Behavioral assessment of auditory processing in adulthood: population of interest and tests - a systematic review

PURPOSE

To identify the behavioral tests used to assess auditory processing throughout adulthood, focusing on the characteristics of the target population as an interest group.

RESEARCH STRATEGIES

PubMed, CINAHL, Web of Science, and Scielo, databases were searched with descriptors: "auditory perception" or "auditory perception disorders" or "auditory processing" or "central auditory processing" or "auditory processing disorders" or "central auditory processing disorders" with adults OR aging.

SELECTION CRITERIA

Studies with humans included, the adult population from 18 to 64 years old, who performed at least one behavioral test to assess auditory processing in the absence of hearing loss.

DATA ANALYSIS

Data extraction was performed independently, using a protocol developed by the authors that included different topics, mainly the behavioral auditory tests performed and the results found.

RESULTS

Of the 867 records identified, 24 contained the information needed to answer the survey questions.

CONCLUSION

Almost all studies were conducted verify performance in one or two auditory processing tests. The target target population was heterogeneous, with the most frequent persons with diabetes, stuttering, auditory processing disorder, and noise exposure. There is little information regarding benchmarks for testing in the respective age groups.

Cortical auditory evoked potentials with different acoustic stimuli: Evidence of differences and similarities in coding in auditory processing disorders

OBJECTIVES

The use of cortical auditory evoked potentials allows for the study of the processing of acoustic signals at the cortical level, an important step in the diagnostic evaluation process, and for the monitoring of the therapeutic process associated with auditory processing disorders (APD). The differences and similarities in the acoustic coding between different types of stimuli in the context of APD remain unknown to this date.

METHODS

A total of 37 children aged between 7 and 11 years, with and without APDs (identified based on verbal and non-verbal tests), all with a suitable intelligence quotient with respect to their chronological age, were assessed. Components P1 and N1 were studied using verbal and non-verbal stimuli.

RESULTS

The comparison between stimuli in each group revealed that the control group had higher latency and amplitude values for speech stimuli, except for the P1 amplitude, while the group with APDs had different results with respect to the amplitudes of P1 and N1, yielding higher values for speech sounds. The differences between the groups varied according to the type of stimulus: the difference was in amplitude for the verbal stimulus and latency for the non-verbal stimulus.

CONCLUSION

The records of components P1 and N1 revealed that the children with APDs performed the coding underlying the detection and identification of acoustic signals, whether verbal and non-verbal, according to a different pattern than the children in the control group.

Intervention based on shared story reading: effect on low and high challenge reading and writing tasks

PURPOSE

to investigate the effectiveness of an intervention proposal based on shared story reading for reading comprehension, written narrative and word reading/writing.

METHODS

44 children were divided into two groups according to their performance in a reading comprehension test - The first group, G1, consisted of children with reading comprehension difficulty, and the second, G2, consisted of children who did not have difficulties. All children were evaluated regarding reading/writing isolated words, reading comprehension of sentences, and written narrative. After this evaluation, G1 children participated in an intervention program (15 meetings) that stimulated shared story reading. After this intervention, all children were reevaluated. Intra- and intergroup data were analyzed statistically by applying appropriate statistical tests, with the level of significance set at >0.05%.

RESULTS

after the intervention program, G1 children showed significant improvement in the variables evaluated. In the intergroup analysis, at the time of evaluation, G1 differed from G2 in reading/writing, reading comprehension, ability to correctly judge the verbs, and in textual coherence. At reassessment, G1 matched G2 in textual coherence and approached G2 in reading/writing isolated words and reading comprehension.

CONCLUSION

shared story reading promoted the development of low and high level reading and writing skills, being more effective for high-level strategies (example: written narrative). It is suggested that a specific program for orthographic questions be associated.

Development of language and arithmetic skills: risk and protective factors. Comparative cross-sectional study

BACKGROUND

In a literate society, linguistic/arithmetic performance is highly valued. Based on defined risk factors, strategies for promotion of better performance can be developed.

OBJECTIVE

To ascertain the risk and protective factors relating to development of language and arithmetic.

DESIGN AND SETTING

Observational comparative cross-sectional study at a public elementary school in Ribeirão Preto (SP), Brazil.

