Lesion of areas 17/18/19: effects on the cat's performance in a binary detection task

The ability of two cats to discriminate between two geometrical outline patterns in the presence of superimposed Gaussian visual noise-i.e. in a binary detection task--was tested before and after bilateral removal of cortical areas 17, 18 and 19. The detection probability PD was measured as a function of the signal-to-noise ratio. After a lesion of areas 17, 18 and 19 both cats were unable to carry out the discrimination tasks. Their detection performance dropped to chance level, but after an extensive phase of retraining (3 months) they regained the ability to discriminate visual patterns. It was thus possible to obtain detection curves and to determine a measure of a performance which is predominantly bound to be mediated by extra-geniculo-cortical systems. The detection capacity was abnormally low with both large and small patterns. However, the detection of stationary small patterns was similar to the performance of cats with 17/18 lesions; the detection of stationary large patterns was only slightly better than the detection of small patterns and much worse than the comparable performance of cats with 17/18 lesions. Furthermore the cats with lesions of areas 17/18/19 were unable to discriminate moving patterns, their performances being at chance level, whereas for the cats with 17/18 lesions the detection of moving and stationary patterns was equal

A influência das habilidades em consciência fonológica na terapia para os desvios fonológicos The influence of phonological awareness abilities in therapy for phonological disorder

Este trabalho teve como objetivo analisar as habilidades em consciência fonológica e o progresso (inventário fonético e fonológico e as generalizações) na terapia fonológica. O grupo pesquisado foi constituído por cinco crianças com desvio fonológico, com idades entre 5:0 e 6:11, submetidas à terapia fonológica. Foram analisados os resultados obtidos na avaliação da consciência fonológica pré-tratamento, a fim de verificar o desempenho das crianças quanto ao seu conhecimento fonológico. Realizou-se a avaliação fonológica pré e pós-tratamento, em que foi possível obter os inventários fonéticos e fonológicos dos sujeitos. Após, foram analisadas as generalizações obtidas com a terapia fonológica (itens lexicais não utilizados no tratamento, outras posições na palavra, dentro de uma classe de sons, outra classe de sons). Os resultados evidenciaram que não existe relação entre o desempenho em tarefas de consciência fonológica e os progressos na terapia. Tais resultados corroboram os achados da literatura, confirmando que crianças com desvio fonológico podem ser capazes de responder adequadamente a tarefas metalinguísticas como a consciência fonológica, sem que essa condição as auxilie a corrigir os desvios de sua fala. Sugere-se que este assunto seja mais bem investigado com um número maior de sujeitos, bem como com a avaliação da consciência fonológica pré e pós-terapia, no intuito de se obter dados generalizáveis os quais serão importantes para o entendimento dos casos de desvio fonológico.<br>This study aimed to analyze the phonological awareness skills and progress (phonetic and phonological inventory and generalizations) in phonological therapy. The research group consisted of five children presenting speech disorders, aged 5:0 and 6:11, subjected to phonological therapy. The results of the phonological awareness assessment were analyzed before the treatment in order to verify the performance of children and their phonological knowledge. The evaluation was performed before and after the treatment. It was possible to obtain the phonetic and phonological inventories of the subjects and, after that, the generalizations obtained with phonological therapy were analyzed (considering lexical items that were not used during treatment, other positions in word, within one sound class or another class of sounds). The results showed that there is no relation between the performance in phonological awareness tasks and the evolution of the phonological therapy. On the other hand, the results agree with the research findings from the literature, reinforcing the idea that, children with phonological disorder can be able to react properly to metalinguistic tasks such as phonological awareness without being able to correct their speech problems. Finally, it can be conclude that this research subject should be investigated deeper and another analysis should be carried out involving a higher number of subjects, including the phonological awareness evaluation before and after therapy. By doing this, it will be possible to obtain other important data to improve the treatment of phonological disorder