Research progress of brain-computer interface application paradigms based on rapid serial visual presentation / 生物医学工程学杂志

Rapid serial visual presentation (RSVP) is a type of psychological visual stimulation experimental paradigm that requires participants to identify target stimuli presented continuously in a stream of stimuli composed of numbers, letters, words, images, and so on at the same spatial location, allowing them to discern a large amount of information in a short period of time. The RSVP-based brain-computer interface (BCI) can not only be widely used in scenarios such as assistive interaction and information reading, but also has the advantages of stability and high efficiency, which has become one of the common techniques for human-machine intelligence fusion. In recent years, brain-controlled spellers, image recognition and mind games are the most popular fields of RSVP-BCI research. Therefore, aiming to provide reference and new ideas for RSVP-BCI related research, this paper reviewed the paradigm design and system performance optimization of RSVP-BCI in these three fields. It also looks ahead to its potential applications in cutting-edge fields such as entertainment, clinical medicine, and special military operations.

Human detection and motion recovery based on monocular vision / Detecção humana e recuperação de movimento com base na visão monocular / Detección humana y recuperación de movimiento basada en visión monocular

ABSTRACT Objective: Provides interactive games and human animation real motion data and technical options. Therefore, how to complete the position, attitude detection, and motion recovery under monocular vision has become an important research direction. Methods: This paper improves the part-based human detection algorithm and uses the AdaBoost multi-instance learning algorithm to train the part detector. Results: The results show that obtaining blood pressure waveform based on monocular vision pulse wave is feasible and has generalization. Conclusions: The results show the feasibility and accuracy of the gait motion detection, motion recovery and analysis system for human lower limbs based on monocular vision. Level of evidence II; Therapeutic studies - investigation of treatment results.

RESUMO Objetivo: Fornece jogos interativos e dados de movimento real de animação humana e opções técnicas. Portanto, como completar a posição, detecção de atitude e recuperação de movimento sob visão monocular tornou-se uma importante direção de pesquisa. Métodos: este artigo aprimora o algoritmo de detecção humana baseado em partes e usa o algoritmo de aprendizado de múltiplas instâncias AdaBoost para treinar o detector de partes. Resultados: Os resultados mostram que o método de obtenção da forma de onda da pressão arterial com base na onda de pulso de visão monocular é viável e se pode generalizar. Conclusões: Os resultados mostram a viabilidade e precisão do sistema de detecção, recuperação e análise do movimento da marcha para membros inferiores humanos com base na visão monocular. Nível de evidência II; Estudos terapêuticos- investigação dos resultados do tratamento.

RESUMEN Objetivo: Proporciona juegos interactivos y animación humana, datos de movimiento real y opciones técnicas. Por lo tanto, cómo completar la posición, la detección de actitud y la recuperación de movimiento bajo visión monocular se ha convertido en una importante dirección de investigación. Métodos: este documento mejora el algoritmo de detección humana basado en piezas y utiliza el algoritmo de aprendizaje de instancias múltiples AdaBoost para entrenar el detector de piezas. Resultados: Los resultados muestran que el método de obtención de la forma de onda de la presión arterial basado en la onda de pulso de visión monocular es factible y se puede generalizar. Conclusiones: Los resultados muestran la viabilidad y precisión del sistema de detección, recuperación y análisis del movimiento de la marcha para miembros inferiores humanos basado en visión monocular. Nivel de evidencia II; Estudios terapéuticos- investigación de los resultados del tratamiento.

Brain stimulation used as biofeedback in neuronal activation of the temporal lobe area in autistic children / Estimulação cerebral usada como biofeedback na ativação neural do lobo temporal em crianças autistas

ABSTRACT This study focused upon the functional capacity of mirror neurons in autistic children. 30 individuals, 10 carriers of the autistic syndrome (GCA), 10 with intellectual impairments (GDI), and 10 non-autistics (GCN) had registered eletroencephalogram from the brain area theoretically related to mirror neurons. Data collection procedure occurred prior to brain stimulation and after the stimulation session. During the second session, participants had to alternately process figures evoking neutral, happy, and/or sorrowful feelings. Results proved that, for all groups, the stimulation process in fact produced additional activation in the neural area under study. The level of activation was related to the format of emotional stimuli and the likelihood of boosting such stimuli. Since the increase of activation occurred in a model similar to the one observed for the control group, we may suggest that the difficulty people with autism have at expressing emotions is not due to nonexistence of mirror neurons.

