Search results for "Project"
showing 10 items of 3466 documents
Spared place and object-place learning but limited spatial working memory capacity in rats with selective lesions of the dentate gyrus
2007
We studied the cognitive performance of rats with colchicine-induced lesions of the hippocampal dentate gyrus (DG) on a range of spatial, non-spatial and mixed spatial/procedural tasks. Rats were assigned to three experimental groups receiving large colchicine lesions (7 μg per hippocampus), small colchicine lesions (1.75 μg per hippocampus) or sham lesions. Stereological estimates of cell density indicated that the colchicine treatments induced dose-dependent damage to the DG, while sparing in large part other hippocampal subfields. Remarkably, the behavioural results showed that the colchicine lesions did not affect the performance of rats in an object discrimination task, in an object-pl…
Becoming a beer expert: is simple exposure with feedback sufficient to learn beer categories?
2015
Category learning is an important aspect of expertise development which had been little studied in the chemosensory field. The wine literature suggests that through repeated exposure to wines, sensory information is stored by experts as prototypes. The goal of this study was to further explore this issue using beers. We tested the ability of beer consumers to correctly categorize beers from two different categories (top- and bottom-fermented beers) before and after repeated exposure with feedback to beers from these categories. We found that participants learned to identify the category membership of beers to which they have been exposed but were unable to generalize their learning to other…
Environmental barriers, person-environment fit and mortality among community-dwelling very old people
2013
Background. Environmental barriers are associated with disability-related outcomes in older people but little is known of the effect of environmental barriers on mortality. The aim of this study was to examine whether objectively measured barriers in the outdoor, entrance and indoor environments are associated with mortality among community-dwelling 80- to 89-year-old single-living people. Methods. This longitudinal study is based on a sample of 397 people who were single-living in ordinary housing in Sweden. Participants were interviewed during 2002–2003, and 393 were followed up for mortality until May 15, 2012. Environmental barriers and functional limitations were assessed with the Hous…
Learning to learn: Theta oscillations predict new learning, which enhances related learning and neurogenesis
2011
Animals in the natural world continuously encounter learning experiences of varying degrees of novelty. New neurons in the hippocampus are especially responsive to learning associations between novel events and more cells survive if a novel and challenging task is learned. One might wonder whether new neurons would be rescued from death upon each new learning experience or whether there is an internal control system that limits the number of cells that are retained as a function of learning. In this experiment, it was hypothesized that learning a task that was similar in content to one already learned previously would not increase cell survival. We further hypothesized that in situations in…
Absolute Memory for Tempo in Musicians and Non-Musicians
2016
The ability to remember tempo (the perceived frequency of musical pulse) without external references may be defined, by analogy with the notion of absolute pitch, as absolute tempo (AT). Anecdotal reports and sparse empirical evidence suggest that at least some individuals possess AT. However, to our knowledge, no systematic assessments of AT have been performed using laboratory tasks comparable to those assessing absolute pitch. In the present study, we operationalize AT as the ability to identify and reproduce tempo in the absence of rhythmic or melodic frames of reference and assess these abilities in musically trained and untrained participants. We asked 15 musicians and 15 non-musician…
Conceptual implicit memory: a developmental study.
1995
The widely accepted standpoint that implicit memory emerges earlier in development than explicit memory, and is more stable from childhood to adult age, is based on experimental data essentially collected in perceptual tasks. The present study was aimed at investigating whether these findings still hold when a more conceptual task is used. We compared the performance of children at two age levels (2nd and 4th grades) on a category-exemplar generation task. Results showed that performances of the two groups were comparable when the target items were typical of their categories, as in Experiment 2, and for a subset of the items in Experiment 1. However, the older children outperformed the you…
Topical allopurinol or corticosteroids and acetylcysteine in the early treatment of experimental corneal alkali burns: a pilot study.
2002
PURPOSE. To investigate the effect of topical allopurinol on experimental corneal burns and to compare this to established treatment modalities such as topical prednisolone and acetylcysteine. METHODS. Twenty Wistar rats were randomly assigned to four groups (n=5 each). The groups were controls (normal saline), allopurinol 0.4% eye drops, prednisolone acetate 1% eye drops and acetylcysteine 8% eyedrops. Corneal burn was induced using a 3 mm paper disc soaked in 1N NaOH for 60 seconds. Drops were instilled 6 times per day. In addition, one drop/day ofloxacine was given to prevent secondary infections. Eyes were enucleated 50 hours later and fixed in 4.5% formaldehyde. Three histological leve…
Activity of Thigh Muscles During Static and Dynamic Stances in Stroke Patients: A Pilot Case-Control Study
2014
Impaired postural control is a key characteristic of mobility problems in stroke patients and has great impact on the incidence of falls and on the level of independence in activities of daily living. The role played by the thigh muscles in balance impairment in stroke patients has not been sufficiently investigated. This study investigated the activities of the thigh muscles in stroke patients during standing balance manipulations.Ten stroke patients and 15 healthy subjects performed 5 upright standing tasks on a force platform: normal standing with eyes open, normal standing with eyes closed, feet together, semi-tandem standing, and a dynamic measurement along a predefined route. The post…
Effects of dual task difficulty in motor and cognitive performance: Differences between adults and adolescents
2017
In the present study our aim was to compare dual-task performance in thirteen adolescents and fifteen young adults while concurrently performing a cognitive and a motor task. The postural control variables were obtained under three different conditions: i) bipedal stance, ii) tandem stance and iii) unipedal stance. The cognitive task consisted of a backward digit span test in which the participants were asked to memorize a sequence of numbers and then repeat the number in reverse order at three different difficulty levels (i.e. with 3, 4 and 5 digits). The difficulty of the cognitive task was seen to have different effects on adolescents and young adults. Adolescents seem to prioritize post…
Effects of A Dual-Task Intervention in Postural Control and Cognitive Performance in Adolescents.
2019
The aim was to assess dual- versus single-task training for motor performance and cognitive performance in adolescents. Two experiments were performed. In the first, 30 adolescents were randomized to three groups to determine the effect of dual-task difficulty on postural control: α-scaling and root mean square (RMS). In the second, 20 adolescents were randomized to two groups to determine the effect of dual-task practice to improve working memory. RMS in the post-test was lower than the pre-test in both dual-task groups, while α-scaling was lower in post-test than pre-test only in the high-difficulty dual-task group. A practice effect was observed on the percentage of correct answers only …