METHODS

A total of 66 children (41% females) attending first to fifth grades participated in this study. They were divided into two groups: G1, children classified as presenting language or arithmetic deficits; G2, average performance. Language (oral and written) and arithmetic skills were assessed through standardized tests. Variables relating to social skills, home environment resources and behavioral problems were assessed through standardized scales. Data on other variables (pre, peri and postnatal complications, maternal variables and others) were collected through interviews. The logistic regression technique with LASSO was used (α = 0.05).

RESULTS

Teenage pregnancy and consumption of psychoactive substances during pregnancy or complications during pregnancy were risk factors for performance regarding arithmetic and language. Higher schooling level for the mother was a protective factor in the development of arithmetic and language. Being female and having a history of otitis were risk factors for language. Altered social skills (responsibility and civility) and complaints of inattention were risk factor for arithmetic. Adequate linguistic development was a protective factor for the development of arithmetic.

CONCLUSION

The risk/protective factors included variables relating to the gestational period, mother's age when pregnant, mother's schooling, social skills, behavior and development issues.

Screening and diagnosis of learning disabilities/disorders - outcomes of interdisciplinary assessments

ABSTRACT Objective: to determine the occurrence of children with poor school performance and to investigate which intrinsic influences are most prevalent among them. Methods: a total of 104 children from the 1st grade to the 5th of elementary school participated in phase 1 (selection of children with poor school performance by a standardized test and based on average grade) and 56 of them (54%) were classified as having poor school performance. In phase 2 (differential diagnosis), 35 of these 56 children underwent multidisciplinary assessments and the results were submitted to a descriptive analysis. Results: out of the 35 children who completed phase 2, 18 (51%) were diagnosed with mood disorder (2 - 6% depression; 16 - 45% anxiety disorder/signs), 14 (40%) showed attention deficit disorder and hyperactivity, 1 (3%) showed specific language disorder and 1 (3%) showed specific learning disorder. Among the most prevalent changes in reading/writing/arithmetic dysortography (19 children - 54%) and the presence of non-literate children (10 - 29%) were observed. Conclusions: more than a half of the school-age children studied had learning deficits in written language and/or arithmetic, and the most prevalent intrinsic variables were internalizing disorders and the attention deficit/hyperactivity one.

Early undernutrition as a cause of changes in phonological processing skills

ABSTRACT Purpose: to determine whether undernutrition in the first years of life affects the phonological awareness skills, the phonological working memory and the school performance of children. Methods: the participants were children with a history of moderate/severe undernutrition during their first years of life (G1) who achieved nutritional recovery (n = 15). The performance of G1 in different cognitive tasks (phonological awareness at the syllable and phoneme level, phonological working memory - repetition of digits and pseudowords, and reading, writing and arithmetic activities) was compared to that of children with school difficulties (G2) (n = 15) and without school difficulties (G3) (n = 15), all eutrophic ones. Results: the performance of G1 was worse than that of the other two groups in all tasks evaluated (mean score of G1, G2 and G3 and p-values: phonological awareness: 31, 41, 57 - 0.01; repetition of direct order digits: 18, 23, 28 - 0.001; writing: 4, 10, 22 - 0.001; reading: 26, 45, 65-0.001; arithmetic: 4, 7, 11- 0.001). Conclusion: the results demonstrate that undernutrition affected the cognitive development, causing changes in important cognitive skills for the development of written language.

Variables associated with speech and language therapy time for aphasia, apraxia of speech and dysarthria

The most common acquired communication disorders are aphasia, dysarthria and apraxia of speech. Determining the factors associated with speech therapy time of adults with these disorders can further the understanding of the speech and language rehabilitation process within the public service and linked to the health education process.

Effects of working memory intervention on students with reading comprehension difficulties

ABSTRACT Purpose: to investigate the effectiveness of a working memory-based intervention proposal for reading comprehension. Methods: 43 children divided into two groups according to their performance in a reading comprehension test - G1: children with reading comprehension difficulty; G2: children with no difficulties. All the children were evaluated regarding reading, writing, sentence reading comprehension, and phonological working memory - PWM (repetition of pseudo-words and digits). After this evaluation, children from G1 participated in an intervention program (15 meetings) that stimulated the PWM. Following the intervention, all the children were reevaluated. The results were compared intra- and intergroup, and pertinent statistical tests were applied, by adopting the significance level lower than 0.05%. Results: after the intervention program, the children of G1 showed a significant improvement in all tests. In the intergroup analysis, at the time of evaluation, G1 was different from G2 in reading, writing and reading comprehension. In the reevaluation, G1 equaled G2 in reading and got closer to G2 in writing and reading comprehension. Conclusion: PWM training brought benefits to children with academic difficulties. Thus, these strategies could be used in the classroom, aiming to promote learning.

