Made available in DSpace on 2015-04-14T13:22:08Z (GMT). No. of bitstreams: 1 444694.pdf: 1372805 bytes, checksum: d99054398e65ef064a183a062cb4e27d (MD5) Previous issue date: 2012-12-06 / The Bells Test (BT) is one of the most traditionally used neuropsychological instruments in the diagnosis of hemineglect and attention deficits. Based on a cancellation paradigm, the original Canadian version also known as Test des Cloches was adapted to Brazilian population, in a project that also involved the development of a second version of the task which added visually related distractors to the original stimuli. The aim of this thesis was to collect evidence toward the validity and reliability of both versions of the instrument, as well as to investigate whether age and education had an impact in individuals performance in these tasks. In the process, the performance in this test was normalized according to both age and education. Three empirical studies were conducted. The first study looked for evidence toward the construct/convergent validity and reliability of the instrument in a sample of 66 healthy adults, who completed both versions of the BT as well as other measures of sustained attention (AS, AC-15 and NEUPSILIN Line Cancelling Task). Reliability was analyzed by means of an analysis of test-retest. The second study investigated the influence of age and education in the attentional process, obtaining norms for specific groups divided by age and education. A total of 341 individuals aged between 19 and 75, with a minimum of 5 years of schooling, took part in this study. The third study collected evidence toward the criterion validity of the BT through the assessment of individuals with previously established clinical conditions which should interfere in their performance of the task. The sample was comprised of 30 patients with right brain damage (RBD) and 30 control individuals. Overall, the findings of all three studies suggest that the BT has adequate validity in respect to external variables, both related to performance in other assessment tools of attention and the presence of visual hemineglect. Age and education proved to influence performance in the BT, affecting both the number of omissions and the time taken to perform the test, all of which was reflected in normative data. Studies on different clinical samples with possible attention deficits and/or hemispatial neglect will be carried out so as to seek further evidence regarding the sensitivity and specificity of the BT in Brazilian population. / O Teste de Cancelamento dos Sinos (TS) ? uma das tarefas cl?ssicas na avalia??o neuropsicol?gica para o diagn?stico da s?ndrome de hemineglig?ncia visual e de d?ficits atencionais por meio de um paradigma de cancelamento. A vers?o original canadense Test des Cloches ou Bells Test foi adaptada para a popula??o brasileira, desenvolvendo-se, ainda, uma segunda vers?o alternativa do teste, com a inclus?o de distratores visualmente relacionados. Esta tese visou a investigar evid?ncias de validade e de fidedignidade das duas vers?es do instrumento, verificando-se o papel da idade e da escolaridade no desempenho por eles mensurados, obtendo-se, ainda, normas segundo estes fatores, por meio de tr?s estudos emp?ricos. O primeiro estudo avaliou evid?ncias de validade de construto/convergente e de fidedignidade do instrumento em uma amostra de 66 adultos saud?veis, avaliados com ambas as vers?es do TS e com outros testes que avaliam aten??o (AS, AC-15 e Cancelamento de linhas do NEUPSILIN). A fidedignidade do TS foi analisada mediante a t?cnica de teste-reteste. O segundo estudo investigou a influ?ncia da idade e da escolaridade no processamento atencional e obteve normas por grupos et?rios e educacionais. Participaram 341 adultos saud?veis com idades de 19 a 75 anos, com no m?nimo de 5 anos de escolaridade. O terceiro estudo averiguou evid?ncias de validade com rela??o a crit?rios externos cl?nicos. Participaram 30 pacientes com les?o de hemisf?rio direito (LHD) comparados a 30 adultos saud?veis quanto ao seu desempenho no TS. Os achados dos tr?s estudos sugeriram ?ndices de validade por rela??o com vari?veis externas, tanto de desempenho com outros testes que mensuram componentes cognitivos semelhantes como com o crit?rio de LHD e de s?ndrome de hemineglig?ncia. A escolaridade e a idade foram fatores que influenciaram nas vari?veis das omiss?es e do tempo, norteando dados normativos dos TS. Estudos com diferentes amostras cl?nicas com poss?veis d?ficits atencionais e/ou hemeglig?ncia ser?o conduzidos em busca de ?ndices de sensibilidade e especificidade do TS na popula??o brasileira.

