Following a cortical injury, neurons in areas near and connected to the site of injury begin to degenerate. The observed neuronal death may contribute to the severity of the observed behavioral impairments. The purpose of the present study was to examine if progesterone, a hormone known for its effectiveness at reducing cerebral edema, could protect against secondary neuronal death and facilitate the acquisition of an avoidance learning task in an ablation model of cortical injury. Rats served as sham controls or received bilateral ablation of the medial prefrontal cortex followed by a 10-day regimen of progesterone (4 mg/kg) or oil vehicle (1 ml/kg) beginning 1 h after cortical lesions. Progesterone-treated lesion rats showed a significant facilitation of avoidance learning compared to oil- treated lesion controls. In addition, progesterone-treated lesion animals did not differ from either progesterone- or oil-treated sham controls in avoidance learning. Anatomical analysis revealed that progesterone treatment decreased the amount of neuronal death seen in the striatum and the mediodorsal nucleus of the thalamus. The findings are consistent with the notion that progesterone is an effective neuroprotective agent and suggest that the hormone can reduce the behavioral impairments associated with frontal cortical ablation injury.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18174号 / 医博第3894号 / 新制||医||1003(附属図書館) / 31032 / 京都大学大学院医学研究科医学専攻 / (主査)教授 金子 武嗣, 教授 髙橋 良輔, 教授 河野 憲二 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20806号 / 医博第4306号 / 新制||医||1025(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 井上 治久, 教授 髙橋 良輔, 教授 江藤 浩之 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

A review of anatomical and behavioural studies of the limbic system suggests that some structures which Papaz proposed as the central mechanism of emotion might be involved in food hoarding behaviour. Various structures in Papez· circuit were destroyed surgically and observations were taken on subsequent changes in food hoarding behaviour. In addition, observations were made on nest building behavior and on avoidance performance. It was found that rats with bilateral damage to the mammillothalamic tract and mammillary body were severely depressed in hoarding and avoidance behaviour. Septal damage caused a less severe deficit in both behaviours while hippocampal, domical or thalamic damage did not have a significant effect. A pilot study of hoarding behaviour in the hamster was carried out. / Thesis / Master of Arts (MA)

No description available.

[pt] O Comprometimento cognitivo vascular subcortical (CCVs) caracteriza-se, do ponto de vista cognitivo, por déficits em funções executivas em seus estágios iniciais, levando a dificuldades funcionais precoces na população acometida. Contudo, dados da literatura indicaram que a condição é frequentemente subdiagnosticada, o que pode ser atribuído, dentre outras razões, à falta de instrumentos de rastreio acurados para a condição, cujas características clínicas diferem dos quadros neurodegenerativos. Esta escassez foi evidenciada pela revisão sistemática realizada como parte do presente trabalho. O Teste Breve de Memória e Funções Executivas (BMET) foi desenvolvido por Brookes e cols. (2012) especificamente para a detecção destes quadros clínicos. O objetivo desta dissertação foi discorrer sobre o CCVs e adaptar o BMET para o uso na população acima dos 60 anos do Brasil. Para tanto, seguiram-se etapas de tradução, avaliação de juízes de linguística e de neuropsicologia, avaliação por representante do público-alvo, retrotradução e, por fim, aplicação à amostra. Foi conduzido um estudo piloto para verificar a aplicabilidade e fornecer dados psicométricos preliminares do teste. Conclui-se que o BMET é de simples e rápida aplicação, podendo ser administrado por diferentes profissionais da saúde e possivelmente adequado à atenção primária em saúde. Considerando o contexto atual de um rápido envelhecimento populacional e do consequente aumento na prevalência de agravos associados às faixas etárias avançadas, tais como os transtornos neurocognitivos, é de grande relevância a detecção precoce do CCVs visando ao planejamento de intervenções e medidas de profilaxia secundária, contribuindo assim, para a qualidade de vida da população idosa. / [en] Subcortical Vascular Cognitive Impairment (sVCI) is characterized, upon a cognitive perspective, by the presence of dysexecutive function in its initial stages, leading to early functional difficulties for sufferers of this condition. However, data has indicated that it is often underdiagnosed, which could be attributed to the lack of accurate screening tools for the disorder. This shortcoming has been evidenced by a systematic review conducted as part of the current project. The Brief Memory and Executive Test (BMET) has been specifically developed by Brookes et al. (2012) for the detection of sVCI. This thesis aimed to discuss about sVCI and to adapt BMET for use in subjects over 60 years old from Brazil. For this purpose, consecutive stages, comprising translation, evaluation by experts in linguistics and neuropsychology, assessment by representant of the target population, retro-translation and, finally, application to an older sample, have been performed. A pilot study has been carried out to analyze the applicability and to draw preliminary information about psychometric properties of the scale. In conclusion, BMET has revealed to be easy and rapid to administer, feasible to be applied by different categories of health practitioners and possibly adequate for primary health settings. Considering the current context of a fast population aging and a rise in the prevalence of conditions associated with late-life, such as neurocognitive disorders, it is relevant to detect sVCI in its early stages, so that therapeutic and secondary preventive strategies could be planned, which could impact on the quality of lives of older population.