RESUMO O estudo verificou a capacidade funcional dos neurônios-espelho em crianças autistas. 30 indivíduos, sendo 10 portadores da síndrome autista (GCA), 10 com deficiência intelectual (GDI), e 10 não-autistas (GCN) tiveram registrado o eletroencefalograma da área do cérebro relacionada teoricamente com os neurônios espelho. O procedimento de coleta de dados ocorreu antes e após uma sessão de estimulação cerebral. Durante a segunda coleta de dados, os participantes tiveram de processar alternadamente figuras evocando sentimentos neutros, felizes e tristes. Os resultados provaram que, para todos os grupos, o processo de estimulação de fato produziu ativação adicional na área neural em estudo. O nível de ativação foi relacionada com o formato dos estímulos emocionais. Uma vez que o aumento da ativação ocorreu em um modelo semelhante ao observado para o grupo controle, pode-se sugerir que as pessoas com autismo têm dificuldade em expressar emoções não devido à inexistência de neurônios-espelho.

Vestibular rehabilitation with visual stimuli in peripheral vestibular disorders / Reabilitação vestibular com estímulos visuais nas vestibulopatias periféricas

ABSTRACT INTRODUCTION: Visual stimuli can induce vestibular adaptation and recovery of body balance. OBJECTIVE: To verify the effect of visual stimuli by digital images on vestibular and body balance rehabilitation of peripheral vestibular disorders. METHODS: Clinical, randomized, prospective study. Forty patients aged between 23 and 63 years with chronic peripheral vestibular disorders underwent 12 sessions of rehabilitation with visual stimuli using digital video disk (DVD) (experimental group) or Cawthorne-Cooksey exercises (control group). The Dizziness Handicap Inventory (DHI), dizziness analog scale, and the sensitized Romberg static balance and one-leg stance tests were applied before and after the intervention. RESULTS: Before and after the intervention, there was no difference between the experimental and control groups (p > 0.005) regarding the findings of DHI, dizziness analog scale, and static balance tests. After the intervention, the experimental and control groups showed lower values (p < 0.05) in the DHI and the dizziness analog scale, and higher values (p < 0.05) in the static balance tests in some of the assessed conditions. CONCLUSION: The inclusion of visual stimuli by digital images on vestibular and body balance rehabilitation is effective in reducing dizziness and improving quality of life and postural control in individuals with peripheral vestibular disorders.

RESUMO INTRODUÇÃO: Estímulos visuais podem induzir a adaptação vestibular e recuperar o equilíbrio corporal. OBJETIVO: Verificar o efeito de estímulos visuais por imagens digitais na reabilitação do equilíbrio corporal de vestibulopatias periféricas. MÉTODO: Estudo clínico, randomizado, prospectivo. Quarenta pacientes com vestibulopatia periférica crônica e idade entre 23 e 63 anos foram submetidos à 12 sessões de reabilitação com estímulos visuais em DVD (grupo experimental) ou aos exercícios de Cawthorne-Cooksey (grupo controle). Dizziness Handicap Inventory (DHI), escala visual analógica de tontura e testes de equilíbrio estático de Romberg sensibilizado e de apoio unipodal foram aplicados antes e após a intervenção. RESULTADOS: Antes e após a intervenção, não houve diferença entre os grupos experimental e controle (p > 0,005) no DHI, escala visual analógica e testes de equilíbrio estático. Após a intervenção, o grupo experimental e o controle apresentaram valores menores (p < 0,05) do DHI e da escala visual analógica de tontura e valores maiores (p < 0,05) nos testes de equilíbrio estático em algumas condições avaliadas. CONCLUSÃO: A inclusão de estímulos visuais por imagens digitais na reabilitação do equilíbrio corporal é eficaz na redução da tontura, na melhora da qualidade de vida e do controle postural de vestibulopatias periféricas.

Visual evoked potentials show strong positive association with intracranial pressure in patients with cryptococcal meningitis / Potenciais evocados visuais mostram correlação positiva forte com a pressão intracraniana em pacientes com meningite criptocócica

Objective : To verify the relationship between intracranial pressure and flash visual evoked potentials (F-VEP) in patients with cryptococcal meningitis. Method The sample included adults diagnosed with cryptococcal meningitis admitted at a reference hospital for infectious diseases. The patients were subjected to F-VEP tests shortly before lumbar puncture. The Pearson’s linear correlation coefficient was calculated and the linear regression analysis was performed. Results : Eighteen individuals were subjected to a total of 69 lumbar punctures preceded by F-VEP tests. At the first lumbar puncture performed in each patient, N2 latency exhibited a strong positive correlation with intracranial pressure (r = 0.83; CI = 0.60 - 0.94; p < 0.0001). The direction of this relationship was maintained in subsequent punctures. Conclusion : The intracranial pressure measured by spinal tap manometry showed strong positive association with the N2 latency F-VEP in patients with cryptococcal meningitis. .

