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1.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(5): 705-710, 2019 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-31631617

RESUMO

Attention can concentrate our mental resources on processing certain interesting objects, which is an important mental behavior and cognitive process. Recognizing attentional states have great significance in improving human's performance and reducing errors. However, it still lacks a direct and standardized way to monitor a person's attentional states. Based on the fact that visual attention can modulate the steady-state visual evoked potential (SSVEP), we designed a go/no-go experimental paradigm with 10 Hz steady state visual stimulation in background to investigate the separability of SSVEP features modulated by different visual attentional states. The experiment recorded the EEG signals of 15 postgraduate volunteers under high and low visual attentional states. High and low visual attentional states are determined by behavioral responses. We analyzed the differences of SSVEP signals between the high and low attentional levels, and applied classification algorithms to recognize such differences. Results showed that the discriminant canonical pattern matching (DCPM) algorithm performed better compared with the linear discrimination analysis (LDA) algorithm and the canonical correlation analysis (CCA) algorithm, which achieved up to 76% in accuracy. Our results show that the SSVEP features modulated by different visual attentional states are separable, which provides a new way to monitor visual attentional states.


Assuntos
Atenção , Potenciais Evocados Visuais , Estimulação Luminosa , Algoritmos , Eletroencefalografia , Humanos
2.
Codas ; 31(4): e20170241, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31483038

RESUMO

PURPOSE: This study investigated the effects of two levels of noise on the performance of young students of three educational levels and tested their ability to maintain attentional focus in reading and writing tasks. METHODS: 162 school children in the third, fourth and fifth grades were placed in three groups according to their educational level: Control Group (CG), Experimental Group A (GEA) and Experimental Group B (GEB). All groups were submitted to a Sustained Attention Test, Reading Assessment and Isolated Words Test and Writing Dictation Sub-test (part of the International Dyslexia Test). The GEA and GEB performed the tests in a noisy environment: 20dB and 40dB, respectively. The CG was assessed in the usual school environmental noise at the same time of the day. The data was submitted to an ANOVA, the Kruskal-Wallis test and Spearman correlation test. RESULTS: The higher the score on the Sustained Attention Test, the shorter the time spent reading and fewer errors in the dictation task. There were no differences across the three grades within the GEA (lower levels of noise) with regard to the effect of noise on attention and in the reading and writing task performance. The higher levels of noise for the GEB, however, decreased the attention levels, therefore increasing mistakes on the dictation test. Comparing the performance across educational levels on the reading tasks, the fourth grade presented decreased reading time, while the third and fifth grades spent more time reading. CONCLUSION: Auditory interference can influence the ability to focus attention as well as worsen performance in reading and writing tasks at more intense noise levels.


Assuntos
Atenção/fisiologia , Ruído , Leitura , Análise e Desempenho de Tarefas , Redação , Análise de Variância , Criança , Humanos , Estatísticas não Paramétricas , Estudantes
3.
Brain Nerve ; 71(9): 993-1002, 2019 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-31506401

RESUMO

Joint attention behaviors involve sharing attention with others to an object or event by means of eye-gazing or pointing, which form the common basis for communication. There are two types of these behaviors: responding to joint attention (RJA) and initiating joint attention (IJA). RJA is the ability to follow the gaze of others, suggesting reception of a social signal from others; IJA is the ability to voluntarily direct the attention of others, to share the experience of an object or event, suggesting transmission of a social signal to others. Infants experience these roles (as signal receiver and signal transmitter) throughout the first year of life and learn social cognitive skills. Recent neuroimaging studies indicate that joint attention is supported by widely distributed neural systems with nodes in the dorsomedial prefrontal cortex, the orbitofrontal cortex and insula, the anterior and posterior cingulate cortex, the superior temporal cortex, the precuneus and parietal cortex, and the amygdala and striatum.


Assuntos
Atenção , Encéfalo/fisiologia , Comportamento Social , Córtex Cerebral , Humanos , Lactente , Lobo Parietal , Córtex Pré-Frontal , Lobo Temporal
5.
Psychiatr Danub ; 31(Suppl 3): 318-323, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31488747

RESUMO

INTRODUCTION: Eye movement pathology can assist in the identification, diagnosis and treatment of mental health disorders. Eye-tracking paradigms have been utilized to provide greater ecological validity, and directly capture the detailed sequence of processes in perception and attention, while quantifying classifiers in mood, anxiety, and psychotic disorders. Saccadic eye movements serve as an endophenotype for various mental health disorders. SUBJECTS AND METHODS: Patients suffering from post-concussive syndrome and mental health concerns performed saccadic eye movements that were quantified for amplitude, velocity, latency and accuracy before and after Head-Eye Vestibular Motion therapy (HEVM). RESULTS: HEVM therapy is associated with statistical and substantive significant improvements in mental health and in saccadic metrics. CONCLUSIONS: Oculomotor dysfunction is related to the symptom dimensions of mental health disorders that may be treated with physical rehabilitation modalities. We feel it reasonable to suggest that psychiatrists and others involved in the treatment of mental health disorders quantify eye movements and use them as biomarkers in the evaluation of the outcomes of varied therapies.


