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1.
Proc Natl Acad Sci U S A ; 108(37): 15408-13, 2011 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-21876148

RESUMEN

Cortical areas that directly receive sensory inputs from the thalamus were long thought to be exclusively dedicated to a single modality, originating separate labeled lines. In the past decade, however, several independent lines of research have demonstrated cross-modal responses in primary sensory areas. To investigate whether these responses represent behaviorally relevant information, we carried out neuronal recordings in the primary somatosensory cortex (S1) and primary visual cortex (V1) of rats as they performed whisker-based tasks in the dark. During the free exploration of novel objects, V1 and S1 responses carried comparable amounts of information about object identity. During execution of an aperture tactile discrimination task, tactile recruitment was slower and less robust in V1 than in S1. However, V1 tactile responses correlated significantly with performance across sessions. Altogether, the results support the notion that primary sensory areas have a preference for a given modality but can engage in meaningful cross-modal processing depending on task demand.


Asunto(s)
Discriminación en Psicología/fisiología , Tacto/fisiología , Corteza Visual/fisiología , Percepción Visual/fisiología , Potenciales de Acción/fisiología , Animales , Conducta Exploratoria/fisiología , Masculino , Neuronas/fisiología , Reconocimiento Visual de Modelos/fisiología , Ratas , Ratas Long-Evans , Vibrisas/fisiología
2.
Schizophr Res ; 252: 13-22, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36610221

RESUMEN

Visual illusions have long been used as tools to investigate sensory-perceptual deficits in schizophrenia. Recent conflicting accounts have called into question the assumption of abnormal illusion perception in patients and, therefore, the validity of this approach. Here, we present a systematic review of the current evidence regarding visual illusion perception abnormalities in patients with schizophrenia. Relevant publications were identified by a systematic search of PubMed, Literatura LILACS, PsycINFO, Embase, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), IBECS, BIOSIS, and Web of Science. Forty-five studies were selected which included illusions classified as 'Motion illusions', 'Geometric-optical illusions', 'Illusory contours', 'Depth inversion illusion', and 'Non-specific'. There is concordant evidence of abnormal processing of illusions in patients for most categories, especially in facial Depth Inversion and Müller-Lyer illusions. There were significant methodological disparities and shortcomings, but risk of bias was overall low for individual studies. The usefulness of visual illusions as tools in clinical settings as well as in basic research may be contingent on significant methodological refinements.


Asunto(s)
Percepción de Forma , Ilusiones , Ilusiones Ópticas , Esquizofrenia , Humanos , Percepción Visual
3.
Front Behav Neurosci ; 15: 641776, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34122024

RESUMEN

The Müller-Lyer Illusion (MLI) has been suggested as a potential marker for the perceptual impairments observed in schizophrenia patients. Along with some positive symptoms, these deficits are not easily modeled in rodent experiments, and novel animal models are warranted. Previously, MK-801 was shown to reduce susceptibility to MLI in monkeys, raising the prospects of an effective perception-based model. Here, we evaluate the translational feasibility of the MLI task under NMDA receptor blockage as a primate model for schizophrenia. In Experiment 1, eight capuchin monkeys (Sapajus spp.) were trained on a touchscreen MLI task. Upon reaching the learning criteria, the monkeys were given ketamine (0.3 mg/kg; i.m.) or saline on four consecutive days and then retested on the MLI task. In Experiment 2, eight chronic schizophrenia patients (and eight matching controls) were tested on the Brentano version of the MLI. Under saline treatment, monkeys were susceptible to MLI, similarly to healthy human participants. Repeated ketamine administrations, however, failed to improve their performance as previous results with MK-801 had shown. Schizophrenic patients, on the other hand, showed a higher susceptibility to MLI when compared to healthy controls. In light of the present and previous studies, the MLI task shows consistent results across monkeys and humans. In spite of potentially being an interesting translational model of schizophrenia, the MLI task warrants further refinement in non-human primates and a broader sample of schizophrenia subtypes.

