Neurosciences

Nicotine reduces antisaccade errors in task impaired schizophrenic subjects

by Abigail Larrison

Toward a second-person neuroscience

by Bert Timmermans

Schilbach L and* Timmermans B, Reddy V, Costall A, Bente G, Schlicht T, & Vogeley K. Toward a second-person neuroscience. Behavioral and Brain Sciences, target article accepted for publication. *equal contributions

In spite of the remarkable progress made in the burgeoning field of social neuroscience, the neural mechanisms that... more In spite of the remarkable progress made in the burgeoning field of social neuroscience, the neural mechanisms that underlie social encounters are only beginning to be studied and could —paradoxically— be seen as representing the ‘dark matter’ of social neuroscience. Recent conceptual and empirical developments consistently indicate the need for investigations, which allow the study of real-time social encounters in a truly interactive manner. This suggestion is based on the premise that social cognition is fundamentally different when we are in interaction with others rather than merely observing them. In this article, we outline the theoretical conception of a second-person approach to other minds and review evidence from neuroimaging, psychophysiological studies and related fields to argue for the development of a second-person neuroscience, which will help neuroscience to really go social; this may also be relevant for our understanding of psychiatric disorders construed as disorders of social cognition.

Cellular therapies for treating pain associated with spinal cord injury. Leung, L.

by Lawrence Leung

Journal of Translational Medicine 2012, 10:37

Spinal cord injury leads to immense disability and loss of quality of life in human with no satisfactory clinical... more Spinal cord injury leads to immense disability and loss of quality of life in human with no satisfactory clinical cure. Cell-based or cell-related therapies have emerged as promising therapeutic potentials both in regeneration of spinal cord and mitigation of neuropathic pain due to spinal cord injury. This article reviews the various options and their latest developments with an update on their therapeutic potentials and clinical trialing.

Caracterización neuropsicológica de la impulsividad funcional y disfuncional en adictos a sustancias: implicaciones clínicas

by José María Ruiz Sánchez de León

Pedrero-Pérez, E.J., Ruiz-Sánchez de León, J.M., Rojo Mota, G., Llanero Luque, M. y Puerta-García, C. (2012). Neuropsychological characterization of functional and dysfunctional impulsivity in drug addicts: clinical implications [In Spanish]. Adicciones, 24(1), 51-58.

La impulsividad es una de las variables más consistentemente vinculadas a las distintas fases del proceso adictivo.... more La impulsividad es una de las variables más consistentemente vinculadas a las distintas fases del proceso adictivo. Sin embargo, casi siempre se ha estudiado como una condición negativa, vinculada a psicopatología. Dickman (1990) propuso dos tipos de impulsividad, una disfuncional (ID) y otra funcional (IF). A ésta última la definió como la tendencia a tomar decisiones rápidas, orientadas a metas, mediante un proceso de toma de decisiones con riesgo calculado. Pocos estudios han abordado la caracterización neuropsicológica de ambas variantes, relacionándolas con el rendimiento en pruebas clásicas. Una muestra de 52 sujetos adictos en tratamiento cumplimentó el Dickman Impulsivity Inventory y una batería de pruebas neuropsicológicas clásicas. Se observaron correlaciones de débiles a moderadas entre la IF e indicadores de éxito en las tareas neuropsicológicas, mientras que la ID mostró una relación difusa y débiles correlaciones con indicadores de mal rendimiento en todas las tareas. La ID se mostró como una disposición que dificulta la realización de las tareas de forma global, sin interferencia específica, en tanto que la IF se relacionó consistentemente con mayor precisión, menor número de errores y mejor mantenimiento de los planes, y ello a partir de una mejor gestión atencional y una mayor resistencia al ruido. Se sugieren las implicaciones de cara a los tratamientos de las adicciones.

Palabras clave: Impulsividad funcional, impulsividad disfuncional, evaluación neuropsicológica, adicción, tratamiento, atención, funciones ejecutivas.