Objetivo : Verificar a relação entre pressão intracraniana e potencial evocado visual por flash (PEV-F) em pacientes com meningite criptocócica. Método A amostra incluiu pacientes admitidos em um hospital de referência para doenças infecciosas. Realizou-se PEV-F antes de cada punção lombar. Calculou-se o coeficiente de correlação de Pearson e a equação de regressão linear entre as variáveis latência N2 e pressão intracraniana inferida através de raquimanometria. Resultados Dezoito pacientes foram submetidos a um total de 69 punções lombares. A latência N2 mostrou correlação positiva forte com a pressão de abertura verificada na primeira punção lombar a que cada paciente foi submetido (r = 0,83; IC = 0,60 – 0,94; p < 0,0001). A positividade da correlação foi mantida nas aferições subsequentes. Conclusão Houve associação positiva forte entre a latência N2 do PEV-F e pressão intracraniana em pacientes com meningite criptocócica. .

Estado nutricional de vitaminas A e D em crianças participantes de programa de suplementação alimentar / Vitamin A and D status among child participants in a food supplementation program / Concentraciones séricas de vitaminas A y D en niños del programa de distribución de leche fortificada

Foram avaliados as concentrações séricas de vitaminas A e D e os fatores associados em crianças beneficiárias de programa de distribuição de leite fortificado, sendo utilizados modelos de regressão linear múltiplos com seleção hierárquica de variáveis independentes (condição sociodemográfica, de saúde, alimentação, amamentação, consumo do leite fortificado, exposição solar, antropometria, retinol e calcidiol séricos). Foram consideradas insuficiência e deficiência de vitamina A e de vitamina D as concentrações séricas < 1,05µmol/L, 0,70µmo/L, 30ng/mL e 20ng/mL, respectivamente. Houve inadequação do consumo alimentar de vitaminas A e D. As prevalências de insuficiência e deficiência de vitamina A e de vitamina D foram 19%, 6%, 82% e 58%, respectivamente. Os fatores associados às menores concentrações séricas de vitamina A foram: amamentação materna exclusiva < 120 dias, ausência de trabalho materno combinada com menor escolaridade materna, maior número de pessoas que consomem leite fortificado no domicílio e menor vitamina D sérica. Para a vitamina D, foram: menor exposição ao sol e menor vitamina A sérica. Ações de educação nutricional são necessárias para melhorar a situação nutricional dessas crianças.

Vitamin A and D serum concentrations and risk factors for their deficiencies were investigated in children participating in a government-sponsored fortified milk program. The study used multivariate linear regression analysis with hierarchical selection of independent variables: socio-demographic conditions, children's health, food consumption, breastfeeding, fortified milk, exposure to sunlight, anthropometric measurements, and serum concentration of retinol and 25(OH)D. Vitamin A and vitamin D insufficiency and deficiency values were defined as < 1.05µmol/L, < 0.7µmol/L, < 30ng/mL, and < 20ng/mL, respectively. Vitamin A and D intake was inadequate. Prevalence rates for vitamin A and vitamin D insufficiency and deficiency were 19%, 6%, 82%, and 58%, respectively. Factors associated with low serum vitamin A were exclusive breastfeeding for less than 120 days, low maternal schooling, maternal unemployment, more consumers of fortified milk in the family, and low serum vitamin D. Factors associated with vitamin D deficiency were low exposure to sunlight and low serum vitamin A. Nutritional education is needed to improve children's nutritional status.

Se evaluaron las concentraciones séricas de vitaminas A y D y factores asociados en niños que se benefician del programa de distribución de leche fortificada. Se utilizaron múltiples modelos de regresión lineal, con una selección jerárquica de las variables independientes (estatus sociodemográfico, salud, alimentación, lactancia materna, consumo de leche fortificada, exposición al sol, medidas antropométricas, retinol y calcidiol séricos). Para la insuficiencia y deficiencia de vitamina A y vitamina D, se adoptaron concentraciones séricas < 1,05µmol/L, < 0,70µmol/L, < 30ng/mL, < 20ng/mL, respectivamente. La inadecuación del consumo de alimentos para vitamina A y vitamina D fue de un 40% y 100%, respectivamente. La prevalencia de insuficiencia y la deficiencia de vitamina A y vitamina D fue de un 19%, 6%, 82% y 58%, respectivamente. Los factores asociados más pequeños de vitamina A sérica fueron: lactancia exclusiva < 120 días, ausencia de empleo de la madre, combinada con una baja educación materna y menor vitamina D sérica. Para la vitamina D fueron: menor exposición al sol y menor vitamina A sérica. Las acciones de educación nutricional son necesarias para mejorar la situación nutricional de estos niños.

