos los ceros. Juega la matriz adecuada para la tarjeta de sonido en el punto apropiado en el programa. Véase el ejemplo de código 1 en el archivo de código suplementario para una demostración de cómo se hace esto. </li></ol></li><li> Acople el contactor a una correa de sujeción con un producto basado en la mecánica. </li></ol></li><li> estímulo de enmascaramiento <ol><li> Proporcionar el estímulo de enmascaramiento por una eléctrica, jand-sostenido (4 cm de diámetro; 83 Hz cuando se encuentra en &quot;baja&quot;) vibrador. </li><li> Sobre la base de las áreas en las que el enmascaramiento se va a probar, seleccionar los sitios en los que el estímulo de enmascaramiento se va a aplicar. </li></ol></li></ol> 2. Configuración Experimental y Diseño <ol><li> Disponga el equipo y el equipo en un escritorio, una silla frente a ella, por el experimentador. </li><li> Establecer una mesa sobre la que descansan los participantes su brazo (prueba) a la izquierda. Coloque una silla para el lado derecho de la tabla. Ponga un stand reposabrazos al lado de la silla en la que los participantes descansar el codo (enmascaramiento brazo) derecha. Añadir amortiguación a la mesa y apoyabrazos para una mayor comodidad. </li><li> Organizar un altavoz en una superficie mecánicamente aislado. Organizar pedales (conectado a los botones izquierdo y derecho de un ratón de ordenador), de modo que los pies de los participantes van a descansar cómodamente en ellos (Figura 1). </li><li> Elija los parámetros del estudio, incluyendo el número apropiado de ensayos requeridospara obtener una estimación fiable del umbral (típicamente, entre 40 a 50 ensayos) y el número de bloques en el que el experimento se va a dividir (por ejemplo, dos bloques de 20-25 ensayos por condición). </li><li> Haga una lista de la orden en el que se ejecutarán las condiciones. Utilice esta lista para determinar dónde llevar a cabo el estímulo de enmascaramiento para cada bloque. </li><li> Introduce el número de ensayos directamente en el código de programa de ordenador (por ejemplo, ntrials = 25; Ver archivo de código suplementario). Asegúrese de que cada bloque ya no es de 10 minutos para mantener la atención. </li><li> Programar una forzada de dos alternativas de opción-tarea de detección táctil 11 en el que la intensidad del estímulo se controla con un procedimiento psicométrica escalera psicofísica adaptativo bayesiano 12. <ol><li> Para cada ensayo, presentes dos intervalos de 1 segundo, marcado por tres pitidos (5 kHz, 3 kHz y 5 kHz, duración de 100 ms), con el estímulo táctil presentado en medio de uno de los intervalos. Tener el participante indicate intervalo en el que el estímulo fue presentado por medio de pedales (de izquierda para el primer, segundo por la derecha). Ver Ejemplo de código 2, que muestra cómo los intervalos se ejecutan y se anotó. Nota: Las calificaciones de ordenador como la respuesta &quot;correcta&quot; o &quot;incorrecta&quot; y la escalera de adaptación selecciona el siguiente valor que se presentará en consecuencia. Nota: Este método determina un valor umbral para la detección de la vibración en el sitio de prueba. </li></ol></li></ol><img alt="Figura 1" src="/files/ftp_upload/53733/53733fig1.jpg" /> Figura 1. Diseño experimental. Esta figura muestra la puesta en marcha del experimento y los materiales utilizados. Véase el texto para más detalles. 