Impulsivity is a stable correlate throughout the course of drug addiction. However, it has always been studied as a negative condition, linked to psychopathology. Dickman (1990) proposed two subdimensions of impulsivity, dysfunctional (DI) and functional (FI). He defines the latter as the tendency for rapid, goal-oriented decision-making characterized by well calculated risks. Only a few studies have attempted to differentiate between these two subdimensions using classical neuropsychological tests. Fifty two drug addicts in treatment were tested using Dickman’s Impulsivity Inventory and a battery of classical neuropsychological tests. FI shows moderate to high correlations with many classical neuropsychological test scores in relation to enhanced executive functioning, whereas DI reveals surprisingly weak and scarce correlations with indicators of impaired executive functioning. DI appears to be a trait related to some difficulties in classical neuropsychological tests, while FI emerges as a consistent and much stronger predictor of higher attention capacity, lower distractibility, better precision, fewer errors, and better maintenance of goal-oriented strategies. Thus, functional impulsivity is related to positive conditions and more efficient cognitive functioning. Implications for the treatment of drug addictions are suggested.

Key words: Functional impulsivity, dysfunctional impulsivity, neuropsychological assessment, drug addiction, treatment, attention, executive functions.

Validación de un cuestionario de quejas cognitivas para adultos jóvenes: relación entre las quejas subjetivas de memoria, la sintomatología prefrontal y el estrés percibido

by José María Ruiz Sánchez de León

Lozoya-Delgado P, Ruiz-Sánchez de León JM, Pedrero-Pérez EJ. Validation of a cognitive complaints questionnaire for young adults: the relation between subjective memory complaints, prefrontal symptoms and perceived stress [In Spanish] Rev Neurol 2012; 54: 137-50.

Introducción. Las quejas subjetivas de memoria constituyen uno de los motivos de consulta más frecuentes a los... more Introducción. Las quejas subjetivas de memoria constituyen uno de los motivos de consulta más frecuentes a los servicios sanitarios, aunque apenas existen instrumentos validados en castellano para valorar su magnitud. Así como los cuestionarios de quejas de memoria habitualmente incluyen ítems referentes a aspectos atencionales y ejecutivos, se formulan hipótesis acerca de su relación con otros procesos dependientes de la integridad de la corteza prefrontal. Objetivo. Se trata de estudiar las propiedades psicométricas de un instrumento basado en el cuestionario de fallos de memoria de la vida cotidiana –Memory Failures Everyday (MFE)–, proporcionando una baremación sobre una amplia muestra de población española. Como objetivo secundario, se pretenden analizar las relaciones existentes entre la aparición de las quejas, la sintomatología de origen prefrontal y el estrés percibido. Sujetos y métodos. Se administran el MFE-30 (una modificación del MFE), el cuestionario disejecutivo y la escala de estrés percibido a una muestra de adultos jóvenes de población general no clínica (n = 900). Resultados. Los análisis muestran que el MFE-30 es un cuestionario unifactorial que valora un único constructo llamado ‘quejas cognitivas’. Además, se observa un intenso patrón de correlaciones entre dichas quejas, la sintomatología de origen prefrontal y el estrés percibido. Conclusiones. Los baremos aportados muestran que el MFE-30 es un instrumento útil en la práctica clínica. Los resultados encontrados están en consonancia con estudios anteriores, sugiriendo que existe una estrecha relación entre la aparición de quejas cognitivas, la presencia de sintomatología prefrontal y el estrés percibido.

Palabras clave. Atención. Corteza prefrontal. Cribado. DEX. Funciones ejecutivas. Lóbulos frontales. Memoria. Metamemoria. MFE. Neuropsicología. Quejas de memoria. Síndrome disejecutivo.

Introduction. Although subjective memory complaints are one of the most common causes behind visits to health services, there are hardly any validated instruments in Spanish for evaluating their magnitude. Since memory complaint questionnaires usually include items referring to attentional and executive aspects, it has been hypothesised that they may well be related with other processes that depend on the integrity of the prefrontal cortex. Aim. The purpose of this study was to examine the psychometric properties of an instrument based on the Memory Failures in Everyday (MFE) questionnaire, thus providing a valuation over a broad sample of the Spanish population. A second aim of the study was to analyse the relations that exist between the appearance of the complaints, the symptoms of a prefrontal origin and perceived stress. Subjects and methods. The MFE-30 (a modified version of the MFE), the dysexecutive questionnaire and the perceived stress scale were administered to a sample of young adults from a non-clinical general population (n = 900). Results. The analyses show that the MFE-30 is a single-factor questionnaire that evaluates a single construct called ‘cognitive complaints’. Moreover, an intense pattern of correlations among these complaints, the symptoms of a prefrontal origin and perceived stress is observed. Conclusions. The resulting scores show that the MFE-30 is a useful instrument in clinical practice. Findings are in line with those from previous studies, thus suggesting that there is a close relation among the appearance of cognitive complaints, the presence of prefrontal symptoms and perceived stress.