Differential effects of aging on spatial contrast sensitivity to linear and polar sine-wave gratings

Changes in visual function beyond high-contrast acuity are known to take place during normal aging. We determined whether sensitivity to linear sine-wave gratings and to an elementary stimulus preferentially processed in extrastriate areas could be distinctively affected by aging. We measured spatial contrast sensitivity twice for concentric polar (Bessel) and vertical linear gratings of 0.6, 2.5, 5, and 20 cycles per degree (cpd) in two age groups (20-30 and 60-70 years). All participants were free of identifiable ocular disease and had normal or corrected-to-normal visual acuity. Participants were more sensitive to Cartesian than to polar gratings in all frequencies tested, and the younger adult group was more sensitive to all stimuli tested. Significant differences between sensitivities of the two groups were found for linear (only 20 cpd; P<0.01) and polar gratings (all frequencies tested; P<0.01). The young adult group was significantly more sensitive to linear than to circular gratings in the 20 cpd frequency. The older adult group was significantly more sensitive to linear than to circular gratings in all spatial frequencies, except in the 20 cpd frequency. The results suggest that sensitivity to the two kinds of stimuli is affected differently by aging. We suggest that neural changes in the aging brain are important determinants of this difference and discuss the results according to current models of human aging.

Facilitatory effects of an auditory warning stimulus in a visual location identification task and a visual shape identification task

The occurrence of a weak auditory warning stimulus increases the speed of the response to a subsequent visual target stimulus that must be identified. This facilitatory effect has been attributed to the temporal expectancy automatically induced by the warning stimulus. It has not been determined whether this results from a modulation of the stimulus identification process, the response selection process or both. The present study examined these possibilities. A group of 12 young adults performed a reaction time location identification task and another group of 12 young adults performed a reaction time shape identification task. A visual target stimulus was presented 1850 to 2350 ms plus a fixed interval (50, 100, 200, 400, 800, or 1600 ms, depending on the block) after the appearance of a fixation point, on its left or right side, above or below a virtual horizontal line passing through it. In half of the trials, a weak auditory warning stimulus (S1) appeared 50, 100, 200, 400, 800, or 1600 ms (according to the block) before the target stimulus (S2). Twelve trials were run for each condition. The S1 produced a facilitatory effect for the 200, 400, 800, and 1600 ms stimulus onset asynchronies (SOA) in the case of the side stimulus-response (S-R) corresponding condition, and for the 100 and 400 ms SOA in the case of the side S-R non-corresponding condition. Since these two conditions differ mainly by their response selection requirements, it is reasonable to conclude that automatic temporal expectancy influences the response selection process.

NAA and NAAG variation in neuronal activation during visual stimulation

N-acetyl-aspartyl-glutamate (NAAG) and its hydrolysis product N-acetyl-L-aspartate (NAA) are among the most important brain metabolites. NAA is a marker of neuron integrity and viability, while NAAG modulates glutamate release and may have a role in neuroprotection and synaptic plasticity. Investigating on a quantitative basis the role of these metabolites in brain metabolism in vivo by magnetic resonance spectroscopy (MRS) is a major challenge since the main signals of NAA and NAAG largely overlap. This is a preliminary study in which we evaluated NAA and NAAG changes during a visual stimulation experiment using functional MRS. The paradigm used consisted of a rest period (5 min and 20 s), followed by a stimulation period (10 min and 40 s) and another rest period (10 min and 40 s). MRS from 17 healthy subjects were acquired at 3T with TR/TE = 2000/288 ms. Spectra were averaged over subjects and quantified with LCModel. The main outcomes were that NAA concentration decreased by about 20% with the stimulus, while the concentration of NAAG concomitantly increased by about 200%. Such variations fall into models for the energy metabolism underlying neuronal activation that point to NAAG as being responsible for the hyperemic vascular response that causes the BOLD signal. They also agree with the fact that NAAG and NAA are present in the brain at a ratio of about 1:10, and with the fact that the only known metabolic pathway for NAAG synthesis is from NAA and glutamate.

Comparison of the reliability of multifocal visual evoked cortical potentials generated by pattern reversal and pattern pulse stimulation

This study compared the effectiveness of the multifocal visual evoked cortical potentials (mfVEP) elicited by pattern pulse stimulation with that of pattern reversal in producing reliable responses (signal-to-noise ratio >1.359). Participants were 14 healthy subjects. Visual stimulation was obtained using a 60-sector dartboard display consisting of 6 concentric rings presented in either pulse or reversal mode. Each sector, consisting of 16 checks at 99% Michelson contrast and 80 cd/m² mean luminance, was controlled by a binary m-sequence in the time domain. The signal-to-noise ratio was generally larger in the pattern reversal than in the pattern pulse mode. The number of reliable responses was similar in the central sectors for the two stimulation modes. At the periphery, pattern reversal showed a larger number of reliable responses. Pattern pulse stimuli performed similarly to pattern reversal stimuli to generate reliable waveforms in R1 and R2. The advantage of using both protocols to study mfVEP responses is their complementarity: in some patients, reliable waveforms in specific sectors may be obtained with only one of the two methods. The joint analysis of pattern reversal and pattern pulse stimuli increased the rate of reliability for central sectors by 7.14% in R1, 5.35% in R2, 4.76% in R3, 3.57% in R4, 2.97% in R5, and 1.78% in R6. From R1 to R4 the reliability to generate mfVEPs was above 70% when using both protocols. Thus, for a very high reliability and thorough examination of visual performance, it is recommended to use both stimulation protocols.