Memory performance, oral comprehension and learning process between children with attention deficit hyperactivity disorder and children with anxiety disorder

ABSTRACT Purpose: to compare aspects of memory, learning and oral comprehension between children with Attention Deficit Hyperactivity Disorder (ADHD) and children with Anxiety Disorder (AD). Methods: thirty-two children (7-10 years) were divided into: G1 - children diagnosed with ADHD, and G2 - children diagnosed with AD. The children were not under drug treatment. The tests applied assessed working memory (phonological loop and visuospatial sketch), learning, episodic memory and oral comprehension. Results: both groups showed changes in working memory for visuospatial sketch and phonological loop (worse performance in pseudowords in the ADHD group and digit-reversed order for children with AD), and in oral comprehension. Group comparison showed a statistically significant difference regarding the most complex level of the oral comprehension test and the repetition of nonwords with three syllables. Both groups showed a suitable performance in learning ability, however, the group of children with ADHD suffered from backward interference, with no memory consolidation, showing low episodic memory performance. Conclusion: children with ADHD and anxiety disorder showed various altered cognitive skills, although group comparison revealed that children with ADHD exhibited worse cognitive performance.

Characteristics of the emissive prosody of children with autism spectrum disorder

ABSTRACT Objective: to analyze the prosodic aspects of speech in children with Autism Spectrum Disorder. Methods: 21 children aged 3 to 6 years participated and were divided into three groups: Group 1 - children with Autism Spectrum Disorder; Group 2 - children with language delay; Group 3 - children with typical language development. Three judges performed a subjective evaluation of the emissive prosody (characterization of pitch, loudness, sentence stress, stressed syllable and others) of the children during interaction time (video recording and use of specific protocols). The equality of proportions test was applied for group comparison (α=0.01). Results: the prevalence of a history of delay for speaking the first words was high in Groups 1 and 2. Regarding the prosodic characteristics, all Group 1 children had difficulties in the use of the stressed syllable, and some in the accentuation of the sentence. On the other hand, no Group 3 children showed these changes and few Group 2 children presented excessively stressed syllable. Conclusion: inappropriate stressing of words seems to be one of the features in the differential diagnosis of verbal children with Autism Spectrum Disorder.

Relação entre o desempenho em aritmética e a memória de trabalho fonológica em crianças

RESUMO Objetivo Comparar os resultados da Memória de Trabalho - Alça Fonológica (MTAF) em crianças com dificuldades específicas em aritmética. Método O estudo foi realizado com 30 crianças, com idade entre sete e nove anos que frequentavam a segunda ou terceira série do Ensino Fundamental da rede pública de ensino. Foram excluídas da pesquisa as crianças com sinais sugestivos de perda auditiva, alterações neurológicas, baixo desempenho na prova de compreensão leitora ou em acompanhamento fonoaudiológico. As crianças incluídas na pesquisa foram submetidas ao subteste de aritmética do Teste de Desempenho Escolar para divisão em dois grupos (G1 e G2). O G1 foi composto por crianças com baixo desempenho em aritmética e o G2, por crianças com desempenho médio/superior em aritmética. Todas as crianças foram submetidas à avaliação da MTAF por meio da prova de repetição de palavras sem significado. Para análise estatística, foi utilizado o teste de Mann-Whitney, considerados significativos os valores de p-valor <0,05. Resultados Participaram do estudo 20 meninas e 10 meninos, com idade média de 8,7 anos. O G1 foi composto por 17 crianças e o G2, por 13 crianças. Houve diferença estatisticamente significativa entre os grupos estudados para a repetição de palavras sem significado com três e quatro sílabas, com pior desempenho para o G1. Conclusão Os resultados deste estudo fornecem suporte para a hipótese de que a alteração na MTAF está relacionada com dificuldades em aritméticas.