Key words. Attention. DEX. Dysexecutive syndrome. Executive functions. Frontal cortex. Frontal lobes. Memory complaints. Memory. Metamemory. MFE. Neuropsychology. Screening.

Propuesta de un protocolo para la evaluación neuropsicológica de las adicciones

by José María Ruiz Sánchez de León

A proposal for a protocol of neuropsychological assessment for use in addictions [In Spanish]. Revista de Neurología 2011; 53(8): 483-493.

Introducción. El interés por los procesos cerebrales implicados en la instauración, el mantenimiento y el abandono de... more Introducción. El interés por los procesos cerebrales implicados en la instauración, el mantenimiento y el abandono de las adicciones ha desencadenado que, en los últimos años, se hayan planteado algunos modelos neurocognitivos con un sustancial apoyo empírico. Sin embargo, existe la necesidad de un consenso en cuanto a las pruebas de valoración clínica que se pueden administrar y por qué hacerlo. El presente trabajo pretende recoger algunos de los tests neuropsicológicos más útiles para valorar a individuos adictos, así como las escalas de sintomatología cotidiana y pruebas de desempeño ocupacional que se han validado en castellano para esta población. Desarrollo. Los subprocesos cognitivos abordados en este trabajo, que han demostrado ser útiles en el diagnóstico sindrómico de las adicciones, son la velocidad de procesamiento, la atención selectiva y sostenida, la atención alternante y dividida, la amplitud atencional y el ejecutivo central, la memoria, la flexibilidad cognitiva y la fluidez, la inhibición de respuestas, la planificación, la abstracción, la toma de decisiones y, por último, la teoría de la mente. Se propone un protocolo en dos sesiones de 50 minutos, en el que la segunda sesión es opcional en función de la necesidad y la oportunidad en cada caso. Conclusión. El presente protocolo proporciona algunas ventajas importantes para los clínicos, como la sistematización, la posibilidad de replicación y convergencia entre evaluadores o la delimitación de los subprocesos susceptibles de evaluación compartiendo un mismo esquema, y, todo ello, en sesiones asequibles en cuanto a duración para casi todos los servicios que se dedican a atender a adictos que solicitan tratamiento.

Palabras clave. Abuso de drogas. Adicción. Amnesia. Atención. Corteza frontal. Déficit cognitivo. Deterioro cognitivo. Diagnóstico. Drogodependencias. Evaluación neuropsicológica. Funciones ejecutivas. Lóbulos frontales. Memoria. Neuropsicología. Síndrome disejecutivo. Trastorno cognitivo.


Introduction. Interest in the brain processes involved in establishing, maintaining and overcoming addictions has led to the development, in recent years, of a number of neurocognitive models with a substantial amount of empirical support. However, agreement still needs to be reached regarding the clinical evaluation tests that can be administered and the reason for doing so. The aim of this work is to outline some of the most useful neuropsychological tests for evaluating addicts, as well as the scales of day-to-day symptoms and occupational performance tests that have been validated in Spanish for this population. Development. The cognitive sub-processes addressed in this work, which have proved to be useful in the syndromic diagnosis of addictions, are processing speed, selective and sustained attention, alternating and divided attention, attentional amplitude and central executive, memory, cognitive flexibility and fluency, response inhibition, planning, abstraction, decision-making and, lastly, theory of mind. A protocol involving two 50-minute sessions is proposed, where the second session is optional depending on the needs and suitability in each case. Conclusions. This protocol offers several important advantages for physicians, including systemisation, the possibility of replication and convergence among evaluators or delimitation of the sub-processes that can be evaluated by sharing the same scheme. Moreover, it can all be carried out in sessions that are short enough to allow them to be offered by nearly all services that attend to addicts who request treatment.