Influence of cueing on the preparation and execution of untrained and trained complex motor responses

This study investigated the influence of cueing on the performance of untrained and trained complex motor responses. Healthy adults responded to a visual target by performing four sequential movements (complex response) or a single movement (simple response) of their middle finger. A visual cue preceded the target by an interval of 300, 1000, or 2000 ms. In Experiment 1, the complex and simple responses were not previously trained. During the testing session, the complex response pattern varied on a trial-by-trial basis following the indication provided by the visual cue. In Experiment 2, the complex response and the simple response were extensively trained beforehand. During the testing session, the trained complex response pattern was performed in all trials. The latency of the untrained and trained complex responses decreased from the short to the medium and long cue-target intervals. The latency of the complex response was longer than that of the simple response, except in the case of the trained responses and the long cue-target interval. These results suggest that the preparation of untrained complex responses cannot be completed in advance, this being possible, however, for trained complex responses when enough time is available. The duration of the 1st submovement, 1st pause and 2nd submovement of the untrained and the trained complex responses increased from the short to the long cue-target interval, suggesting that there is an increase of online programming of the response possibly related to the degree of certainty about the moment of target appearance.

Visual stimuli and written production of deaf signers / Estímulos visuais e produção escrita de surdos sinalizadores

PURPOSE: To verify the interference of visual stimuli in written production of deaf signers with no complaints regarding reading and writing. METHODS: The research group consisted of 12 students with education between the 4th and 5th grade of elementary school, with severe or profound sensorineural hearing loss, users of LIBRAS and with alphabetical writing level. The evaluation was performed with pictures in a logical sequence and an action picture. The analysis used the communicative competence criteria. RESULTS: There were no differences in the writing production of the subjects for both stimuli. In all texts there was no title and punctuation, verbs were in the infinitive mode, there was lack of cohesive links and inclusion of created words. CONCLUSION: The different visual stimuli did not affect the production of texts.

OBJETIVO: Verificar a interferência de estímulos visuais na escrita de surdos sinalizadores sem queixas de leitura e escrita. MÉTODOS: O grupo de pesquisa foi composto por 12 alunos com escolaridade entre o quarto e o quinto ano do ensino fundamental, com perda neurossensorial de grau severo ou profundo, usuários de Língua Brasileira de Sinais (LIBRAS) e com nível alfabético de escrita. Os sujeitos foram orientados a elaborar um texto para cada estímulo visual apresentado: figuras de sequência lógica e uma figura de ação. A análise foi realizada seguindo-se os critérios das competências comunicativas. RESULTADOS: Não foram observadas diferenças na produção escrita dos sujeitos da pesquisa para ambos os estímulos. Observou-se ausência de título e pontuação, verbos no modo infinitivo, ausência de elos coesivos e inclusão de palavras inventadas. CONCLUSÃO: Os diferentes estímulos visuais não interferem na produção textual dos sujeitos.

Long-term potentiation and long-term depression: a clinical perspective

Long-term potentiation and long-term depression are enduring changes in synaptic strength, induced by specific patterns of synaptic activity, that have received much attention as cellular models of information storage in the central nervous system. Work in a number of brain regions, from the spinal cord to the cerebral cortex, and in many animal species, ranging from invertebrates to humans, has demonstrated a reliable capacity for chemical synapses to undergo lasting changes in efficacy in response to a variety of induction protocols. In addition to their physiological relevance, long-term potentiation and depression may have important clinical applications. A growing insight into the molecular mechanisms underlying these processes, and technological advances in non-invasive manipulation of brain activity, now puts us at the threshold of harnessing long-term potentiation and depression and other forms of synaptic, cellular and circuit plasticity to manipulate synaptic strength in the human nervous system. Drugs may be used to erase or treat pathological synaptic states and non-invasive stimulation devices may be used to artificially induce synaptic plasticity to ameliorate conditions arising from disrupted synaptic drive. These approaches hold promise for the treatment of a variety of neurological conditions, including neuropathic pain, epilepsy, depression, amblyopia, tinnitus and stroke.