Adaptação transcultural do Communication Function Classification System para indivíduos com paralisia cerebral

RESUMO Objetivo: realizar a adaptação transcultural do Communication Function Classification System para a população brasileira e verificar a aplicabilidade da versão traduzida. Métodos: o estudo foi constituído de duas etapas, a primeira relacionada com o processo de tradução e adaptação transcultural por meio da tradução, análise semântica dos itens, e retrotradução do instrumento. A segunda, à testagem do instrumento, foi realizada em 40 pacientes com diagnóstico de paralisia cerebral. Resultados: a versão final recebeu a chancela da autora do instrumento original e foi publicada pela mesma, juntamente com a versão original e todas as demais traduções, no site http://cfcs.us. 60% (24) dos pacientes eram do sexo masculino e 40% (16) do feminino, as idades variaram entre dois anos e quatro meses à 28 anos e dois meses, e a idade média de 7,7 (±4,6). O instrumento foi de fácil e rápida aplicação, e todos os níveis de comunicação foram observados. Sendo que oito pacientes estavam no Nível I, nove no Nível II, dois no Nível III, treze no Nível IV e oito no Nível V. Conclusões: a versão traduzida e adaptada para o Português Brasileiro do CFCS possibilitou a classificação do desempenho da comunicação diária de indivíduos com Paralisia Cerebral em um dos cinco Níveis de Comunicação. Entretanto, para que seja amplamente utilizado em ambientes clínicos e de pesquisa, ainda há necessidade de trabalhos futuros que verifiquem a sensibilidade e a especificidade do mesmo, além da validação das propriedades psicométricas da versão brasileira do instrumento.

Principais alterações encontradas nas narrativas escritas de crianças com dificuldades em leitura/escrita

RESUMO Objetivo: analisar as produções escritas de crianças com dificuldades em leitura/escrita. Métodos: 171 crianças, matriculadas no 4º/5º do ensino fundamental constituíram dois grupos: G1 (n=50) - crianças sem dificuldades em leitura/escrita, G2 (n=121) - crianças com dificuldades nessas tarefas. Cada criança, após observar uma figura estímulo, deveria escrever um texto. Foi analisado a grafia, os erros ortográficos, as variáveis linguísticas e o conteúdo deste. Resultados: em G2 observou-se alterações em relação à grafia; maior percentual de ocorrência de erros ortográficos e de diversos tipos; mesma proporção no uso de substantivos, adjetivos e pronomes, porém dificuldade na conjugação verbal e no uso de advérbios temporais. Em relação ao conteúdo, apenas descreveram a cena e demonstraram vocabulário restrito e pouca criatividade. Conclusão: a produção escrita de crianças com dificuldade em leitura/escrita apresentou diversas falhas entre as quais: alterações na grafia, presença de erros ortográficos e limitação na construção de texto, restringindo-se a simples descrição do desenho estímulo, com pouca articulação de idéias e sem criação de personagens, local e tempo para a sua história. Este conjunto de falhas compromete a inteligibilidade do texto pelo leitor e demonstra que a elaboração escrita é uma tarefa complexa para essas crianças.

Deficits in working memory, reading comprehension and arithmetic skills in children with mouth breathing syndrome: analytical cross-sectional study

CONTEXT AND OBJECTIVE

Mouth breathing syndrome is very common among school-age children, and it is possibly related to learning difficulties and low academic achievement. In this study, we investigated working memory, reading comprehension and arithmetic skills in children with nasal and mouth breathing.

DESIGN AND SETTING

Analytical cross-sectional study with control group conducted in a public university hospital.

METHODS

42 children (mean age = 8.7 years) who had been identified as mouth breathers were compared with a control group (mean age = 8.4 years) matched for age and schooling. All the participants underwent a clinical interview, tone audiometry, otorhinolaryngological evaluation and cognitive assessment of phonological working memory (numbers and pseudowords), reading comprehension and arithmetic skills.

RESULTS

Children with mouth breathing had poorer performance than controls, regarding reading comprehension (P = 0.006), arithmetic (P = 0.025) and working memory for pseudowords (P = 0.002), but not for numbers (P = 0.76).

CONCLUSION

Children with mouth breathing have low academic achievement and poorer phonological working memory than controls. Teachers and healthcare professionals should be aware of the association of mouth breathing with children's physical and cognitive health.