3. Procedimiento experimental <ol><li> Obtener el consentimiento informado por escrito. Asentar el participante en la silla con sus pies descansando cómodamente en los pedales de respuesta y explicar el procedimiento experimental. &lt;/ Li&gt; <li> Medir y registrar la longitud de la superficie dorsal del antebrazo izquierdo. Aplicar la correa de modo que el contactor se coloca en el medio de la mitad del brazo entre el ángulo interno del codo y el pliegue de la muñeca. </li><li> Envolver un vendaje tensor libremente alrededor del brazo varias veces para mantener el contactor en su lugar. </li><li> Instruir a los participantes a poner su brazo izquierdo sobre la mesa y descansar su codo derecho en el reposabrazos. Venda de los ojos del participante para evitar que mirar el estímulo o enmascarar lugar y darles instrucciones para mirar hacia adelante a lo largo del experimento. </li><li> Comience con un bloque de 20 ensayos de práctica (sin el estímulo de enmascaramiento) con el fin de familiarizar a los participantes con la tarea de detección táctil y que les permita familiarizarse con los estímulos táctiles. </li><li> A raíz de los ensayos de práctica, comenzar el experimento, la ejecución de los bloques de condiciones en un orden aleatorio, con contrapeso. Antes de comenzar cada bloque, garantizar que las armas y el enmascaramiento Stimulus están en las posiciones correctas. <ol><li> Para cada condición, mantenga el estímulo de enmascarar en el sitio elegido, en referencia a la lista de las condiciones anteriores. Tachar cada condición en que se ejecuta. Mantenga el estímulo de enmascarar lo largo de cada bloque de ensayos de recogida de datos se mantiene la presión aproximadamente constante. El estímulo de enmascaramiento se puede aplicar a través de la tela delgada. </li><li> Ejecutar el programa experimental que se desarrollará a través de un número determinado de intentos, lo que previamente seleccionada. Introducir un período de descanso de 2 minutos después de cada secuencia corta de los ensayos. Después de que se complete un bloque determinado de ensayos, seleccione el siguiente sitio para el estímulo de enmascaramiento y ejecutar el programa de nuevo. Repita hasta que se hayan completado todos los ensayos. </li></ol></li></ol> Análisis 4. Datos <ol><li> Para visualizar y confirmar la estimación del valor de umbral devuelto por el programa de escalera de adaptación 12, ajustar los datos de los participantes con una gaussiana acumulativa La fórmula para una gaussiana acumulativa(Sigmoide) que va desde el 50% (nivel de azar - igual número de 0s - mal y 1&#39;s- correcta) a 100% (todo de 1, los correctos) es: probabilidad de una respuesta correcta = 0,5 + 0,5 / (1 + exp (- (x-x0) / std)) donde x es el valor de la intensidad probado, x0 es el valor umbral de 75%, y std es la desviación estándar de la estimación. Esta fórmula se puede ajustar a los datos utilizando el software de ajuste de curvas y el valor x0 resultante en comparación con el valor adaptativo escalera. <ol><li> Asegúrese de que la curva va entre 50% (rendimiento de probabilidad) y 100%. Llevar a cabo análisis estadísticos (por ejemplo, pruebas t o ANOVA) en los valores umbral del 75% obtenidos en cada condición del experimento (por ejemplo, entre los diferentes sitios de enmascaramiento) para determinar si hay diferencias entre las condiciones ensayadas. </li></ol></li><li> Con el fin de identificar los valores atípicos, calcular la media y la desviación estándar para una condición dada. Comparar la puntuación de cada participante con la media y lasi una puntuación individual es más de 2 desviación estándar a partir de ese entonces significa considerar esta partitura como un valor atípico y sacarlo del análisis. Criterios alternativos se pueden usar si se desea. </li><li> Para estandarizar los valores de la intensidad de los contactores (que están en en unidades arbitrarias), las convierten en decibelios con relación a los umbrales de control (medidos cuando el estímulo de enmascaramiento se aplica al sitio de control, por ejemplo, el hombro). Utilice esta fórmula: dB = 10 x log 10 (valor umbral de valor umbral / control). </li></ol>