Assuntos
Transtornos Mentais/fisiopatologia , Transtornos Mentais/terapia , Movimentos Sacádicos/fisiologia , Atenção/fisiologia , Cabeça/fisiologia , Humanos , Transtornos Mentais/diagnóstico
6.
Nat Neurosci ; 22(10): 1669-1676, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31477898

RESUMO

Visual attention dramatically improves individuals' ability to see and modulates the responses of neurons in every known visual and oculomotor area, but whether such modulations can account for perceptual improvements is unclear. We measured the relationship between populations of visual neurons, oculomotor neurons and behavior during detection and discrimination tasks. We found that neither of the two prominent hypothesized neuronal mechanisms underlying attention (which concern changes in information coding and the way sensory information is read out) provide a satisfying account of the observed behavioral improvements. Instead, our results are more consistent with the hypothesis that attention reshapes the representation of attended stimuli to more effectively influence behavior. Our results suggest a path toward understanding the neural underpinnings of perception and cognition in health and disease by analyzing neuronal responses in ways that are constrained by behavior and interactions between brain areas.


Assuntos
Atenção/fisiologia , Neurônios/fisiologia , Animais , Tomada de Decisões/fisiologia , Discriminação (Psicologia)/fisiologia , Macaca mulatta , Masculino , Neurônios Motores/fisiologia , Rede Nervosa/fisiologia , Desempenho Psicomotor/fisiologia , Psicofísica
8.
Adv Exp Med Biol ; 1155: 821-846, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31468450

RESUMO

Lead (Pb2+) is a developmental neurotoxicant that causes lifelong cognitive dysfunctions. In particular, Pb2+-induced frontoexecutive dysfunctions emerge later in life when the cortex is fully myelinated, thereby permitting the ability to assess the extent to which Pb2+ has developmentally impacted higher order cognitive and behavioral systems. The present study evaluated the effects of developmental Pb2+-exposure (150 ppm lead acetate in the drinking water) in Long Evans Hooded rats through the Attention Set-Shift Test (ASST) between postnatal days (PND) 60-90. Treatment groups were comprised of Control (0 ppm), Perinatal (150 ppm), and Perinatal+Taurine (150 ppm + 0.05% Taurine in the drinking water) rats (N = 36; n = 6 per treatment group for each sex). Frontoexecutive functions were evaluated based on trials-to-criterion (TTC) and errors-to-criterion (ETC) measures for simple and complex discriminations (SD & CD), intradimensional and extradimensional shifts (ID & ED), as well as reversals (Rev) of the CD, I-, and ED stages, respectively. Post-testing, the prelimbic (PrL), infralimbic (IL), orbital ventral frontal (OV), orbital ventro-lateral (OVL), and hippocampal (HP) brain regions were extracted and processed through Liquid Chromatography/Mass Spectrophotometry (LC/MS) for determining the GABA and Taurine ratios relative to Glutamate, Dopamine, Norepinephrine, Epinephrine, and Serotonin. The ASST data revealed that Perinatal rats are negatively impacted by developmental Pb2+-exposures evidenced by increased TTC and ETC to learn the SD, ID, and ID-Rev with unique sex-based differences in frontoexecutive dysfunctions. Moreover, Perinatal+Taurine co-treated rats exhibited a recovery of the frontoexecutive dysfunctions observed in Perinatal rats to levels equivalent to Control rats across both sexes. The LC/MS data revealed altered brain sub-region specific patterns across the PrL, IL, OV, OVL, and HP in response to developmental Pb2+-exposure that produced an altered neurochemical signaling profile in a sex-dependent manner, which may underlie the observed frontoexecutive dysfunctions, cognitive inflexibility, and associated motivation deficits. When taurine co-treatment was administered concurrently for the duration of developmental Pb2+-exposure, the observed frontoexecutive dysfunctions were significantly reduced in both ASST task performance and neurochemical ratios that were comparable to Control levels for both sexes. Altogether, the data suggest that taurine co-treatment may facilitate neuroprotection, mitigate neurotransmitter excitability balancing, and perhaps ameliorate against neurotoxicant exposures in early development as a potential psychopharmacotherapy.