Micropropagação e aclimatização de gerânio (Pelargonium graveolens L. ) / Micropropagation and acclimatization of geranium (Pelargonium graveolens L. )

O gerânio (Pelargonium graveolens L.) é uma planta medicinal e aromática nativa do sul da África, cujo óleo essencial é amplamente empregado nas indústrias de perfumaria e cosmético, além de ser usado como terapêutico. Avaliou-se o efeito da luminosidade e dos reguladores de crescimento BAP e ANA na multiplicação in vitro e o uso de diferentes substratos na aclimatização de mudas micropropagadas. Foram avaliadas as concentrações 0; 0,5; 1,0 e 2,0 mg L-1 de BAP, 0; 0,1 e 0,5 mg L-1 de ANA e duas condições de luminosidade (ausência e presença de luz), em esquema fatorial 4x3x2; para a aclimatização foram utilizados quatro substratos, pó de coco + Biosafra® (3-12-6) (12 g L-1) + calcário (1 g L-1) (PCBC); pó de coco + Biosafra® (3-12-6) (12 g L-1) + calcário (1 g L-1) + vermiculita (1:1) (PCBCV 1:1); pó de coco + Biosafra® (3-12-6) (12 g L­-1) + calcário (1 g L-1) + vermiculita (PCBCV 2:1) e vermiculita e adição semanal de sais MS (VS). Para a micropropagação de P. graveolens a utilização de 1,3 mg L-1 de BAP e 0,5 mg L-1 de ANA é eficiente na regeneração direta de plantas de gerânio, sendo a condição de escuro a mais indicada por proporcionar o maior número de brotos por explante. Para a aclimatização das mudas de gerânio, os melhores resultados foram obtidos em mudas aclimatizadas no substrato vermiculita com adição semanal de sais de MS seguido do substrato PCBCV 1:1.

Geranium (Pelargonium graveolens L.) is a medicinal and aromatic plant native to the south of Africa and whose essential oil is widely used by perfume and cosmetic industries, as well as in therapeutics. The effect of luminosity and growth regulators BAP and NAA on in vitro multiplication was evaluated, together with the use of different substrates on the acclimatization of micropropagated seedlings. The evaluated concentrations were 0, 0.5, 1.0 and 2.0 mg L-1 BAP; 0, 0.1 and 0.5 mg L-1 NAA; and two luminosity conditions (absence and presence of light), in a 4 x 3 x 2 factorial arrangement. For acclimatization, four substrates were tested: coconut dust + Biosafra® (3-12-6) (12 g L-1) + limestone (1 g L-1) (CDBL); coconut dust + Biosafra® (3-12-6) (12 g L-1) + limestone (1 g L-1) + vermiculite (1:1) (CDBLV 1:1); coconut dust + Biosafra® (3-12-6) (12 g L-1) + limestone (1 g L-1) + vermiculite (CDBLV 2:1); and vermiculite with weekly addition of MS salts (VS). For P. graveolens micropropagation, the use of 1.3 mg L-1 BAP and 0.5 mg L-1 NAA is efficient for the direct regeneration of geranium plants, and the dark condition is the most suitable since it provides a larger number of shoots per explant. For the acclimatization of geranium seedlings, the best results were obtained with seedlings acclimatized in the substrate vermiculite with weekly addition of MS salts, followed by the substrate CDBLV 1:1.

Seleção de estímulos visuais para o Teste de Associação Implícita para o Transtorno Obsessivo-Compulsivo (TAI-TOC) / Selection of visual stimuli for the Implicit Association Test for the Obsessive-Compulsive Disorder (IAT-OCD)

INTRODUÇÃO: A identificação do viés cognitivo no Transtorno Obsessivo-Compulsivo (TOC) permanece inconclusiva. Uma área de interesse potencial inclui a verificação do processamento visual e desempenho de memória implícita. OBJETIVOS: Selecionar estímulos visuais para inclusão em uma versão do Teste de Associação Implícita (TAI) para o TOC. MÉTODOS: Dezessete pacientes com TOC e 17 controles saudáveis avaliaram 12 estímulos visuais relacionados a diferentes dimensões dos sintomas obsessivo-compulsivos e classificaram os estímulos de acordo com dois critérios: "tipo de impacto" (i.e., positivo, negativo ou neutro) e "grau de impacto" [i.e., 1 (baixo impacto) a 5 (alto impacto)]. Nos testes qui-quadrado e Mann-Whitney, foi utilizado nível de significância de 0.05. RESULTADOS: Pacientes com TOC avaliaram 9 dos 12 estímulos visuais diferente dos controles saudáveis, em pelo menos um dos dois critérios. Discussão: O achado de que as figuras empregadas foram capazes de diferenciar pacientes de controles saudáveis sugere sua inclusão no desenvolvimento de instrumentos de avaliação psicopatológica, como o TAI-TOC.