Made available in DSpace on 2015-04-14T13:22:00Z (GMT). No. of bitstreams: 1 437216.pdf: 895942 bytes, checksum: f5b95d2182d468d69873678ea24b2f51 (MD5) Previous issue date: 2012-01-17 / Attention is a cognitive function that is very often impaires in neurological disorders, such as stroke or traumatic brain injury (TBI). Among the instruments that evaluate visual selective attention by means of a cancellation paradigm, The Bells Test (BT) is one of the most used and internationally known. The study of hemineglect syndrome in which patients neglect the contralateral or ipsilateral visual hemifield due to a neurological disorder- with tests of attention and visuoperception is still under development. This dissertation aimed to characterize the performance of patients with stroke or TBI in the BT. In the first study, we systematically reviewed articles with cancellation tasks in neuropsychological testing of these populations. Searching with the following keywords representing the constructs cancellation, stroke and TBI in the databases PubMed, PsycINFO and LILACS, we found 86 studies with 26 cancellation paradigms. In the second study we compared the performance between groups of 46 patients after unilateral stroke and 46 matched healthy controls, establishing as well the percentage frequency of deficits and analysed the dissociations between cases in TS. Patients with right brain damage (RBD) showed an inferior accuracy performance when compared to controls, also differing from left brain damaged adults (LBD), showing a slower speed processing. We identified 22% of RBD patients with HN, and a greater prevalence of disorganized strategies. In the third and last study, we compared the performance in TS between TBI patients and matched healthy controls. There was a poorer performance of patients with TBI with a greater number of omissions on the left side and lower speed processing. In addition, suggestive signs of HN were found in 38% of the sample of TBI patients. More research is needed to characterize clinical syndromes regarding the occurrence of HN after a TBI through the traditionally known cancellation paradigm. / A aten??o ? uma das fun??es cognitivas que se encontra muito frequentemente deficit?ria em popula??es cl?nicas neurol?gicas, tais como Acidente Vascular Cerebral e Traumatismo Cranioencef?lico (TCE). O Teste de Cancelamento dos Sinos (TS), dentre os instrumentos que operacionalizam o paradigma de cancelamento destinados ? avalia??o neuropsicol?gica da aten??o concentrada seletiva visual, ? um dos mais utilizados e valorizados internacionalmente. O estudo da hemineglig?ncia s?ndrome em que pacientes negligenciam o hemicampo visual contra ou ipsilateral ? les?o neurol?gica a partir da avalia??o por testes de aten??o e visuopercep??o ainda est? em desenvolvimento. Esta pesquisa buscou caracterizar a avalia??o da aten??o de pacientes com AVC ou TCE por tarefas de cancelamento visual, verificando-se como tais pacientes desempenham no TS. No primeiro estudo, revisaram-se sistematicamente pesquisas com tarefas de cancelamento no exame neuropsicol?gico destas popula??es. Com palavras-chave dos construtos cancelamento, AVC e TCE nas bases de dados PubMed, PsycINFO e LILACS, encontraram-se 86 estudos, com 26 paradigmas de cancelamento. No segundo estudo, foi comparado o desempenho entre grupos de 46 pacientes p?s-AVC unilateral e 46 controles, o percentual da frequ?ncia de d?ficits, e de dissocia??es entre casos no TS. Os pacientes com les?o de hemisf?rio direito (LHD) apresentaram desempenho inferior aos controles em acur?cia, diferenciando-se tamb?m dos com les?o de hemisf?rio esquerdo (LHE) pelo tempo maior de execu??o. Identificaram-se 22% dos pacientes com LHD com HN, al?m de um maior predom?nio de estrat?gias desorganizadas. No terceiro e ?ltimo estudo foi comparado o desempenho de pacientes com TCE e controles pelo TS. Os pacientes com TCE apresentaram pior escore de omiss?es ? esquerda menos direita e maior tempo de execu??o. Foram observados dados sugestivos de HN em 38% da amostra. Mais pesquisas s?o necess?rias para caracterizar as s?ndromes cl?nicas relacionadas ? ocorr?ncia de HN p?s TCE atrav?s do tradicionalmente conhecimedo paradigma de cancelamento.