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Los autores declaran que no tienen intereses financieros en competencia.

Aquí, se describe un protocolo detallado para el enmascaramiento táctil contralateral y los resultados publicados anteriormente utilizando la técnica de poner a prueba los umbrales de detección táctiles se muestran. La ventaja de este método es que los umbrales se miden utilizando una técnica psychophysically riguroso. La elección forzada procedimiento de dos alternativa (2AFC) es relativamente insensible a sesgo de respuesta y por lo tanto de los efectos de atención. El procedimiento escalera de adaptación pa...

enmascaramiento táctil es donde un estímulo táctil en un lugar en el cuerpo altera la percepción de un toque en otro lugar. Esta es una técnica por primera vez por von Békésy 1 para revelar interacciones ubicación, especialmente la inhibición lateral, entre las zonas de la piel que son adyacentes en la superficie del cuerpo. Mientras enmascaramiento táctil se ha estudiado ampliamente en los últimos años, la investigación ha investigado sobre todo enmascaramiento ipsilateral táctil mediante la estimulación eléctrica 2, 3, 4 presión, y la estimulación vibrotáctil 5, 6. Por el contrario, pocos estudios han examinado el enmascaramiento contralateral táctil en la que los sitios de enmascaramiento y las sondas pueden ser quitados lejos. De largo alcance efectos de enmascaramiento táctiles se han mostrado entre los puntos de simetría de espejo en la mano y el brazo 5, 7 - 9, pero estos estudios se han limitado en gran medida a mirar las manos y los dedos 7, 10, con más extensas partes de todo el cuerpo está en gran medida ignorados. Uno de los objetivos de tales experimentos de enmascaramiento de largo alcance es indicar cómo los componentes de la representación del cuerpo en el cerebro pueden estar relacionados funcionalmente. Aquí, el fenómeno de largo alcance enmascaramiento táctil es explorado por la investigación de cómo la vibración aplicada a un antebrazo podría afectar umbrales de sensibilidad táctil en el antebrazo opuesto. Umbral se refiere al estímulo mínimo que se necesita para detectar un estímulo. Definimos esto como la intensidad a la que se detecta el estímulo 75% del tiempo. Se utilizó una técnica de enmascaramiento táctil en la que la sensibilidad táctil (el recíproco de umbral) en un antebrazo se mide en la presencia de un estímulo vibratorio (la máscara) en otra parte del cuerpo. Enmascaramiento efectivo es revelado por un aumento en el umbral de detección es decir, una reducción de la sensibilidad. La técnica se puede utilizar en combinación con otras manipulaciones tales como variando posición de las extremidades or movimiento para explorar sus efectos sobre la eficacia de enmascaramiento. Aquí hemos utilizado estímulos vibrotactile como el estímulo de enmascaramiento. La ventaja de esto es que la frecuencia, y por lo tanto el tipo de receptor que estimula pueden ser controlados. La técnica podría extenderse a mirar dolor utilizando estímulos eléctricos como la sonda o máscara o ambos. También, cualquier sitio puede utilizarse como el sitio de enmascaramiento que permite la investigación de los sitios de acupuntura por ejemplo.

<table border="0" cellpadding="0" cellspacing="0" width="673">
	<tbody>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">C-2 tactor</td>
			<td style="width:127px;">ATAC Technology; Engineering Acoustics, Inc.</td>
			<td style="width:164px;"></td>
			<td style="width:167px;">http://www.atactech.com/PR_tactors.html</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Magic Wand</td>
			<td style="width:127px;">Hitachi</td>
			<td style="width:164px;"></td>
			<td style="width:167px;">http://magicwandoriginal.com/magic-wand-original/</td>
		</tr>
		<tr height="105">
			<td height="105" style="height:105px;width:216px;">FC5 Foot Pedals</td>
			<td style="width:127px;">Yamaha Corporation</td>
			<td style="width:164px;"></td>
			<td style="width:167px;">http://ca.yamaha.com/en/products/music-production/accessories/footpedals/fc5/?mode=model</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">MATLAB</td>
			<td style="width:127px;">The Mathworks, Inc.</td>
			<td style="width:164px;"></td>
			<td style="width:167px;">http://www.mathworks.com/products/matlab/</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Velcro</td>
			<td style="width:127px;">Velcro Industries B.V.</td>
			<td style="width:164px;"></td>
			<td>http://www.velcro.com/</td>
		</tr>
	</tbody>
</table>

testing tactile masking between the forearms

Masking, in which one stimulus affects the detection of another, is a classic technique that has been used in visual, auditory, and tactile research, usually using stimuli that are close together to reveal local interactions. Masking effects have also been demonstrated in which a tactile stimulus alters the perception of a touch at a distant location. Such effects can provide insight into how components of the body's representations in the brain may be linked. Occasional reports have indicated that touches on one hand or forearm can affect tactile sensitivity at corresponding contralateral locations. To explore the matching of corresponding points across the body, we can measure the spatial tuning and effect of posture on contralateral masking. Careful controls are required to rule out direct effects of the remote stimulus, for example by mechanical transmission, and also attention effects in which thresholds may be altered by the participant's attention being drawn away from the stimulus of interest. The use of this technique is beneficial as a behavioural measure for exploring which parts of the body are functionally connected and whether the two sides of the body interact in a somatotopic representation. This manuscript describes a behavioural protocol that can be used for studying contralateral tactile masking.

