5 research outputs found
Exploring mechanisms that affect retrograde memory for public events in amnestic mild cognitive impairment: A longitudinal update
: Here, we examined mechanisms that affect retrograde memory in amnestic mild cognitive impairment (a-MCI) as a function of longitudinal clinical outcome. 8 a-MCI who converted to Alzheimer's dementia (AD) during the subsequent 3-year follow-up (converter a-MCI) and 10 a-MCI who remained clinically stable during the same period (stable a-MCI) were compared at the baseline evaluation (i.e., when they were diagnosed as a-MCI) using a remote memory questionnaire for public events that allows disentangling the differential contribution of storage and retrieval mechanisms to performance accuracy. Results suggest that deficits in remote memory are primarily explained by impaired retrieval abilities in stable a-MCI and by impaired storage in converter-to-AD a-MCI. This distinction between retrograde amnesia due to defective trace utilisation in stable a-MCI and trace storage in converter a-MCI is consistent with the temporal unfolding of declining anterograde memory over the course of disease progression to AD
The diagnostic usefulness of experimental memory tasks for detecting subjective cognitive decline: Preliminary results in an Italian sample
Objective: Subjective cognitive decline (SCD) was recently proposed as an early risk factor for future mild cognitive impairment and Alzheimer's disease (AD). In this study, we investigated the sensitivity of novel neuropsychological testing paradigms (which have been proposed as potentially challenging tools for the identification of preclinical AD) in capturing the subtle cognitive changes leading to SCD but not objectively detected by traditional tests. Method: The performances of 18 patients with SCD and 15 healthy individuals with no worries of cognitive decline (healthy controls [HC]) was compared on demanding tasks that investigated, respectively, associative memory, memory binding, spatial pattern separation processes and semantic memory. The diagnostic utility of these tests in capturing the subtle cognitive changes associated with SCD and possible relationships with SCD-related worries were investigated. Results: No significance between-group difference was found on the standard neuropsychological tests. Conversely, the performance of patients with SCD and HC differed significantly on specific indexes derived from experimental tasks assessing face-name associative memory and spatial pattern separation. Moreover, these measures correctly classified group membership with good overall accuracy (between 79% and 82%) and were significantly associated with self-perceived memory functioning. Conclusions: Our preliminary findings suggest that specific measures derived from demanding cognitive paradigms could be sensitive neuropsychological indexes for detecting the subtle cognitive impairment associated with SCD. These observations could be useful for further refining cognitive assessment aimed at early detection of AD
Forgetting rate for the familiarity and recollection components of recognition in amnestic mild cognitive impairment: A longitudinal study
Here we aimed to investigate the rate of forgetting of the familiarity and recollection components of recognition in patients at the onset of medial temporal lobe (MTL) pathology and destined to convert to Alzheimer's disease (AD). For this purpose, we conducted a longitudinal study of 13 patients who were diagnosed with amnestic mild cognitive impairment (a-MCI) at the first assessment and followed-up for 3 years. During this time, five patients converted to AD and eight remained in a stable condition of cognitive impairment. A group of 15 healthy subjects were enrolled as the control group (HC). In order to separately quantify the contribution of recollection and familiarity to recognition memory performance, the experimental sample was submitted to a modified version of Huppert and Piercy's procedure that included a Remember/Know paradigm. Data demonstrated that both stable and converter a-MCI patients forgot memory traces relative to the familiarity components of recognition at the same rate as HC. Conversely, converter a-MCI patients showed accelerated long-term forgetting specifically for the recollection component of recognition compared to stable a-MCI and HC. This is the first empirical demonstration that familiarity and recollection components of declarative memory are subject to different rates of forgetting in a-MCI patients as a function of their longitudinal clinical outcome. Our finding of accelerated long-term forgetting of the recollection component of recognition disclosed by converter a-MCI patients suggests that atrophy in the MTL not only interferes with the storage aspects but also disrupts the consolidation of memory traces
Effect of Dual-Task Motor-Cognitive Training in Preventing Falls in Vulnerable Elderly Cerebrovascular Patients: A Pilot Study
Falling is a frequent and major clinical problem among older adults, as well as in patients with chronic cerebrovascular diseases (CVD). At present, sequential (mixed) and simultaneously (dual-task) motor-cognitive trainings are the best approaches to affording patients more autonomy in their everyday motor independence while reducing fall risks and consequences. The objective of this study was to evaluate the efficacy of an advanced and innovative dual-task motor-cognitive rehabilitation program on fall risks in vulnerable older persons with chronic CVD. To this purpose, 26 consecutive older fallers with chronic CVD were recruited, and completed a mixed motor-cognitive or a dual-task motor-cognitive training program. Each patient also underwent two test evaluations to assess balance, gait, fear of falling, and walking performance at pre-and post-intervention. We found that our experimental motor-cognitive dual-task rehabilitation program could be an effective method to improve walking balance, gait, walking speed, and fear of falling, while reducing the risk of falls in older people with chronic CVD. Furthermore, results show that the simultaneous motor-cognitive training is more effective than the sequential motor-cognitive training. Therefore, our study brings innovative data, which can contribute positively to the management of this population