Anorexia nervosa e retardo mental

OBJETIVO: Revisar a literatura pertinente, observando a prevalência, etiopatogenia, aspectos nutricionais, diagnóstico e tratamento da anorexia nervosa (AN) em pacientes com retardo mental (RM). MÉTODO: Revisão bibliográfica realizada nos sistemas Medline, SciELO e PubMed usando os descritores "transtornos alimentares", "anorexia nervosa" e "retardo mental". RESULTADOS: A AN pode se manifestar de formas atípicas em indivíduos com RM, exigindo critérios diagnósticos específicos. O mais utilizado atualmente é o Diagnostic Criteria for Psychiatric Disorders for Use with Adults with Learning Disabilities/Mental Retardation, conhecido por DC-LC. A prevalência é incerta e o tratamento ainda não está estabelecido, apesar de exigir treinamento específico da equipe. A alimentação costuma ser "pobre" e alimentos que engordam normalmente são evitados. Na maioria das vezes, é difícil acessar a complexa psicopatologia da AN nesses pacientes, em virtude das dificuldades de obter o relato de insatisfação e/ou distorção da imagem corporal, baixa autoestima e crenças alimentares. CONCLUSÃO: Muitos fatores indicam a necessidade de maiores estudos de AN no RM, entre eles a falta de critérios diagnósticos próprios validados e diretrizes para tratamento. Paralelamente, o debate da forma de acesso à conceitualização e ao tratamento dos distúrbios da imagem corporal nessa população deve ser intensificado.

Effects of caffeine on learning and memory in rats tested in the Morris water maze

We studied some of the characteristics of the improving effect of the non-specific adenosine receptor antagonist, caffeine, using an animal model of learning and memory. Groups of 12 adult male Wistar rats receiving caffeine (0.3-30 mg/kg, ip, in 0.1 ml/100 g body weight) administered 30 min before training, immediately after training, or 30 min before the test session were tested in the spatial version of the Morris water maze task. Post-training administration of caffeine improved memory retention at the doses of 0.3-10 mg/kg (the rats swam up to 600 cm less to find the platform in the test session, P<=0.05) but not at the dose of 30 mg/kg. Pre-test caffeine administration also caused a small increase in memory retrieval (the escape path of the rats was up to 500 cm shorter, P<=0.05). In contrast, pre-training caffeine administration did not alter the performance of the animals either in the training or in the test session. These data provide evidence that caffeine improves memory retention but not memory acquisition, explaining some discrepancies among reports in the literature.

Generalization of temporal order detection skill learning: two experimental studies of children with dyslexia

The objective of this study was to investigate the phenomenon of learning generalization of a specific skill of auditory temporal processing (temporal order detection) in children with dyslexia. The frequency order discrimination task was applied to children with dyslexia and its effect after training was analyzed in the same trained task and in a different task (duration order discrimination) involving the temporal order discrimination too. During study 1, one group of subjects with dyslexia (N = 12; mean age = 10.9 ± 1.4 years) was trained and compared to a group of untrained dyslexic children (N = 28; mean age = 10.4 ± 2.1 years). In study 2, the performance of a trained dyslexic group (N = 18; mean age = 10.1 ± 2.1 years) was compared at three different times: 2 months before training, at the beginning of training, and at the end of training. Training was carried out for 2 months using a computer program responsible for training frequency ordering skill. In study 1, the trained group showed significant improvement after training only for frequency ordering task compared to the untrained group (P < 0.001). In study 2, the children showed improvement in the last interval in both frequency ordering (P < 0.001) and duration ordering (P = 0.01) tasks. These results showed differences regarding the presence of learning generalization of temporal order detection, since there was generalization of learning in only one of the studies. The presence of methodological differences between the studies, as well as the relationship between trained task and evaluated tasks, are discussed.