Los análisis de los datos se informaron en el 13. Sensibilidad táctil (expresado en relación con los umbrales medidos en la condición de control) en el antebrazo se redujo significativamente (umbrales se incrementaron significativamente) cuando la estimulación vibrotáctil enmascaramiento se aplicó al brazo opuesto (figura 2A), lo que demuestra un efecto de enmascaramiento contralateral entre antebrazos. El efecto dependía de la posición del estímulo ...

Watch this Scientific Journal Video about Testing Tactile Masking between the Forearms at JoVE.com

Testing Tactile Masking between the Forearms

Las pruebas táctil enmascaramiento entre los antebrazos

Here we explore contralateral tactile masking between the forearms in which tactile detection thresholds are modulated by vibration applied to a remote site. The details of which remote sites have an effect can tell us about how the body is represented in the brain.

Masking, in which one stimulus affects the detection of another, is a classic technique that has been used in visual, auditory, and tactile research, ...

testing-tactile-masking-between-the-forearms

Research

JoVE Journal

Behavior

6.3K vistas.  York University. Here we explore contralateral tactile masking between the forearms in which tactile detection thresholds are modulated by vibration applied to a remote site. The details of which remote sites have an effect can tell us about how the body is represented in the brain. 

Video: Testing Tactile Masking between the Forearms

Quantitative Assessment of Cortical Auditory-tactile Processing in Children with Disabilities

Objective and easy measurement of sensory processing is extremely difficult in nonverbal or vulnerable pediatric patients. We developed a new methodology to quantitatively assess children&#39;s cortical processing of light touch, speech sounds and the multisensory processing of the 2 stimuli, without requiring active subject participation or causing children discomfort. To accomplish this we developed a dual channel, time and strength calibrated air puff stimulator that allows both tactile stimulation and sham control. We combined this with the use of event-related potential methodology to allow for high temporal resolution of signals from the primary and secondary somatosensory cortices as well as higher order processing. This methodology also allowed us to measure a multisensory response to auditory-tactile stimulation.

Objective and easy measurement of sensory processing is extremely difficult in nonverbal or vulnerable pediatric patients. We developed a new methodology to quantitatively assess infants and children&#39;s cortical processing of light touch, speech sounds, and the multisensory processing of the 2 stimuli, without requiring active subject participation or causing discomfort in vulnerable patients.

Evaluación cuantitativa de procesamiento cortical auditivo-táctil en Niños con Discapacidades

Objective and easy measurement of sensory processing is extremely difficult in nonverbal or vulnerable pediatric patients. We developed a new methodology ...

Investigación

Comportamiento

Simple and Computer-assisted Olfactory Testing for Mice

Olfaction is highly conserved among species and is required for reproduction and survival.
In humans, olfaction is also one of the senses that is affected with aging and is a strong predictor of neurodegenerative diseases. Thus, olfaction testing is used as a non-invasive diagnostic method to detect neurological deficits early on. In order to understand the mechanisms underlying olfactory network susceptibility, olfactory research in rodents has gained momentum in the past decade.
Here, we present a very simple, time efficient and reproducible olfactory testing method of innate odor perception and sensitivity in mice without the need of any prior food or water restriction. The tests are performed in a familiar environment to the mice, require only the scents and a 2 min session of odorant exposure. The analysis is performed, post-hoc, using computer-assisted commands on ImageJ and can be, therefore, carried out from start to end by one researcher.
This protocol does not require any special hardware or setup and is indicated for any laboratory interested in testing olfactory perception and sensitivity.

We present a simple and unbiased olfactory test in mice. With this protocol olfactory discrimination, preference, avoidance and sensitivity to a novel odor as compared to water can be assessed in single behavioral sessions. This method is indicated for a single experimenter and analysis is based on computer-assisted video processing.

Simple y asistida por ordenador de pruebas olfativas para Ratones

Olfaction is highly conserved among species and is required for reproduction and survival.
In humans, olfaction is also one of the senses that is affected ...

Measurement of Vibration Detection Threshold and Tactile Spatial Acuity in Human Subjects

Tests that allow the precise determination of psychophysical thresholds for vibration and grating orientation provide valuable information about mechanosensory function that are relevant for clinical diagnosis as well as for basic research. Here, we describe two psychophysical tests designed to determine the vibration detection threshold (automated system) and tactile spatial acuity (handheld device). Both procedures implement a two-interval forced-choice and a transformed-rule up and down experimental paradigm. These tests have been used to obtain mechanosensory profiles for individuals from distinct human cohorts such as twins or people with sensorineural deafness.

