Search results for "Amnesia"
showing 10 items of 54 documents
Hypericum Extract and Hyperforin: Memory-Enhancing Properties in Rodents
2001
Effects of a Hypericum extract in therapeutic use and hyperforin sodium salt were evaluated in rat and mouse avoidance tests. In a conditioned avoidance response (CAR) test on the rat, oral daily administration of hyperforin (1.25 mg/kg/day) or of the extract (50 mg/kg/day) before the training sessions considerably improved learning ability from the second day onwards until the day 7. In addition, the memory of the learned responses acquired during 7 consecutive days of administration and training was largely retained even after 9 days without further treatment or training. The observations made using different doses indicate that these learning-facilitating and/or memory-consolidating effe…
Selective sparing of face learning in a global amnesic patient
2001
Objective - To test the hypothesis that visual memory for faces can be dissociated from visual memory for topographical material. Method - A patient who developed a global amnesic syndrome after acute carbon monoxide poisoning is described. A neuroradiological examination documented severe bilateral atrophy of the hippocampi. Results - Despite a severe anterograde memory disorder involving verbal information, abstract figures, concrete objects, topographical scenes, and spatial information, the patient was still able to learn previously unknown human faces at a normal (and, in some cases, at a higher) rate. Conclusions - Together with previous neuropsychological evidence documenting selecti…
Preclinical dementia: an Italian multicentre study on amnestic mild cognitive impairment
2006
<i>Background:</i> Different rates and cognitive predictors of conversion to dementia have been reported in subjects with different kinds of mild cognitive impairment (MCI). <i>Methods:</i> A prospective, 24-month follow-up study, involving 269 subjects who strictly fulfilled criteria for the amnestic MCI. <i>Results:</i> Conversion rate to dementia was 21.4% per year. Seventy-nine out of the 83 individuals who developed dementia were affected by probable Alzheimer’s disease (AD). Among others, at the 24-month follow-up 24.1% were still affected by amnestic MCI, 13.3% had changed their neuropsychological profile of impairment and 17.2% were cognitively no…
Carnitine congener mildronate protects against stress- and haloperidol-induced impairment in memory and brain protein expression in rats.
2014
The present study investigates the efficacy of mildronate, a carnitine congener, to protect stress and haloperidol-induced impairment of memory in rats and the expression of brain protein biomarkers involved in synaptic plasticity, such as brain-derived neurotrophic factor (BDNF), acetylcholine esterase and glutamate decarboxylase 67 (GAD67). Two amnesia models were used: 2h immobilization stress and 3-week haloperidol treatment. Stress caused memory impairment in the passive avoidance test and induced a significant 2-fold BDNF elevation in hippocampal and striatal tissues that was completely inhibited by mildronate. Mildronate decreased the level of GAD67 (but not acetylcholine esterase) e…
Movements Execution in Amnestic Mild Cognitive Impairment and Alzheimer’s Disease
2007
We evaluated the relationship between motor and neuropsychological deficits in subjects affected by amnestic Mild Cognitive Impairment (aMCI) and early Alzheimer’s Disease (AD). Kinematics of goal-directed movement of aMCI and AD subjects were compared to those of age-matched control subjects. AD showed a slowing down of motor performance compared to aMCI and controls. No relationships were found between motor and cognitive performances in both AD and aMCI. Our results suggest that the different motor behaviour between AD and aMCI cannot be related to memory deficits, probably reflecting the initial degeneration of parietal-frontal circuits for movement planning. The onset of motor dysfunct…
The neuropsychiatric profile of Parkinson's disease subjects with and without mild cognitive impairment
2012
Neuropsychiatric symptoms (NPS) are common clinical features of Parkinson's disease (PD). However, NPS profiles in PD subjects with mild cognitive impairment (MCI) have scarcely been investigated. We aimed to describe the NPS profiles of non-demented PD subjects with and without MCI. A total of 410 non-demented PD subjects were included. Of these, 164 were cognitively normal PD subjects (PD-cn), 142 PD had amnestic MCI (PD-aMCI), and 104 had PD with non-amnestic MCI (PD-naMCI). NPS were evaluated in accordance with the Neuropsychiatric Inventory (NPI). PD-aMCI subjects revealed the highest NPS burden, followed by PD-naMCI and then PD-cn. Overall, the most common NPS in PD-MCI were in order:…
Misidentification Delusions : prevalence in different types of dementia and validation of a structured Questionnaire
2016
International audience; Misidentification delusions (MDs) are considered relatively rare psychopathologic phenomena that may occur within the context of psychiatric or neurological conditions. The purpose of this study was to assess the prevalence of MD in different types of dementia, correlate the presence of MD with demographic and clinical variables, and validate a specific questionnaire. We examined 146 subjects with Alzheimer disease, 21 with Lewy body dementia, 6 with frontotemporal dementia, and 13 with vascular dementia (subcortical type), who were consecutively enrolled in the study from 2 Memory Clinics. Patients had a mean age of 78.7±6.4 years and an Mini-Mental State Examinatio…
When the amnestic mild cognitive impairment disappears: characterisation of the memory profile
2009
BACKGROUND/OBJECTIVES: Subjects affected by mild cognitive impairment (MCI) may improve during the observation period. This is the first study investigating qualitative features of memory deficits in subjects affected by reversible MCI [reversible cognitive impairment (RCI)]. METHODS: Baseline cognitive and memory performances of 18 subjects affected by amnestic MCI who had normalized cognitive performances at follow-ups were compared with those of 76 amnestic MCI subjects who still showed impaired cognitive performances at the 24-month follow-up (MCI) and with those of a group of 87 matched control subjects (normal controls). RESULTS: Compared with normal controls the memory deficit in the…
The contribution of acetylcholine and dopamine to subprocesses of visual working memory--what patients with amnestic mild cognitive impairment and Pa…
2014
Attentional selection, i.e. filtering out of irrelevant sensory input and information storage are two crucial components of working memory (WM). It has been proposed that the two processes are mediated by different neurotransmitters, namely acetylcholine for attentional selection and dopamine for memory storage. However, this hypothesis has been challenged by others, who for example linked a lack in dopamine levels in the brain to filtering deficits. Here we tested the above mentioned hypothesis in two patient cohorts which either served as a proxy for a cholinergic or a dopaminergic deficit. The first group comprised 18 patients with amnestic mild cognitive impairment (aMCI), the second 22…
Neonatal representation of odour objects: distinct memories of the whole and its parts
2014
Extraction of relevant information from highly complex environments is a prerequisite to survival. Within odour mixtures, such information is contained in the odours of specific elements or in the mixture configuration perceived as a whole unique odour. For instance, an AB mixture of the element A (ethyl isobutyrate) and the element B (ethyl maltol) generates a configural AB percept in humans and apparently in another species, the rabbit. Here, we examined whether the memory of such a configuration is distinct from the memory of the individual odorants. Taking advantage of the newborn rabbit's ability to learn odour mixtures, we combined behavioural and pharmacological tools to specifically…