Dentate gyrus-selective colchicine lesion and performance in temporal and spatial tasks

Autor(es)

Costa, Valéria Catelli Infantozzi da ^[1] ; Bueno, José Lino Oliveira ; Xavier, Gilberto Fernando

Afiliação do(s) autor(es)

^[1] Universidade de São Paulo (USP). Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto. Departamento de Psicologia e Educação - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Behavioural Brain Research; v. 160, n. 2, p. 286-303, May 2005.
• Área do conhecimento: Ciências Humanas - Psicologia
• Assunto(s): Memória (psicologia) Hipocampo Cognição

Resumo

The effects of multiple-site, intradentate, colchicine injections on the performance of a temporal. 'differential reinforcement of low rates of responding' (DRL-20 s) task and a spatial, 'delayed non-matching-to-place' (DNMTP) task in a plus-maze were investigated in rats trained in both tasks prior to the lesion. Quantitative analysis revealed a greater than 86% reduction in the dentate gyrus (DG) of the colchicine-injected rats compared to the sham-operated controls. Dentate gyrus damage rendered rats less efficient than sham-operated controls in the performance of the DRL-20 s task. The DRL inter-response time (IRT) distribution for the DG-lesioned rats and the sham-operated controls was similar; however, while the distribution peak for the control rats was 20 s, it was 16 s for the DG-lesioned rats, indicating that the latter rats underestimated time. Performance of the DG-lesioned rats was also disrupted in the DNMTP task. However, DG-lesioned rats recovered control levels of performance during repeated training with an intertrial interval equal to 3 s. An increase in intertrial interval in lesioned and sham-operated controls disrupted performance in both groups; however, while DG-lesioned rats performed at chance levels when the intertrial interval was increased to 4 min or longer, the sham-operated controls performed at chance levels only when the intertrial interval was increased to 16 min. These results seem most parsimoniously interpreted following the cognitive map theory of hippocampal function. (AU)

• Processo FAPESP: 94/05717-8 - A lesão seletiva das células piramidais do campo CA3 como modelo para testar a hipótese de continuidade funcional na formação hipocampal
• Beneficiário: Alexandre de Campos
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 00/10665-0 - Avaliação funcional do subcampo CA3 do hipocampo quanto ao processamento de informações mnêmicas de natureza não espacial
• Beneficiário: Alexandre de Campos
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 93/01714-1 - Efeitos de lesoes do ca1 e giro denteado do hipocampo, no desempenho de ratos em tarefas visuais, espaciais e temporais.
• Beneficiário: Valéria Catelli Infantozzi da Costa
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 99/10323-2 - Formação hipocampal e memória: contribuição diferencial dos sub-campos e seus componentes septais e temporais
• Beneficiário: Gilberto Fernando Xavier
• Modalidade de apoio: Auxílio à Pesquisa - Regular