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1.
Contemp Clin Dent ; 11(2): 162-164, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33110330

RESUMO

Myiasis is an invasion of tissues and organs of humans or animals by fly larvae. Oral myiasis is a rare pathology associated with a medical condition, poor oral hygiene, mouth breathing, and incompetent lip. We present a case of oral myiasis of the maxillary anterior region of the palate, in a 12-year-old male with cerebral palsy and poor oral hygiene. The diagnosis was made on the presence of larvae. The mechanical removal of larvae with hemostat was carried out with ivermectin oral therapy.

2.
Transplant Proc ; 45(9): 3262-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24182797

RESUMO

BACKGROUND: "Acute tubular necrosis (ATN)-like" changes in type I acute antibody- mediated rejection (AAMR) have been proposed since 2005, but the presence of "ATN-like" injury in AAMR has not well been established. The aim of this study was to confirm the presence of acute tubular injury in type I AAMR, using the specific proximal tubular injury marker, kidney injury molecule-1 (KIM-1). DESIGN: The study included 3 groups of cases, namely, a negative control group (normal nontransplantation renal parenchyma as group 1, n = 11), a positive control group (transplant ATN with negative C4d staining as group 2, n = 12), and study cases (type 1 AAMR as group 3, n = 19). Biopsy specimens from all groups were stained immunohistochemically for KIM-1 (monoclonal antibody) and KIM-1 staining intensity in proximal tubules was graded from 0.5 to 3+. Clinical indices were also correlated and analyzed. RESULTS: Group 1 demonstrated significantly lower serum creatinine levels (1.02 ± 0.10 mg/dL) when compared with both group 2 and group 3. Both groups 2 and 3 showed similar serum creatinine levels (4.02 ± 0.59 mg/dL in group 2 and 3.24 ± 0.34 mg/dL in group 3). The negative control group demonstrated negative proximal tubule staining for KIM-1, whereas both groups 2 and 3 showed positive KIM-1 staining in proximal tubules (intensity ranging from 1+ to 3+ in group 2 and from 0.5 to 3+ in group 3). CONCLUSION: Our results, using KIM-1 immunohistochemistry, demonstrated that acute tubular injury is an important component of type I AAMR.


Assuntos
Anticorpos/imunologia , Rejeição de Enxerto/imunologia , Túbulos Renais/patologia , Biópsia , Estudos de Casos e Controles , Humanos
3.
Transplant Proc ; 45(9): 3269-72, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24182798

RESUMO

BACKGROUND: Successful kidney transplantation despite positive crossmatch (+CXM) before transplantation is well recognized in combined liver-kidney transplant (CLKT) recipients. This is probably due to immunologic protection of the renal allograft (RA) conferred by the liver allograft. However, occurrences of antibody-mediated rejection and poor long-term RA outcome is also documented with +CXM CLKT recipients, suggesting that such immunologic protection may not be universal. METHODS: A total of 1,401 CLKT recipients with known status of pre-transplantation CXM were identified from the United Network for Organ Sharing registry from January 1, 1986, to December 31, 2006. Univariate analysis for significant differences in clinical variables and Kaplan-Meier estimate for patient and graft survivals were performed. The results were compared between positive and negative CXM groups. RESULTS: Pre-transplantation +CXM was seen in 17.3% (242/1401) of CLKT recipients studied. The demographic and clinical characteristics were similar between the groups, except for higher panel reactive antibody level and CXM positivity in female recipients. Outcome analysis showed higher RA rejection (19.3% vs 10.8%; P = .026) and increased hospital length of stay (37.3 ± 46.0 vs 28.8 ± 33.2 days; P = .028) in the +CXM group. RA survivals at 1, 3, and 5 years were 8%, 7%, and 6% lower in the +CXM group. The patient and liver allograft survivals were not different between the groups. CONCLUSIONS: In CLKT recipients with pre-transplantation +CXM, the immunologic protection of RA conferred by the liver allograft is less robust than previously perceived and may lead to higher rejection rate and poor RA outcome. This can be mitigated with routine pre-transplantation CXM.


