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    vessela stamenova

    Repetition-lag memory training was developed to increase individuals' use of recollection as opposed to familiarity in recognition memory. The goals... more
    Repetition-lag memory training was developed to increase individuals' use of recollection as opposed to familiarity in recognition memory. The goals of this study were to examine the feasibility of repetition-lag training in patients with chronic stroke and to explore whether the training might show suggestions of transfer to non-trained tasks. Quasi-experimental. Patients (n = 17) took part in six repetition-lag training sessions and their gains on the training and non-trained tasks were compared to those of age-matched healthy controls (n = 30). All but two patients completed the training, indicating that the method is feasible with a wide range of stroke survivors. The amount patients gained on the training task was similar to that of healthy controls (that is, the Group × Time interactions were by-and-large not significant), suggesting that stroke survivors might benefit to the same degree as healthy adults from this training. Both groups showed some indication of transfer to the non-trained backward digit span task and visuospatial memory. These findings show that repetition-lag memory training is a possible approach with stroke survivors to enhance recollection. Further research on the method's efficacy and effectiveness is warranted.
    Whereas source memory involves remembering from whom you have heard something, destination memory involves remembering to whom you have told something. Despite its practical relevance, destination memory has been studied little. Recently,... more
    Whereas source memory involves remembering from whom you have heard something, destination memory involves remembering to whom you have told something. Despite its practical relevance, destination memory has been studied little. Recently, two reports suggested that generally destination memory should be poorer than source memory, and that it should be particularly difficult for older people. We tested these predictions by having young and older participants read sentences to two examiners (destination encoding) and listen to sentences read by two examiners (source encoding), under intentional (Experiment 1) or incidental encoding (Experiments 2 and 3). Only in Experiment 3 (in which cognitive demands during destination encoding were increased) was destination memory significantly poorer than source memory. In none of the experiments were older adults inferior to the young on destination or source memory. Destination- and source-memory scores were significantly correlated. Item memory was consistently superior for sentences that had been read out loud (during destination encoding) versus those that had been heard (during source encoding). Destination memory needs not always be poorer than source memory, appears not to be particularly impaired by normal ageing and may depend on similar processes to those supporting source memory.
    Cerebral small vessel disease (CSVD) is a highly prevalent condition associated with diffuse ischemic damage and cognitive dysfunction particularly in executive function and attention. Functional brain imaging studies can reveal... more
    Cerebral small vessel disease (CSVD) is a highly prevalent condition associated with diffuse ischemic damage and cognitive dysfunction particularly in executive function and attention. Functional brain imaging studies can reveal mechanisms of cognitive impairment in CSVD, although findings are mixed. A systematic review integrating findings from functional magnetic resonance imaging and electroencephalography in CSVD is involved. CSVD damages long-range white matter tracts connecting nodes within distributed brain networks. It also disrupts frontosubcortical circuits and cholinergic fiber tracts mediating attentional processes. These changes, illustrated within a model of network dynamics, synergistically relate to neurodegenerative pathology contributing to dementia. The effects of CSVD on attention and executive functioning are best understood within a network model of cognition as revealed by functional neuroimaging. Analysis of network function in CSVD can improve characterizati...
    [This corrects the article on p. 898 in vol. 8, PMID: 25477801.].
    Whereas source memory involves remembering from whom you have heard something, destination memory involves remembering to whom you have told something. Despite its practical relevance, destination memory has been studied little. Recently,... more
    Whereas source memory involves remembering from whom you have heard something, destination memory involves remembering to whom you have told something. Despite its practical relevance, destination memory has been studied little. Recently, two reports suggested that generally destination memory should be poorer than source memory, and that it should be particularly difficult for older people. We tested these predictions by having young and older participants read sentences to two examiners (destination encoding) and listen to sentences read by two examiners (source encoding), under intentional (Experiment 1) or incidental encoding (Experiments 2 and 3). Only in Experiment 3 (in which cognitive demands during destination encoding were increased) was destination memory significantly poorer than source memory. In none of the experiments were older adults inferior to the young on destination or source memory. Destination- and source-memory scores were significantly correlated. Item memory was consistently superior for sentences that had been read out loud (during destination encoding) versus those that had been heard (during source encoding). Destination memory needs not always be poorer than source memory, appears not to be particularly impaired by normal ageing and may depend on similar processes to those supporting source memory.
    Limb apraxia is a neurological deficit characterized by an inability to pantomime and/or imitate gestures, which can result from neurodegenerative disorders such as... more
    Limb apraxia is a neurological deficit characterized by an inability to pantomime and/or imitate gestures, which can result from neurodegenerative disorders such as Alzheimer's disease (AD). The major goal of the study was to describe comprehensively the apraxia deficits observed in AD patients and to relate those deficits to general cognitive status, measures of daily activity, and other neuropsychological measures. Limb apraxia was assessed on a variety of conceptual and gesture production tasks in 30 AD patients. As a group, AD patients were impaired across gesture production tasks: of note was the greater impairment in imitation, as opposed to pantomime, which was especially pronounced when patients were imitating with a delay. Imitation performance was best predicted by measures of visuospatial processing, while imitation with delay was best predicted by measures of working memory. In addition, pantomime in response to pictures of tools was less accurate than Pantomime to Verbal Command and holding the tool during performance did not decrease the participants' impairment, while introducing a verbal cue during imitation increased the severity of deficits. Furthermore, investigation into patterns of deficits clearly demonstrated that the nature of limb apraxia deficits observed in AD can be quite heterogeneous and that dissociations between the conceptual and the production system exist. Finally, we also report on significant correlations between general cognitive status and limb apraxia.
    Recognition memory can be subdivided into two processes: recollection (a contextually rich memory) and familiarity (a sense that an item is old). The brain network supporting recognition encompasses frontal, parietal and medial temporal... more
    Recognition memory can be subdivided into two processes: recollection (a contextually rich memory) and familiarity (a sense that an item is old). The brain network supporting recognition encompasses frontal, parietal and medial temporal regions. Which specific regions within the frontal lobe are critical for recollection vs. familiarity, however, are unknown; past studies of focal lesion patients have yielded conflicting results. We examined patients with focal lesions confined to medial polar (MP), right dorsal frontal (RDF), right frontotemporal (RFT), left dorsal frontal (LDF), temporal, and parietal regions and matched controls. A series of words and their humorous definitions were presented either auditorily or visually to all participants. Recall, recognition, and source memory were tested at 30 min and 24 hr delay, along with “remember/know” judgements for recognized items. The MP, RDF, temporal and parietal groups were impaired on subjectively reported recollection; their intact recognition performance was supported by familiarity. None of the groups were impaired on cued recall, recognition familiarity or source memory. These findings suggest that the MP and RDF regions, along with parietal and temporal regions, are necessary for subjectively-reported recollection, while the LDF and right frontal ventral regions, as those affected in the RTF group, are not.