Assuntos
Atenção , Função Executiva , Chumbo/efeitos adversos , Exposição Materna/efeitos adversos , Taurina/farmacologia , Animais , Feminino , Aprendizagem , Masculino , Fármacos Neuroprotetores/farmacologia , Gravidez , Ratos , Ratos Long-Evans
9.
Stud Health Technol Inform ; 264: 457-461, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31437965

RESUMO

Cluster analysis aims at separating patients into phenotypically heterogenous groups and defining therapeutically homogeneous patient subclasses. It is an important approach in data-driven disease classification and subtyping. Acute coronary syndrome (ACS) is a syndrome due to sudden decrease of coronary artery blood flow, where disease classification would help to inform therapeutic strategies and provide prognostic insights. Here we conducted an outcome-driven cluster analysis of ACS patients, which jointly considers treatment and patient outcome as indicators for patient state. Multi-task neural network with attention was used as a modeling framework, including learning of the patient state, cluster analysis, and feature importance profiling. Seven patient clusters were discovered. The clusters have different characteristics, as well as different risk profiles to the outcome of in-hospital major adverse cardiac events. The results demonstrate cluster analysis using outcome-driven multi-task neural network as promising for patient classification and subtyping.


Assuntos
Síndrome Coronariana Aguda , Atenção , Análise por Conglomerados , Humanos , Prognóstico
10.
Postgrad Med ; 131(7): 509-522, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31422718

RESUMO

Objectives: Visual hallucinations (VH) are common in Lewy body disease (LBD), and have been associated with cognitive and structural brain alterations. Evidence so far concerns mainly Parkinson's disease (PD), but little is known about symptom-specific pathophysiological mechanisms across the LBD spectrum, especially related to the presence of dementia. The aim of the present pilot study was to investigate the neuroanatomical, and neuropsychological characteristics related to VH in two forms of LBD, namely dementia with Lewy bodies (DLB) and PD without dementia. Methods: Whole brain voxel-based morphometry (VBM) analyses on 3D MRI acquired structural brain scans, and neuropsychological testing were performed on 28 clinically diagnosed DLB (11 with VH, 17 NVH), and 24 PD (9 with VH, and 15 NVH) patients. In order to assess differences in gray matter (GM) regional volumes, and cognitive performance, hallucinating patients for each group were compared with corresponding non-hallucinating ones. Results: DLB patients with VH presented significantly worse visual attention deficits compared to those without, which persisted even when controlling for visual perception. Whole brain VBM analysis revealed decreased GM volume in DLB with VH in the right superior and medial frontal gyri, putamen, caudate nucleus and insula. Subcortical regional volumes were also significantly associated with visual attention performance. Hallucinating PD patients, instead, presented more severe executive dysfunction, but VBM showed no volumetric differences between the two PD subgroups. Post hoc region of interest analyses revealed striatal GM loss in PD with VH. Conclusion: Frontal and striatal GM atrophy may contribute to the emergence of VH in DLB, which may be fostered by the more severe attention deficits. Striatal GM loss and executive dysfunction, instead, appeared to underlie VH in PD without dementia.


Assuntos
Núcleo Caudado/diagnóstico por imagem , Lobo Frontal/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Alucinações/diagnóstico por imagem , Doença por Corpos de Lewy/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Putamen/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Atenção , Estudos de Casos e Controles , Núcleo Caudado/patologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Feminino , Lobo Frontal/patologia , Substância Cinzenta/patologia , Alucinações/psicologia , Humanos , Doença por Corpos de Lewy/psicologia , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tamanho do Órgão , Doença de Parkinson/psicologia , Putamen/patologia , Percepção Visual
11.
Zool Res ; 40(5): 394-403, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31393096

RESUMO

Information flow between the prefrontal and visual cortices is critical for visual behaviors such as visual search. To investigate its mechanisms, we simultaneously recorded spike and local field potential (LFP) signals in the frontal eye field (FEF) and area V4 while monkeys performed a free-gaze visual search task. During free-gaze search, spike-LFP coherence between FEF and V4 was enhanced in the theta rhythm (4-8 Hz) but suppressed in the alpha rhythm (8-13 Hz). Cross-frequency couplings during the Cue period before the search phase were related to monkey performance, with higher FEF theta-V4 gamma coupling and lower FEF alpha-V4 gamma coupling associated with faster search. Finally, feature-based attention during search enhanced spike-LFP coherence between FEF and V4 in the gamma and beta rhythms, whereas overt spatial attention reduced coherence at frequencies up to 30 Hz. These results suggest that oscillatory coupling may play an important role in mediating interactions between the prefrontal and visual cortices during visual search.