Assuntos
Teste de Histocompatibilidade , Transplante de Rim , Transplante de Fígado , Resultado do Tratamento , Feminino , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Masculino , Sistema de Registros , Transplante Homólogo
4.
J Endod ; 39(6): 806-12, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23683283

RESUMO

INTRODUCTION: The aim of this study was to investigate the combined effect of statin and α-tricalcium phosphate (α-TCP) on odontoblastic differentiation of human dental pulp cells and to compare them with mineral trioxide aggregate (MTA). METHODS: Experimental cements were prepared with TCP containing simvastatin and atorvastatin. Cell proliferation, cell adherence on a dentin disc, alkaline phosphatase (ALP) activity, expression of osteogenic/odontoblastic markers, and mineralization of the human dental pulp cells on experimental cement and MTA were assessed. RESULTS: The cell growth and ALP activity of TCP containing simvastatin-treated cells was greater than MTA-treated cells. The mineralization and messenger RNA expression of markers (ie, dentin sialophosphoprotein, dentin matrix protein 1, bone morphogenetic protein 2, ALP, and osteonectin) of TCP containing simvastatin- and TCP containing atorvastatin-treated cells were comparable with MTA-treated cells. The enhanced cell proliferation and similar level of ALP of TCP-treated cells compared with the control indicate that α-TCP is an effective osteoconductive material. The differentiation effect observed in TCP containing simvastatin- and TCP containing atorvastatin-treated cells is attributed to the effect of statin. CONCLUSIONS: The results suggest that α-TCP can be used for local delivery of statin as a pulp capping material to accelerate reparative dentin formation.


Assuntos
Materiais Biocompatíveis/farmacologia , Fosfatos de Cálcio/farmacologia , Polpa Dentária/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Adolescente , Adulto , Fosfatase Alcalina/efeitos dos fármacos , Compostos de Alumínio/farmacologia , Atorvastatina , Biomarcadores/análise , Proteína Morfogenética Óssea 2/efeitos dos fármacos , Calcificação Fisiológica/efeitos dos fármacos , Compostos de Cálcio/farmacologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Polpa Dentária/citologia , Dentina/ultraestrutura , Combinação de Medicamentos , Proteínas da Matriz Extracelular/efeitos dos fármacos , Ácidos Heptanoicos/farmacologia , Humanos , Odontoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteonectina/efeitos dos fármacos , Óxidos/farmacologia , Fosfoproteínas/efeitos dos fármacos , Pirróis/farmacologia , Sialoglicoproteínas/efeitos dos fármacos , Silicatos/farmacologia , Sinvastatina/farmacologia , Adulto Jovem
6.
Transplant Proc ; 43(5): 1629-33, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21693247

RESUMO

BACKGROUND: The Banff criteria (from 2005 to 2009) use "T cell-mediated rejection" to indicate acute cellular rejection. Vasculitis in smaller arteries is an important diagnostic criterion for moderate and severe T cell-mediated rejection. The renal allograft endothelium is a significant target of inflammatory response-mediated tissue damage. Medium-size arteries (arcuate arteries) are mostly absent in routine allograft biopsies, so identification of vasculitis relies on its identification in small arteries (arterioles to interlobar arteries). Although inflammation in terminal vessels such as the glomerular capillaries has been previously recognized, their role in grading the rejection process is not well characterized. We therefore evaluated the expression of CD3-positive T lymphocytes and CD68-positive macrophages in glomeruli, small arteries, and arcuate arteries of nephrectomy specimens obtained from transplant and renal tumor patients. METHODS: The study group included 21 renal explant subjects with nonreversible moderate to severe T cell-mediated rejection (IIa to III) and/or severe chronic changes. The control group comprised 17 individuals with nephrectomy for renal tumors. In each case, a large renal section from cortex to medulla was stained for CD3 and CD68 by immunohistochemical method. CD3-positive T lymphocytes and CD68-positive macrophages per balanced high-power field were counted in glomeruli, interlobar arteries, and arcuate arteries. RESULTS: In control kidney sections, neither CD3-positive T lymphocytes nor CD68-positive macrophages were noted in glomeruli, interlobar arteries, or arcuate arteries. In the study group, 15/21 showed diffuse C4d positivity. Also in the study group, positive CD3 and CD68 counts in glomeruli were significantly correlated to both interlobar and arcuate artery counts by linear regression analysis. CONCLUSION: We conclude that in renal allograft biopsies, T lymphocytes and macrophages in the glomeruli not only represent a separate entity, "transplant glomerulitis," but also may be a surrogate marker of vasculitis present in larger vascular beds. Comparable amounts of T cells and macrophages imply that "acute cellular rejection" may be a better terminology to reflect the true inflammatory status.


