1,649 research outputs found
Spatial mental models derived from the integration of information from different perspectives
No full textPeople experience environments in many different ways: by moving through it, by inspecting it from above (flying, being in a skyscraper), by listening to a description, by studying a map. One salient point of difference between these experiences is the perspec- tive on the environment, route or survey. Yet re- search to date has not conclusively outlined how people integrate information from different perspec- tives in a unique mental model and how perspective differences during learning impact the resultant cog- nitive maps. Some research suggests that the cognitive maps reflect the perspective differences (e.g., Thorn- dkye and Hayes-Roth 1982); other studies suggest a single, well-integrated representation which affords cognitive flexibility (Taylor and Tversky 1992). One suggestion offered to reconcile these findings focuses on learning goals and subsequent attentional focus differences while experiencing the environment (Taylor et al. 1999) Another potential explanation focuses on individual differences. The present study examines how people integrate spatial information F. Pazzaglia (&) Æ D. Varotto University of Padua, Padua, Italy e-mail: [email protected] H. A. Taylor Tufts University, Medford, MA, USA from route and survey perspectives, when they are provided with information from both perspectives and with specific directions that focus attention either on landmarks or on intersections along a path. Partici- pants’ individual differences in spatial representation are also recorded
A comparison of updating processes in children good or poor in arithmetic word problem-solving
No full textThis study examines the updating ability of poor or good problem solvers. Seventy-eight fourth-graders, 43 good and 35 poor arithmetic word problem-solvers, performed the Updating Test used in Palladino et al. [Palladino, P., Cornoldi, C., De Beni, R., and Pazzaglia F. (2002). Working memory and updating processes in reading comprehension. Memory and Cognition, 29, 344–354.]. The participants listened to wordlists, each comprising 12 words referring to objects or animals of different sizes. At the end of each list participants were asked to recall the 3 or 5 words denoting the smallest objects/animals in the list. Results show that poor problem-solvers recalled fewer correct words and made more intrusion errors (recall of non-target words) than good problem-solvers. Results support the hypothesis that the ability to select and update relevant, and suppress irrelevant information, is related to problem-solving, even when the influence of reading comprehension is controlled for. With reference to Baddeley’s, and other recent WM models [Miyake, A., and Shah, P. (Eds.), (1999). Models of working memory: Mechanisms of active maintenance and executive control. New York: Cambridge University Press.], our results point to the idea that problem-solving relies on the central executive for processing and updating information contained in the problems
Does spatial interference affect spatial text processing in individual with high mental rotation ability?
No full textSome studies have shown that individual differences in spatial abilities play an important role in the comprehension of spatial descriptions (de Vega 1994; Haenggi et al. 1995; Pazzaglia and Cornoldi 1999). The mental rotation test (MRT, Vandenberg and Kuse 1978) is a rigorous measure of spatial ability that correlates with other spatial and visual abilities, and is also a good marker of spatial strategies (Casey 2003). Haenggi et al. (1995) found that mental rotation ability is correlated with the construction of a spatial mental model (Johnson-Laird 1983) derived from a narrative text. In recent years, a number of studies have investigated the cognitive processes, such as temporary memory functions, involved in the processing of spatial mental models. Some, using the Baddeley model of WM (1986), showed the specific involvement of visuo-spatial working memory (VSWM) in the processing of illustrated (Gyselinck et al. 2002) and spatial texts (De Beni et al. 2005; Pazzaglia et al. 2006). In the present study we investigate the relationship between MR ability and WM components in the processing of spatial and non-spatial texts
A mechanistic model for medulloblastoma induction in mice
No full textMedulloblastomas in Patched heterozygous mice (Ptc1+/- mice) are induced with high probability by ionizing radiation applied in the immediate post-natal period. A mathematical model is described here that accommodates the dependence of the medulloblastoma incidence on dose, age at exposure and age. The model assumes that the first step in the development of the cancer is already present in all cells of the patched mouse due to germ-line inactivation of one allele of the patched tumor suppressor gene. The subsequent rate-limiting step is dependent linearly on dose at least up to 3 Gy. The observed strong decrease in carcinogenic effect of radiation between exposure on day 1 and day 10 is described by a physiological elimination of target cells during post-natal maturation of the brain. A single malignant cell develops into a tumor following a gamma-distribution with mean of about 160 days. The multiplicity of medulloblastomas is predicted. © 2013 by Radiation Research Society. All rights of reproduction in any form reserved