Audiometric thresholds and auditory processing in children with early malnutrition: a retrospective cohort study

CONTEXT AND OBJECTIVE

Malnutrition is one of the causes of changes in cell metabolism. The inner ear has few energy reserves and high metabolism. The aim of this study was to analyze whether malnutrition at an early age is related to impairment of auditory processing abilities and hearing abnormalities.

DESIGN AND SETTING

Retrospective cohort study conducted in a tertiary public hospital.

METHODS

45 children participated, divided as follows: G1, children diagnosed with malnutrition in their first two years of life; G2, children without history of malnutrition but with learning difficulties; G3, children without history of malnutrition and without learning difficulties. Tympanometry, pure-tone audiometry and the Staggered Spondaic Word (SSW) test (auditory processing) were performed. Statistical inferences were made using the Kruskal-Wallis test (α = 5%) and the test of equality of proportions between two samples (α = 1.7%).

RESULTS

None of the 45 children participating in this study presented hearing deficiencies. However, at six of the eight frequencies analyzed, the children in G1 presented hearing thresholds lower than those of the other groups. In the auditory processing evaluation test, it was observed that 100% of the children in G1 presented abnormal auditory processing and that G1 and G2 had similar proportions of abnormalities (P-values: G1/G2 = 0.1; G1/G3 > 0.001; G2/G3 = 0.008).

CONCLUSIONS

Malnutrition at an early age caused lowering of the hearing levels, although this impairment could not be considered to be a hearing deficiency. Every child in this group presented abnormalities in auditory processing abilities.

Memory, learning, and participation of the cholinergic system in young rats exposed to environmental enrichment

The present study demonstrates the consequences of animal exposure to an enriched environment compared to animals living in a standard environment regarding learning and space memory. Male albino Wistar rats were exposed to an enriched environment for 4 weeks after the lactation period and tested in the Morris water maze in the distal and proximal clue version and in the arena. In the former test, the animals were tested at 50 days of age with 12 daily trials on two consecutive days. At the end of each session, scopolamine at the dose of 0.6 mg/kg/ml or saline solution was injected intraperitoneally. Twenty-eight days after the first phase, a new test consisting of a single trial was held (retest). An independent group of animals receiving no drug was subjected to the arena test and to the proximal clue version of the Morris maze. In the distal clue version the results did not show differences between groups in the first phase of the experiment. After 28 days (retest), the animals reared in a standard environment and treated with scopolamine exhibited a significant increase in latency compared to the group receiving the same drug and stimulated and to the group receiving saline. The arena data demonstrated a significant increase in exploratory activity in the group of animals reared in an enriched environment. The proximal clue version of the Morris maze did not show differences between groups. The results of the present study indicate that animals exposed to environmental enrichment react less to the amnesic effects of scopolamine and show an increase in exploratory activity.

Language aspects of children infected with HIV

PURPOSE: to assess the lexical proficiency and the incidence of phonologic disorders in the language of children infected with HIV. METHOD: the study population consisted of 31 children between three and seven year-old. For evaluation purposes the Test of Infantile Language - ABFW was applied in the areas of phonology and vocabulary. RESULTS: the results obtained were analyzed according to the clinical criteria for the classification of the disease proposed by the CDC and regarding the immunological profile and the viral burden using the Mann-Whitney test for statistical analysis. In the vocabulary evaluation, 100% of the children presented an inappropriate response for their age in at least two distinct conceptual fields. In the phonologic evaluation, 67.7% of the assessed children were considered to be affected by some phonologic disorder. When we compared adequate and inadequate results of phonologic evaluation to the clinical and immunological parameters of AIDS such as clinical classification (p=0,16), CD4 count (p=0,37) and viral burden (p=0,82), we did not detect a statistically significant relation between language alterations and disease severity. CONCLUSION: this research has shown that the studied group presents a high risk for language disorders and that constant phonoaudiological follow-up is essential to identify the alterations in early stage.