Assuntos
Biomarcadores/análise , Glomerulonefrite/etiologia , Vasculite/diagnóstico , Humanos , Vasculite/complicações
8.
Ergonomics ; 53(8): 951-61, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20658389

RESUMO

The present study assessed the impact of task load and level of automation (LOA) on task switching in participants supervising a team of four or eight semi-autonomous robots in a simulated 'capture the flag' game. Participants were faster to perform the same task than when they chose to switch between different task actions. They also took longer to switch between different tasks when supervising the robots at a high compared to a low LOA. Task load, as manipulated by the number of robots to be supervised, did not influence switch costs. The results suggest that the design of future unmanned vehicle (UV) systems should take into account not simply how many UVs an operator can supervise, but also the impact of LOA and task operations on task switching during supervision of multiple UVs. The findings of this study are relevant for the ergonomics practice of UV systems. This research extends the cognitive theory of task switching to inform the design of UV systems and results show that switching between UVs is an important factor to consider.


Assuntos
Automação , Robótica/instrumentação , Análise e Desempenho de Tarefas , Adolescente , Adulto , Simulação por Computador , Ergonomia , Feminino , Humanos , Masculino , Adulto Jovem
9.
Transplant Proc ; 42(5): 1641-2, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20620491

RESUMO

Urologic malignancy is a relatively uncommon but serious complication following kidney transplantation. The reported prevalence of renal cell carcinoma (RCC) of the native kidneys is 4.4% and of bladder malignancy is 2.6%. However, presently there are no universal guidelines for prospective screening of urologic malignancies after kidney transplantation. We routinely monitored all renal transplant recipients for microscopic hematuria and persistent hematuria (>3 separate occasions) results in imaging studies (ultrasound or computed tomography scan) of both native kidneys and the allograft. Cystoscopy is performed if imaging studies are negative. This retrospective study identified a total of 18 urologic malignancies among the study cohort, which consisted of 539 patients with an incidence of 3.3% (12 cases of RCC of native kidneys [10/12 had hematuria], and six cases of bladder and ureteral malignancies [6/6 had hematuria]). There were no significant differences between cyclosporine- and tacrolimus-based immunosuppression (IS). Among RCC recipients, two lost the allograft from chronic allograft nephropathy and one patient died unrelated to malignancy. Among patients with bladder and ureteral malignancies, two lost the graft possibly from IS reduction and one had BK virus nephropathy prior to diagnosis of bladder carcinoma. In conclusion, screening transplant recipients routinely for persistent microscopic hematuria may identify urologic malignancies in renal transplant recipients.


Assuntos
Carcinoma de Células Renais/diagnóstico , Hematúria/etiologia , Neoplasias Renais/diagnóstico , Transplante de Rim/efeitos adversos , Neoplasias Urológicas/diagnóstico , Carcinoma de Células Renais/epidemiologia , Carcinoma de Células Renais/cirurgia , Hematúria/epidemiologia , Humanos , Neoplasias Renais/epidemiologia , Neoplasias Renais/cirurgia , Transplante de Rim/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/epidemiologia
11.
Transpl Infect Dis ; 11(4): 349-52, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19422668