Here, we present protocols to determine vibration detection thresholds and tactile acuity using psychophysical methods in man.

La medición de Umbral de detección de vibraciones y táctil espacial Agudeza en sujetos humanos

Tests that allow the precise determination of psychophysical thresholds for vibration and grating orientation provide valuable information about ...

A Mouse Model of Subchronic and Mild Social Defeat Stress for Understanding Stress-induced Behavioral and Physiological Deficits

Stressful life events often increase the incidence of depression in humans. To study the mechanisms of depression, the development of animal models of depression is essential. Because there are several types of depression, various animal models are needed for a deeper understanding of the disorder. Previously, a mouse model of subchronic and mild social defeat stress (sCSDS) using a modified chronic social defeat stress (CSDS) paradigm was established. In the paradigm, to reduce physical injuries from aggressors, the duration of physical contact between the aggressor and a subordinate was reduced compared to in the original CSDS paradigm. sCSDS mice showed increased body weight gain, food intake, and water intake during the stress period, and their social behaviors were suppressed after the stress period. In terms of the face validity of the stress-induced overeating and overdrinking following the increased body weight gain, the sCSDS mice may show some features related to atypical depression in humans. Thus, a mouse model of sCSDS may be useful for studying the pathogenic mechanisms underlying depression. This protocol will help establish the sCSDS mouse model, especially for studying the mechanisms underlying stress-induced weight gain and polydipsia- and hyperphagia-like symptoms.

Here, methods for developing a mouse model of subchronic and mild social defeat stress are described and used to investigate the pathogenic features of depression including hyperphagia- and polydipsia-like symptoms following increased body weight.

Un modelo de ratón de subcrónica y leve estrés Derrota Social para Entender déficits conductuales y fisiológicos inducidos por el estrés

Stressful life events often increase the incidence of depression in humans. To study the mechanisms of depression, the development of animal models of ...

Comparing the Frequency Effect Between the Lexical Decision and Naming Tasks in Chinese

In psycholinguistic research, the frequency effect can be one of the indicators for eligible experimental tasks that examine the nature of lexical access. Usually, only one of those tasks is chosen to examine lexical access in a study. Using two exemplar experiments, this paper introduces an approach to include both the lexical decision task and the naming task in a study. In the first experiment, the stimuli were Chinese characters with frequency and regularity manipulated. In the second experiment, the stimuli were switched to Chinese two-character words, in which the word frequency and the regularity of the leading character were manipulated. The logic of these two exemplar experiments was to explore some important issues such as the role of phonology on recognition by comparing the frequency effect between both the tasks. The results revealed different patterns of lexical access from those reported in the alphabetic systems. The results of Experiment 1 manifested a larger frequency effect in the naming task as compared to the LDT, when the stimuli were Chinese characters. And it is noteworthy that, in Experiment 1, when the stimuli were regular Chinese characters, the frequency effect observed in the naming task was roughly equivalent to that in the LDT. However, a smaller frequency effect was shown in the naming task as compared to the LDT, when the stimuli were switched to Chinese two-character words in Experiment 2. Taking advantage of the respective demands and characteristics in both tasks, researchers can obtain a more complete and precise picture of character/word recognition.

Researchers adopt both the lexical decision task and the naming task to investigate some important topics such as character/word recognition by comparing the frequency effect between these two tasks. This article introduces this approach through two exemplar experiments and elaborates on the underlying logic.

La comparación de la frecuencia de efecto entre la decisión de léxico y las tareas de denominación en chino

In psycholinguistic research, the frequency effect can be one of the indicators for eligible experimental tasks that examine the nature of lexical access. ...

Neurodevelopmental Reflex Testing in Neonatal Rat Pups

Neurodevelopmental reflex testing is commonly used in clinical practice to assess the maturation of the nervous system. Neurodevelopmental reflexes are also referred to as primitive reflexes. They are sensitive and consistent with later outcomes. Abnormal reflexes are described as an absence, persistence, reappearance, or latency of reflexes, which are predictive indices of infants that are at high risk for neurodevelopmental disorders. Animal models of neurodevelopmental disabilities, such as cerebral palsy, often display aberrant developmental reflexes, as would be observed in human infants. The techniques described assess a variety of neurodevelopmental reflexes in neonatal rats. Neurodevelopmental reflex testing offers the investigator a testing method that is not otherwise available in such young animals. The methodology presented here aims to assist investigators in examining developmental milestones in neonatal rats as a method of detecting early-onset brain injury and/or determining the effectiveness of therapeutic interventions. The methodology presented here aims to provide a general guideline for investigators.