4.
Neurosci Lett ; 736: 135300, 2020 09 25.
Artículo en Inglés | MEDLINE | ID: mdl-32781010

RESUMEN

Transcranial direct current stimulation (tDCS) over the primary motor cortex (M1) has an antalgic effect on acute experimental pain in healthy volunteers. Many published studies have used online stimulation (i.e., tDCS performed during painful stimulation). On the other hand, daily tDCS sessions have been proposed as a therapy for chronic pain (offline tDCS). In such cases, the therapeutic potential depends on the possible aftereffects of each tDCS session. We set out to investigate whether a single tDCS session before application of a classical experimental pain paradigm (the Cold Pressor Test, CPT) would be capable of modulating physiological measures of anxiety as well as pain perception. tDCS was applied to 30 healthy volunteers, 18-28 years old (mean 18.5), with the anode positioned over either the left M1 or the left dorsolateral prefrontal cortex (l-DLPFC), which has been linked to the affective aspects of experienced pain, including anxiety. All volunteers underwent the CPT procedure before and after a tDCS session. Real 2 mA tDCS sessions for 20 min were compared to sham stimulations. No significant difference was found for any variable after real tDCS sessions when compared to the sham stimulations. This result suggests that effective offline tDCS for chronic pain might have different mechanisms of action. Cumulative effects, functional targeting and the unintended simultaneous stimulation of both M1 and the l-DLPFC are likely responsible for the therapeutic effects of tDCS sessions in the clinical setting.


Asunto(s)
Ansiedad/terapia , Frío , Corteza Motora/fisiología , Manejo del Dolor/métodos , Dolor/fisiopatología , Estimulación Magnética Transcraneal , Adolescente , Adulto , Ansiedad/fisiopatología , Humanos , Masculino , Dimensión del Dolor , Percepción del Dolor/fisiología , Umbral del Dolor/fisiología , Adulto Joven
5.
Front Neurol ; 10: 1145, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31736860

RESUMEN

Autism Spectrum Disorders comprise conditions that may affect cognitive development, motor skills, social interaction, communication, and behavior. This set of functional deficits often results in lack of independence for the diagnosed individuals, and severe distress for patients, families, and caregivers. There is a mounting body of evidence indicating the effectiveness of pure cannabidiol (CBD) and CBD-enriched Cannabis sativa extract (CE) for the treatment of autistic symptoms in refractory epilepsy patients. There is also increasing data support for the hypothesis that non-epileptic autism shares underlying etiological mechanisms with epilepsy. Here we report an observational study with a cohort of 18 autistic patients undergoing treatment with compassionate use of standardized CBD-enriched CE (with a CBD to THC ratio of 75/1). Among the 15 patients who adhered to the treatment (10 non-epileptic and five epileptic) only one patient showed lack of improvement in autistic symptoms. Due to adverse effects, three patients discontinued CE use before 1 month. After 6-9 months of treatment, most patients, including epileptic and non-epileptic, showed some level of improvement in more than one of the eight symptom categories evaluated: Attention Deficit/Hyperactivity Disorder; Behavioral Disorders; Motor Deficits; Autonomy Deficits; Communication and Social Interaction Deficits; Cognitive Deficits; Sleep Disorders and Seizures, with very infrequent and mild adverse effects. The strongest improvements were reported for Seizures, Attention Deficit/Hyperactivity Disorder, Sleep Disorders, and Communication and Social Interaction Deficits. This was especially true for the 10 non-epileptic patients, nine of which presented improvement equal to or above 30% in at least one of the eight categories, six presented improvement of 30% or more in at least two categories and four presented improvement equal to or above 30% in at least four symptom categories. Ten out of the 15 patients were using other medicines, and nine of these were able to keep the improvements even after reducing or withdrawing other medications. The results reported here are very promising and indicate that CBD-enriched CE may ameliorate multiple ASD symptoms even in non-epileptic patients, with substantial increase in life quality for both ASD patients and caretakers.