Phonological awareness abilities of a child with acquired immunodeficiency syndrome before and after speech therapy

The aim of the present study was to characterize the phonological awareness abilities of a child with Acquired Immunodeficiency Syndrome (AIDS) before and after speech-language therapy. The participant was a 6-year-old girl, first-grade Elementary School student, with AIDS acquired by vertical transmission. The child's phonological awareness abilities were evaluated using the Instrument of Sequential Evaluation of Phonological Awareness (CONFIAS). After this first evaluation, a closed therapeutic program (15 sessions) for phonological awareness was developed, consisting of activities for syllabic and phonemic levels. The CONFIAS was reapplied in the last session in order to investigate therapy effectiveness. In the pre-therapy assessment, the child scored 18 points in syllable tasks and 1 point in phoneme tasks, with a total score of 19 points. In the post-therapy assessment, the child scored 26 points in syllable tasks and 11 points in phoneme tasks, with a total score of 37 points. This study allowed us to characterize the performance of a child with AIDS in tasks of phonological awareness and the effectiveness of the therapeutic program. The score obtained before therapy was much lower than expected for the child's age, and presented significant improvement after speech-language therapy. Thus, professionals working with this population must be aware of therapeutic programs that approach phonological processing abilities in addition to other aspects.

Aspectos perinatais, cognitivos e sociais e suas relações com as dificuldades de aprendizagem

OBJETIVO: analisar quais aspectos perinatais, cognitivos e sociais são fatores de risco para dificuldade s de aprendizagem em leitura, escrita e aritmética. MÉTODO: participaram desse estudo 45 crianças (média de 8,3 anos). Preliminarmente, os responsáveis de cada criança responderam a um questionário para coleta de informações a respeito da gestação, do nascimento e do desenvolvimento da criança, além dos aspectos sociais que a envolvem. O desempenho das crianças em tarefas de leitura, escrita, aritmética, consciência fonológica, memória fonológica e processamento auditivo foram avaliados. Para a análise das relações entre as variáveis independentes (fatores perinatais, cognitivos e sociais) e as dependentes (leitura, escrita e aritmética) utilizou-se como método estatístico a Regressão Logística. RESULTADOS: a consciência fonológica foi fator de risco para a leitura (OD = 42; p-valor 0,02), para a escrita (OD = 10,8; p-valor 0,01) e para a aritmética (OD = 42; p-valor 0,002). A memória fonológica foi significante para a leitura (OD = 24; p-valor 0,04) e para a aritmética (OD = 4; p-valor 0,04). Observa-se também, que a escolaridade materna elevada funciona como proteção para problemas escolares (OD = 0,3; p-valor >0,001) ou para intensificar essas dificuldades (OD = 2,3; >0,001). Não houve relação entre peso ao nascimento, prematuridade e outras variáveis com desempenho escolar. CONCLUSÕES: crianças que possuem alterações de consciência fonológica e de memória fonológica ou, que são filhas e/ou convivem com pessoas de baixa escolaridade, são crianças com maiores chances de apresentarem dificuldades de aprendizagem.

Characterization of language and phonological working memory in patients with myoclonic astatic epileptic syndrome

The course of myoclonic astatic epileptic syndrome (MAES) is variable and little information is available about cortical functions in the presence of the disease. The objective of the present study was to assess the phonological working memory (PWM) and the verbal language of six patients between 8 and 18 years old, on treatment for at least 5 years, and good control of seizures, diagnosed in the Service of Epilepsy of Hospital of Clinics of Ribeirão Preto, São Paulo University in Brazil. The Test of Repetition of Meaningless Words was used to assess PWM. Video-recorded of language samples were collected during spontaneous and directed activities for the study of verbal language and pragmatics. A qualitative analysis showed that all patients presented deficits in the execution of the PWM test and only one patient showed poor mastery of all aspects studied. These finds contribute to strategies of treatment for language problems of patients with MAES, focusing on PWA.

Effects of early protein malnutrition and scopolamine on learning and memory in the Morris water maze

The present study investigated the effects of early protein malnutrition on the spatial learning and memory processes. The consequences of malnutrition for the cholinergic system were evaluated by comparing the performance of malnourished and control animals in the Morris water maze after treatment with scopolamine. The learning test consisted of placing the animal in the maze to escape to a submerged platform with 12 trials per day for two consecutive days. After 24 trials, the platform was removed, the rats were placed in the maze and the time spent by them in each quadrant was recorded. After 28 days the animals were tested in a single trial to verify the retention of the spatial information. In the first Experiment, scopolamine (0.0, 0.2, 0.4 and 0.6 mg/kg per ml. i.p.) was administered 20 min before the experimental sessions. In the second experiment, a dose of 0.6 mg/kg was administered after the sessions, during the period in which learning consolidation occurs. In the first experiment, there was a significant effect of the drug, with scopolamine impairing, learning in both nutritional conditions. In the saline condition, control animals presented a better performance when compared with malnourished animals. However, 28 days later, both groups increased their latencies. With 0.2 and 0.4 mg/kg of scopolamine, the performance of both nutritional groups was similar and with 0.6 mg/kg malnourished animals performed better than controls. In the second experiment, malnourished animals were also less reactive to the effects of scopolamine, resulting in lower impairments as compared to control animals. These data suggest long-term changes in learning and memory as the result of changes produced by protein malnutrition in the cholinergic neurotransmitter system.