Alterations in morphology and adult neurogenesis in the dentate gyrus of patched1 heterozygous mice
No full textMany genes controlling neuronal development also regulate adult neurogenesis. We investigated in vivo the effect of Sonic hedgehog (Shh) signaling activation on patterning and neurogenesis of the hippocampus and behavior of Patched1 (Ptch1) heterozygous mice (Ptch1+/−). We demonstrated for the first time, that Ptch1+/− mice exhibit morphological, cellular and molecular alterations in the dentate gyrus (DG), including elongation and reduced width of the DG as well as deregulations at multiple steps during lineage progression from neural stem cells to neurons. By using stage-specific cellular markers, we detected reduction of quiescent stem cells, newborn neurons and astrocytes and accumulation of proliferating intermediate progenitors, indicative of defects in the dynamic transition among neural stages. Phenotypic alterations in Ptch1+/− mice were accompanied by expression changes in Notch pathway downstream components and TLX nuclear receptor, as well as perturbations in inflammatory and synaptic networks and mouse behavior, pointing to complex biological interactions and highlighting cooperation between Shh and Notch signaling in the regulation of neurogenesis. © 2018 Antonelli, Casciati, Tanori, Tanno, Linares-Vidal, Serra, Bellés, Pannicelli, Saran and Pazzaglia
Perspective, Instruction, and Cognitive Style in Spatial Representation of a Virtual Environment
No full textAn environment can be experienced by moving around in it, inspecting it from above, studying a map, or listening to a verbal description. How does learning from different spatial perspectives together with instructions to focus on particular aspects of an environment, affect one’s cognitive map? Fifty-four undergraduates (30 females, 24 males) learned a route through an urban virtual environment from either a map (survey perspective) or from virtual navigation (route perspective), with instructions to focus either on landmarks or on intersections. The survey group learned the environment by watching a dot moving through a map, whereas the route group learned by watching a virtual person walking through the virtual environment.While learning, participants were stopped at critical points and instructions focused their attention on either land- marks or intersections. After learning, all participants performed several spatial tasks: navigation, map drawing, and pointing. Individual differences in the cognitive style of spatial representation were assessed. Results showed that spatial perspective and individual differences in spatial representations interacted to affect performance
Adding two equivalence relations to the interval temporal logic AB
No full textAbstract. The interval temporal logic AB features two modalities that make it possible to access intervals which are adjacent to the right of the current interval (modality 〈A〉) and proper subintervals that have the same left endpoint of it (modality 〈B〉). AB is one of the most significant interval logics, as it allows one to express meaningful (metric) properties, while maintaining decidability (undecidability rules over interval logics, AB is EXPSPACE-complete [14]). In an attempt to capture ωS-regular languages with interval logics [15], it was proved that AB extended with an equivalence relation, denoted AB∼, is decidable (non-primitive re-cursive) on the class of finite linear orders and undecidable on N. The question whether the addition of two or more equivalence relations makes finite satisfiability for AB undecidable was left open. In this paper, we answer this question proving that AB∼1∼2 is undecidable.
Commentary on: “The body social: an enactive approach to the self“. A tool for merging bodily and social self in immobile individuals
No full textCommentary on: “The body social: an enactive approach to the self“. A tool for merging bodily and social self in immobile individual
A disorder which occurs on standing”: The Earliest Account of Orthostatic Tremor by Pazzaglia
No full textThe earliest account of orthostatic tremor (OT) dates back to 1970, when Pazzaglia and colleagues reported on three patients with a peculiar disorder only occurring on standing. Although Pazzaglia et al. did not use the term OT, they first provided both the clinical and neurophysiological features of such a condition
The assessment of imagery and visuo-spatialworking memory functions in childrenand adults
No full textExperimental evidence has shown the involvement of visuo-spatial working memory (VSWM) in a large number of every-day tasks, such as generation, maintenance and transformation of visual mental images (Kosslyn 1980), processing of visual and spatial coordinates (Hanley, Young & Pearson 1991), map learning and navigation (Denis, Daniel, Fontaine & Pazzaglia 2001; Garden, Cornoldi & Logie 2002), drawing and memory for the positioning of objects (Postma & De Haan 1996; Zimmer, Speiser, & Seidler 2003). In Baddeley’s (1986) original model the system responsible for the storage and processing of non-verbal information was the visuo-spatial sketchpad, or, following the naming used in more recent models (Logie 1995; Cornoldi & Vecchi 2003), visuospatial working memory (VSWM). Although there is converging evidence supporting the multi-componential nature of the VSWM, so far there is no agreement on the number and identity of its components
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