Quantitative magnetic resonance imaging (MRI) was used to assess global and regional cerebral volumes in patients with a clinical diagnosis of subcortical vascular dementia (VD) and Alzheimer’s disease (AD). Whole brain volume, cerebrospinal fluid volume, volumes of the temporal, frontal and parietal lobes, the cerebellum and the amygdala-hippocampus complex were determined using a personal computer-based software. Seventeen patients with VD, 22 patients with AD and 13 healthy controls were included. Analysis of covariance using age as covariate demonstrated significant mean differences between controls and dementia groups with respect to all morphological parameters. However, apart from the volume of the cerebellum no significant volumetric differences were found between VD and AD. These results indicate that MRI-based volumetry allows differentiation between AD or VD from normal controls and that measurement of cerebellar volume may be of use to separate vascular and degenerative dementia. However, since the distribution of cerebral atrophy in both dementia groups is very similar, it is suggested that the atrophic changes are not specific to the underlying cause but rather reflect the selective vulnerability of neuronal structures. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

No description available.

This thesis first explored the effects of concurrent spatial attention and working memory task performance on over-ground gait in healthy young and older adults. It then compared over-ground gait parameters and working memory performance in mild Alzheimer’s Disease (AD) and normal controls (NC) and investigated costs of dual-tasking on working memory performance and cadence during treadmill walking at preferred walking speed in the two groups. Furthermore, it explored these differences in AD and NC groups in relation to their subcortical hyperintensities (SH) that were rated using standardized scales on MRI. Reaction times and accuracy on working memory performance measures were collected under single and dual task conditions. Over-ground gait parameters were measured on an automated walkway. Costs of dual-tasking on gait parameters and working memory performance were measured at a constant velocity on a treadmill. The hypotheses that working memory influences gait performance and that a higher SH burden negatively influences over-ground gait and costs of dual-task conditions, were supported in a series of experiments. Gait slowed down while performing working memory and spatial attention tasks in young and older adults. Patients with mild AD, compared to NC, had a slower gait velocity, shorter stride length and lower cadence on the walkway. When the two groups were subdivided into higher and lower SH groups based on their median SH score, the NC group with lower SH burden walked significantly faster with a higher cadence and a longer stride length than the other three groups. Lastly, a higher SH burden negatively influenced working memory performance in NC while in mild AD patients, it had negative influences on adaptive changes in gait while dual-tasking. These results suggest that, in dual-task condition, SH interfere with processing speed in NC and on gait in AD. These findings provide new insights in to tradeoffs during dual tasking in relation to cerebrovascular disease. This has ecological implications because of the prevalence of small vessel disease in aging and dementia, may impact on predicting falls in AD.

This thesis first explored the effects of concurrent spatial attention and working memory task performance on over-ground gait in healthy young and older adults. It then compared over-ground gait parameters and working memory performance in mild Alzheimer’s Disease (AD) and normal controls (NC) and investigated costs of dual-tasking on working memory performance and cadence during treadmill walking at preferred walking speed in the two groups. Furthermore, it explored these differences in AD and NC groups in relation to their subcortical hyperintensities (SH) that were rated using standardized scales on MRI. Reaction times and accuracy on working memory performance measures were collected under single and dual task conditions. Over-ground gait parameters were measured on an automated walkway. Costs of dual-tasking on gait parameters and working memory performance were measured at a constant velocity on a treadmill. The hypotheses that working memory influences gait performance and that a higher SH burden negatively influences over-ground gait and costs of dual-task conditions, were supported in a series of experiments. Gait slowed down while performing working memory and spatial attention tasks in young and older adults. Patients with mild AD, compared to NC, had a slower gait velocity, shorter stride length and lower cadence on the walkway. When the two groups were subdivided into higher and lower SH groups based on their median SH score, the NC group with lower SH burden walked significantly faster with a higher cadence and a longer stride length than the other three groups. Lastly, a higher SH burden negatively influenced working memory performance in NC while in mild AD patients, it had negative influences on adaptive changes in gait while dual-tasking. These results suggest that, in dual-task condition, SH interfere with processing speed in NC and on gait in AD. These findings provide new insights in to tradeoffs during dual tasking in relation to cerebrovascular disease. This has ecological implications because of the prevalence of small vessel disease in aging and dementia, may impact on predicting falls in AD.