Anxiolytic-like effects of short-term postnatal protein malnutrition in the elevated plus-maze test

Given that protein malnutrition induces structural, neurochemical and functional changes in the CNS, the present study aimed to investigate the effects of short-term early protein malnutrition on the behavior and reactivity to diazepam (DZ) in the elevated plus-maze test (EPM). Male Wistar rats (n=176) from well-nourished (16%-protein) or malnourished litters (6%-protein) were distributed in five different groups: W (well-nourished), M7 (malnourished for 7 days), M14 (malnourished for 14 days), M21 (malnourished for 21 days) and M28 (malnourished for 28 days) since birthday. EPM results showed that the longer the exposition to the deficient diet, the lower the anxiety of malnourished animals, a result similar to that produced by the treatment with DZ. This anxiolytic-like effect suggested that short-term malnutrition may affect neural and/or neurochemical systems believed to underlie behavioral expression in anxiogenic experimental situations.

Effects of different malnutrition techniques on the behavior of rats tested in the elevated T-maze

The influence of different malnutrition techniques on the behavior of adult animals was investigated in the elevated T-maze (ETM). Control litters (C) were composed by eight pups constantly kept with their mother and fed by a 16%-protein diet ad libitum; protein malnutrition litters (PM) were fed by a 6%-protein diet; protein-calorie malnutrition litters (PCM) were fed with 50% of the 16%-protein diet ingested by C litters; malnutrition by increase in the size of the litter (LLM-number of pups was twice the number of pups in C litters), and malnutrition by separation (SM-litters spent half of the day with non-lactating females). After weaning, all groups received lab chow diet until the test day (70th day). During the test were recorded the basal, avoidance 1, avoidance 2 and escape latencies. The data showed that PM, PCM, LLM and SM animals showed lower increases in avoidance latencies, when compared to their control groups. However, malnutrition did not affect escape latencies. The nature of these alterations seems to be nutritional, as the extra-nutritional factors (i.e. maternal care) differ a lot among the malnutrition techniques. These results suggest that malnutrition, irrespective of the technique, altered the neural mechanisms believed to control defensive behaviors in the ETM.

Early postnatal protein malnutrition affects learning and memory in the distal but not in the proximal cue version of the Morris water maze

Learning and memory of early postnatal protein malnourished rats were investigated in the Morris water maze. During the lactation period (21 days) each litter (mother plus six male and two female pups) was provided with 16% (well-nourished) or 6% (malnourished) protein diets. After weaning, rats remained on the same diet until 49 days of age. From day 50 on all animals were fed a commercial lab chow. Experiments started on day 70. In experiment I (proximal cue version) the animals were trained to escape from water to a visible platform (3 cm above the water level) in six trials daily for four consecutive days, completing 24 trials. In experiment II (distal cue version) the animals were trained to escape from water to a submerged platform using the same procedure as in experiment II. After the 24th trial, the platform was removed and the animals were submitted to a 60-s trial (probe trial). Seven and twenty-eight days after training, the retention test was conducted in one 180-s trial. The results showed no impairment of the learning or memory of malnourished animals tested in the proximal cue version but an increased latency and distance traveled to find the submerged platform in the distal cue version of the procedure. In the distal cue version the malnourished animals also showed increased latency to find the platform 7 and 28 days after the test training. No difference due to diet was found in the probe trial test indicating that, once the task is acquired, malnourished rats can manage extra-maze cues as easily as well-nourished rats. It is suggested that the present results can be due to alterations produced by protein malnutrition in the hippocampal formation or also to reflect the higher emotionality of rats following early malnutrition, specially considering the fact that postnatally malnourished animals are more reactive to unpleasant or aversive stimuli as cold water.