RESUMO

Disseminated cryptococcal infection occurs mainly in the immunocompromised host, particularly in those with impaired cellular immunity. The treatment outcome depends not only on the duration and choice of antifungal therapy, but also on the activity of the organism to persist in different parts of the body despite therapy. We present a case of persistence of cryptococcal infection in the parathyroid gland in a kidney transplant recipient. A 38-year-old male renal transplant recipient diagnosed to have disseminated cryptococcosis was treated with discontinuation of immunosuppression, amphotericin B, and flucytosine for 2 weeks, and fluconazole subsequently. Dialysis was initiated when graft function deteriorated after discontinuation of immunosuppression. The patient showed no clinical signs of active cryptococcal infection on fluconazole therapy. One year after the diagnosis of cryptococcosis, and still on fluconazole, he underwent parathyroidectomy, for severe secondary hyperparathyroidism. Surprisingly, active cryptococcal infection with necrotizing granulomatous inflammation was demonstrated in the parathyroid, despite being on therapy. This patient illustrates that persistence of fungal infection despite prolonged therapy can occur in unusual sites such as the parathyroid and may be a source for future recurrence and dissemination.


Assuntos
Criptococose/microbiologia , Cryptococcus neoformans/isolamento & purificação , Transplante de Rim/efeitos adversos , Glândulas Paratireoides/microbiologia , Adulto , Antifúngicos/administração & dosagem , Antifúngicos/uso terapêutico , Criptococose/tratamento farmacológico , Esquema de Medicação , Fluconazol/administração & dosagem , Fluconazol/uso terapêutico , Humanos , Masculino , Glândulas Paratireoides/patologia , Glândulas Paratireoides/cirurgia , Paratireoidectomia
12.
Proc Natl Acad Sci U S A ; 106(9): 3633-8, 2009 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-19211801

RESUMO

It is widely appreciated that neurotransmission systems interact in their effects on human cognition, but those interactions have been little studied. We used genetics to investigate pharmacological evidence of synergisms in nicotinic/muscarinic interactions on cognition. We hypothesized that joint influences of nicotinic and muscarinic systems would be reflected in cognitive effects of normal variation in known SNPs in nicotinic (CHRNA4 rs1044396) and muscarinic (CHRM2 rs8191992) receptor genes. Exp. 1 used a task of cued visual search. The slope of the cue size/reaction time function showed a trend level effect of the muscarinic CHRM2 SNP, no effect of the nicotinic CHRNA4 SNP, but a significant interaction between the 2 SNPs. Slopes were steepest in individuals who were both CHRNA4 C/C and CHRM2 T/T homozygotes. To determine the specificity of this synergism, Exp. 2 assessed working memory for 1-3 locations over 3 s and found no significant effects on either SNP. Interpreting these results in light of Sarter's [Briand LA, et al. (2007) Modulators in concert for cognition: Modulator interactions in the prefrontal cortex. Prog Neurobiol 83:69-91] claims of tonic and phasic modes of cholinergic activity, we argue that reorienting attention to the target after invalid cues requires a phasic response, dependent on the nicotinic system, whereas orienting attention to valid cues requires a tonic response, dependent on the muscarinic system. Consistent with that, shifting and scaling after valid cues (tonic) were strongest in CHRNA4 C/C homozygotes who were also CHRM2 T/T homozygotes. This shows synergistic effects within the human cholinergic system.


Assuntos
Atenção/fisiologia , Polimorfismo de Nucleotídeo Único/genética , Receptores Muscarínicos/metabolismo , Receptores Nicotínicos/metabolismo , Percepção Visual/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Genótipo , Humanos , Memória , Pessoa de Meia-Idade , Receptores Muscarínicos/genética , Receptores Nicotínicos/genética
15.
Transplant Proc ; 38(10): 3663-5, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17175361