Behavioral testing is the gold standard for determining outcomes following brain injury, and can identify the presence of developmental disabilities in infants and children. Neurodevelopmental reflexes are an early indicator of these abnormalities. A host of easily accomplished developmental reflex tests in the neonatal rodent were developed and described here.

Neurodesarrollo pruebas de reflejos neonatales en crías de rata

Neurodevelopmental reflex testing is commonly used in clinical practice to assess the maturation of the nervous system. Neurodevelopmental reflexes are ...

Using Wavelet Entropy to Demonstrate how Mindfulness Practice Increases Coordination between Irregular Cerebral and Cardiac Activities

In both the East and West, traditional teachings say that the mind and heart are somehow closely correlated, especially during spiritual practice. One difficulty in proving this objectively is that the natures of brain and heart activities are quite different. In this paper, we propose a methodology that uses wavelet entropy to measure the chaotic levels of both electroencephalogram (EEG) and electrocardiogram (ECG) data and show how this may be used to explore the potential coordination between the mind and heart under different experimental conditions. Furthermore, Statistical Parametric Mapping (SPM) was used to identify the brain regions in which the EEG wavelet entropy was the most affected by the experimental conditions. As an illustration, the EEG and ECG were recorded under two different conditions (normal rest and mindful breathing) at the beginning of an 8-week standard Mindfulness-based Stress Reduction (MBSR) training course (pretest) and after the course (posttest). Using the proposed method, the results consistently showed that the wavelet entropy of the brain EEG decreased during the MBSR mindful breathing state as compared to that during the closed-eye resting state. Similarly, a lower wavelet entropy of heartrate was found during MBSR mindful breathing. However, no difference in wavelet entropy during MBSR mindful breathing was found between the pretest and posttest. No correlation was observed between the entropy of brain waves and the entropy of heartrate during normal rest in all participants, whereas a significant correlation was observed during MBSR mindful breathing. Additionally, the most well-correlated brain regions were located in the central areas of the brain. This study provides a methodology for the establishment of evidence that mindfulness practice (i.e., mindful breathing) may increase the coordination between mind and heart activities.

This manuscript describes how to use the wavelet entropy index to analyze high-density electroencephalography (EEG) and electrocardiography (ECG) data. We show that the irregularity of cerebral and cardiac activities became more coordinated during mindfulness-based stress reduction practice.

Usando la Entropía Wavelet para Demostrar cómo la Práctica de Atención Plena Aumenta la Coordinación entre las Actividades Cerebrales y Cardíacas Irregulares

In both the East and West, traditional teachings say that the mind and heart are somehow closely correlated, especially during spiritual practice. One ...

The (Spatial) Memory Game: Testing the Relationship Between Spatial Language, Object Knowledge, and Spatial Cognition

The memory game paradigm is a behavioral procedure to explore the relationship between language, spatial memory, and object knowledge. Using two different versions of the paradigm, spatial language use and memory for object location are tested under different, experimentally manipulated conditions. This allows us to tease apart proposed models explaining the influence of object knowledge on spatial language (e.g., spatial demonstratives), and spatial memory, as well as understanding the parameters that affect demonstrative choice and spatial memory more broadly. Key to the development of the method was the need to collect data on language use (e.g., spatial demonstratives: &#34;this/that&#34;) and spatial memory data under strictly controlled conditions, while retaining a degree of ecological validity. The language version (section 3.1) of the memory game tests how conditions affect language use. Participants refer verbally to objects placed at different locations (e.g., using spatial demonstratives: &#34;this/that red circle&#34;). Different parameters can be experimentally manipulated: the distance from the participant, the position of a conspecific, and for example whether the participant owns, knows, or sees the object while referring to it. The same parameters can be manipulated in the memory version of the memory game (section 3.2). This version tests the effects of the different conditions on object-location memory. Following object placement, participants get 10 seconds to memorize the object&#39;s location. After the object and location cues are removed, participants verbally direct the experimenter to move a stick to indicate where the object was. The difference between the memorized and the actual location shows the direction and strength of the memory error, allowing comparisons between the influences of the respective parameters.