Assuntos
Atenção , Lobo Frontal/fisiologia , Macaca mulatta/fisiologia , Córtex Visual/fisiologia , Potenciais de Ação , Animais , Masculino
12.
Neuron ; 103(3): 353-355, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31394057

RESUMO

The prefrontal cortex modifies the sensory system to focus attention. In this issue of Neuron, Nakajima et al. (2019) fill the gap between the prefrontal cortex and the sensory system with an overlooked basal ganglia pathway.


Assuntos
Gânglios da Base , Córtex Pré-Frontal , Atenção , Filtro Sensorial , Tálamo
13.
Psychol Aging ; 34(6): 780-790, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31380666

RESUMO

An influential account of normative aging effects on reading holds that older adults make greater use of contextual predictability to facilitate word identification. However, supporting evidence is scarce. Accordingly, we used measures of eye movements to experimentally investigate age differences in word predictability effects in Chinese reading, as this nonalphabetic language has characteristics that may promote such effects. Word-skipping rates were higher and reading times lower for more highly predictable words for both age groups. Effects of word predictability on word skipping did not differ across the 2 adult age groups. However, word predictability effects in reading time measures sensitive to both lexical identification (i.e., gaze duration) and contextual integration (i.e., regression-path reading times) were larger for the older than younger adults. Our findings therefore reveal that older Chinese readers make greater use of a word's predictability to facilitate both its lexical identification and integration with the prior sentence context. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Envelhecimento/fisiologia , Atenção/fisiologia , Envelhecimento Cognitivo/psicologia , Movimentos Oculares/fisiologia , Linguagem , Leitura , Adolescente , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Grupo com Ancestrais do Continente Asiático , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Percepção Visual/fisiologia , Adulto Jovem
14.
Psychol Aging ; 34(6): 805-820, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31414857

RESUMO

In hybrid foraging tasks, observers search visual displays, so called patches, for multiple instances of any of several types of targets with the goal of collecting targets as quickly as possible. Here, targets were photorealistic objects. Younger and older adults collected targets by mouse clicks. They could move to the next patch whenever they decided to do so. The number of targets held in memory varied between 8 and 64 objects, and the number of items (targets and distractors) in the patches varied between 60 and 105 objects. Older adults foraged somewhat less efficiently than younger adults due to a more exploitative search strategy. When target items became depleted in a patch and search slowed down, younger adults acted according to the optimal foraging theory and moved on to the next patch when the instantaneous rate of collection was close to their average rate of collection. Older adults, by contrast, were more likely to stay longer and spend time searching for the last few targets. Within a patch, both younger and older adults tended to collect the same type of target in "runs." This behavior is more efficient than continual switching between target types. Furthermore, after correction for general age-related slowing, RT × set size functions revealed largely preserved attention and memory functions in older age. Hybrid foraging tasks share features with important real-world search tasks. Differences between younger and older observers on this task may therefore help to explain age differences in many complex search tasks of daily life. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Envelhecimento , Atenção/fisiologia , Envelhecimento Cognitivo , Percepção de Forma/fisiologia , Memória de Curto Prazo/fisiologia , Memória , Reconhecimento Visual de Modelos/fisiologia , Percepção Visual/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Vida , Masculino , Pessoa de Meia-Idade , Motivação , Estimulação Luminosa/métodos , Tempo de Reação , Adulto Jovem
15.
Nature ; 571(7763): 43-44, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31263260
17.
Medicine (Baltimore) ; 98(26): e16114, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31261527

RESUMO

OBJECTIVE: Cognitive impairment subjects exhibit high cortisol levels that are associated with low brain activity, but negative emotions with high cortisol are associated with high brain activity and reduced cognition. Emotion regulation, glucocorticoid hormones, and brain activity all interact with cognitive impairment. Therefore, we aimed to investigate cognitive impairment differences related to sex, morning salivary cortisol, emotion regulation, and brain activity in elderly people. METHODS: A total of 64 participants (19 males and 45 females) were tested by the Montreal cognitive assessment. Next, morning saliva was collected from each participant and analyzed by enzyme-linked immunosorbent assay, and the brain activity of the participants was subsequently recorded. Finally, emotion regulation was assessed via the Brunel mood scale questionnaire. RESULTS: The results revealed that attention was significantly lower in elderly females than in elderly males. Depression and vigor were significantly higher in elderly females than in elderly males. Brain activity of the slow (delta and theta) and fast (beta and high beta) waves was significantly higher in elderly females than in elderly males. Moreover, attention was negatively correlated with the theta wave, whereas delayed recall was positively correlated with the theta wave and salivary cortisol. Depression was positively correlated with the high beta wave and language skill, whereas the high beta wave was negatively correlated with visuoconstructional skill. CONCLUSION: The brain activity, emotion, and cortisol were influenced by cognitive impairments, although the relation of brain activity with glucocorticoid hormones remains inconclusive. This finding may be useful to the brain aging process, promote healthy brain aging, and prevent neurodegenerative conditions.