6.
Cuad. psicol. deporte ; 23(2): 90-105, abril 2023. tab, ilus
Artículo en Español | IBECS (España) | ID: ibc-219715

RESUMEN

En este trabajo presentamos una versión traducida y adaptada del Sport Emotion Questionnaire (SEQ) en portugués brasileño, además de explorar sus características psicométricas. En el Estudio 1 se elaboró la versión brasileña del SEQ (SEQ-BR) de acuerdo con las directrices del proceso de adaptación transcultural, se evaluó la validez de contenido y el acuerdo entre evaluadores. La concordancia entre los evaluadores fue casi excelente (0.77 £ Kappa £ 0.89) y el instrumento se consideró válido desde el punto de vista de su contenido en cuanto a claridad (CVCt = 0.91) y pertinencia (CVCt = 0.93). En el Estudio 2, 895 atletas brasileños de diferentes deportes respondieron al SEQ-BR durante competiciones nacionales e internacionales. Se realizaron análisis factoriales para explorar y confirmar la estructura factorial del SEQ-BR. La estructura con cinco factores presentó un ajuste satisfactorio [χ2 (199) = 395.59; χ2/gl = 1.99; CFI = 0.98; TLI = 0.98; GFI = 0.98; RMSEA = 0.033], además de invarianza factorial entre grupos y consistencia interna adecuada en todos los factores (0.78 £ ω £ 0.85). Teniendo en cuenta lo anterior, el SEQ-BR presenta adecuación en cuanto a la validación del contenido y características psicométricas satisfactorias, proporcionando un instrumento estable, consistente y fiable para medir las emociones precompetitivas en atletas brasileños. (AU)


Neste trabalho apresentamos uma versão traduzida e adaptada doSport Emotion Questionnaire(SEQ) para o Português brasileiro, e exploramossuas características psicométricas. No Estudo 1 foi produzida a versão brasileira do SEQ (SEQ-BR)de acordo com as diretrizes para o processo de adaptação transcultural, eavaliadas a validade de conteúdo e a concordância entre os juízes. O julgamento quanto a concordância entre os juízes foi quase excelente (0.77£Kappa£0.89) e o instrumento foi considerado válido do ponto de vista do seu conteúdo quanto a clareza (CVCt= 0.91) e pertinência (CVCt= 0.93). No Estudo 2, 895 atletas brasileiros de diferentes modalidades esportivas responderam o SEQ-BR durante competições nacionais e internacionais. As análises fatoriais foram realizadas para explorar e confirmar a estrutura fatorial do SEQ-BR. Aestrutura com cinco fatores apresentou um ajuste satisfatório [χ2(199) = 395.59; χ2/gl = 1.99; CFI = 0.98;TLI = 0.98;GFI = 0.98;RMSEA = 0.033], além de invariância fatorial entre grupos e consistência interna adequada em todos os fatores (0.78£ω£0.85). Diante do exposto, o SEQ-BR apresenta adequação quanto à validação do conteúdo e características psicométricas satisfatórias, fornecendo um instrumento estável, consistente e confiável para mensurar emoções pré-competitivas em atletas brasileiros. (AU)


Here we present an adapted version oftheSport Emotion Questionnaire (SEQ)translated to Brazilian Portuguese, and exploreits psychometric characteristics. In Study 1, the Brazilian version of the SEQ (SEQ-BR) was produced according to the guidelines for the cross-cultural adaptation process, and the content validity and inter-rater agreement were evaluated. The agreement was almost excellent between judges (0.77£Kappa£0.89),and the instrument was considered valid from thecontent viewpoint, regarding clarity (CVCt= 0.91) and relevance (CVCt= 0.93). In Study 2, 895 Brazilian athletes from different types of sports answered the SEQ-BR during national and international competitions. Factor analysis were performed to exploreand confirm the factor structure of the SEQ-BR.The structure composed offive factors [χ2(199) = 395.59;χ2/df = 1.99; CFI = 0.98;TLI = 0.98;GFI = 0.98;RMSEA = 0.033], in addition to factorial invariance between groups and adequate internal consistency in all factors (0,78£ω£0,85). The SEQ-BR presents adequacy as to content validity,and satisfactory psychometric characteristics, providing a stable, consistent, and reliable instrument tomeasure pre-competitive emotions in Brazilian athletes. (AU)


Asunto(s)
Humanos , Psicometría , Emociones , Deportes , Psicología del Deporte , Brasil , Encuestas y Cuestionarios
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