INTRODUCTION: The identification of cognitive bias in Obsessive-Compulsive Disorder (OCD) remains inconclusive. An area of potential interest includes the examination of visual processing and implicit memory performance. OBJECTIVES: Select visual stimuli to include in a version of the Implicit Association Test (IAT) for OCD. METHODS: Seventeen patients with OCD and 17 healthy controls evaluated 12 visual stimuli related to different dimensions of obsessive-compulsive symptoms and classified the stimuli according to two criteria: "type of impact" (i.e., positive, negative or neutral) and "degree of impact" [i.e., 1 (low impact) to 5 (high impact)]. The chi-square and the Mann-Whitney tests were employed and the level of significance at 0.05. RESULTS: OCD patients evaluated 9 out of the 12 stimuli different from healthy controls in at least one of the two criteria. DISCUSSION: The finding that the figures employed were able to differentiate OCD patients from healthy controls suggests their inclusion in the psychopathological assessment development tools, such as the IAT-OCD.

The Influence of Contrasts on Directional and Spatial Frequency Tuning in Visual Cortex Areas 17/18 of the Cat

PURPOSE: The purpose of this study was to investigate the effects of contrast display exposure on neuronal directional and spatial frequency tuning. Neuronal responses were recorded from ninety-four neurons in cortical areas 17 and 18 in two adult cats. METHODS: A multi-channel microelectrode was implanted in cortical areas 17 and 18 of two paralyzed and anaesthetized cats. Various drifting sinusoidal grating contrast displays were presented to one of the cats' eyes in the visual field. Contour plots based on the neuronal responses to the drifting sinusoidal grating displays using various contrasts (i.e., 0.4, 0.7, and 1.0) and velocities (i.e., 4.6, 13.9, 23.1, 32.3, 41.5, 50.8, and 60.0 deg/sec) were plotted as a function of the spatial frequency and the direction associated with each velocity and contrast used. RESULTS: Five parameters were extracted from these contour plots: 1) optimum response, 2) preferred direction, 3) optimum spatial frequency, 4) directional tuning width, and 5) spatial frequency bandwidth. To determine the optimal velocity, each parameter was plotted against each of the specific display contrasts used, and a 'best fit' line was established. Response amplitudes were dependent on the type of contrast utilized; however, the spatial frequency and directional tuning properties were stable for the cortical neurons assessed. CONCLUSIONS: The results of the presentation of different contrasts on neuronal directional and spatial frequency tuning are consistent with behavioral results when medium and high contrast displays are used.

Clareamento de dentes vitais com a utilização da luz / In-affice dental bleaching oi vital teeth with the use af light

A crescente demanda por um sorriso branco e saudável associada à introdução de novos materiais e técnicas, resultou em uma evolução significativa na Odontologia estética. Dentre os tratamentos mais procurados pelos pacientes, o clareamento de dentes vitais realizado em consultório - também chamado de clareamento assistido - tem sido amplamente utilizado e consiste na utilização de géis de peróxido de carbamida ou hidrogênio em alta concentração. A principal vantagem dessa técnica são os significativos resultados estéticos alcançados em poucas sessões, com curta duração. No entanto, a técnica requer do Cirurgião-Dentista conhecimento técnico-científico e cuidados especiais, não apenas com as estruturas de esmalte e dentina, como também com os tecidos moles da cavidade bucal. Este artigo tem como objetivo abordar aspectos importantes da técnica que auxiliarão o profissional na sua realização em consultório. Serão abordados estudos que descrevem as indicações da técnica, bem como os que discutem os seus benefícios e limitações, apresentando aspectos científicos importantes para a prática clínica.

Within the most requested treatments, in-office dental bleaching has been widely in- dicated and consists on the use of high concentrated carbamide and hydrogen peroxides (25-38%). The main advantage of the technique is the significant esthetic results that can be achieved in few clinical sessions with a short period of exposure of the bleaching agent to the dental surface. However, the in-office bleaching requires from the professional some technical and scientific skills and specific care not only with enamel and dentin structures but also with the surrounding soft tissues. This manuscript aims to address important topics that will help professionals in their day-by-day clinic. Studies related to the in-office technique, its benefits and limitations will be discussed and important scientific information will be highlighted in order to guide the clinical practice.

Emotional declarative memory assessment of patients with mesial temporal lobe epilepsy and patients submitted to mesial temporal lobectomy / Avaliação da memória declarativa emocional em pacientes com epilepsia temporal mesial e pacientes submetidos à lobectomia temporal mesial

Epileptic seizures generate cognitive and behavioral impacts in individuals who suffer from epilepsy. Declarative memory is one of the cognitive functions that can be affected by epileptic seizures. The main objective of this work was to investigate neurocognitive function, especially the emotional working memory of patients with unilateral mesial temporal lobe epilepsy, and that of patients submitted to unilateral mesial temporal lobectomy. A face recognition test that can simultaneously recruit the frontal lobe (working memory) and mesial temporal lobe (emotional memory) was used to investigate emotional working memory. Our findings showed that the epilepsy factor significantly compromised the performance in the emotional memory test. On the other hand, surgical removal of the epileptic focus promoted an improvement in the emotional working memory of these patients, in addition to the significantly decrease in the number of seizures.