Key words. Addiction. Amnesia. Attention. Cognitive deficit. Cognitive disorder. Cognitive impairment. Diagnosis. Drug abuse. Drug addiction. Dysexecutive syndrome. Executive functions. Frontal cortex. Frontal lobes. Memory. Neuropsychological evaluation. Neuropsychology.

Une nouvelle 'lisibilité du monde'. Les usages des neurosciences par les intermédiaires culturels en France (1970-2000)

by Sebastien Lemerle

published in 'Revue d'Histoire des Sciences Humaines', 2011, 25, 35-58

A new « legibility of the world ». The uses of the neurosciences by cultural go-betweens in France (1970-2000)more A new « legibility of the world ». The uses of the neurosciences by cultural go-betweens in France (1970-2000)

Neurosciences have been being very popular in France since the early 1980’s, thanks to acclaimed authors such as Jean-Pierre Changeux, Jean-Didier Vincent or Boris Cyrulnik. But this popularity cannot be fully understood if one does not take into account the multiple determination of the word « brain » in the public sphere. The study of the diffusion (through publishing or press) of neuroscientific discourses shows that their social visibility does not only come from the indeniable progress of research, but also from more global ideological and social evolutions, especially within mainstream cultural producers. Thus, the promotion of neurosciences on the French intellectual scene could have taken advantage of the tendency of some cultural go-betweens to consider social issues in an individualizing and psychologizing way.

Introspective Minds: Using ALE meta-analyses to study commonalities in the neural correlates of emotional processing, social & unconstrained cognition

by Bert Timmermans

Schilbach L, Bzdok D, Timmermans B, Fox PT, Laird AR, Vogeley K, & Eickhoff SB. (2012). Introspective Minds: Using ALE meta-analyses to investigate commonalities in the neural correlates of emotional processing, social & unconstrained cognition. PLoS ONE 7(2): e30920.

Previous research suggests overlap between brain regions that show task-induced deactivations and those activated... more Previous research suggests overlap between brain regions that show task-induced deactivations and those activated during the performance of social-cognitive tasks. Here, we present results of quantitative meta-analyses of neuroimaging studies, which confirm a statistical convergence in the neural correlates of social and resting state cognition. Based on the idea that both social and unconstrained cognition might be characterized by introspective processes, which are also thought to be highly relevant for emotional experiences, a third meta-analysis was performed investigating studies on emotional processing. By using conjunction analyses across all three sets of studies, we can demonstrate significant overlap of task-related signal change in dorso-medial prefrontal and medial parietal cortex, brain regions that have, indeed, recently been linked to introspective abilities. Our findings, therefore, provide evidence for the existence of a core neural network, which shows task-related signal change during socio-emotional tasks and during resting states.

Altered Neural and Behavioral Dynamics in Huntington's Disease: An Entropy Conservation Approach

by S. Lee Hong

Background

Huntington's disease (HD) is an inherited condition that results in neurodegeneration of the... more Background

Huntington's disease (HD) is an inherited condition that results in neurodegeneration of the striatum, the forebrain structure that processes cortical information for behavioral output. In the R6/2 transgenic mouse model of HD, striatal neurons exhibit aberrant firing patterns that are coupled with reduced flexibility in the motor system. The aim of this study was to test the patterns of unpredictability in brain and behavior in wild-type (WT) and R6/2 mice.

Methodology/Principal Findings

Striatal local field potentials (LFP) were recorded from 18 WT and 17 R6/2 mice (aged 8–11 weeks) while the mice were exploring a plus-shaped maze. We targeted LFP activity for up to 2 s before and 2 s after each choice-point entry. Approximate Entropy (ApEn) was calculated for LFPs and Shannon Entropy was used to measure the probability of arm choice, as well as the likelihood of making consecutive 90-degree turns in the maze. We found that although the total number of choice-point crossings and entropy of arm-choice probability was similar in both groups, R6/2 mice had more predictable behavioral responses (i.e., were less likely to make 90-degree turns and perform them in alternation with running straight down the same arm), while exhibiting more unpredictable striatal activity, as indicated by higher ApEn values. In both WT and R6/2 mice, however, behavioral unpredictability was negatively correlated with LFP ApEn.