RESUMO

UNLABELLED: Significant chronic kidney disease (CKD) occurs following orthotopic liver transplant (OLT). Since CKD is associated with increased cardiovascular events, mortality, and hepatic allograft dysfunction, early recognition of CKD and implementation of changes may improve the long-term outcome. The purpose of this study was to determine the burden of renal disease following OLT. PATIENTS AND METHODS: We retrospectively reviewed our OLT recipients from 1997 until 2004. We calculated glomerular filtration rates (GFR) using the Modification of Diet in Renal Disease study (MDRD) method. The GFRs were further subdivided into pre-MELD and post-MELD eras. RESULTS: During the study period, we performed 407 OLTs. We censored data from living donor liver transplants (n = 14), combined liver-kidney transplants (n = 12), and from patients whom we did not have complete data for 6 months after transplant (n = 40). Mean MELD score at the time of transplant was 18 +/- 7 (mean +/- standard deviation). The mean GFR at 6 months following OLT was 63.7 +/- 30.2 mL/min per 1.73 m(2). Only 14% (n = 47) of our patients had normal renal function at 6 months, while 78% (n = 266) of our patients had mild to moderate risk for renal failure. Eight percent (n = 28) had stage 4 or 5 CKD. There were no differences between the pre-MELD and post-MELD GFRs. CONCLUSIONS: The burden of renal disease is significant in our patient population at 6 months posttransplantation. It may be important to introduce CKD management as early as 6 months after transplant to impact the outcomes of OLT recipients.


Assuntos
Nefropatias/economia , Nefropatias/epidemiologia , Transplante de Fígado/efeitos adversos , Adulto , Doença Crônica , Efeitos Psicossociais da Doença , Taxa de Filtração Glomerular , Humanos , Michigan , Estudos Retrospectivos , Índice de Gravidade de Doença
17.
Transplant Proc ; 38(5): 1283-5, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16797282

RESUMO

An ideal method for quality of life (QOL) assessment in renal transplant recipients (RTR) has not yet been determined. Present assessments of QOL in RTR are lengthy, cumbersome to administer, and difficult to interpret. We used a previously validated single question QOL scale score (QLS) that directly asks about the patients' overall assessment of their QOL; "Considering all parts of my life-physical, emotional, social, spiritual, and financial--over the past 2 days the quality of my life has been ... ". The QLS ranges from 0 ("very bad") to 10 ("excellent"). Patients were contacted prior to their routine office visit when they were free of acute medical problems. Fifty RTR participated. Psychosocial and medical variables included the Beck Depression Inventory, Illness Effects Questionnaire, Multidimensional Scale of Perceived Social Support, time since transplant, age, creatinine, hemoglobin, and albumin levels. Of the patients, 64% were African-American and 48% were women; 94% of patients had a score>5. Mean QLS was 7.5+/-2.3. Perception of a better QOL correlated with less perception of depression and illness effects and with perception of greater social support and satisfaction with life (all P<.05). Perception of QOL did not correlate with age, time since transplantation, creatinine, hemoglobin or albumin levels. We concluded that QLS is a quick tool to measure subjective QOL in RTR for correlation with psychosocial factors of interest in this group. These studies should be replicated in larger multiethnic populations.


Assuntos
Atitude Frente a Saúde , Transplante de Rim/psicologia , Qualidade de Vida , Adulto , Idoso , Depressão , Feminino , Humanos , Falência Renal Crônica/psicologia , Masculino , Pessoa de Meia-Idade , Testes Psicológicos , Psicologia , Apoio Social
18.
Transplant Proc ; 37(5): 2060-2, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15964338

RESUMO

INTRODUCTION: The use of mycophenolate mofetil (MMF) in renal transplantation results in a 50% lower incidence of acute rejection compared to azathioprine (AZA). However, the graft survival reports are conflicting: the European trial and US database analysis suggest better survival with MMF, an observation that was not seen in the US and tricontinental studies. METHODS: We retrospectively reviewed our single-center experience (60% African-Americans) comparing the serum creatinine (SCr) values and 3-year actual graft survival with MMF versus AZA-based immunosuppression. Group I included patients transplanted between January 1990 and December 1992 on cyclosporine (CSA), AZA, and steroids; group II subjects, from January 1996 to December 1998 on CSA, MMF, and steroids. We analyzed SCr and all causes of graft losses at 3, 6, 12, 18, 24, and 36 months posttransplantation. RESULTS: The patient demographics were similar in both groups as was the mean SCr values at different times. The time-group interaction for SCr, the Kruskal-Wallis test for SCr for different categories (<1.5, 1.5 to 2.0, 2.0 to 2.5, and >2.5 mg/dL) and the all-cause graft loss between the two groups were not significantly different. CONCLUSION: Our results failed to show better long-term actual graft survival despite the 6-year interval between the two groups. These findings agree with the results of the United States and the tricontinental studies. A lower incidence of acute rejection early after transplantation observed with MMF may not always translate into a long-term benefit, possibly due to the influence of nonimmunological factors, such as hypertension, calcineurin inhibitor toxicity, more frequent cytomegalovirus infections, and increased attempts to withdraw steroids using MMF-based protocols.