Crises epilépticas geram impactos comportamentais e cognitivos em indivíduos que sofrem de epilepsia. Uma das funções cognitivas que pode ser afetada pelas crises epilépticas é a memória declarativa. O objetivo do nosso estudo foi investigar funções cognitivas, especialmente a memória operacional emocional de pacientes com epilepsia temporal mesial unilateral e pacientes submetidos a lobectomia temporal mesial unilateral. Para investigar a memória operacional emocional foi utilizado um teste de reconhecimento de faces que pode recrutar simultaneamente o lobo frontal (memória operacional) e o lobo temporal mesial (memória emocional). Nossos resultados demonstram que o fator epilepsia compromete de forma significativa o desempenho no teste de memória emocional. Por outro lado, a remoção cirúrgica do foco epiléptico promoveu uma melhora na memória emocional desses pacientes, além de diminuir o número de crises.

Reaction time assessment in children with ADHD / Avaliação do tempo de reação em crianças portadoras do transtorno do déficit de atenção/hiperatividade (TDAH)

Attention deficit, impulsivity and hyperactivity are the cardinal features of attention deficit hyperactivity disorder (ADHD) but executive function (EF) disorders, as problems with inhibitory control, working memory and reaction time, besides others EFs, may underlie many of the disturbs associated with the disorder. OBJECTIVE: To examine the reaction time in a computerized test in children with ADHD and normal controls. METHOD: Twenty-three boys (aged 9 to 12) with ADHD diagnosis according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, 2000 (DSM-IV) criteria clinical, without comorbidities, Intelligence Quotient (IQ) >89, never treated with stimulant and fifteen normal controls, age matched were investigated during performance on a voluntary attention psychophysical test. RESULTS: Children with ADHD showed reaction time higher than normal controls. CONCLUSION: A slower reaction time occurred in our patients with ADHD. This findings may be related to problems with the attentional system, that could not maintain an adequate capacity of perceptual input processes and/or in motor output processes, to respond consistently during continuous or repetitive activity.

Déficit de atenção, impulsividade e hiperatividade são os pontos cardinais do transtorno do déficit de atenção/hiperatividade (TDAH), mas as desordens da função executiva (FE) tais como os problemas no controle inibitório, memória operacional e tempo de reação, dentre outras funções executivas (FEs) podem estar subjacentes a muitos distúrbios associados a esta desordem. OBJETIVO: Avaliar o tempo de reação em meninos portadores do TDAH. MÉTODO: Participaram 23 pacientes do sexo masculino, de idade entre 9 a 12 anos de idade, com diagnóstico de TDAH sem co-morbidades, estabelecido segundo os critérios do Diagnostic and Statistical Manual of Mental Disorders Fourth Edition (DSM-IV), com Quoeficiente Intelectual (QI) >89, que não tivessem sido medicados para o TDAH. Grupo controle, seguindo os mesmos critérios em relação ao sexo, idade, QI. O teste utilizado foi o teste psicofísico da atenção voluntária (TPAV). RESULTADOS: Os pacientes do TDAH apresentaram maior tempo de reação na execução do teste em relação aos controles. CONCLUSÃO: O tempo de reação apresentou-se mais lento em nossos pacientes portadores de TDAH. Estes achados podem estar relacionados aos problemas do sistema atencional; este grupo não pôde manter uma adequada capacidade de percepção de dados processados e/ou, em responder regularmente durante atividades contínuas ou repetitivas.

Time-Course Analysis of the Neuroanatomical Correlates of Sexual Arousal Evoked by Erotic Video Stimuli in Healthy Males

OBJECTIVE: To assess the dynamic activations of the key brain areas associated with the time-course of the sexual arousal evoked by visual sexual stimuli in healthy male subjects. MATERIALS AND METHODS: Fourteen right-handed heterosexual male volunteers participated in this study. Alternatively combined rest period and erotic video visual stimulation were used according to the standard block design. In order to illustrate and quantify the spatiotemporal activation patterns of the key brain regions, the activation period was divided into three different stages as the EARLY, MID and LATE stages. RESULTS: For the group result (p < 0.05), when comparing the MID stage with the EARLY stage, a significant increase of the brain activation was observed in the areas that included the inferior frontal gyrus, the supplementary motor area, the hippocampus, the head of the caudate nucleus, the midbrain, the superior occipital gyrus and the fusiform gyrus. At the same time, when comparing the EARLY stage with the MID stage, the putamen, the globus pallidus, the pons, the thalamus, the hypothalamus, the lingual gyrus and the cuneus yielded significantly increased activations. When comparing the LATE stage with the MID stage, all the above mentioned brain regions showed elevated activations except the hippocampus. CONCLUSION: Our results illustrate the spatiotemporal activation patterns of the key brain regions across the three stages of visual sexual arousal.