Assuntos
Encéfalo/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Emoções , Hidrocortisona/metabolismo , Idoso , Atenção , Depressão/fisiopatologia , Eletroencefalografia , Ensaio de Imunoadsorção Enzimática , Função Executiva , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Saliva/metabolismo , Autocontrole , Fatores Sexuais
19.
Br J Radiol ; 92(1102): 20190057, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31287719

RESUMO

Breast cancer is the most common cancer among females worldwide and large volumes of breast images are produced and interpreted annually. As long as radiologists interpret these images, the diagnostic accuracy will be limited by human factors and both false-positive and false-negative errors might occur. By understanding visual search in breast images, we may be able to identify causes of diagnostic errors, find ways to reduce them, and also provide a better education to radiology residents. Many visual search studies in breast radiology have been devoted to mammography. These studies showed that 70% of missed lesions on mammograms attract radiologists' visual attention and that a plethora of different reasons, such as satisfaction of search, incorrect background sampling, and incorrect first impression can cause diagnostic errors in the interpretation of mammograms. Recently, highly accurate tools, which rely on both eye-tracking data and the content of the mammogram, have been proposed to provide feedback to the radiologists. Improving these tools and determining the optimal pathway to integrate them in the radiology workflow could be a possible line of future research. Moreover, in the past few years deep learning has led to improving diagnostic accuracy of computerized diagnostic tools and visual search studies will be required to understand how radiologists interact with the prompts from these tools, and to identify the best way to utilize them. Visual search in other breast imaging modalities, such as breast ultrasound and digital breast tomosynthesis, have so far received less attention, probably due to associated complexities of eye-tracking monitoring and analysing the data. For example, in digital breast tomosynthesis, scrolling through the image results in longer trials, adds a new factor to the study's complexity and makes calculation of gaze parameters more difficult. However, considering the wide utilization of three-dimensional imaging modalities, more visual search studies involving reading stack-view examinations are required in the future. To conclude, in the past few decades visual search studies provided extensive understanding about underlying reasons for diagnostic errors in breast radiology and characterized differences between experts' and novices' visual search patterns. Further visual search studies are required to investigate radiologists' interaction with relatively newer imaging modalities and artificial intelligence tools.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mama/diagnóstico por imagem , Erros de Diagnóstico , Reconhecimento Visual de Modelos/fisiologia , Radiologistas , Atenção/fisiologia , Aprendizado Profundo , Diagnóstico por Computador/métodos , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Mamografia/métodos , Pesquisa , Ultrassonografia Mamária/métodos
20.
Psychol Aging ; 34(6): 836-847, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31259565

RESUMO

Judgments of learning (JOLs) can improve younger adults' associative learning of related information. One theoretical explanation for this finding is that JOLs strengthen the relationship between the cue and target words of a related word pair. This cue-strengthening hypothesis is particularly relevant for older adults because learning interventions that enhance associations between items typically benefit their learning. Thus, we investigated the degree to which JOLs have a direct influence on older adults' learning. To do so, older and younger adults studied a list of related word pairs (Experiments 1 and 2) or weakly related word pairs (Experiments 3, 4, and 5). Half of the participants made a JOL for each pair and half did not. After a filled 3-min retention interval, participants took a cued-recall test. In all experiments, older adults' memory performance was not impacted by making JOLs. By contrast, younger adults who made JOLs recalled significantly more than those who did not. JOLs may not have modified older adults' learning because of age-related deficits in processing that limited the degree to which JOLs strengthened cue-target relationships. It is also possible that JOLs encourage attentional reorienting, which older adults do not benefit from because they are already engaged with the materials. An important direction for future work will be to explore these possibilities, as well as others. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Idoso/psicologia , Envelhecimento/fisiologia , Aprendizagem por Associação/fisiologia , Julgamento/fisiologia , Rememoração Mental/fisiologia , Tempo de Reação/fisiologia , Adulto , Atenção , Sinais (Psicologia) , Feminino , Humanos , Aprendizagem , Masculino , Memória , Pessoa de Meia-Idade , Adulto Jovem
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