Assuntos
Azatioprina/uso terapêutico , Sobrevivência de Enxerto/efeitos dos fármacos , Imunossupressores/uso terapêutico , Transplante de Rim/fisiologia , Ácido Micofenólico/análogos & derivados , Corticosteroides/uso terapêutico , Creatinina/sangue , Ciclosporina/uso terapêutico , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Transplante de Rim/imunologia , Transplante de Rim/mortalidade , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/uso terapêutico , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo
19.
Transpl Infect Dis ; 4(2): 102-7, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12220248

RESUMO

Disseminated microsporidiosis is diagnosed uncommonly in patients not infected with human immunodeficiency virus (HIV). We present a case of disseminated microsporidiosis in a renal transplant recipient who was seronegative for HIV. Chromotrope-based stains were positive for microsporidia in urine, stools, sputum, and conjunctival scrapings. Electron microscopy, immunofluorescence, polymerase chain reaction, and cultures of renal tissue identified the organism as Encephalitozoon cuniculi. The patient was treated with oral albendazole and topical fumagillin with clinical improvement. In addition, she underwent a transplant nephrectomy and immunosuppressive therapy was withdrawn. Follow-up samples were negative for microsporidia. However, the patient developed central nervous system manifestations and died. An autopsy brain tissue specimen demonstrated E. cuniculi by immunofluorescent staining. Disseminated microsporidiosis must be considered in the differential diagnosis of multiorgan involvement in renal allograft recipients.


Assuntos
Transplante de Rim/imunologia , Microsporidiose/diagnóstico , Animais , Antiprotozoários/uso terapêutico , Linhagem Celular , Encephalitozoon cuniculi/isolamento & purificação , Encephalitozoon cuniculi/ultraestrutura , Feminino , Humanos , Microsporidiose/tratamento farmacológico , Microsporidiose/parasitologia , Pessoa de Meia-Idade
20.
Brain Res Cogn Brain Res ; 12(3): 371-81, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11689297

RESUMO

The temporal dynamics of the spatial scaling of attention during visual search were examined by recording event-related potentials (ERPs). A total of 16 young participants performed a search task in which the search array was preceded by valid cues that varied in size and hence in precision of target localization. The effects of cue size on short-latency (P1 and N1) ERP components, and the time course of these effects with variation in cue-target stimulus onset asynchrony (SOA), were examined. Reaction time (RT) to discriminate a target was prolonged as cue size increased. The amplitudes of the posterior P1 and N1 components of the ERP evoked by the search array were affected in opposite ways by the size of the precue: P1 amplitude increased whereas N1 amplitude decreased as cue size increased, particularly following the shortest SOA. The results show that when top-down information about the region to be searched is less precise (larger cues), RT is slowed and the neural generators of P1 become more active, reflecting the additional computations required in changing the spatial scale of attention to the appropriate element size to facilitate target discrimination. In contrast, the decrease in N1 amplitude with cue size may reflect a broadening of the spatial gradient of attention. The results provide electrophysiological evidence that changes in the spatial scale of attention modulate neural activity in early visual cortical areas and activate at least two temporally overlapping component processes during visual search.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Potenciais Evocados/fisiologia , Percepção Espacial/fisiologia , Adulto , Sinais (Psicologia) , Eletroencefalografia , Feminino , Humanos , Masculino , Desempenho Psicomotor/fisiologia
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