The Spatial Memory Game: Testing the Relationship Between Spatial Language, Object Knowledge, and Spatial Cognition

We present a protocol to explore the relationship between spatial language production, spatial memory, and object knowledge. The procedure allows experimental manipulation of, and control over, conditions of object knowledge, language at instruction, and physical location, thus teasing apart cognitive and linguistic models describing interactions between these variables.

El juego de memoria (espacial): Prueba de la relación entre el lenguaje espacial, objeto de conocimiento y cognición espacial

The memory game paradigm is a behavioral procedure to explore the relationship between language, spatial memory, and object knowledge. Using two different ...

Applying Incongruent Visual-Tactile Stimuli during Object Transfer with Vibro-Tactile Feedback

The application of incongruent sensory signals that involves disrupted tactile feedback is rarely explored, specifically with the presence of vibrotactile feedback (VTF). This protocol aims to test the effect of VTF on the response to incongruent visual-tactile stimuli. The tactile feedback is acquired by grasping a block and moving it across a partition. The visual feedback is a real-time virtual presentation of the moving block, acquired using a motion capture system. The congruent feedback is the reliable presentation of the movement of the block, so that the subject feels that the block is grasped and see it move along with the path of the hand. The incongruent feedback appears as the movement of the block diverts from the actual movement path, so that it seems to drop from the hand when it is actually still held by the subject, thereby contradicting the tactile feedback. Twenty subjects (age 30.2 &#177; 16.3) repeated 16 block transfers, while their hand was hidden. These were repeated with VTF and without VTF (total of 32 block transfers). Incongruent stimuli were presented randomly twice within the 16 repetitions in each condition (with and without VTF). Each subject was asked to rate the difficulty level of performing the task with and without the VTF. There were no statistically significant differences in the length of the hand paths and durations between transfers recorded with congruent and incongruent visual-tactile signals &#8211; with and without the VTF. The perceived difficulty level of performing the task with the VTF significantly correlated with the normalized path length of the block with VTF (r = 0.675, p = 0.002). This setup is used to quantify the additive or reductive value of VTF during motor function that involves incongruent visual-tactile stimuli. Possible applications are prosthetics design, smart sport-wear, or any other garments that incorporate VTF.

We present a protocol to apply incongruent visual-tactile stimuli during an object transfer task. Specifically, during block transfers, performed while the hand is hidden, a virtual presentation of the block shows random occurrences of false block drops. The protocol also describes adding vibrotactile feedback while performing the motor task.

Aplicación de estímulos visuales-táctiles incongruentes durante la transferencia de objetos con retroalimentación Vibro-táctil

The application of incongruent sensory signals that involves disrupted tactile feedback is rarely explored, specifically with the presence of vibrotactile ...

Human Circadian Phenotyping and Diurnal Performance Testing in the Real World

In our continuously developing &#39;around the clock&#39; society, there is a need to increase our understanding of how changes in biology, physiology and psychology influence our health and performance. Embedded within this challenge, is the increasing need to account for individual differences in sleep and circadian rhythms, as well as to explore the impact of time of day on performance in the real world. There are a number of ways to measure sleep and circadian rhythms from subjective questionnaire-based methods to objective sleep/wake monitoring, actigraphy and analysis of biological samples. This paper proposes a protocol that combines multiple techniques to categorize individuals into Early, Intermediate or Late circadian phenotype groups (ECPs/ICPs/LCPs) and recommends how to conduct diurnal performance testing in the field. Representative results show large differences in rest-activity patterns derived from actigraphy, circadian phase (dim light melatonin onset and peak time of cortisol awakening response) between circadian phenotypes. In addition, significant differences in diurnal performance rhythms between ECPs and LCPs emphasizes the need to account for circadian phenotype. In summary, despite the difficulties in controlling influencing factors, this protocol allows a real-world assessment of the impact of circadian phenotype on performance. This paper presents a simple method to assess circadian phenotype in the field and supports the need to consider time of day when designing performance studies.

Here, we present a method to investigate diurnal rhythms in performance following accurate categorization of participants into circadian phenotype groups based on the Munich ChronoType Questionnaire, gold standard circadian phase biomarkers and actigraphic measures.

Fenotipado circadiano humano y pruebas de rendimiento diurno en el mundo real

In our continuously developing &#39;around the clock&#39; society, there is a need to increase our understanding of how changes in biology, physiology and ...