Conclusions/Significance

HD results in a perseverative exploration of the environment, occurring in concert with more unpredictable brain activity. Our results support the entropy conservation hypothesis in which unpredictable behavioral patterns are coupled with more predictable brain activation patterns, suggesting that this may be a fundamental process unaffected by HD.

The network behind spatio‐temporal patterns: building low‐complexity retinal models in CNN based on morphology, pharmacology and physiology

by Erik Nemeth

Response to change is facilitated by a three-neuron disinhibitory pathway in the tiger salamander retina

by Erik Nemeth

Reduction in corticospinal inhibition in the trained and untrained limb following unilateral leg strength training.

by Alan Pearce

Latella, Kidgell, Pearce
European Journal of Applied Physiology (In Press).

‘‘Can It Read My Mind?’’ – What Do the Public and Experts Think of the Current (Mis)Uses of Neuroimaging?

by Oliver Escobar

A paper by Wardlaw et al. (2011) Public Library of Science ONE 6(10): e25829.

Open access: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0025829

Emerging applications of neuroimaging outside medicine and science have received intense public exposure through the... more Emerging applications of neuroimaging outside medicine and science have received intense public exposure through the media. Media misrepresentations can create a gulf between public and scientific understanding of the capabilities of neuroimaging and raise false expectations. To determine the extent of this effect and determine public opinions on acceptable uses and the need for regulation, we designed an electronic survey to obtain anonymous opinions from as wide a range of members of the public and neuroimaging experts as possible.

The surveys ran from 1st June to 30 September 2010, asked 10 and 21 questions, respectively, about uses of neuroimaging outside traditional medical diagnosis, data storage, science communication and potential methods of regulation. We analysed the responses using descriptive statistics; 660 individuals responded to the public and 303 individuals responded to the expert survey. We found evidence of public skepticism about the use of neuroimaging for applications such as lie detection or to determine consumer preferences and considerable disquiet about use by employers or government and about how their data would be stored and used. While also somewhat skeptical about new applications of neuroimaging, experts grossly underestimated how often neuroimaging had been used as evidence in court.

Although both the public and the experts rated highly the importance of a better informed public in limiting the inappropriate uses to which neuroimaging might be put, opinions differed on the need for, and mechanism of, actual regulation. Neuroscientists recognized the risks of inaccurate reporting of neuroimaging capabilities in the media but showed little motivation to engage with the public. The present study also emphasizes the need for better frameworks for scientific engagement with media and public education.

Dreaming (2010) in Atlas of Clinical Sleep Medicine

by Tore Nielsen

Cognition in REM and NREM sleep: A review and possible reconciliation of two models of sleep mentation (2000)

by Tore Nielsen

Sleep, dreaming and EEG coherence patterns in agenesis of the corpus callosum: comparisons with callosotomy patients (1994)

by Tore Nielsen

Nightmares: a new neurocognitive model (2007)

by Tore Nielsen

Nightmares, dreaming, and emotion regulation: A review (2007)

by Tore Nielsen

A satisfactory explanation of nightmares remains elusive. Theorists sinceFreud have speculated on mechanisms that... more A satisfactory explanation of nightmares remains elusive. Theorists sinceFreud have speculated on mechanisms that produce nightmares, but no single,widely accepted explanation has emerged (see Nielsen & Levin, 2007). This continuing uncertainty stems, in part, from the fact that nightmares, like dreams more generally, are expressions of human emotional memory-which itself is a complex and intransigent phenomenon. The inner workings of emotional memory have yet to be completely decoded, and the transformations of emotional memory that produce nlghtmares are even less well understood. This chapter provides a brief survey of theories and empirical research that have addressed the notion that dreaming serves an emotional regulation function and that nightmares are expressions of this function. We further suggest new directions for exploring nightmares and propose that emotional function may be linked especially to the socioemotional imagery of dreaming.

Topological basis of epileptogenesis in a model of severe cortical trauma

by Vladislav Volman

Calcium and synaptic dynamics underlying reverberatory activity in neuronal networks

by Vladislav Volman